Discrete symmetry breaking and baryon currents in U(N) and SU(N) gauge theories

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lucini, B.; Patella, A.

2009-06-15

In SU(N) gauge theories with fermions in the fundamental or in a two-index (either symmetric or antisymmetric) representation formulated on a manifold with at least one compact dimension with nontrivial holonomy the discrete symmetries C, P, and T are broken at small enough size of the compact direction(s) for certain values of N. We show that for those N in the broken phase a nonzero baryon current wrapping in the compact direction exists, which provides a measurable observable for the breaking of C, P, and T. We prove that in all cases where the current is absent there is nomore » breaking of those discrete symmetries. This includes the limit N{yields}{infinity} of the SU(N) gauge theory with symmetric or antisymmetric fermions and U(N) gauge theory at any value of N. We then argue that the component of the baryon current in the compact direction is the physical order parameter for C, P, and T breaking due to the breaking of Lorentz invariance.« less

Flavored gauge mediation with discrete non-Abelian symmetries

NASA Astrophysics Data System (ADS)

Everett, Lisa L.; Garon, Todd S.

2018-05-01

We explore the model building and phenomenology of flavored gauge-mediation models of supersymmetry breaking in which the electroweak Higgs doublets and the S U (2 ) messenger doublets are connected by a discrete non-Abelian symmetry. The embedding of the Higgs and messenger fields into representations of this non-Abelian Higgs-messenger symmetry results in specific relations between the Standard Model Yukawa couplings and the messenger-matter Yukawa interactions. Taking the concrete example of an S3 Higgs-messenger symmetry, we demonstrate that, while the minimal implementation of this scenario suffers from a severe μ /Bμ problem that is well known from ordinary gauge mediation, expanding the Higgs-messenger field content allows for the possibility that μ and Bμ can be separately tuned, allowing for the possibility of phenomenologically viable models of the soft supersymmetry-breaking terms. We construct toy examples of this type that are consistent with the observed 125 GeV Higgs boson mass.

Neutrino masses, dark matter and leptogenesis with U(1) B - L gauge symmetry

NASA Astrophysics Data System (ADS)

Geng, Chao-Qiang; Okada, Hiroshi

2018-06-01

We propose a model with an U(1) B - L gauge symmetry, in which small neutrino masses, dark matter and the matter-antimatter asymmetry in the Universe can be simultaneously explained. In particular, the neutrino masses are generated radiatively, while the matter-antimatter asymmetry is led by the leptogenesis mechanism, at TeV scale. We also explore allowed regions of the model parameters and discuss some phenomenological effects, including lepton flavor violating processes.

Dirac dark matter and b →s ℓ+ℓ- with U(1) gauge symmetry

NASA Astrophysics Data System (ADS)

Celis, Alejandro; Feng, Wan-Zhe; Vollmann, Martin

2017-02-01

We revisit the possibility of a Dirac fermion dark matter candidate in the light of current b →s ℓ+ℓ- anomalies by investigating a minimal extension of the Standard Model with a horizontal U(1 ) ' local symmetry. Dark matter stability is protected by a remnant Z2 symmetry arising after spontaneous symmetry breaking of U(1 ) '. The associated Z' gauge boson can accommodate current hints of new physics in b →s ℓ+ℓ- decays, and acts as a vector portal between dark matter and the visible sector. We find that the model is severely constrained by a combination of precision measurements at flavor factories, LHC searches for dilepton resonances, as well as direct and indirect dark matter searches. Despite this, viable regions of the parameter space accommodating the observed dark matter relic abundance and the b →s ℓ+ℓ-anomalies still persist for dark matter and Z ' masses in the TeV range.

Towards gauge coupling unification in left-right symmetric SU (3 )c×SU (3 )L×SU (3 )R×U (1 )X theories

NASA Astrophysics Data System (ADS)

Hati, Chandan; Patra, Sudhanwa; Reig, Mario; Valle, José W. F.; Vaquera-Araujo, C. A.

2017-07-01

We consider the possibility of gauge coupling unification within the simplest realizations of the SU (3 )c×SU (3 )L×SU (3 )R×U (1 )X gauge theory. We present a first exploration of the renormalization group equations governing the "bottom-up" evolution of the gauge couplings in a generic model with free normalization for the generators. Interestingly, we find that for a SU (3 )c×SU (3 )L×SU (3 )R×U (1 )X symmetry breaking scale MX as low as a few TeV one can achieve unification in the presence of leptonic octets. We briefly comment on possible grand unified theory frameworks which can embed the SU (3 )c×SU (3 )L×SU (3 )R×U (1 )X model as well as possible implications, such as lepton flavor violating physics at the LHC.

ɛ '/ ɛ anomaly and neutron EDM in SU(2) L × SU(2) R × U(1) B- L model with charge symmetry

NASA Astrophysics Data System (ADS)

Haba, Naoyuki; Umeeda, Hiroyuki; Yamada, Toshifumi

2018-05-01

The Standard Model prediction for ɛ '/ ɛ based on recent lattice QCD results exhibits a tension with the experimental data. We solve this tension through W R + gauge boson exchange in the SU(2) L × SU(2) R × U(1) B- L model with `charge symmetry', whose theoretical motivation is to attribute the chiral structure of the Standard Model to the spontaneous breaking of SU(2) R × U(1) B- L gauge group and charge symmetry. We show that {M_W}{_R}<58 TeV is required to account for the ɛ' /ɛ anomaly in this model. Next, we make a prediction for the neutron EDM in the same model and study a correlation between ɛ ' /ɛ and the neutron EDM. We confirm that the model can solve the ɛ ' /ɛ anomaly without conflicting the current bound on the neutron EDM, and further reveal that almost all parameter regions in which the ɛ ' /ɛ anomaly is explained will be covered by future neutron EDM searches, which leads us to anticipate the discovery of the neutron EDM.

Comment on 'Noncommutative gauge theories and Lorentz symmetry'

DOE Office of Scientific and Technical Information (OSTI.GOV)

Iorio, Alfredo

2008-02-15

We show that Lorentz symmetry is generally absent for noncommutative (Abelian) gauge theories and obtain a compact formula for the divergence of the Noether currents that allows a thorough study of this instance of symmetry violation. We use that formula to explain why the results of ''Noncommutative gauge theories and Lorentz symmetry'', Phys. Rev. D 70, 125004 (2004) by R. Banerjee, B. Chakraborty, and K. Kumar, interpreted there as new criteria for Lorentz invariance, are in fact just a particular case of the general expression for Lorentz violation obtained here. Finally, it is suggested that the divergence formula should holdmore » in a vast class of cases, such as, for instance, the standard model extension.« less

Neutrinophilic two Higgs doublet model with dark matter under an alternative U(1)_{B-L} gauge symmetry

NASA Astrophysics Data System (ADS)

Nomura, Takaaki; Okada, Hiroshi

2018-03-01

We propose a Dirac type active neutrino with rank two mass matrix and a Majorana fermion dark matter candidate with an alternative local U(1)_{B-L} extension of neutrinophilic two Higgs doublet model. Our dark matter candidate can be stabilized due to charge assignment under the gauge symmetry without imposing extra discrete Z_2 symmetry and the relic density is obtained from an Z' boson exchanging process. Taking into account collider constraints on the Z' boson mass and coupling, we estimate the relic density.

Local U(2,2) symmetry in relativistic quantum mechanics

NASA Astrophysics Data System (ADS)

Finster, Felix

1998-12-01

Local gauge freedom in relativistic quantum mechanics is derived from a measurement principle for space and time. For the Dirac equation, one obtains local U(2,2) gauge transformations acting on the spinor index of the wave functions. This local U(2,2) symmetry allows a unified description of electrodynamics and general relativity as a classical gauge theory.

Loop induced type-II seesaw model and GeV dark matter with U(1)B - L gauge symmetry

NASA Astrophysics Data System (ADS)

Nomura, Takaaki; Okada, Hiroshi

2017-11-01

We propose a model with U(1) B - L gauge symmetry and several new fermions in no conflict with anomaly cancellation where the neutrino masses are given by the vacuum expectation value of Higgs triplet induced at the one-loop level. The new fermions are odd under discrete Z2 symmetry and the lightest one becomes dark matter candidate. We find that the mass of dark matter is typically O (1)- O (10) GeV. Then relic density of the dark matter is discussed.

Higgs mechanism in higher-rank symmetric U(1) gauge theories

NASA Astrophysics Data System (ADS)

Bulmash, Daniel; Barkeshli, Maissam

2018-06-01

We use the Higgs mechanism to investigate connections between higher-rank symmetric U(1 ) gauge theories and gapped fracton phases. We define two classes of rank-2 symmetric U(1 ) gauge theories: the (m ,n ) scalar and vector charge theories, for integer m and n , which respect the symmetry of the square (cubic) lattice in two (three) spatial dimensions. We further provide local lattice rotor models whose low-energy dynamics are described by these theories. We then describe in detail the Higgs phases obtained when the U(1 ) gauge symmetry is spontaneously broken to a discrete subgroup. A subset of the scalar charge theories indeed have X-cube fracton order as their Higgs phase, although we find that this can only occur if the continuum higher-rank gauge theory breaks continuous spatial rotational symmetry. However, not all higher-rank gauge theories have fractonic Higgs phases; other Higgs phases possess conventional topological order. Nevertheless, they yield interesting novel exactly solvable models of conventional topological order, somewhat reminiscent of the color code models in both two and three spatial dimensions. We also investigate phase transitions in these models and find a possible direct phase transition between four copies of Z2 gauge theory in three spatial dimensions and X-cube fracton order.

Gauging hidden symmetries in two dimensions

NASA Astrophysics Data System (ADS)

Samtleben, Henning; Weidner, Martin

2007-08-01

We initiate the systematic construction of gauged matter-coupled supergravity theories in two dimensions. Subgroups of the affine global symmetry group of toroidally compactified supergravity can be gauged by coupling vector fields with minimal couplings and a particular topological term. The gauge groups typically include hidden symmetries that are not among the target-space isometries of the ungauged theory. The gaugings constructed in this paper are described group-theoretically in terms of a constant embedding tensor subject to a number of constraints which parametrizes the different theories and entirely encodes the gauged Lagrangian. The prime example is the bosonic sector of the maximally supersymmetric theory whose ungauged version admits an affine fraktur e9 global symmetry algebra. The various parameters (related to higher-dimensional p-form fluxes, geometric and non-geometric fluxes, etc.) which characterize the possible gaugings, combine into an embedding tensor transforming in the basic representation of fraktur e9. This yields an infinite-dimensional class of maximally supersymmetric theories in two dimensions. We work out and discuss several examples of higher-dimensional origin which can be systematically analyzed using the different gradings of fraktur e9.

Galactic center γ-ray excess in hidden sector DM models with dark gauge symmetries: local Z{sub 3} symmetry as an example

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ko, P.; Tang, Yong

We show that hidden sector dark matter (DM) models with local dark gauge symmetries make a natural playground for the possible γ-ray excess from the galactic center (GC). We first discuss in detail the GC γ-ray excess in a scalar dark matter (DM) model with local Z{sub 3} symmetry which was recently proposed by the present authors. Within this model, scalar DM with mass 30–70 GeV is allowed due to the newly-opened (semi-)annihilation channels of a DM pair into dark Higgs ϕ and/or dark photon Z′ pair, and the γ-ray spectrum from the GC can be fit within this model.more » Then we argue that the GC gamma ray excess can be easily accommodated within hidden sector dark matter models where DM is stabilized by local gauge symmetries, due to the presence of dark Higgs (and also dark photon for Abelian dark gauge symmetry)« less

On gauge independence for gauge models with soft breaking of BRST symmetry

NASA Astrophysics Data System (ADS)

Reshetnyak, Alexander

2014-12-01

A consistent quantum treatment of general gauge theories with an arbitrary gauge-fixing in the presence of soft breaking of the BRST symmetry in the field-antifield formalism is developed. It is based on a gauged (involving a field-dependent parameter) version of finite BRST transformations. The prescription allows one to restore the gauge-independence of the effective action at its extremals and therefore also that of the conventional S-matrix for a theory with BRST-breaking terms being additively introduced into a BRST-invariant action in order to achieve a consistency of the functional integral. We demonstrate the applicability of this prescription within the approach of functional renormalization group to the Yang-Mills and gravity theories. The Gribov-Zwanziger action and the refined Gribov-Zwanziger action for a many-parameter family of gauges, including the Coulomb, axial and covariant gauges, are derived perturbatively on the basis of finite gauged BRST transformations starting from Landau gauge. It is proved that gauge theories with soft breaking of BRST symmetry can be made consistent if the transformed BRST-breaking terms satisfy the same soft BRST symmetry breaking condition in the resulting gauge as the untransformed ones in the initial gauge, and also without this requirement.

Entanglement renormalization and gauge symmetry

NASA Astrophysics Data System (ADS)

Tagliacozzo, L.; Vidal, G.

2011-03-01

A lattice gauge theory is described by a redundantly large vector space that is subject to local constraints and can be regarded as the low-energy limit of an extended lattice model with a local symmetry. We propose a numerical coarse-graining scheme to produce low-energy, effective descriptions of lattice models with a local symmetry such that the local symmetry is exactly preserved during coarse-graining. Our approach results in a variational ansatz for the ground state(s) and low-energy excitations of such models and, by extension, of lattice gauge theories. This ansatz incorporates the local symmetry in its structure and exploits it to obtain a significant reduction of computational costs. We test the approach in the context of a Z2 lattice gauge theory formulated as the low-energy theory of a specific regime of the toric code with a magnetic field, for lattices with up to 16×16 sites (162×2=512 spins) on a torus. We reproduce the well-known ground-state phase diagram of the model, consisting of a deconfined and spin-polarized phases separated by a continuous quantum phase transition, and obtain accurate estimates of energy gaps, ground-state fidelities, Wilson loops, and several other quantities.

Gauged twistor spinors and symmetry operators

NASA Astrophysics Data System (ADS)

Ertem, Ümit

2017-03-01

We consider gauged twistor spinors which are supersymmetry generators of supersymmetric and superconformal field theories in curved backgrounds. We show that the spinor bilinears of gauged twistor spinors satisfy the gauged conformal Killing-Yano equation. We prove that the symmetry operators of the gauged twistor spinor equation can be constructed from ordinary conformal Killing-Yano forms in constant curvature backgrounds. This provides a way to obtain gauged twistor spinors from ordinary twistor spinors.

Accidental Peccei-Quinn Symmetry Protected to Arbitrary Order

NASA Astrophysics Data System (ADS)

Di Luzio, Luca; Nardi, Enrico; Ubaldi, Lorenzo

2017-07-01

A S U (N )L×S U (N )R gauge theory for a scalar multiplet Y transforming in the bifundamental representation (N ,N ¯) preserves, for N >4 , an accidental U (1 ) symmetry first broken at operator dimension N . A vacuum expectation value for Y can break the symmetry to Hs=S U (N )L+R or to Hh=S U (N -1 )L×S U (N -1 )R×U (1 )L +R . In the first case the accidental U (1 ) gets also broken, yielding a pseudo-Nambu-Goldstone boson with mass suppression controlled by N . In the second case a global U (1 ) remains unbroken. The strong C P problem is solved by coupling Y to new fermions carrying color. The first case allows for a Peccei-Quinn solution with U (1 )PQ protected by the gauge symmetry up to order N . In the second case U (1 ) can get broken by condensates of the new strong dynamics, resulting in a composite axion. By coupling Y to fermions carrying only weak isospin, models for axionlike particles can be constructed.

Baryonic Force for Accelerated Cosmic Expansion and Generalized U1b Gauge Symmetry in Particle-Cosmology

NASA Astrophysics Data System (ADS)

Khan, Mehbub; Hao, Yun; Hsu, Jong-Ping

2018-01-01

Based on baryon charge conservation and a generalized Yang-Mills symmetry for Abelian (and non-Abelian) groups, we discuss a new baryonic gauge field and its linear potential for two point-like baryon charges. The force between two point-like baryons is repulsive, extremely weak and independent of distance. However, for two extended baryonic systems, we have a dominant linear force α r. Thus, only in the later stage of the cosmic evolution, when two baryonic galaxies are separated by an extremely large distance, the new repulsive baryonic force can overcome the gravitational attractive force. Such a model provides a gauge-field-theoretic understanding of the late-time accelerated cosmic expansion. The baryonic force can be tested by measuring the accelerated Wu-Doppler frequency shifts of supernovae at different distances.

Hidden gauged U (1 ) model: Unifying scotogenic neutrino and flavor dark matter

NASA Astrophysics Data System (ADS)

Yu, Jiang-Hao

2016-06-01

In both scotogenic neutrino and flavor dark matter models, the dark sector communicates with the standard model fermions via Yukawa portal couplings. We propose an economic scenario where the scotogenic neutrino and a flavored mediator share the same inert Higgs doublet and all are charged under a hidden gauged U (1 ) symmetry. The dark Z2 symmetry in the dark sector is regarded as the remnant of this hidden U (1 ) symmetry breaking. In particular, we investigate a dark U (1 )D [and also U (1 )B-L] model which unifies the scotogenic neutrino and top-flavored mediator. Thus dark tops and dark neutrinos are the standard model fermion partners, and the dark matter could be the inert Higgs or the lightest dark neutrino. We note that this model has rich collider signatures on dark tops, the inert Higgs and the Z' gauge boson. Moreover, the scalar associated to the U (1 )D [and also U (1 )B -L ] symmetry breaking could explain the 750 GeV diphoton excess reported by ATLAS and CMS recently.

Unity of quark and lepton interactions with symplectic gauge symmetry

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rajpoot, S.

1982-07-01

Properties of symplectic groups are reviewed and the gauge structure of Sp(2n) derived. The electroweak unification of leptons within Sp(8) gauge symmetry and grand unification of quarks and leptons within Sp(10) gauge symmetry are discussed.

On the dualization of scalars into ( d - 2)-forms in supergravity. Momentum maps, R-symmetry and gauged supergravity

NASA Astrophysics Data System (ADS)

Bandos, Igor A.; Ortín, Tomás

2016-08-01

We review and investigate different aspects of scalar fields in supergravity theories both when they parametrize symmetric spaces and when they parametrize spaces of special holonomy which are not necessarily symmetric (Kähler and Quaternionic-Kähler spaces): their rôle in the definition of derivatives of the fermions covariant under the R-symmetry group and (in gauged supergravities) under some gauge group, their dualization into ( d - 2)-forms, their role in the supersymmetry transformation rules (via fermion shifts, for instance) etc. We find a general definition of momentum map that applies to any manifold admitting a Killing vector and coincides with those of the holomorphic and tri-holomorphic momentum maps in Kähler and quaternionic-Kähler spaces and with an independent definition that can be given in symmetric spaces. We show how the momen-tum map occurs ubiquitously: in gauge-covariant derivatives of fermions, in fermion shifts, in the supersymmetry transformation rules of ( d - 2)-forms etc. We also give the general structure of the Noether-Gaillard-Zumino conserved currents in theories with fields of different ranks in any dimension.

A radiative neutrino mass model in light of DAMPE excess with hidden gauged U(1) symmetry

NASA Astrophysics Data System (ADS)

Nomura, Takaaki; Okada, Hiroshi; Wu, Peiwen

2018-05-01

We propose a one-loop induced neutrino mass model with hidden U(1) gauge symmetry, in which we successfully involve a bosonic dark matter (DM) candidate propagating inside a loop diagram in neutrino mass generation to explain the e+e‑ excess recently reported by the DArk Matter Particle Explorer (DAMPE) experiment. In our scenario dark matter annihilates into four leptons through Z' boson as DM DM → Z' Z' (Z' → l+ l‑) and Z' decays into leptons via one-loop effect. We then investigate branching ratios of Z' taking into account lepton flavor violations and neutrino oscillation data.

Model with a gauged lepton flavor SU(2) symmetry

NASA Astrophysics Data System (ADS)

Chiang, Cheng-Wei; Tsumura, Koji

2018-05-01

We propose a model having a gauged SU(2) symmetry associated with the second and third generations of leptons, dubbed SU(2) μτ , of which U{(1)}_{L_{μ }-L_{τ }} is an Abelian subgroup. In addition to the Standard Model fields, we introduce two types of scalar fields. One exotic scalar field is an SU(2) μτ doublet and SM singlet that develops a nonzero vacuum expectation value at presumably multi-TeV scale to completely break the SU(2) μτ symmetry, rendering three massive gauge bosons. At the same time, the other exotic scalar field, carrying electroweak as well as SU(2) μτ charges, is induced to have a nonzero vacuum expectation value as well and breaks mass degeneracy between the muon and tau. We examine how the new particles in the model contribute to the muon anomalous magnetic moment in the parameter space compliant with the Michel decays of tau.

Gauge Theories and Spontaneous Symmetry Breaking.

DTIC Science & Technology

1980-11-01

This report summarizes attempts to understand in what way spontaneous symmetry breaking arose in the context of guage field theories of elementary...gauge field theories. It was felt that the symmetry breaking used by the physicists (a procedure known as the Higgs mechanism) is not precisely a

Field-theory representation of gauge-gravity symmetry-protected topological invariants, group cohomology, and beyond.

PubMed

Wang, Juven C; Gu, Zheng-Cheng; Wen, Xiao-Gang

2015-01-23

The challenge of identifying symmetry-protected topological states (SPTs) is due to their lack of symmetry-breaking order parameters and intrinsic topological orders. For this reason, it is impossible to formulate SPTs under Ginzburg-Landau theory or probe SPTs via fractionalized bulk excitations and topology-dependent ground state degeneracy. However, the partition functions from path integrals with various symmetry twists are universal SPT invariants, fully characterizing SPTs. In this work, we use gauge fields to represent those symmetry twists in closed spacetimes of any dimensionality and arbitrary topology. This allows us to express the SPT invariants in terms of continuum field theory. We show that SPT invariants of pure gauge actions describe the SPTs predicted by group cohomology, while the mixed gauge-gravity actions describe the beyond-group-cohomology SPTs. We find new examples of mixed gauge-gravity actions for U(1) SPTs in (4+1)D via the gravitational Chern-Simons term. Field theory representations of SPT invariants not only serve as tools for classifying SPTs, but also guide us in designing physical probes for them. In addition, our field theory representations are independently powerful for studying group cohomology within the mathematical context.

Rescriptive and Descriptive Gauge Symmetry in Finite-Dimensional Dynamical Systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gurfil, Pini

2007-02-07

Gauge theories in physics constitute a fundamental tool for modeling interactions among electromagnetic, weak and strong forces. They have been used in a myriad of fields, ranging from sub-atomic physics to cosmology. The basic mathematical tool generating the gauge theories is that of symmetry, i.e. a redundancy in the description of the system. Although symmetries have long been recognized as a fundamental tool for solving ordinary differential equations, they have not been formally categorized as gauge theories. In this paper, we show how simple systems described by ordinary differential equations are prone to exhibit gauge symmetry, and discuss a fewmore » practical applications of this approach. In particular, we utilize the notion of gauge symmetry to question some common engineering misconceptions of chaotic and stochastic phenomena, and show that seemingly 'disordered' (deterministic) or 'random' (stochastic) behaviors can be 'ordered'. This brings into play the notion of observation; we show that temporal observations may be misleading when used for chaos detection. From a practical standpoint, we use gauge symmetry to considerably mitigate the numerical truncation error of numerical integrations.« less

Gauged Supergravities and Spontaneous Supersymmetry Breaking from the Double Copy Construction

NASA Astrophysics Data System (ADS)

Chiodaroli, M.; Günaydin, M.; Johansson, H.; Roiban, R.

2018-04-01

Supergravities with gauged R symmetry and Minkowski vacua allow for spontaneous supersymmetry breaking and, as such, provide a framework for building supergravity models of phenomenological relevance. In this Letter, we initiate the study of double copy constructions for these supergravities. We argue that, on general grounds, we expect their scattering amplitudes to be described by a double copy of the type (spontaneously broken gauge theory)⊗ (gauge theory with broken supersymmetry). We present a simple realization in which the resulting supergravity has U (1 )R gauge symmetry, spontaneously broken N =2 supersymmetry, and massive gravitini. This is the first instance of a double copy construction of a gauged supergravity and of a theory with spontaneously broken supersymmetry. The construction extends in a straightforward manner to a large family of gauged Yang-Mills-Einstein supergravity theories with or without spontaneous gauge-symmetry breaking.

Embedded Gaussian unitary ensembles with U(Ω)⊗SU(r) embedding generated by random two-body interactions with SU(r) symmetry

NASA Astrophysics Data System (ADS)

Vyas, Manan; Kota, V. K. B.

2012-12-01

Following the earlier studies on embedded unitary ensembles generated by random two-body interactions [EGUE(2)] with spin SU(2) and spin-isospin SU(4) symmetries, developed is a general formulation, for deriving lower order moments of the one- and two-point correlation functions in eigenvalues, that is valid for any EGUE(2) and BEGUE(2) ("B" stands for bosons) with U(Ω)⊗SU(r) embedding and with two-body interactions preserving SU(r) symmetry. Using this formulation with r = 1, we recover the results derived by Asaga et al. [Ann. Phys. (N.Y.) 297, 344 (2002)], 10.1006/aphy.2002.6248 for spinless boson systems. Going further, new results are obtained for r = 2 (this corresponds to two species boson systems) and r = 3 (this corresponds to spin 1 boson systems).

The massive fermion phase for the U(N) Chern-Simons gauge theory in D=3 at large N

DOE PAGES

Bardeen, William A.

2014-10-07

We explore the phase structure of fermions in the U(N) Chern-Simons Gauge theory in three dimensions using the large N limit where N is the number of colors and the fermions are taken to be in the fundamental representation of the U(N) gauge group. In the large N limit, the theory retains its classical conformal behavior and considerable attention has been paid to possible AdS/CFT dualities of the theory in the conformal phase. In this paper we present a solution for the massive phase of the fermion theory that is exact to the leading order of ‘t Hooft’s large Nmore » expansion. We present evidence for the spontaneous breaking of the exact scale symmetry and analyze the properties of the dilaton that appears as the Goldstone boson of scale symmetry breaking.« less

The anomalous U(1)_{anom} symmetry and flavors from an SU(5) × SU(5)' GUT in Z_{12-I} orbifold compactification

NASA Astrophysics Data System (ADS)

Kim, Jihn E.; Kyae, Bumseok; Nam, Soonkeon

2017-12-01

In string compactifications, frequently the anomalous U(1) gauge symmetry appears which belongs to E_8 × E_8' of the heterotic string. This anomalous U(1) gauge boson obtains mass at the compactification scale (≈ 10^{18 } {GeV}) by absorbing one pseudoscalar (corresponding to the model-independent axion) from the second rank antisymmetric tensor field B_{MN}. Below the compactification scale a global symmetry U(1)_{anom} results whose charge Q_anom is the original gauge U(1) charge. This is the most natural global symmetry, realizing the "invisible" axion. This global symmetry U(1)_{anom} is suitable for a flavor symmetry. In the simplest compactification model with the flipped SU(5) grand unification, all the low energy parameters are calculated in terms of the vacuum expectation values of the standard model singlets.

New U(1) gauge model of radiative lepton masses with sterile neutrino and dark matter

DOE PAGES

Adhikari, Rathin; Borah, Debasish; Ma, Ernest

2016-02-23

Here, an anomaly-free U(1) gauge extension of the standard model (SM) is presented. Only one Higgs doublet with a nonzero vacuum expectation is required as in the SM. New fermions and scalars as well as all SM particles transform nontrivially under this U(1), resulting in a model of three active neutrinos and one sterile neutrino, all acquiring radiative masses. Charged-lepton masses are also radiative as well as the mixing between active and sterile neutrinos. At the same time, a residual Z 2 symmetry of the U(1) gauge symmetry remains exact, allowing for the existence of dark matter.

Boundaries, mirror symmetry, and symplectic duality in 3d N = 4 gauge theory

DOE PAGES

Bullimore, Mathew; Dimofte, Tudor; Gaiotto, Davide; ...

2016-10-20

We introduce several families of N = (2, 2) UV boundary conditions in 3d N=4 gauge theories and study their IR images in sigma-models to the Higgs and Coulomb branches. In the presence of Omega deformations, a UV boundary condition defines a pair of modules for quantized algebras of chiral Higgs- and Coulomb-branch operators, respectively, whose structure we derive. In the case of abelian theories, we use the formalism of hyperplane arrangements to make our constructions very explicit, and construct a half-BPS interface that implements the action of 3d mirror symmetry on gauge theories and boundary conditions. Finally, by studyingmore » two-dimensional compactifications of 3d N = 4 gauge theories and their boundary conditions, we propose a physical origin for symplectic duality $-$ an equivalence of categories of modules associated to families of Higgs and Coulomb branches that has recently appeared in the mathematics literature, and generalizes classic results on Koszul duality in geometric representation theory. We make several predictions about the structure of symplectic duality, and identify Koszul duality as a special case of wall crossing.« less

Electroweak theory based on S U (4 )L⊗U (1 )X gauge group

NASA Astrophysics Data System (ADS)

Long, H. N.; Hue, L. T.; Loi, D. V.

2016-07-01

This paper includes two main parts. In the first part, we present generalized gauge models based on the S U (3 )C⊗S U (4 )L⊗U (1 )X (3-4-1) gauge group with arbitrary electric charges of exotic leptons. The mixing matrix of neutral gauge bosons is analyzed, and the eigenmasses and eigenstates are obtained. The anomaly-free as well as matching conditions are discussed precisely. In the second part, we present a new development of the original 3-4-1 model [R. Foot, H. N. Long, and T. A. Tran, Phys. Rev. D 50, R34 (1994), F. Pisano and V. Pleitez, Phys. Rev. D 51, 3865 (1995).]. Different from previous works, in this paper the neutrinos, with the help of the scalar decuplet H , get the Dirac masses at the tree level. The vacuum expectation value (VEV) of the Higgs boson field in the decuplet H acquiring the VEV responsible for neutrino Dirac mass leads to mixing in separated pairs of singly charged gauge bosons, namely the Standard Model (SM) W boson and K , the new gauge boson acting in the right-handed lepton sector, as well as the singly charged bileptons X and Y . Due to the mixing, there occurs a right-handed current carried by the W boson. From the expression of the electromagnetic coupling constant, ones get the limit of the sine-squared of the Weinberg angle, sin2θW<0.25 , and a constraint on electric charges of extra leptons. In the limit of lepton number conservation, the Higgs sector contains all massless Goldstone bosons for massive gauge bosons and the SM-like Higgs boson. Some phenomenology is discussed.

Spontaneously broken topological SL(5,R) gauge theory with standard gravity emerging

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mielke, Eckehard W.

2011-02-15

A completely metric-free sl(5,R) gauge framework is developed in four dimensions. After spontaneous symmetry breaking of the corresponding topological BF scheme, Einstein spaces with a tiny cosmological constant emerge, similarly as in (anti-)de Sitter gauge theories of gravity. The induced {Lambda} is related to the scale of the symmetry breaking. A ''background'' metric surfaces from a Higgs-like mechanism. The finiteness of such a topological scheme converts into asymptotic safeness after quantization of the spontaneously broken model.

Analysis of the right-handed Majorana neutrino mass in an S U (4 )×S U (2 )L×S U (2 )R Pati-Salam model with democratic texture

NASA Astrophysics Data System (ADS)

Yang, Masaki J. S.

2017-03-01

In this paper, we attempt to build a unified model with the democratic texture, that has some unification between up-type Yukawa interactions Yν and Yu . Since the S3 L×S3 R flavor symmetry is chiral, the unified gauge group is assumed to be Pati-Salam type S U (4 )c×S U (2 )L×S U (2 )R. The breaking scheme of the flavor symmetry is considered to be S3 L×S3 R→S2 L×S2 R→0 . In this picture, the four-zero texture is desirable for realistic masses and mixings. This texture is realized by a specific representation for the second breaking of the S3 L×S3 R flavor symmetry. Assuming only renormalizable Yukawa interactions, type-I seesaw mechanism, and neglecting C P phases for simplicity, the right-handed neutrino mass matrix MR can be reconstructed from low energy input values. Numerical analysis shows that the texture of MR basically behaves like the "waterfall texture." Since MR tends to be the "cascade texture" in the democratic texture approach, a model with type-I seesaw and up-type Yukawa unification Yν≃Yu basically requires fine-tunings between parameters. Therefore, it seems to be more realistic to consider universal waterfall textures for both Yf and MR, e.g., by the radiative mass generation or the Froggatt-Nielsen mechanism. Moreover, analysis of eigenvalues shows that the lightest mass eigenvalue MR 1 is too light to achieve successful thermal leptogenesis. Although the resonant leptogenesis might be possible, it also requires fine-tunings of parameters.

SU(3)_C× SU(2)_L× U(1)_Y( × U(1)_X ) as a symmetry of division algebraic ladder operators

NASA Astrophysics Data System (ADS)

Furey, C.

2018-05-01

We demonstrate a model which captures certain attractive features of SU(5) theory, while providing a possible escape from proton decay. In this paper we show how ladder operators arise from the division algebras R, C, H, and O. From the SU( n) symmetry of these ladder operators, we then demonstrate a model which has much structural similarity to Georgi and Glashow's SU(5) grand unified theory. However, in this case, the transitions leading to proton decay are expected to be blocked, given that they coincide with presumably forbidden transformations which would incorrectly mix distinct algebraic actions. As a result, we find that we are left with G_{sm} = SU(3)_C× SU(2)_L× U(1)_Y / Z_6. Finally, we point out that if U( n) ladder symmetries are used in place of SU( n), it may then be possible to find this same G_{sm}=SU(3)_C× SU(2)_L× U(1)_Y / Z_6, together with an extra U(1)_X symmetry, related to B-L.

Novel symmetries in Weyl-invariant gravity with massive gauge field

NASA Astrophysics Data System (ADS)

Abhinav, K.; Shukla, A.; Panigrahi, P. K.

2016-11-01

The background field method is used to linearize the Weyl-invariant scalar-tensor gravity, coupled with a Stückelberg field. For a generic background metric, this action is found not to be invariant, under both a diffeomorphism and generalized Weyl symmetry, the latter being a combination of gauge and Weyl transformations. Interestingly, the quadratic Lagrangian, emerging from a background of Minkowski metric, respects both transformations independently. The Becchi-Rouet-Stora-Tyutin symmetry of scalar-tensor gravity coupled with a Stückelberg-like massive gauge particle, possessing a diffeomorphism and generalized Weyl symmetry, reveals that in both cases negative-norm states with unphysical degrees of freedom do exist. We then show that, by combining diffeomorphism and generalized Weyl symmetries, all the ghost states decouple, thereby removing the unphysical redundancies of the theory. During this process, the scalar field does not represent any dynamic mode, yet modifies the usual harmonic gauge condition through non-minimal coupling with gravity.

Spontaneous mirror left-right symmetry breaking for leptogenesis parametrized by Majorana neutrino mass matrix

NASA Astrophysics Data System (ADS)

Gu, Pei-Hong

2017-10-01

We introduce a mirror copy of the ordinary fermions and Higgs scalars for embedding the SU(2) L × U(1) Y electroweak gauge symmetry into an SU(2) L × SU(2) R × U(1) B-L left-right gauge symmetry. We then show the spontaneous left-right symmetry breaking can automatically break the parity symmetry motivated by solving the strong CP problem. Through the SU(2) R gauge interactions, a mirror Majorana neutrino can decay into a mirror charged lepton and two mirror quarks. Consequently we can obtain a lepton asymmetry stored in the mirror charged leptons. The Yukawa couplings of the mirror and ordinary charged fermions to a dark matter scalar then can transfer the mirror lepton asymmetry to an ordinary lepton asymmetry which provides a solution to the cosmic baryon asymmetry in association with the SU(2) L sphaleron processes. In this scenario, the baryon asymmetry can be well described by the neutrino mass matrix up to an overall factor.

Dark matter and gauged flavor symmetries

DOE PAGES

Bishara, Fady; Greljo, Admir; Kamenik, Jernej F.; ...

2015-12-21

We investigate the phenomenology of flavored dark matter (DM). DM stability is guaranteed by an accidental Z 3 symmetry, a subgroup of the standard model (SM) flavor group that is not broken by the SM Yukawa interactions. We consider an explicit realization where the quark part of the SM flavor group is fully gauged. If the dominant interactions between DM and visible sector are through flavor gauge bosons, as we show for Dirac fermion flavored DM, then the DM mass is bounded between roughly 0.5 TeV and 5 TeV if the DM multiplet mass is split only radiatively. In general,more » however, no such relation exists. We demonstrate this using scalar flavored DM where the main interaction with the SM is through the Higgs portal. For both cases we derive constraints from flavor, cosmology, direct and indirect DM detection, and collider searches.« less

Dark matter and gauged flavor symmetries

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bishara, Fady; Greljo, Admir; Kamenik, Jernej F.

We investigate the phenomenology of flavored dark matter (DM). DM stability is guaranteed by an accidental Z 3 symmetry, a subgroup of the standard model (SM) flavor group that is not broken by the SM Yukawa interactions. We consider an explicit realization where the quark part of the SM flavor group is fully gauged. If the dominant interactions between DM and visible sector are through flavor gauge bosons, as we show for Dirac fermion flavored DM, then the DM mass is bounded between roughly 0.5 TeV and 5 TeV if the DM multiplet mass is split only radiatively. In general,more » however, no such relation exists. We demonstrate this using scalar flavored DM where the main interaction with the SM is through the Higgs portal. For both cases we derive constraints from flavor, cosmology, direct and indirect DM detection, and collider searches.« less

Projected Entangled Pair States with non-Abelian gauge symmetries: An SU(2) study

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zohar, Erez, E-mail: erez.zohar@mpq.mpg.de; Wahl, Thorsten B.; Burrello, Michele, E-mail: michele.burrello@mpq.mpg.de

Over the last years, Projected Entangled Pair States have demonstrated great power for the study of many body systems, as they naturally describe ground states of gapped many body Hamiltonians, and suggest a constructive way to encode and classify their symmetries. The PEPS study is not only limited to global symmetries, but has also been extended and applied for local symmetries, allowing to use them for the description of states in lattice gauge theories. In this paper we discuss PEPS with a local, SU(2) gauge symmetry, and demonstrate the use of PEPS features and techniques for the study of amore » simple family of many body states with a non-Abelian gauge symmetry. We present, in particular, the construction of fermionic PEPS able to describe both two-color fermionic matter and the degrees of freedom of an SU(2) gauge field with a suitable truncation.« less

The role of gauge symmetry in spintronics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sobreiro, R.F., E-mail: sobreiro@if.uff.br; Vasquez Otoya, V.J.

2011-12-15

In this work we employ a field theoretical approach to explain the nature of the non-conserved spin current in spintronics. In particular, we consider the usual U(1) gauge theory for the electromagnetism at classical level in order to obtain the broken continuity equation involving the spin current and spin-transfer torque. Inspired by the recent work of A. Vernes, B. L. Gyorffy and P. Weinberger where they obtain such an equation in terms of relativistic quantum mechanics, we formalize their result in terms of the well known currents of field theory such as the Bargmann-Wigner current and the chiral current. Thus,more » an interpretation of spintronics is provided in terms of Noether currents (conserved or not) and symmetries of the electromagnetism. In fact, the main result of the present work is that the non-conservation of the spin current is associated with the gauge invariance of physical observables where the breaking term is proportional to the chiral current. Moreover, we generalize their result by including the electromagnetic field as a dynamical field instead of an external one.« less

Holism and structuralism in U(1) gauge theory

NASA Astrophysics Data System (ADS)

Lyre, Holger

After decades of neglect philosophers of physics have discovered gauge theories-arguably the paradigm of modern field physics-as a genuine topic for foundational and philosophical research. Incidentally, in the last couple of years interest from the philosophy of physics in structural realism-in the eyes of its proponents the best suited realist position towards modern physics-has also raised. This paper tries to connect both topics and aims to show that structural realism gains further credence from an ontological analysis of gauge theories-in particular U (1) gauge theory. In the first part of the paper the framework of fiber bundle gauge theories is briefly presented and the interpretation of local gauge symmetry will be examined. In the second part, an ontological underdetermination of gauge theories is carved out by considering the various kinds of non-locality involved in such typical effects as the Aharonov-Bohm effect. The analysis shows that the peculiar form of non-separability figuring in gauge theories is a variant of spatiotemporal holism and can be distinguished from quantum theoretic holism. In the last part of the paper the arguments for a gauge theoretic support of structural realism are laid out and discussed.

Discrete symmetries in Heterotic/F-theory duality and mirror symmetry

DOE PAGES

Cvetič, Mirjam; Grassi, Antonella; Poretschkin, Maximilian

2017-06-30

We study aspects of Heterotic/F-theory duality for compacti cations with Abelian discrete gauge symmetries. We consider F-theory compacti cations on genus-one bered Calabi-Yau manifolds with n-sections, associated with the Tate-Shafarevich group Z n. Such models are obtained by studying rst a speci c toric set-up whose associated Heterotic vector bundle has structure group Z n. By employing a conjectured Heterotic/Ftheory mirror symmetry we construct dual geometries of these original toric models, where in the stable degeneration limit we obtain a discrete gauge symmetry of order two and three, for compacti cations to six dimensions. We provide explicit constructions of mirrorpairsmore » for symmetric examples with Z 2 and Z 3, in six dimensions. The Heterotic models with symmetric discrete symmetries are related in eld theory to a Higgsing of Heterotic models with two symmetric abelian U(1) gauge factors, where due to the Stuckelberg mechanism only a diagonal U(1) factor remains massless, and thus after Higgsing only a diagonal discrete symmetry of order n is present in the Heterotic models and detected via Heterotic/F-theory duality. These constructions also provide further evidence for the conjectured mirror symmetry in Heterotic/F-theory at the level of brations with torsional sections and those with multi-sections.« less

Discrete symmetries in Heterotic/F-theory duality and mirror symmetry

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cvetič, Mirjam; Grassi, Antonella; Poretschkin, Maximilian

We study aspects of Heterotic/F-theory duality for compacti cations with Abelian discrete gauge symmetries. We consider F-theory compacti cations on genus-one bered Calabi-Yau manifolds with n-sections, associated with the Tate-Shafarevich group Z n. Such models are obtained by studying rst a speci c toric set-up whose associated Heterotic vector bundle has structure group Z n. By employing a conjectured Heterotic/Ftheory mirror symmetry we construct dual geometries of these original toric models, where in the stable degeneration limit we obtain a discrete gauge symmetry of order two and three, for compacti cations to six dimensions. We provide explicit constructions of mirrorpairsmore » for symmetric examples with Z 2 and Z 3, in six dimensions. The Heterotic models with symmetric discrete symmetries are related in eld theory to a Higgsing of Heterotic models with two symmetric abelian U(1) gauge factors, where due to the Stuckelberg mechanism only a diagonal U(1) factor remains massless, and thus after Higgsing only a diagonal discrete symmetry of order n is present in the Heterotic models and detected via Heterotic/F-theory duality. These constructions also provide further evidence for the conjectured mirror symmetry in Heterotic/F-theory at the level of brations with torsional sections and those with multi-sections.« less

Toward electroweak scale cold dark matter with local dark gauge symmetry and beyond the DM EFT

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ko, Pyungwon, E-mail: pko@kias.re.kr

2016-06-21

In this talk, I describe a class of electroweak (EW) scale dark matter (DM) models where its stability or longevity are the results of underlying dark gauge symmetries: stable due to unbroken local dark gauge symmetry or topology, or long-lived due to the accidental global symmetry of dark gauge theories. Compared with the usual phenomenological dark matter models (including DM EFT or simplified DM models), DM models with local dark gauge symmetries include dark gauge bosons, dark Higgs bosons and sometimes excited dark matter. And dynamics among these fields are completely fixed by local gauge principle. The idea of singletmore » portals including the Higgs portal can thermalize these hidden sector dark matter very efficiently, so that these DM could be easily thermal DM. I also discuss the limitation of the usual DM effective field theory or simplified DM models without the full SM gauge symmetry, and emphasize the importance of the full SM gauge symmetry and renormalizability especially for collider searches for DM.« less

Gauged Q-balls

NASA Technical Reports Server (NTRS)

Lee, Kimyeong; Stein-Schabes, Jaime A.; Watkins, Richard; Widrow, Lawrence M.

1988-01-01

Classical non-topological soliton configurations are considered within the theory of a complex scalar field with a gauged U symmetry. Their existence and stability against dispersion are demonstrated and some of their properties are investigated analytically and numerically. The soliton configuration is such that inside the soliton the local U symmetry is broken, the gauge field becomes massive and for a range of values of the coupling constants the soliton becomes a superconductor pushing the charge to the surface. Furthermore, because of the repulsive Coulomb force, there is a maximum size for these objects, making impossible the existence of Q-matter in bulk form. Also briefly discussed are solitons with fermions in a U gauge theory.

Radiatively induced neutrino mass model with flavor dependent gauge symmetry

NASA Astrophysics Data System (ADS)

Lee, SangJong; Nomura, Takaaki; Okada, Hiroshi

2018-06-01

We study a radiative seesaw model at one-loop level with a flavor dependent gauge symmetry U(1) μ - τ, in which we consider bosonic dark matter. We also analyze the constraints from lepton flavor violations, muon g - 2, relic density of dark matter, and collider physics, and carry out numerical analysis to search for allowed parameter region which satisfy all the constraints and to investigate some predictions. Furthermore we find that a simple but adhoc hypothesis induces specific two zero texture with inverse mass matrix, which provides us several predictions such as a specific pattern of Dirac CP phase.

Symmetries in Physics

NASA Astrophysics Data System (ADS)

Brading, Katherine; Castellani, Elena

2010-01-01

Preface; Copyright acknowledgements; List of contributors; 1. Introduction; Part I. Continuous Symmetries: 2. Classic texts: extracts from Weyl and Wigner; 3. Review paper: On the significance of continuous symmetry to the foundations of physics C. Martin; 4. The philosophical roots of the gauge principle: Weyl and transcendental phenomenological idealism T. Ryckman; 5. Symmetries and Noether's theorems K. A. Brading and H. R. Brown; 6. General covariance, gauge theories, and the Kretschmann objection J. Norton; 7. The interpretation of gauge symmetry M. Redhead; 8. Tracking down gauge: an ode to the constrained Hamiltonian formalism J. Earman; 9. Time-dependent symmetries: the link between gauge symmetries and indeterminism D. Wallace; 10. A fourth way to the Aharanov-Bohm effect A. Nounou; Part II. Discrete Symmetries: 11. Classic texts: extracts from Lebniz, Kant and Black; 12. Review paper: Understanding permutation symmetry S. French and D. Rickles; 13. Quarticles and the identity of discernibles N. Hugget; 14. Review paper: Handedness, parity violation, and the reality of space O. Pooley; 15. Mirror symmetry: what is it for a relational space to be orientable? N. Huggett; 16. Physics and Leibniz's principles S. Saunders; Part III. Symmetry Breaking: 17: Classic texts: extracts from Curie and Weyl; 18. Extract from G. Jona-Lasinio: Cross-fertilization in theoretical physics: the case of condensed matter and particle physics G. Jona-Lasinio; 19. Review paper: On the meaning of symmetry breaking E. Castellani; 20. Rough guide to spontaneous symmetry breaking J. Earman; 21. Spontaneous symmetry breaking: theoretical arguments and philosophical problems M. Morrison; Part IV. General Interpretative Issues: 22. Classic texts: extracts from Wigner; 23. Symmetry as a guide to superfluous theoretical structure J. Ismael and B. van Fraassen; 24. Notes on symmetries G. Belot; 25. Symmetry, objectivity, and design P. Kosso; 26. Symmetry and equivalence E. Castellani.

Symmetries in Physics

NASA Astrophysics Data System (ADS)

Brading, Katherine; Castellani, Elena

2003-12-01

Preface; Copyright acknowledgements; List of contributors; 1. Introduction; Part I. Continuous Symmetries: 2. Classic texts: extracts from Weyl and Wigner; 3. Review paper: On the significance of continuous symmetry to the foundations of physics C. Martin; 4. The philosophical roots of the gauge principle: Weyl and transcendental phenomenological idealism T. Ryckman; 5. Symmetries and Noether's theorems K. A. Brading and H. R. Brown; 6. General covariance, gauge theories, and the Kretschmann objection J. Norton; 7. The interpretation of gauge symmetry M. Redhead; 8. Tracking down gauge: an ode to the constrained Hamiltonian formalism J. Earman; 9. Time-dependent symmetries: the link between gauge symmetries and indeterminism D. Wallace; 10. A fourth way to the Aharanov-Bohm effect A. Nounou; Part II. Discrete Symmetries: 11. Classic texts: extracts from Lebniz, Kant and Black; 12. Review paper: Understanding permutation symmetry S. French and D. Rickles; 13. Quarticles and the identity of discernibles N. Hugget; 14. Review paper: Handedness, parity violation, and the reality of space O. Pooley; 15. Mirror symmetry: what is it for a relational space to be orientable? N. Huggett; 16. Physics and Leibniz's principles S. Saunders; Part III. Symmetry Breaking: 17: Classic texts: extracts from Curie and Weyl; 18. Extract from G. Jona-Lasinio: Cross-fertilization in theoretical physics: the case of condensed matter and particle physics G. Jona-Lasinio; 19. Review paper: On the meaning of symmetry breaking E. Castellani; 20. Rough guide to spontaneous symmetry breaking J. Earman; 21. Spontaneous symmetry breaking: theoretical arguments and philosophical problems M. Morrison; Part IV. General Interpretative Issues: 22. Classic texts: extracts from Wigner; 23. Symmetry as a guide to superfluous theoretical structure J. Ismael and B. van Fraassen; 24. Notes on symmetries G. Belot; 25. Symmetry, objectivity, and design P. Kosso; 26. Symmetry and equivalence E. Castellani.

Light Higgsino and gluino in R-invariant direct Gauge mediation

NASA Astrophysics Data System (ADS)

Nagai, Ryo; Yokozaki, Norimi

2018-03-01

We provide a simple solution to the μ-Bμ problem in the "R-invariant direct gauge mediation model". With the solution, the Higgsino and gluino are predicted to be light as O (100) GeV and O (1) TeV, respectively. Those gluino and Higgsino can be accessible at the LHC and future collider experiments. Moreover, dangerous dimension five operators inducing rapid proton decays are naturally suppressed by the R-symmetry.

Lusztig symmetries and Poincare-Birkhoff-Witt basis for wU{sub r,s}{sup d}(osp(1|2n))

DOE Office of Scientific and Technical Information (OSTI.GOV)

Liu, Junli; College of Applied Sciences, Beijing University of Technology, Beijing 100124; Yang, Shilin

2013-12-15

We investigate a new kind of two-parameter weak quantized superalgebra wU{sub r,s}{sup d}(osp(1|2n)), which is a weak Hopf superalgebra. It has a homomorphic image which is isomorphic to the usual two-parameter quantum superalgebra U{sub r,s}(osp(1|2n)) of osp(1|2n). We also discuss the basis of wU{sub r,s}{sup d}(osp(1|2n)) by Lusztig's symmetries.

Spontaneous SUSY breaking without R symmetry in supergravity

NASA Astrophysics Data System (ADS)

Maekawa, Nobuhiro; Omura, Yuji; Shigekami, Yoshihiro; Yoshida, Manabu

2018-03-01

We discuss spontaneous supersymmetry (SUSY) breaking in a model with an anomalous U (1 )A symmetry. In this model, the size of the each term in the superpotential is controlled by the U (1 )A charge assignment and SUSY is spontaneously broken via the Fayet-Iliopoulos of U (1 )A at the metastable vacuum. In the global SUSY analysis, the gaugino masses become much smaller than the sfermion masses, because an approximate R symmetry appears at the SUSY breaking vacuum. In this paper, we show that gaugino masses can be as large as gravitino mass, taking the supergravity effect into consideration. This is because the R symmetry is not imposed so that the constant term in the superpotential, which is irrelevant to the global SUSY analysis, largely contributes to the soft SUSY breaking terms in the supergravity. As the mediation mechanism, we introduce the contributions of the field not charged under U (1 )A and the moduli field to cancel the anomaly of U (1 )A. We comment on the application of our SUSY breaking scenario to the grand unified theory.

Cellular gauge symmetry and the Li organization principle: General considerations.

PubMed

Tozzi, Arturo; Peters, James F; Navarro, Jorge; Kun, Wu; Lin, Bi; Marijuán, Pedro C

2017-12-01

Based on novel topological considerations, we postulate a gauge symmetry for living cells and proceed to interpret it from a consistent Eastern perspective: the li organization principle. In our framework, the reference system is the living cell, equipped with general symmetries and energetic constraints standing for the intertwined biochemical, metabolic and signaling pathways that allow the global homeostasis of the system. Environmental stimuli stand for forces able to locally break the symmetry of metabolic/signaling pathways, while the species-specific DNA is the gauge field that restores the global homeostasis after external perturbations. We apply the Borsuk-Ulam Theorem (BUT) to operationalize a methodology in terms of topology/gauge fields and subsequently inquire about the evolution from inorganic to organic structures and to the prokaryotic and eukaryotic modes of organization. We converge on the strategic role that second messengers have played regarding the emergence of a unitary gauge field with profound evolutionary implications. A new avenue for a deeper investigation of biological complexity looms. Philosophically, we might be reminded of the duality between two essential concepts proposed by the great Chinese synthesizer Zhu Xi (in the XIII Century). On the one side the li organization principle, equivalent to the dynamic interplay between symmetry and information; and on the other side the qi principle, equivalent to the energy participating in the process-both always interlinked with each other. In contemporary terms, it would mean the required interconnection between information and energy, and the necessity to revise essential principles of information philosophy. Copyright © 2017 Elsevier Ltd. All rights reserved.

Gauging Spatial Symmetries and the Classification of Topological Crystalline Phases

NASA Astrophysics Data System (ADS)

Thorngren, Ryan; Else, Dominic V.

2018-01-01

We put the theory of interacting topological crystalline phases on a systematic footing. These are topological phases protected by space-group symmetries. Our central tool is an elucidation of what it means to "gauge" such symmetries. We introduce the notion of a crystalline topological liquid and argue that most (and perhaps all) phases of interest are likely to satisfy this criterion. We prove a crystalline equivalence principle, which states that in Euclidean space, crystalline topological liquids with symmetry group G are in one-to-one correspondence with topological phases protected by the same symmetry G , but acting internally, where if an element of G is orientation reversing, it is realized as an antiunitary symmetry in the internal symmetry group. As an example, we explicitly compute, using group cohomology, a partial classification of bosonic symmetry-protected topological phases protected by crystalline symmetries in (3 +1 ) dimensions for 227 of the 230 space groups. For the 65 space groups not containing orientation-reversing elements (Sohncke groups), there are no cobordism invariants that may contribute phases beyond group cohomology, so we conjecture that our classification is complete.

Various Forms of BRST Symmetry in Abelian 2-FORM Gauge Theory

NASA Astrophysics Data System (ADS)

Rai, Sumit Kumar; Mandal, Bhabani Prasad

We derive the various forms of BRST symmetry using Batalin-Fradkin-Vilkovisky approach in the case of Abelian 2-form gauge theory. We show that the so-called dual BRST symmetry is not an independent symmetry but the generalization of BRST symmetry obtained from the canonical transformation in the bosonic and ghost sector. We further obtain the new forms of both BRST and dual-BRST symmetry by making a general transformation in the Lagrange multipliers of the bosonic and ghost sector of the theory.

Zee-Babu type model with U (1 )Lμ-Lτ gauge symmetry

NASA Astrophysics Data System (ADS)

Nomura, Takaaki; Okada, Hiroshi

2018-05-01

We extend the Zee-Babu model, introducing local U (1 )Lμ-Lτ symmetry with several singly charged bosons. We find a predictive neutrino mass texture in a simple hypothesis in which mixings among singly charged bosons are negligible. Also, lepton-flavor violations are less constrained compared with the original model. Then, we explore the testability of the model, focusing on doubly charged boson physics at the LHC and the International Linear Collider.

Composite particle theory of three-dimensional gapped fermionic phases: Fractional topological insulators and charge-loop excitation symmetry

NASA Astrophysics Data System (ADS)

Ye, Peng; Hughes, Taylor L.; Maciejko, Joseph; Fradkin, Eduardo

2016-09-01

Topological phases of matter are usually realized in deconfined phases of gauge theories. In this context, confined phases with strongly fluctuating gauge fields seem to be irrelevant to the physics of topological phases. For example, the low-energy theory of the two-dimensional (2D) toric code model (i.e., the deconfined phase of Z2 gauge theory) is a U(1 )×U(1 ) Chern-Simons theory in which gauge charges (i.e., e and m particles) are deconfined and the gauge fields are gapped, while the confined phase is topologically trivial. In this paper, we point out a route to constructing exotic three-dimensional (3D) gapped fermionic phases in a confining phase of a gauge theory. Starting from a parton construction with strongly fluctuating compact U(1 )×U(1 ) gauge fields, we construct gapped phases of interacting fermions by condensing two linearly independent bosonic composite particles consisting of partons and U(1 )×U(1 ) magnetic monopoles. This can be regarded as a 3D generalization of the 2D Bais-Slingerland condensation mechanism. Charge fractionalization results from a Debye-Hückel-type screening cloud formed by the condensed composite particles. Within our general framework, we explore two aspects of symmetry-enriched 3D Abelian topological phases. First, we construct a new fermionic state of matter with time-reversal symmetry and Θ ≠π , the fractional topological insulator. Second, we generalize the notion of anyonic symmetry of 2D Abelian topological phases to the charge-loop excitation symmetry (Charles ) of 3D Abelian topological phases. We show that line twist defects, which realize Charles transformations, exhibit non-Abelian fusion properties.

Phenomenology of the SU(3)_c⊗ SU(3)_L⊗ U(1)_X model with right-handed neutrinos

NASA Astrophysics Data System (ADS)

Gutiérrez, D. A.; Ponce, W. A.; Sánchez, L. A.

2006-05-01

A phenomenological analysis of the three-family model based on the local gauge group SU(3)_c⊗ SU(3)_L⊗ U(1)_X with right-handed neutrinos is carried out. Instead of using the minimal scalar sector able to break the symmetry in a proper way, we introduce an alternative set of four Higgs scalar triplets, which combined with an anomaly-free discrete symmetry, produces a quark mass spectrum without hierarchies in the Yukawa coupling constants. We also embed the structure into a simple gauge group and show some conditions for achieving a low energy gauge coupling unification, avoiding possible conflict with proton decay bounds. By using experimental results from the CERN-LEP, SLAC linear collider, and atomic parity violation data, we update constraints on several parameters of the model.

Phenomenology of the SU(3)c⊗SU(3)L⊗U(1)X model with exotic charged leptons

NASA Astrophysics Data System (ADS)

Salazar, Juan C.; Ponce, William A.; Gutiérrez, Diego A.

2007-04-01

A phenomenological analysis of the three-family model based on the local gauge group SU(3)c⊗SU(3)L⊗U(1)X with exotic charged leptons, is carried out. Instead of using the minimal scalar sector able to break the symmetry in a proper way, we introduce an alternative set of four Higgs scalar triplets, which combined with an anomaly-free discrete symmetry, produce quark and charged lepton mass spectrum without hierarchies in the Yukawa coupling constants. We also embed the structure into a simple gauge group and show some conditions to achieve a low energy gauge coupling unification, avoiding possible conflict with proton decay bounds. By using experimental results from the CERN-LEP, SLAC linear collider, and atomic parity violation data, we update constraints on several parameters of the model.

Clash of symmetries in a Randall-Sundrum-like spacetime

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dando, Gareth; George, Damien P.; Volkas, Raymond R.

2005-08-15

We present a toy model that exhibits clash-of-symmetries style Higgs field kink configurations in a Randall-Sundrum-like spacetime. The model has two complex scalar fields {phi}{sub 1,2}, with a sextic potential obeying global U(1)xU(1) and discrete {phi}{sub 1}{r_reversible}{phi}{sub 2} interchange symmetries. The scalar fields are coupled to 4+1 dimensional gravity endowed with a bulk cosmological constant. We show that the coupled Einstein-Higgs field equations have an interesting analytic solution provided the sextic potential adopts a particular form. The 4+1 metric is shown to be that of a smoothed-out Randall-Sundrum type of spacetime. The thin-brane Randall-Sundrum limit, whereby the Higgs field kinksmore » become step functions, is carefully defined in terms of the fundamental parameters in the action. The 'clash-of-symmetries' feature, defined in previous papers, is manifested here through the fact that both of the U(1) symmetries are spontaneously broken at all nonasymptotic points in the extra dimension w. One of the U(1)'s is asymptotically restored as w{yields}-{infinity}, with the other U(1) restored as w{yields}+{infinity}. The spontaneously broken discrete symmetry ensures topological stability. In the gauged version of this model we find new flat-space solutions, but in the warped metric case we have been unable to find any solutions with nonzero gauge fields.« less

Dynamical symmetry enhancement near N = 2, D = 4 gauged supergravity horizons

NASA Astrophysics Data System (ADS)

Gutowski, J.; Mohaupt, T.; Papadopoulos, G.

2017-03-01

We show that all smooth Killing horizons with compact horizon sections of 4-dimensional gauged N = 2 supergravity coupled to any number of vector multiplets preserve 2{c}_1(K)+4ℓ supersymmetries, where K is a pull-back of the Hodge bundle of the special Kähler manifold on the horizon spatial section. We also demonstrate that all such horizons with {c}_1(K)=0 exhibit an sl(2,R) symmetry and preserve either 4 or 8 supersymmetries. If the orbits of the sl(2,R) symmetry are 2-dimensional, the horizons are warped products of AdS2 with the horizon spatial section. Otherwise, the horizon section admits an isometry which preserves all the fields. The proof of these results is centered on the use of index theorem in conjunction with an appropriate generalization of the Lichnerowicz theorem for horizons that preserve at least one supersymmetry. In all {c}_1(K)=0 cases, we specify the local geometry of spatial horizon sections and demonstrate that the solutions are determined by first order non-linear ordinary differential equations on some of the fields.

Hidden conformal symmetry of rotating black holes in minimal five-dimensional gauged supergravity

DOE Office of Scientific and Technical Information (OSTI.GOV)

Setare, M. R.; Kamali, V.

2010-10-15

In the present paper we show that for a low frequency limit the wave equation of a massless scalar field in the background of nonextremal charged rotating black holes in five-dimensional minimal gauged and ungauged supergravity can be written as the Casimir of an SL(2,R) symmetry. Our result shows that the entropy of the black hole is reproduced by the Cardy formula. Also the absorption cross section is consistent with the finite temperature absorption cross section for a two-dimensional conformal field theory.

Origin of Abelian gauge symmetries in heterotic/F-theory duality

DOE PAGES

Cvetič, Mirjam; Grassi, Antonella; Klevers, Denis; ...

2016-04-07

Here, we study aspects of heterotic/F-theory duality for compactifications with Abelian gauge symmetries. We consider F-theory on general Calabi-Yau manifolds with a rank one Mordell-Weil group of rational sections. By rigorously performing the stable degeneration limit in a class of toric models, and also derive both the Calabi-Yau geometry and the spectral cover describing the vector bundle in the heterotic dual theory. We carefully investigate the spectral cover employing the group law on the elliptic curve in the heterotic theory. We find in explicit examples that there are three different classes of heterotic duals that have U(1) factors in theirmore » low energy effective theories: split spectral covers describing bundles with S(U(m) x U(1)) structure group, spectral covers containing torsional sections that seem to give rise to bundles with SU(m) x Z_k structure group and bundles with purely non-Abelian structure groups having a centralizer in E_8 containing a U(1) factor. In the former two cases, it is required that the elliptic fibration on the heterotic side has a non-trivial Mordell-Weil group. And while the number of geometrically massless U(1)'s is determined entirely by geometry on the F-theory side, on the heterotic side the correct number of U(1)'s is found by taking into account a Stuckelberg mechanism in the lower-dimensional effective theory. Finally, in geometry, this corresponds to the condition that sections in the two half K3 surfaces that arise in the stable degeneration limit of F-theory can be glued together globally.« less

Quark seesaw mechanism, dark U (1 ) symmetry, and the baryon-dark matter coincidence

NASA Astrophysics Data System (ADS)

Gu, Pei-Hong; Mohapatra, Rabindra N.

2017-09-01

We attempt to understand the baryon-dark matter coincidence problem within the quark seesaw extension of the standard model where parity invariance is used to solve the strong C P problem. The S U (2 )L×S U (2 )R×U (1 )B -L gauge symmetry of this model is extended by a dark U (1 )X group plus inclusion of a heavy neutral vector-like fermion χL ,R charged under the dark group which plays the role of dark matter. All fermions are Dirac type in this model. Decay of heavy scalars charged under U (1 )X leads to simultaneous asymmetry generation of the dark matter and baryons after sphaleron effects are included. The U (1 )X group not only helps to stabilize the dark matter but also helps in the elimination of the symmetric part of the dark matter via χ -χ ¯ annihilation. For dark matter mass near the proton mass, it explains why the baryon and dark matter abundances are of similar magnitude (the baryon-dark matter coincidence problem). This model is testable in low threshold (sub-keV) direct dark matter search experiments.

Duality, Gauge Symmetries, Renormalization Groups and the BKT Transition

NASA Astrophysics Data System (ADS)

José, Jorge V.

2017-03-01

In this chapter, I will briefly review, from my own perspective, the situation within theoretical physics at the beginning of the 1970s, and the advances that played an important role in providing a solid theoretical and experimental foundation for the Berezinskii-Kosterlitz-Thouless theory (BKT). Over this period, it became clear that the Abelian gauge symmetry of the 2D-XY model had to be preserved to get the right phase structure of the model. In previous analyses, this symmetry was broken when using low order calculational approximations. Duality transformations at that time for two-dimensional models with compact gauge symmetries were introduced by José, Kadanoff, Nelson and Kirkpatrick (JKKN). Their goal was to analyze the phase structure and excitations of XY and related models, including symmetry breaking fields which are experimentally important. In a separate context, Migdal had earlier developed an approximate Renormalization Group (RG) algorithm to implement Wilson’s RG for lattice gauge theories. Although Migdal’s RG approach, later extended by Kadanoff, did not produce a true phase transition for the XY model, it almost did asymptotically in terms of a non-perturbative expansion in the coupling constant with an essential singularity. Using these advances, including work done on instantons (vortices), JKKN analyzed the behavior of the spin-spin correlation functions of the 2D XY-model in terms of an expansion in temperature and vortex-pair fugacity. Their analysis led to a perturbative derivation of RG equations for the XY model which are the same as those first derived by Kosterlitz for the two-dimensional Coulomb gas. JKKN’s results gave a theoretical formulation foundation and justification for BKT’s sound physical assumptions and for the validity of their calculational approximations that were, in principle, strictly valid only at very low temperatures, away from the critical TBKT temperature. The theoretical predictions were soon tested

Duality, Gauge Symmetries, Renormalization Groups and the BKT Transition

NASA Astrophysics Data System (ADS)

José, Jorge V.

2013-06-01

In this chapter, I will briefly review, from my own perspective, the situation within theoretical physics at the beginning of the 1970s, and the advances that played an important role in providing a solid theoretical and experimental foundation for the Berezinskii-Kosterlitz-Thouless theory (BKT). Over this period, it became clear that the Abelian gauge symmetry of the 2D-XY model had to be preserved to get the right phase structure of the model. In previous analyses, this symmetry was broken when using low order calculational approximations. Duality transformations at that time for two-dimensional models with compact gauge symmetries were introduced by José, Kadanoff, Nelson and Kirkpatrick (JKKN). Their goal was to analyze the phase structure and excitations of XY and related models, including symmetry breaking fields which are experimentally important. In a separate context, Migdal had earlier developed an approximate Renormalization Group (RG) algorithm to implement Wilson's RG for lattice gauge theories. Although Migdal's RG approach, later extended by Kadanoff, did not produce a true phase transition for the XY model, it almost did asymptotically in terms of a non-perturbative expansion in the coupling constant with an essential singularity. Using these advances, including work done on instantons (vortices), JKKN analyzed the behavior of the spin-spin correlation functions of the 2D XY-model in terms of an expansion in temperature and vortex-pair fugacity. Their analysis led to a perturbative derivation of RG equations for the XY model which are the same as those first derived by Kosterlitz for the two-dimensional Coulomb gas. JKKN's results gave a theoretical formulation foundation and justification for BKT's sound physical assumptions and for the validity of their calculational approximations that were, in principle, strictly valid only at very low temperatures, away from the critical TBKT temperature. The theoretical predictions were soon tested

Gauged U(1) clockwork theory

NASA Astrophysics Data System (ADS)

Lee, Hyun Min

2018-03-01

We consider the gauged U (1) clockwork theory with a product of multiple gauge groups and discuss the continuum limit of the theory to a massless gauged U (1) with linear dilaton background in five dimensions. The localization of the lightest state of gauge fields on a site in the theory space naturally leads to exponentially small effective couplings of external matter fields localized away from the site. We discuss the implications of our general discussion with some examples, such as mediators of dark matter interactions, flavor-changing B-meson decays as well as D-term SUSY breaking.

Analytic topologically nontrivial solutions of the (3 +1 )-dimensional U (1 ) gauged Skyrme model and extended duality

NASA Astrophysics Data System (ADS)

Avilés, L.; Canfora, F.; Dimakis, N.; Hidalgo, D.

2017-12-01

We construct the first analytic examples of topologically nontrivial solutions of the (3 +1 )-dimensional U (1 ) gauged Skyrme model within a finite box in (3 +1 )-dimensional flat space-time. There are two types of gauged solitons. The first type corresponds to gauged Skyrmions living within a finite volume. The second corresponds to gauged time crystals (smooth solutions of the U (1 ) gauged Skyrme model whose periodic time dependence is protected by a winding number). The notion of electromagnetic duality can be extended for these two types of configurations in the sense that the electric and one of the magnetic components can be interchanged. These analytic solutions show very explicitly the Callan-Witten mechanism (according to which magnetic monopoles may "swallow" part of the topological charge of the Skyrmion) since the electromagnetic field contributes directly to the conserved topological charge of the gauged Skyrmions. As it happens in superconductors, the magnetic field is suppressed in the core of the gauged Skyrmions. On the other hand, the electric field is strongly suppresed in the core of gauged time crystals.

Broken SU(3) x SU(3) x SU(3) x SU(3) Symmetry

DOE R&D Accomplishments Database

Freund, P. G. O.; Nambu, Y.

1964-10-01

We argue that the "Eight-fold Way" version of the SU(3) symmetry should be extended to a product of up to four separate and badly broken SU(3) groups, including the gamma{sub 5} type SU(3) symmetry. A hierarchy of subgroups (or subalgebras) are considered within this framework, and two candidates are found to be interesting in view of experimental evidence. Main features of the theory are: 1) the baryons belong to a nonet; 2) there is an octet of axial vector gauge mesons in addition to one or two octets of vector mesons; 3) pseudoscalar and scalar mesons exist as "incomplete" multiplets arising from spontaneous breakdown of symmetry.

Instanton operators and symmetry enhancement in 5d supersymmetric quiver gauge theories

NASA Astrophysics Data System (ADS)

Yonekura, Kazuya

2015-07-01

We consider general 5d SU( N ) quiver gauge theories whose nodes form an ADE Dynkin diagram of type G. Each node has SU( N i ) gauge group of general rank, Chern-Simons level κ i and additional w i fundamentals. When the total flavor number at each node is less than or equal to 2 N i - 2| κ i |, we give general rules under which the symmetries associated to instanton currents are enhanced to G × G or a subgroup of it in the UV 5d superconformal theory. When the total flavor number violates that condition at some of the nodes, further enhancement of flavor symmetries occurs. In particular we find a large class of gauge theories interpreted as S 1 compactification of 6d superconformal theories which are waiting for string/F-theory realization. We also consider hypermultiplets in (anti-)symmetric representation.

Towards a realistic model of Higgsless electroweak symmetry breaking.

PubMed

Csáki, Csaba; Grojean, Christophe; Pilo, Luigi; Terning, John

2004-03-12

We present a 5D gauge theory in warped space based on a bulk SU(2)L x SU(2)R x U(1)(B-L) gauge group where the gauge symmetry is broken by boundary conditions. The symmetry breaking pattern and the mass spectrum resemble that in the standard model (SM). To leading order in the warp factor the rho parameter and the coupling of the Z (S parameter) are as in the SM, while corrections are expected at the level of a percent. From the anti-de Sitter (AdS) conformal field theory point of view the model presented here can be viewed as the AdS dual of a (walking) technicolorlike theory, in the sense that it is the presence of the IR brane itself that breaks electroweak symmetry, and not a localized Higgs on the IR brane (which should be interpreted as a composite Higgs model). This model predicts the lightest W, Z, and gamma resonances to be at around 1.2 TeV, and no fundamental (or composite) Higgs particles.

4d $$ \\mathcal{N} $$=2 theories with disconnected gauge groups

DOE PAGES

Argyres, Philip C.; Martone, Mario

2017-03-28

In this paper we present a beautifully consistent web of evidence for the existence of interacting 4d rank-1more » $$ \\mathcal{N} $$ = 2 SCFTs obtained from gauging discrete subgroups of global symmetries of other existing 4d rank-1 $$ \\mathcal{N} $$ = 2 SCFTs. The global symmetries that can be gauged involve a non-trivial combination of discrete subgroups of the U(1) R, low-energy EM duality group SL(2,Z), and the outer automorphism group of the flavor symmetry algebra, Out(F ). The theories that we construct are remarkable in many ways: (i) two of them have exceptional F 4 and G 2 flavor groups; (ii) they substantially complete the picture of the landscape of rank-1 $$ \\mathcal{N} $$ = 2 SCFTs as they realize all but one of the remaining consistent rank-1 Seiberg-Witten geometries that we previously constructed but were not associated to known SCFTs; and (iii) some of them have enlarged $$ \\mathcal{N} $$ = 3 SUSY, and have not been previously constructed. They are also examples of SCFTs which violate the ShapereTachikawa relation between the conformal central charges and the scaling dimension of the Coulomb branch vev. Here, we propose a modification of the formulas computing these central charges from the topologically twisted Coulomb branch partition function which correctly compute them for discretely gauged theories.« less

Gauge invariance of fractionally charged quasiparticles and hidden topological Zn symmetry

NASA Astrophysics Data System (ADS)

Wu, Yong-Shi; Hatsugai, Yasuhiro; Kohmoto, Mahito

1991-02-01

Using the braid-group formalism we study the consequences of gauge invariance for fractionally charged anyonic quasiparticles in a two-dimensional multiply connected system. It is shown that gauge invariance requires multicomponent wave functions, and leads to the emergence of a hidden topological Zn symmetry with associated quantum number and unavoidable occurrence of level crossings for many-body eigenstates. In certain situations, it relates the fractional charge to anyon statistics. The implications for the fractional quantum Hall effect are also discussed.

Kaluza-Klein theories as a tool to find new gauge symmetries

NASA Astrophysics Data System (ADS)

Dolan, L.

Non-abelian Kaluza-Klein theories are studied with respect to using the invariances of multi-dimensional general relativity to investigate hidden symmetry, such as Kac-Mody Lie algebras, of the four-dimensional Yang-Mills theory. Several properties of the affine transformations on the self-dual set are identified and are used to motivate the Kaluza-Klein analysis. In this context, a system of differential equations is derived for new symmetry transformations which may be extendable to the full gauge theory.

The chiral magnetic effect and chiral symmetry breaking in SU(3) quenched lattice gauge theory

DOE Office of Scientific and Technical Information (OSTI.GOV)

Braguta, V. V., E-mail: braguta@mail.ru; Buividovich, P. V., E-mail: buividovich@itep.ru; Kalaydzhyan, T., E-mail: tigran.kalaydzhyan@desy.de

2012-04-15

We study some properties of the non-Abelian vacuum induced by strong external magnetic field. We perform calculations in the quenched SU(3) lattice gauge theory with tadpole-improved Luescher-Weisz action and chirally invariant lattice Dirac operator. The following results are obtained: The chiral symmetry breaking is enhanced by the magnetic field. The chiral condensate depends on the strength of the applied field as a power function with exponent {nu} = 1.6 {+-} 0.2. There is a paramagnetic polarization of the vacuum. The corresponding susceptibility and other magnetic properties are calculated and compared with the theoretical estimations. There are nonzero local fluctuations ofmore » the chirality and electromagnetic current, which grow with the magnetic field strength. These fluctuations can be a manifestation of the Chiral Magnetic Effect.« less

Noether’s second theorem and Ward identities for gauge symmetries

DOE PAGES

Avery, Steven G.; Schwab, Burkhard U. W.

2016-02-04

Recently, a number of new Ward identities for large gauge transformations and large diffeomorphisms have been discovered. Some of the identities are reinterpretations of previously known statements, while some appear to be genuinely new. We present and use Noether’s second theorem with the path integral as a powerful way of generating these kinds of Ward identities. We reintroduce Noether’s second theorem and discuss how to work with the physical remnant of gauge symmetry in gauge fixed systems. We illustrate our mechanism in Maxwell theory, Yang-Mills theory, p-form field theory, and Einstein-Hilbert gravity. We comment on multiple connections between Noether’s secondmore » theorem and known results in the recent literature. Finally, our approach suggests a novel point of view with important physical consequences.« less

S-duality in SU(3) Yang-Mills theory with non-abelian unbroken gauge group

NASA Astrophysics Data System (ADS)

Schroers, B. J.; Bais, F. A.

1998-12-01

It is observed that the magnetic charges of classical monopole solutions in Yang-Mills-Higgs theory with non-abelian unbroken gauge group H are in one-to-one correspondence with coherent states of a dual or magnetic group H˜. In the spirit of the Goddard-Nuyts-Olive conjecture this observation is interpreted as evidence for a hidden magnetic symmetry of Yang-Mills theory. SU(3) Yang-Mills-Higgs theory with unbroken gauge group U(2) is studied in detail. The action of the magnetic group on semi-classical states is given explicitly. Investigations of dyonic excitations show that electric and magnetic symmetry are never manifest at the same time: Non-abelian magnetic charge obstructs the realisation of electric symmetry and vice-versa. On the basis of this fact the charge sectors in the theory are classified and their fusion rules are discussed. Non-abelian electric-magnetic duality is formulated as a map between charge sectors. Coherent states obey particularly simple fusion rules, and in the set of coherent states S-duality can be formulated as an SL(2, Z) mapping between sectors which leaves the fusion rules invariant.

On discrete symmetries for a whole Abelian model

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chauca, J.; Doria, R.; Aprendanet, Petropolis, 25600

Considering the whole concept applied to gauge theory a nonlinear abelian model is derived. A next step is to understand on the model properties. At this work, it will be devoted to discrete symmetries. For this, we will work based in two fields reference systems. This whole gauge symmetry allows to be analyzed through different sets which are the constructor basis {l_brace}D{sub {mu}},X{sup i}{sub {mu}}{r_brace} and the physical basis {l_brace}G{sub {mu}I}{r_brace}. Taking as fields reference system the diagonalized spin-1 sector, P, C, T and PCT symmetries are analyzed. They show that under this systemic model there are conservation laws drivenmore » for the parts and for the whole. It develops the meaning of whole-parity, field-parity and so on. However it is the whole symmetry that rules. This means that usually forbidden particles as pseudovector photons can be introduced through such whole abelian system. As result, one notices that the fields whole {l_brace}G{sub {mu}I}{r_brace} manifest a quanta diversity. It involves particles with different spins, masses and discrete quantum numbers under a same gauge symmetry. It says that without violating PCT symmetry different possibilities on discrete symmetries can be accommodated.« less

Spontaneous Breaking of Scale Invariance in U(N) Chern-Simons Gauge Theories in Three Dimensions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bardeen, William A.

2015-09-24

I explore the existence of a massive phase in a conformally invariant U(N) Chern-Simons gauge theories in D = 3 with matter fields in the fundamental representation. These models have attracted recent attention as being dual, in the conformal phase, to theories of higher spin gravity on AdS 4. Using the 0t Hooft large N expansion, exact solutions are obtained for scalar current correlators in the massive phase where the conformal symmetry is spontaneously broken. A massless dilaton appears as a composite state, and its properties are discussed. Solutions exist for matters field that are either bosons or fermions.

Spontaneous Breaking of Scale Invariance in U(N) Chern-Simons Gauge Theories in Three Dimensions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bardeen, William

2014-10-24

I explore the existence of a massive phase in a conformally invariant U(N) Chern-Simons gauge theories in D = 3 with matter fields in the fundamental representation. These models have attracted recent attention as being dual, in the conformal phase, to theories of higher spin gravity on AdS 4. Using the 1t Hooft large N expansion, exact solutions are obtained for scalar current correlators in the massive phase where the conformal symmetry is spontaneously broken. A massless dilaton appears as a composite state, and its properties are discussed. Solutions exist for matters field that are either bosons or fermions.

F(R) cosmology via Noether symmetry and Λ-Chaplygin Gas like model

NASA Astrophysics Data System (ADS)

Fazlollahi, H. R.

2018-06-01

In this work, we consider f (R) alternative theories of gravity with an eye to Noether symmetry through the gauge theorem. For non-vacuum models, one finds Λ like gravity with energy density of Chaplygin Gas. We also obtain the effective equation of state parameter for corresponding cosmology and scale factor behavior with respect to cosmic time which show that the model provides viable EoS and scale factor with respect to observational data.

Patterns of symmetry breaking in chiral QCD

NASA Astrophysics Data System (ADS)

Bolognesi, Stefano; Konishi, Kenichi; Shifman, Mikhail

2018-05-01

We consider S U (N ) Yang-Mills theory with massless chiral fermions in a complex representation of the gauge group. The main emphasis is on the so-called hybrid ψ χ η model. The possible patterns of realization of the continuous chiral flavor symmetry are discussed. We argue that the chiral symmetry is broken in conjunction with a dynamical Higgsing of the gauge group (complete or partial) by bifermion condensates. As a result a color-flavor locked symmetry is preserved. The 't Hooft anomaly matching proceeds via saturation of triangles by massless composite fermions or, in a mixed mode, i.e. also by the "weakly" coupled fermions associated with dynamical Abelianization, supplemented by a number of Nambu-Goldstone mesons. Gauge-singlet condensates are of the multifermion type and, though it cannot be excluded, the chiral symmetry realization via such gauge invariant condensates is more contrived (requires a number of four-fermion condensates simultaneously and, even so, problems remain) and less plausible. We conclude that in the model at hand, chiral flavor symmetry implies dynamical Higgsing by bifermion condensates.

Asymptotic symmetries and electromagnetic memory

NASA Astrophysics Data System (ADS)

Pasterski, Sabrina

2017-09-01

Recent investigations into asymptotic symmetries of gauge theory and gravity have illuminated connections between gauge field zero-mode sectors, the corresponding soft factors, and their classically observable counterparts — so called "memories". Namely, low frequency emissions in momentum space correspond to long time integrations of the corre-sponding radiation in position space. Memory effect observables constructed in this manner are non-vanishing in typical scattering processes, which has implications for the asymptotic symmetry group. Here we complete this triad for the case of large U(1) gauge symmetries at null infinity. In particular, we show that the previously studied electromagnetic memory effect, whereby the passage of electromagnetic radiation produces a net velocity kick for test charges in a distant detector, is the position space observable corresponding to th Weinberg soft photon pole in momentum space scattering amplitudes.

The effect of symmetry on the U L3 NEXAFS of octahedral coordinated uranium(vi)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bagus, Paul S.; Nelin, Connie J.; Ilton, Eugene S.

2017-03-21

We describe a detailed theoretical analysis of how distortions from ideal cubic or Oh symmetry affect the shape, in particular the width, of the U L3-edge NEXAFS for U(VI) in octahedral coordination. The full-width-half-maximum (FWHM) of the L3-edge white line decreases with increasing distortion from Oh symmetry due to the mixing of symmetry broken t2g and eg components of the excited state U(6d) orbitals. The mixing is allowed because of spin-orbit splitting of the ligand field split 6d orbitals. Especially for higher distortions, it is possible to identify a mixing between one of the t2g and one of the egmore » components, allowed in the double group representation when the spin-orbit interaction is taken into account. This mixing strongly reduces the ligand field splitting, which, in turn, leads to a narrowing of the U L3 white line. However, the effect of this mixing is partially offset by an increase in the covalent anti-bonding character of the highest energy spin-orbit split eg orbital. At higher distortions, mixing overwhelms the increasing anti-bonding character of this orbital which leads to an accelerated decrease in the FWHM with increasing distortion. Additional evidence for the effect of mixing of t2g and eg components is that the FWHM of the white line narrows whether the two axial U-O bond distances shorten or lengthen. Our ab initio theory uses relativistic wavefunctions for cluster models of the structures; empirical or semi-empirical parameters were not used to adjust prediction to experiment. A major advantage is that it provides a transparent approach for determining how the character and extent of the covalent mixing of the relevant U and O orbitals affect the U L3-edge white line.« less

Fermion-number violation in regularizations that preserve fermion-number symmetry

NASA Astrophysics Data System (ADS)

Golterman, Maarten; Shamir, Yigal

2003-01-01

There exist both continuum and lattice regularizations of gauge theories with fermions which preserve chiral U(1) invariance (“fermion number”). Such regularizations necessarily break gauge invariance but, in a covariant gauge, one recovers gauge invariance to all orders in perturbation theory by including suitable counterterms. At the nonperturbative level, an apparent conflict then arises between the chiral U(1) symmetry of the regularized theory and the existence of ’t Hooft vertices in the renormalized theory. The only possible resolution of the paradox is that the chiral U(1) symmetry is broken spontaneously in the enlarged Hilbert space of the covariantly gauge-fixed theory. The corresponding Goldstone pole is unphysical. The theory must therefore be defined by introducing a small fermion-mass term that breaks explicitly the chiral U(1) invariance and is sent to zero after the infinite-volume limit has been taken. Using this careful definition (and a lattice regularization) for the calculation of correlation functions in the one-instanton sector, we show that the ’t Hooft vertices are recovered as expected.

Continuous-spin mixed-symmetry fields in AdS(5)

NASA Astrophysics Data System (ADS)

Metsaev, R. R.

2018-05-01

Free mixed-symmetry continuous-spin fields propagating in AdS(5) space and flat R(4,1) space are studied. In the framework of a light-cone gauge formulation of relativistic dynamics, we build simple actions for such fields. The realization of relativistic symmetries on the space of light-cone gauge mixed-symmetry continuous-spin fields is also found. Interrelations between constant parameters entering the light-cone gauge actions and eigenvalues of the Casimir operators of space-time symmetry algebras are obtained. Using these interrelations and requiring that the field dynamics in AdS(5) be irreducible and classically unitary, we derive restrictions on the constant parameters and eigenvalues of the second-order Casimir operator of the algebra.

Weakly Isolated horizons: first order actions and gauge symmetries

NASA Astrophysics Data System (ADS)

Corichi, Alejandro; Reyes, Juan D.; Vukašinac, Tatjana

2017-04-01

The notion of Isolated Horizons has played an important role in gravitational physics, being useful from the characterization of the endpoint of black hole mergers to (quantum) black hole entropy. With an eye towards a canonical formulation we consider general relativity in terms of connection and vierbein variables and their corresponding first order actions. We focus on two main issues: (i) The role of the internal gauge freedom that exists, in the consistent formulations of the action principle, and (ii) the role that a 3  +  1 canonical decomposition has in the allowed internal gauge freedom. More concretely, we clarify in detail how the requirement of having well posed variational principles compatible with general weakly isolated horizons (WIHs) as internal boundaries does lead to a partial gauge fixing in the first order descriptions used previously in the literature. We consider the standard Hilbert-Palatini action together with the Holst extension (needed for a consistent 3  +  1 decomposition), with and without boundary terms at the horizon. We show in detail that, for the complete configuration space—with no gauge fixing—, while the Palatini action is differentiable without additional surface terms at the inner WIH boundary, the more general Holst action is not. The introduction of a surface term at the horizon—that renders the action for asymptotically flat configurations differentiable—does make the Holst action differentiable, but only if one restricts the configuration space and partially reduces the internal Lorentz gauge. For the second issue at hand, we show that upon performing a 3  +  1 decomposition and imposing the time gauge, there is a further gauge reduction of the Hamiltonian theory in terms of Ashtekar-Barbero variables to a U(1)-gauge theory on the horizon. We also extend our analysis to the more restricted boundary conditions of (strongly) isolated horizons as inner boundary. We show that even when the

Gauge symmetry and constraints structure for topologically massive AdS gravity: a symplectic viewpoint

NASA Astrophysics Data System (ADS)

Rodríguez-Tzompantzi, Omar; Escalante, Alberto

2018-05-01

By applying the Faddeev-Jackiw symplectic approach we systematically show that both the local gauge symmetry and the constraint structure of topologically massive gravity with a cosmological constant Λ , elegantly encoded in the zero-modes of the symplectic matrix, can be identified. Thereafter, via a suitable partial gauge-fixing procedure, the time gauge, we calculate the quantization bracket structure (generalized Faddeev-Jackiw brackets) for the dynamic variables and confirm that the number of physical degrees of freedom is one. This approach provides an alternative to explore the dynamical content of massive gravity models.

Entanglement entropy in (3 + 1)-d free U(1) gauge theory

NASA Astrophysics Data System (ADS)

Soni, Ronak M.; Trivedi, Sandip P.

2017-02-01

We consider the entanglement entropy for a free U(1) theory in 3+1 dimensions in the extended Hilbert space definition. By taking the continuum limit carefully we obtain a replica trick path integral which calculates this entanglement entropy. The path integral is gauge invariant, with a gauge fixing delta function accompanied by a Faddeev -Popov determinant. For a spherical region it follows that the result for the logarithmic term in the entanglement, which is universal, is given by the a anomaly coefficient. We also consider the extractable part of the entanglement, which corresponds to the number of Bell pairs which can be obtained from entanglement distillation or dilution. For a spherical region we show that the coefficient of the logarithmic term for the extractable part is different from the extended Hilbert space result. We argue that the two results will differ in general, and this difference is accounted for by a massless scalar living on the boundary of the region of interest.

The calculation of the contributions to low energy e+H2 scattering from sigma u+ and Pion u symmetries using the Kohn variational method

NASA Technical Reports Server (NTRS)

Armour, E. A. G.; Baker, D. J.; Plummer, M.

1990-01-01

Above incident energies of about 2 eV, the contribution to the total cross section in positron+H2 scattering from the sigma g+ symmetry is insufficient to account for the experimental value. Calculations carried out of the lowest partial waves of sigma u+ symmetry and Pion u symmetry using the Kohn variational method are described. The contributions to the total cross section from the two equivalent partial waves of Pion u symmetry significantly reduce the discrepancy with experiment up to incident energies of 4 to 5 eV. Comparisons are made with recent R-matrix calculations performed by Danby and Tennyson.

On the tensionless limit of gauged WZW models

NASA Astrophysics Data System (ADS)

Bakas, I.; Sourdis, C.

2004-06-01

The tensionless limit of gauged WZW models arises when the level of the underlying Kac-Moody algebra assumes its critical value, equal to the dual Coxeter number, in which case the central charge of the Virasoro algebra becomes infinite. We examine this limit from the world-sheet and target space viewpoint and show that gravity decouples naturally from the spectrum. Using the two-dimensional black-hole coset SL(2,Bbb R)k/U(1) as illustrative example, we find for k = 2 that the world-sheet symmetry is described by a truncated version of Winfty generated by chiral fields with integer spin s geq 3, whereas the Virasoro algebra becomes abelian and it can be consistently factored out. The geometry of target space looks like an infinitely curved hyperboloid, which invalidates the effective field theory description and conformal invariance can no longer be used to yield reliable space-time interpretation. We also compare our results with the null gauging of WZW models, which correspond to infinite boost in target space and they describe the Liouville mode that decouples in the tensionless limit. A formal BRST analysis of the world-sheet symmetry suggests that the central charge of all higher spin generators should be fixed to a critical value, which is not seen by the contracted Virasoro symmetry. Generalizations to higher dimensional coset models are also briefly discussed in the tensionless limit, where similar observations are made.

Atomic quantum simulation of the lattice gauge-Higgs model: Higgs couplings and emergence of exact local gauge symmetry.

PubMed

Kasamatsu, Kenichi; Ichinose, Ikuo; Matsui, Tetsuo

2013-09-13

Recently, the possibility of quantum simulation of dynamical gauge fields was pointed out by using a system of cold atoms trapped on each link in an optical lattice. However, to implement exact local gauge invariance, fine-tuning the interaction parameters among atoms is necessary. In the present Letter, we study the effect of violation of the U(1) local gauge invariance by relaxing the fine-tuning of the parameters and showing that a wide variety of cold atoms is still a faithful quantum simulator for a U(1) gauge-Higgs model containing a Higgs field sitting on sites. The clarification of the dynamics of this gauge-Higgs model sheds some light upon various unsolved problems, including the inflation process of the early Universe. We study the phase structure of this model by Monte Carlo simulation and also discuss the atomic characteristics of the Higgs phase in each simulator.

Flavor physics without flavor symmetries

NASA Astrophysics Data System (ADS)

Buchmuller, Wilfried; Patel, Ketan M.

2018-04-01

We quantitatively analyze a quark-lepton flavor model derived from a six-dimensional supersymmetric theory with S O (10 )×U (1 ) gauge symmetry, compactified on an orbifold with magnetic flux. Two bulk 16 -plets charged under the U (1 ) provide the three quark-lepton generations whereas two uncharged 10 -plets yield two Higgs doublets. At the orbifold fixed points mass matrices are generated with rank one or two. Moreover, the zero modes mix with heavy vectorlike split multiplets. The model possesses no flavor symmetries. Nevertheless, there exist a number of relations between Yukawa couplings, remnants of the underlying grand unified theory symmetry and the wave function profiles of the zero modes, which lead to a prediction of the light neutrino mass scale, mν 1˜10-3 eV and heavy Majorana neutrino masses in the range from 1 012 to 1 014 GeV . The model successfully includes thermal leptogenesis.

Individual eigenvalue distributions of crossover chiral random matrices and low-energy constants of SU(2) × U(1) lattice gauge theory

NASA Astrophysics Data System (ADS)

Yamamoto, Takuya; Nishigaki, Shinsuke M.

2018-02-01

We compute individual distributions of low-lying eigenvalues of a chiral random matrix ensemble interpolating symplectic and unitary symmetry classes by the Nyström-type method of evaluating the Fredholm Pfaffian and resolvents of the quaternion kernel. The one-parameter family of these distributions is shown to fit excellently the Dirac spectra of SU(2) lattice gauge theory with a constant U(1) background or dynamically fluctuating U(1) gauge field, which weakly breaks the pseudoreality of the unperturbed SU(2) Dirac operator. The observed linear dependence of the crossover parameter with the strength of the U(1) perturbations leads to precise determination of the pseudo-scalar decay constant, as well as the chiral condensate in the effective chiral Lagrangian of the AI class.

Alternative [SU(3)]4 model of leptonic color and dark matter

NASA Astrophysics Data System (ADS)

Kownacki, Corey; Ma, Ernest; Pollard, Nicholas; Popov, Oleg; Zakeri, Mohammadreza

2018-03-01

The alternative [ SU (3) ] 4 model of leptonic color and dark matter is discussed. It unifies at MU ∼1014 GeV and has the low-energy subgroup SU(3)q × SU(2)l × SU(2)L × SU(2)R × U(1)X with (u , h) R instead of (u , d) R as doublets under SU(2)R. It has the built-in global U (1) dark symmetry which is generalized B- L. In analogy to SU(3)q quark triplets, it has SU(2)l hemion doublets which have half-integral charges and are confined by SU(2)l gauge bosons (stickons). In analogy to quarkonia, their vector bound states (hemionia) are uniquely suited for exploration at a future e-e+ collider.

Scalar dark matter interpretation of the DAMPE data with U(1) gauge interactions

NASA Astrophysics Data System (ADS)

Cao, Junjie; Feng, Lei; Guo, Xiaofei; Shang, Liangliang; Wang, Fei; Wu, Peiwen

2018-05-01

Recently, the Dark Matter Particle Explorer (DAMPE) experiment released the new measurement of the total cosmic e+e- flux between 25 GeV and 4.6 TeV, which indicates a spectral softening at around 0.9 TeV and a tentative peak at around 1.4 TeV. We utilize a scalar dark matter (DM) model to explain the DAMPE peak by χ χ →Z'Z'→ℓℓ ¯ ℓ'ℓ' ¯ with an additional anomaly-free gauged U (1 ) family symmetry, in which χ , Z', and ℓ(') denote, respectively, the scalar DM, the new gauge boson, and ℓ(')=e , μ , τ with mχ˜mZ'˜2 ×1.5 (TeV ) . We first illustrate that the minimal framework GSM×U (1 )Y' with the above mass choices can explain the DAMPE excess, which, however, be excluded by LHC constraints from the Z' searches. Then, we study a nonminimal framework GSM×U (1 )Y'×U (1 )Y'' in which U (1 )Y'' mixes with U (1)Y'. We show that such a framework can interpret the DAMPE data and at the same time survive all other constraints including the DM relic abundance, DM direct detection, and collider bounds. We also investigate the predicted e+e- spectrum in this framework and find that the mass splitting Δ m =mχ-mZ'' should be less than about 17 GeV to produce the peaklike structure.

Exploring a new S U (4 ) symmetry of meson interpolators

NASA Astrophysics Data System (ADS)

Glozman, L. Ya.; Pak, M.

2015-07-01

In recent lattice calculations it has been discovered that mesons upon truncation of the quasizero modes of the Dirac operator obey a symmetry larger than the S U (2 )L×S U (2 )R×U (1 )A symmetry of the QCD Lagrangian. This symmetry has been suggested to be S U (4 )⊃S U (2 )L×S U (2 )R×U (1 )A that mixes not only the u- and d-quarks of a given chirality, but also the left- and right-handed components. Here it is demonstrated that bilinear q ¯q interpolating fields of a given spin J ≥1 transform into each other according to irreducible representations of S U (4 ) or, in general, S U (2 NF). This fact together with the coincidence of the correlation functions establishes S U (4 ) as a symmetry of the J ≥1 mesons upon quasizero mode reduction. It is shown that this symmetry is a symmetry of the confining instantaneous charge-charge interaction in QCD. Different subgroups of S U (4 ) as well as the S U (4 ) algebra are explored.

Implications of hidden gauged U (1 ) model for B anomalies

NASA Astrophysics Data System (ADS)

Fuyuto, Kaori; Li, Hao-Lin; Yu, Jiang-Hao

2018-06-01

We propose a hidden gauged U (1 )H Z' model to explain deviations from the standard model (SM) values in lepton flavor universality known as RK and RD anomalies. The Z' only interacts with the SM fermions via their mixing with vectorlike doublet fermions after the U (1 )H symmetry breaking, which leads to b →s μ μ transition through the Z' at tree level. Moreover, introducing an additional mediator, inert-Higgs doublet, yields b →c τ ν process via charged scalar contribution at tree level. Using flavio package, we scrutinize adequate sizes of the relevant Wilson coefficients to these two processes by taking various flavor observables into account. It is found that significant mixing between the vectorlike and the second generation leptons is needed for the RK anomaly. A possible explanation of the RD anomaly can also be simultaneously addressed in a motivated situation, where a single scalar operator plays a dominant role, by the successful model parameters for the RK anomaly.

Supersymmetric solutions of the cosmological, gauged, ℂ magic model

NASA Astrophysics Data System (ADS)

Chimento, Samuele; Ortín, Tomás; Ruipérez, Alejandro

2018-05-01

We construct supersymmetric solutions of theories of gauged N = 1 , d = 5 supergravity coupled to vector multiplets with a U(1)R Abelian (Fayet-Iliopoulos) gauging and an independent SU(2) gauging associated to an SU(2) isometry group of the Real Special scalar manifold. These theories provide minimal supersymmetrizations of 5-dimensional SU(2) Einstein-Yang-Mills theories with negative cosmological constant. We consider a minimal model with these gauge groups and the "magic model" based on the Jordan algebra J 3 ℂ with gauge group SU(3) × U(1)R, which is a consistent truncation of maximal SO(6)-gauged supergravity in d = 5 and whose solutions can be embedded in Type IIB Superstring Theory. We find several solutions containing selfdual SU(2) instantons, some of which asymptote to AdS5 and some of which are very small, supersymmetric, deformations of AdS5. We also show how some of those solutions can be embedded in Romans' SU(2) × U(1)-gauged half-maximal supergravity, which was obtained by Lu, Pope and Tran by compactification of the Type IIB Superstring effective action. This provides another way of uplifting those solutions to 10 dimensions.

Gauge transformation and symmetries of the commutative multicomponent BKP hierarchy

NASA Astrophysics Data System (ADS)

Li, Chuanzhong

2016-01-01

In this paper, we defined a new multi-component B type Kadomtsev-Petviashvili (BKP) hierarchy that takes values in a commutative subalgebra of {gl}(N,{{C}}). After this, we give the gauge transformation of this commutative multicomponent BKP (CMBKP) hierarchy. Meanwhile, we construct a new constrained CMBKP hierarchy that contains some new integrable systems, including coupled KdV equations under a certain reduction. After this, the quantum torus symmetry and quantum torus constraint on the tau function of the commutative multi-component BKP hierarchy will be constructed.

String Scale Gauge Coupling Unification with Vector-Like Exotics and Noncanonical U(1)Y Normalization

NASA Astrophysics Data System (ADS)

Barger, V.; Jiang, Jing; Langacker, Paul; Li, Tianjun

We use a new approach to study string scale gauge coupling unification systematically, allowing both the possibility of noncanonical U(1)Y normalization and the existence of vector-like particles whose quantum numbers are the same as those of the Standard Model (SM) fermions and their Hermitian conjugates and the SM adjoint particles. We first give all the independent sets (Yi) of particles that can be employed to achieve SU(3)C and SU(2)L string scale gauge coupling unification and calculate their masses. Second, for a noncanonical U(1)Y normalization, we obtain string scale SU(3)C ×SU(2)L ×U(1)Y gauge coupling unification by choosing suitable U(1)Y normalizations for each of the Yi sets. Alternatively, for the canonical U(1)Y normalization, we achieve string scale gauge coupling unification by considering suitable combinations of the Yi sets or by introducing additional independent sets (Zi), that do not affect the SU(3)C ×SU(2)L unification at tree level, and then choosing suitable combinations, one from the Yi sets and one from the Zi sets. We also briefly discuss string scale gauge coupling unification in models with higher Kac-Moody levels for SU(2)L or SU(3)C.

Strong Coupling Gauge Theories in LHC ERA

NASA Astrophysics Data System (ADS)

Fukaya, H.; Harada, M.; Tanabashi, M.; Yamawaki, K.

2011-01-01

AdS/QCD, light-front holography, and the nonperturbative running coupling / Stanley J. Brodsky, Guy de Teramond and Alexandre Deur -- New results on non-abelian vortices - Further insights into monopole, vortex and confinement / K. Konishi -- Study on exotic hadrons at B-factories / Toru Iijima -- Cold compressed baryonic matter with hidden local symmetry and holography / Mannque Rho -- Aspects of baryons in holographic QCD / T. Sakai -- Nuclear force from string theory / K. Hashimoto -- Integrating out holographic QCD back to hidden local symmetry / Masayasu Harada, Shinya Matsuzaki and Koichi Yamawaki -- Holographic heavy quarks and the giant Polyakov loop / Gianluca Grignani, Joanna Karczmarek and Gordon W. Semenoff -- Effect of vector-axial-vector mixing to dilepton spectrum in hot and/or dense matter / Masayasu Harada and Chihiro Sasaki -- Infrared behavior of ghost and gluon propagators compatible with color confinement in Yang-Mills theory with the Gribov horizon / Kei-Ichi Kondo -- Chiral symmetry breaking on the lattice / Hidenori Fukaya [for JLQCD and TWQCD collaborations] -- Gauge-Higgs unification: Stable Higgs bosons as cold dark matter / Yutaka Hosotani -- The limits of custodial symmetry / R. Sekhar Chivukula ... [et al.] -- Higgs searches at the tevatron / Kazuhiro Yamamoto [for the CDF and D[symbol] collaborations] -- The top triangle moose / R. S. Chivukula ... [et al.] -- Conformal phase transition in QCD like theories and beyond / V. A. Miransky -- Gauge-Higgs unification at LHC / Nobuhito Maru and Nobuchika Okada -- W[symbol]W[symbol] scattering in Higgsless models: Identifying better effective theories / Alexander S. Belyaev ... [et al.] -- Holographic estimate of Muon g - 2 / Deog Ki Hong -- Gauge-Higgs dark matter / T. Yamashita -- Topological and curvature effects in a multi-fermion interaction model / T. Inagaki and M. Hayashi -- A model of soft mass generation / J. Hosek -- TeV physics and conformality / Thomas Appelquist -- Conformal

Global U(1 ) Y⊗BRST symmetry and the LSS theorem: Ward-Takahashi identities governing Green's functions, on-shell T -matrix elements, and the effective potential in the scalar sector of the spontaneously broken extended Abelian Higgs model

NASA Astrophysics Data System (ADS)

Lynn, Bryan W.; Starkman, Glenn D.

2017-09-01

The weak-scale U (1 )Y Abelian Higgs model (AHM) is the simplest spontaneous symmetry breaking (SSB) gauge theory: a scalar ϕ =1/√{2 }(H +i π )≡1/√{2 }H ˜ei π ˜/⟨H ⟩ and a vector Aμ. The extended AHM (E-AHM) adds certain heavy (MΦ2,Mψ2˜MHeavy2≫⟨H ⟩2˜mWeak2 ) spin S =0 scalars Φ and S =1/2 fermions ψ . In Lorenz gauge, ∂μAμ=0 , the SSB AHM (and E-AHM) has a global U (1 )Y conserved physical current, but no conserved charge. As shown by T. W. B. Kibble, the Goldstone theorem applies, so π ˜ is a massless derivatively coupled Nambu-Goldstone boson (NGB). Proof of all-loop-orders renormalizability and unitarity for the SSB case is tricky because the Becchi-Rouet-Stora-Tyutin (BRST)-invariant Lagrangian is not U (1 )Y symmetric. Nevertheless, Slavnov-Taylor identities guarantee that on-shell T-matrix elements of physical states Aμ,ϕ , Φ , ψ (but not ghosts ω , η ¯ ) are independent of anomaly-free local U (1 )Y gauge transformations. We observe here that they are therefore also independent of the usual anomaly-free U (1 )Y global/rigid transformations. It follows that the associated global current, which is classically conserved only up to gauge-fixing terms, is exactly conserved for amplitudes of physical states in the AHM and E-AHM. We identify corresponding "undeformed" [i.e. with full global U (1 )Y symmetry] Ward-Takahashi identities (WTI). The proof of renormalizability and unitarity, which relies on BRST invariance, is undisturbed. In Lorenz gauge, two towers of "1-soft-pion" SSB global WTI govern the ϕ -sector, and represent a new global U (1 )Y⊗BRST symmetry not of the Lagrangian but of the physics. The first gives relations among off-shell Green's functions, yielding powerful constraints on the all-loop-orders ϕ -sector SSB E-AHM low-energy effective Lagrangian and an additional global shift symmetry for the NGB: π ˜→π ˜+⟨H ⟩θ . A second tower, governing on-shell T-matrix elements, replaces the old Adler

Common origin of 3.55 keV x-ray line and gauge coupling unification with left-right dark matter

NASA Astrophysics Data System (ADS)

Borah, Debasish; Dasgupta, Arnab; Patra, Sudhanwa

2017-12-01

We present a minimal left-right dark matter framework that can simultaneously explain the recently observed 3.55 keV x-ray line from several galaxy clusters and gauge coupling unification at high energy scale. Adopting a minimal dark matter strategy, we consider both left and right handed triplet fermionic dark matter candidates which are stable by virtue of a remnant Z2≃(-1 )B -L symmetry arising after the spontaneous symmetry breaking of left-right gauge symmetry to that of the standard model. A scalar bitriplet field is incorporated whose first role is to allow radiative decay of right handed triplet dark matter into the left handed one and a photon with energy 3.55 keV. The other role this bitriplet field at TeV scale plays is to assist in achieving gauge coupling unification at a high energy scale within a nonsupersymmetric S O (10 ) model while keeping the scale of left-right gauge symmetry around the TeV corner. Apart from solving the neutrino mass problem and giving verifiable new contributions to neutrinoless double beta decay and charged lepton flavor violation, the model with TeV scale gauge bosons can also give rise to interesting collider signatures like diboson excess, dilepton plus two jets excess reported recently in the large hadron collider data.

T-branes through 3d mirror symmetry

NASA Astrophysics Data System (ADS)

Collinucci, Andrés; Giacomelli, Simone; Savelli, Raffaele; Valandro, Roberto

2016-07-01

T-branes are exotic bound states of D-branes, characterized by mutually non-commuting vacuum expectation values for the worldvolume scalars. The M/F-theory geometry lifting D6/D7-brane configurations is blind to the T-brane data. In this paper, we make this data manifest, by probing the geometry with an M2-brane. We find that the effect of a T-brane is to deform the membrane worldvolume superpotential with monopole operators, which partially break the three-dimensional flavor symmetry, and reduce super-symmetry from {N} = 4 to {N} = 2. Our main tool is 3d mirror symmetry. Through this language, a very concrete framework is developed for understanding T-branes in M-theory. This leads us to uncover a new class of {N} = 2 quiver gauge theories, whose Higgs branches mimic those of membranes at ADE singularities, but whose Coulomb branches differ from their {N} = 4 counterparts.

[SU(2)]3 dark matter

NASA Astrophysics Data System (ADS)

Ma, Ernest

2018-05-01

An extra SU(2)D gauge factor is added to the well-known left-right extension of the standard model (SM) of quarks and leptons. Under SU(2)L × SU(2)R × SU(2)D, two fermion bidoublets (2 , 1 , 2) and (1 , 2 , 2) are assumed. The resulting model has an automatic dark U (1) symmetry, in the same way that the SM has automatic baryon and lepton U (1) symmetries. Phenomenological implications are discussed, as well as the possible theoretical origins of this proposal.

Exact partition functions for gauge theories on Rλ3

NASA Astrophysics Data System (ADS)

Wallet, Jean-Christophe

2016-11-01

The noncommutative space Rλ3, a deformation of R3, supports a 3-parameter family of gauge theory models with gauge-invariant harmonic term, stable vacuum and which are perturbatively finite to all orders. Properties of this family are discussed. The partition function factorizes as an infinite product of reduced partition functions, each one corresponding to the reduced gauge theory on one of the fuzzy spheres entering the decomposition of Rλ3. For a particular sub-family of gauge theories, each reduced partition function is exactly expressible as a ratio of determinants. A relation with integrable 2-D Toda lattice hierarchy is indicated.

Nilpotent symmetries and Curci-Ferrari-type restrictions in 2D non-Abelian gauge theory: Superfield approach

NASA Astrophysics Data System (ADS)

Srinivas, N.; Malik, R. P.

2017-11-01

We derive the off-shell nilpotent symmetries of the two (1 + 1)-dimensional (2D) non-Abelian 1-form gauge theory by using the theoretical techniques of the geometrical superfield approach to Becchi-Rouet-Stora-Tyutin (BRST) formalism. For this purpose, we exploit the augmented version of superfield approach (AVSA) and derive theoretically useful nilpotent (anti-)BRST, (anti-)co-BRST symmetries and Curci-Ferrari (CF)-type restrictions for the self-interacting 2D non-Abelian 1-form gauge theory (where there is no interaction with matter fields). The derivation of the (anti-)co-BRST symmetries and all possible CF-type restrictions are completely novel results within the framework of AVSA to BRST formalism where the ordinary 2D non-Abelian theory is generalized onto an appropriately chosen (2, 2)-dimensional supermanifold. The latter is parametrized by the superspace coordinates ZM = (xμ,𝜃,𝜃¯) where xμ (with μ = 0, 1) are the bosonic coordinates and a pair of Grassmannian variables (𝜃,𝜃¯) obey the relationships: 𝜃2 = 𝜃¯2 = 0, 𝜃𝜃¯ + 𝜃¯𝜃 = 0. The topological nature of our 2D theory allows the existence of a tower of CF-type restrictions.

A Strain Gauge Manual.

DTIC Science & Technology

1984-04-01

Applied Science Publications Ltd. (U.K.) "Strain Gauges, Kinds and Uses", H.K.P. Neubert . McMillan, London (U.K.) "A Strain Gauge Primer", Perry and...G.R. Paul (Materials) A.A. Baker (Materials) I.G. Powlesland G. Wright ." P. Ferrerotto J. Madej B. Ashcroft E.S. Moody M.T. Adams M. Cameron (GAF) (2

Electric-magnetic dualities in non-abelian and non-commutative gauge theories

NASA Astrophysics Data System (ADS)

Ho, Jun-Kai; Ma, Chen-Te

2016-08-01

Electric-magnetic dualities are equivalence between strong and weak coupling constants. A standard example is the exchange of electric and magnetic fields in an abelian gauge theory. We show three methods to perform electric-magnetic dualities in the case of the non-commutative U (1) gauge theory. The first method is to use covariant field strengths to be the electric and magnetic fields. We find an invariant form of an equation of motion after performing the electric-magnetic duality. The second method is to use the Seiberg-Witten map to rewrite the non-commutative U (1) gauge theory in terms of abelian field strength. The third method is to use the large Neveu Schwarz-Neveu Schwarz (NS-NS) background limit (non-commutativity parameter only has one degree of freedom) to consider the non-commutative U (1) gauge theory or D3-brane. In this limit, we introduce or dualize a new one-form gauge potential to get a D3-brane in a large Ramond-Ramond (R-R) background via field redefinition. We also use perturbation to study the equivalence between two D3-brane theories. Comparison of these methods in the non-commutative U (1) gauge theory gives different physical implications. The comparison reflects the differences between the non-abelian and non-commutative gauge theories in the electric-magnetic dualities. For a complete study, we also extend our studies to the simplest abelian and non-abelian p-form gauge theories, and a non-commutative theory with the non-abelian structure.

New chiral fermions, a new gauge interaction, Dirac neutrinos, and dark matter

DOE PAGES

de Gouvea, Andre; Hernandez, Daniel

2015-10-07

Here, we propose that all light fermionic degrees of freedom, including the Standard Model (SM) fermions and all possible light beyond-the-standard-model fields, are chiral with respect to some spontaneously broken abelian gauge symmetry. Hypercharge, for example, plays this role for the SM fermions. We introduce a new symmetry, U(1) ν , for all new light fermionic states. Anomaly cancellations mandate the existence of several new fermion fields with nontrivial U(1) ν charges. We develop a concrete model of this type, for which we show that (i) some fermions remain massless after U(1) ν breaking — similar to SM neutrinos —more » and (ii) accidental global symmetries translate into stable massive particles — similar to SM protons. These ingredients provide a solution to the dark matter and neutrino mass puzzles assuming one also postulates the existence of heavy degrees of freedom that act as “mediators” between the two sectors. The neutrino mass mechanism described here leads to parametrically small Dirac neutrino masses, and the model also requires the existence of at least four Dirac sterile neutrinos. Finally, we describe a general technique to write down chiral-fermions-only models that are at least anomaly-free under a U(1) gauge symmetry.« less

New chiral fermions, a new gauge interaction, Dirac neutrinos, and dark matter

DOE Office of Scientific and Technical Information (OSTI.GOV)

de Gouvea, Andre; Hernandez, Daniel

Here, we propose that all light fermionic degrees of freedom, including the Standard Model (SM) fermions and all possible light beyond-the-standard-model fields, are chiral with respect to some spontaneously broken abelian gauge symmetry. Hypercharge, for example, plays this role for the SM fermions. We introduce a new symmetry, U(1) ν , for all new light fermionic states. Anomaly cancellations mandate the existence of several new fermion fields with nontrivial U(1) ν charges. We develop a concrete model of this type, for which we show that (i) some fermions remain massless after U(1) ν breaking — similar to SM neutrinos —more » and (ii) accidental global symmetries translate into stable massive particles — similar to SM protons. These ingredients provide a solution to the dark matter and neutrino mass puzzles assuming one also postulates the existence of heavy degrees of freedom that act as “mediators” between the two sectors. The neutrino mass mechanism described here leads to parametrically small Dirac neutrino masses, and the model also requires the existence of at least four Dirac sterile neutrinos. Finally, we describe a general technique to write down chiral-fermions-only models that are at least anomaly-free under a U(1) gauge symmetry.« less

Emergence of a new S U (4 ) symmetry in the baryon spectrum

NASA Astrophysics Data System (ADS)

Denissenya, M.; Glozman, L. Ya.; Pak, M.

2015-10-01

Recently, a large degeneracy of J =1 mesons—that is, larger than the S U (2 )L×S U (2 )R×U (1 )A symmetry of the QCD Lagrangian—has been discovered upon truncation of the near-zero modes from the valence quark propagators. It has been found that this degeneracy represents the S U (4 ) group that includes the chiral rotations as well as the mixing of left- and right-handed quarks. This symmetry group turns out to be a symmetry of confinement in QCD. Consequently, one expects that the same symmetry should persist upon the near-zero mode removal in other hadron sectors as well. It has been shown that indeed the J =2 mesons follow the same symmetry pattern upon the low-lying mode elimination. Here we demonstrate the S U (4 ) symmetry of baryons once the near-zero modes are removed from the quark propagators. We also show a degeneracy of states belonging to different irreducible representations of S U (4 ). This implies a larger symmetry that includes S U (4 ) as a subgroup.

Unification of gauge, family, and flavor symmetries illustrated in gauged SU(12) models

DOE PAGES

Albright, Carl H.; Feger, Robert P.; Kephart, Thomas W.

2016-04-25

In this study, to explain quark and lepton masses and mixing angles, one has to extend the standard model, and the usual practice is to put the quarks and leptons into irreducible representations of discrete groups. We argue that discrete flavor symmetries (and their concomitant problems) can be avoided if we extend the gauge group. In the framework of SU(12) we give explicit examples of models having varying degrees of predictability obtained by scanning over groups and representations and identifying cases with operators contributing to mass and mixing matrices that need little fine- tuning of prefactors. Fitting with quark andmore » lepton masses run to the GUT scale and known mixing angles allows us to make predictions for the neutrino masses and hierarchy, the octant of the atmospheric mixing angle, leptonic CP violation, Majorana phases, and the effective mass observed in neutrinoless double beta decay.« less

Sneutrino dark matter: Symmetry protection and cosmic ray anomalies

DOE Office of Scientific and Technical Information (OSTI.GOV)

Demir, Durmus A.; Everett, Lisa L.; Frank, Mariana

2010-02-01

We present an R-parity conserving model of sneutrino dark matter within a Higgsphilic U(1){sup '} extension of the minimal supersymmetric standard model. In this theory, the {mu} parameter and light Dirac neutrino masses are generated naturally upon the breaking of the U(1){sup '} gauge symmetry. One of the right-handed sneutrinos is the lightest supersymmetric particle. The leptonic and hadronic decays of another sneutrino, taken to be the next-to-lightest superpartner, allow for a natural fit to the recent results reported by the PAMELA experiment. We perform a detailed calculation of the dark matter relic density in this scenario, and show thatmore » the model is consistent with the ATIC and Fermi LAT experiments.« less

Reformulation of the symmetries of first-order general relativity

NASA Astrophysics Data System (ADS)

Montesinos, Merced; González, Diego; Celada, Mariano; Díaz, Bogar

2017-10-01

We report a new internal gauge symmetry of the n-dimensional Palatini action with cosmological term (n>3 ) that is the generalization of three-dimensional local translations. This symmetry is obtained through the direct application of the converse of Noether’s second theorem on the theory under consideration. We show that diffeomorphisms can be expressed as linear combinations of it and local Lorentz transformations with field-dependent parameters up to terms involving the variational derivatives of the action. As a result, the new internal symmetry together with local Lorentz transformations can be adopted as the fundamental gauge symmetries of general relativity. Although their gauge algebra is open in general, it allows us to recover, without resorting to the equations of motion, the very well-known Lie algebra satisfied by translations and Lorentz transformations in three dimensions. We also report the analog of the new gauge symmetry for the Holst action with cosmological term, finding that it explicitly depends on the Immirzi parameter. The same result concerning its relation to diffeomorphisms and the open character of the gauge algebra also hold in this case. Finally, we consider the non-minimal coupling of a scalar field to gravity in n dimensions and establish that the new gauge symmetry is affected by this matter field. Our results indicate that general relativity in dimension greater than three can be thought of as a gauge theory.

R symmetries and a heterotic MSSM

NASA Astrophysics Data System (ADS)

Kappl, Rolf; Nilles, Hans Peter; Schmitz, Matthias

2015-02-01

We employ powerful techniques based on Hilbert and Gröbner bases to analyze particle physics models derived from string theory. Individual models are shown to have a huge landscape of vacua that differ in their phenomenological properties. We explore the (discrete) symmetries of these vacua, the new R symmetry selection rules and their consequences for moduli stabilization.

New symmetries and ghost structure of covariant string theories

NASA Astrophysics Data System (ADS)

Neveu, A.; Nicolai, H.; West, P.

1986-02-01

It is shown that there exists an infinite set of new symmetries of the previously given covariant string formulations. These symmetries have themselves an infinite set of hidden local symmetries and so on. A new physically equivalent further extended string action is given in which the infinite set of symmetries is most easily displayed. A quantization involving gauge fixing and ghosts of the various covariant string actions is given. permanent address: Kings College, Mathematics Department, London WC2R 2LS, UK.

Centre vortex removal restores chiral symmetry

NASA Astrophysics Data System (ADS)

Trewartha, Daniel; Kamleh, Waseem; Leinweber, Derek B.

2017-12-01

The influence of centre vortices on dynamical chiral symmetry breaking is investigated through the light hadron spectrum on the lattice. Recent studies of the quark propagator and other quantities have provided evidence that centre vortices are the fundamental objects underpinning dynamical chiral symmetry breaking in {SU}(3) gauge theory. For the first time, we use the chiral overlap fermion action to study the low-lying hadron spectrum on lattice ensembles consisting of Monte Carlo, vortex-removed, and vortex-projected gauge fields. We find that gauge field configurations consisting solely of smoothed centre vortices are capable of reproducing all the salient features of the hadron spectrum, including dynamical chiral symmetry breaking. The hadron spectrum on vortex-removed fields shows clear signals of chiral symmetry restoration at light values of the bare quark mass, while at heavy masses the spectrum is consistent with a theory of weakly interacting constituent quarks.

Monopole operators and Hilbert series of Coulomb branches of 3 d = 4 gauge theories

NASA Astrophysics Data System (ADS)

Cremonesi, Stefano; Hanany, Amihay; Zaffaroni, Alberto

2014-01-01

This paper addresses a long standing problem - to identify the chiral ring and moduli space (i.e. as an algebraic variety) on the Coulomb branch of an = 4 superconformal field theory in 2+1 dimensions. Previous techniques involved a computation of the metric on the moduli space and/or mirror symmetry. These methods are limited to sufficiently small moduli spaces, with enough symmetry, or to Higgs branches of sufficiently small gauge theories. We introduce a simple formula for the Hilbert series of the Coulomb branch, which applies to any good or ugly three-dimensional = 4 gauge theory. The formula counts monopole operators which are dressed by classical operators, the Casimir invariants of the residual gauge group that is left unbroken by the magnetic flux. We apply our formula to several classes of gauge theories. Along the way we make various tests of mirror symmetry, successfully comparing the Hilbert series of the Coulomb branch with the Hilbert series of the Higgs branch of the mirror theory.

Generators of dynamical symmetries and the correct gauge transformation in the Landau level problem: use of pseudomomentum and pseudo-angular momentum

NASA Astrophysics Data System (ADS)

Konstantinou, Georgios; Moulopoulos, Konstantinos

2016-11-01

Due to the importance of gauge symmetry in all fields of physics, and motivated by an article written almost three decades ago that warns against a naive handling of gauge transformations in the Landau level problem (a quantum electron moving in a spatially uniform magnetic field), we point out a proper use of the generators of dynamical symmetries combined with gauge transformation methods to easily obtain exact analytical solutions for all Landau level-wavefunctions in arbitrary gauge. Our method is different from the old argument and provides solutions in an easier manner and in a broader set of geometries and gauges; in so doing, it eliminates the need for extra procedures (i.e. a change of basis) pointed out as a necessary step in the old literature, and gives back the standard simple result, provided that an appropriate use is made of the dynamical symmetries of the system and their generators. In this way the present work will at least be useful for university-level education, i.e. in advanced classes in quantum mechanics and condensed matter physics. In addition, it clarifies the actual role of the gauge in the Landau level problem, which often appears confusing in the usual derivations provided in textbooks. Finally, we go further by showing that a similar methodology can be made to apply to the more difficult case of a spatially non-uniform magnetic field (where closed analytical results are rare), in which case the various generators (pseudomomentum and pseudo-angular momentum) appear as line integrals of the inhomogeneous magnetic field; we give closed analytical solutions for all cases, and show how the old and rather forgotten Bawin-Burnel gauge shows up naturally as a ‘reference gauge’ in all solutions.

Phenomenology of strongly coupled chiral gauge theories

DOE PAGES

Bai, Yang; Berger, Joshua; Osborne, James; ...

2016-11-25

A sector with QCD-like strong dynamics is common in models of non-standard physics. Such a model could be accessible in LHC searches if both confinement and big-quarks charged under the confining group are at the TeV scale. Big-quark masses at this scale can be explained if the new fermions are chiral under a new U(1)' gauge symmetry such that their bare masses are related to the U(1)'-breaking and new confinement scales. Here we present a study of a minimal GUT-motivated and gauge anomaly-free model with implications for the LHC Run 2 searches. We find that the first signatures of suchmore » models could appear as two gauge boson resonances. The chiral nature of the model could be confirmed by observation of a Z'γ resonance, where the Z' naturally has a large leptonic branching ratio because of its kinetic mixing with the hypercharge gauge boson.« less

Gravitational matter-antimatter asymmetry and four-dimensional Yang-Mills gauge symmetry

NASA Technical Reports Server (NTRS)

Hsu, J. P.

1981-01-01

A formulation of gravity based on the maximum four-dimensional Yang-Mills gauge symmetry is studied. The theory predicts that the gravitational force inside matter (fermions) is different from that inside antimatter. This difference could lead to the cosmic separation of matter and antimatter in the evolution of the universe. Moreover, a new gravitational long-range spin-force between two fermions is predicted, in addition to the usual Newtonian force. The geometrical foundation of such a gravitational theory is the Riemann-Cartan geometry, in which there is a torsion. The results of the theory for weak fields are consistent with previous experiments.

Neutrino cosmology after WMAP 7-year data and LHC first Z' bounds.

PubMed

Anchordoqui, Luis Alfredo; Goldberg, Haim

2012-02-24

The gauge-extended U(1)(C)×SU(2)(L)×U(1)(I(R))×U(1)(L) model elevates the global symmetries of the standard model (baryon number B and lepton number L) to local gauge symmetries. The U(1)(L) symmetry leads to three superweakly interacting right-handed neutrinos. This also renders a B-L symmetry nonanomalous. The superweak interactions of these Dirac states permit ν(R) decoupling just above the QCD phase transition: 175 is < or approximately equal to T(ν(R))(dec)/MeV is < or approximately equal to 250. In this transitional region, the residual temperature ratio between ν(L) and ν(R) generates extra relativistic degrees of freedom at BBN and at the CMB epochs. Consistency with both WMAP 7-year data and recent estimates of the primordial 4He mass fraction is achieved for 3

Non Abelian T-duality in Gauged Linear Sigma Models

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bizet, Nana Cabo; Martínez-Merino, Aldo; Zayas, Leopoldo A. Pando

Abelian T-duality in Gauged Linear Sigma Models (GLSM) forms the basis of the physical understanding of Mirror Symmetry as presented by Hori and Vafa. We consider an alternative formulation of Abelian T-duality on GLSM’s as a gauging of a global U(1) symmetry with the addition of appropriate Lagrange multipliers. For GLSMs with Abelian gauge groups and without superpotential we reproduce the dual models introduced by Hori and Vafa. We extend the construction to formulate non-Abelian T-duality on GLSMs with global non-Abelian symmetries. The equations of motion that lead to the dual model are obtained for a general group, they dependmore » in general on semi-chiral superfields; for cases such as SU(2) they depend on twisted chiral superfields. We solve the equations of motion for an SU(2) gauged group with a choice of a particular Lie algebra direction of the vector superfield. This direction covers a non-Abelian sector that can be described by a family of Abelian dualities. The dual model Lagrangian depends on twisted chiral superfields and a twisted superpotential is generated. We explore some non-perturbative aspects by making an Ansatz for the instanton corrections in the dual theories. We verify that the effective potential for the U(1) field strength in a fixed configuration on the original theory matches the one of the dual theory. Imposing restrictions on the vector superfield, more general non-Abelian dual models are obtained. We analyze the dual models via the geometry of their susy vacua.« less

Non Abelian T-duality in Gauged Linear Sigma Models

NASA Astrophysics Data System (ADS)

Bizet, Nana Cabo; Martínez-Merino, Aldo; Zayas, Leopoldo A. Pando; Santos-Silva, Roberto

2018-04-01

Abelian T-duality in Gauged Linear Sigma Models (GLSM) forms the basis of the physical understanding of Mirror Symmetry as presented by Hori and Vafa. We consider an alternative formulation of Abelian T-duality on GLSM's as a gauging of a global U(1) symmetry with the addition of appropriate Lagrange multipliers. For GLSMs with Abelian gauge groups and without superpotential we reproduce the dual models introduced by Hori and Vafa. We extend the construction to formulate non-Abelian T-duality on GLSMs with global non-Abelian symmetries. The equations of motion that lead to the dual model are obtained for a general group, they depend in general on semi-chiral superfields; for cases such as SU(2) they depend on twisted chiral superfields. We solve the equations of motion for an SU(2) gauged group with a choice of a particular Lie algebra direction of the vector superfield. This direction covers a non-Abelian sector that can be described by a family of Abelian dualities. The dual model Lagrangian depends on twisted chiral superfields and a twisted superpotential is generated. We explore some non-perturbative aspects by making an Ansatz for the instanton corrections in the dual theories. We verify that the effective potential for the U(1) field strength in a fixed configuration on the original theory matches the one of the dual theory. Imposing restrictions on the vector superfield, more general non-Abelian dual models are obtained. We analyze the dual models via the geometry of their susy vacua.

Non Abelian T-duality in Gauged Linear Sigma Models

DOE PAGES

Bizet, Nana Cabo; Martínez-Merino, Aldo; Zayas, Leopoldo A. Pando; ...

2018-04-01

Abelian T-duality in Gauged Linear Sigma Models (GLSM) forms the basis of the physical understanding of Mirror Symmetry as presented by Hori and Vafa. We consider an alternative formulation of Abelian T-duality on GLSM’s as a gauging of a global U(1) symmetry with the addition of appropriate Lagrange multipliers. For GLSMs with Abelian gauge groups and without superpotential we reproduce the dual models introduced by Hori and Vafa. We extend the construction to formulate non-Abelian T-duality on GLSMs with global non-Abelian symmetries. The equations of motion that lead to the dual model are obtained for a general group, they dependmore » in general on semi-chiral superfields; for cases such as SU(2) they depend on twisted chiral superfields. We solve the equations of motion for an SU(2) gauged group with a choice of a particular Lie algebra direction of the vector superfield. This direction covers a non-Abelian sector that can be described by a family of Abelian dualities. The dual model Lagrangian depends on twisted chiral superfields and a twisted superpotential is generated. We explore some non-perturbative aspects by making an Ansatz for the instanton corrections in the dual theories. We verify that the effective potential for the U(1) field strength in a fixed configuration on the original theory matches the one of the dual theory. Imposing restrictions on the vector superfield, more general non-Abelian dual models are obtained. We analyze the dual models via the geometry of their susy vacua.« less

Nonminimal quartic inflation in classically conformal U(1 ) X extended standard model

NASA Astrophysics Data System (ADS)

Oda, Satsuki; Okada, Nobuchika; Raut, Digesh; Takahashi, Dai-suke

2018-03-01

We propose quartic inflation with nonminimal gravitational coupling in the context of the classically conformal U(1 ) X extension of the standard model (SM). In this model, the U(1 ) X gauge symmetry is radiatively broken through the Coleman-Weinberg mechanism, by which the U(1 ) X gauge boson (Z' boson) and the right-handed Majorana neutrinos acquire their masses. We consider their masses in the range of O (10 GeV )-O (10 TeV ) , which are accessible to high-energy collider experiments. The radiative U(1 ) X gauge symmetry breaking also generates a negative mass squared for the SM Higgs doublet, and the electroweak symmetry breaking occurs subsequently. We identify the U(1 ) X Higgs field with inflaton and calculate the inflationary predictions. Because of the Coleman-Weinberg mechanism, the inflaton quartic coupling during inflation, which determines the inflationary predictions, is correlated to the U(1 ) X gauge coupling. With this correlation, we investigate complementarities between the inflationary predictions and the current constraint from the Z' boson resonance search at the LHC Run 2 as well as the prospect of the search for the Z' boson and the right-handed neutrinos at the future collider experiments.

Torsion in gauge theory

NASA Astrophysics Data System (ADS)

Nieh, H. T.

2018-02-01

The potential conflict between torsion and gauge symmetry in the Riemann-Cartan curved spacetime was noted by Kibble in his 1961 pioneering paper and has since been discussed by many authors. Kibble suggested that, to preserve gauge symmetry, one should forgo the covariant derivative in favor of the ordinary derivative in the definition of the field strength Fμ ν for massless gauge theories, while for massive vector fields, covariant derivatives should be adopted. This view was further emphasized by Hehl et al. in their influential 1976 review paper. We address the question of whether this deviation from normal procedure by forgoing covariant derivatives in curved spacetime with torsion could give rise to inconsistencies in the theory, such as the quantum renormalizability of a realistic interacting theory. We demonstrate in this paper the one-loop renormalizability of a realistic gauge theory of gauge bosons interacting with Dirac spinors, such as the SU(3) chromodynamics, for the case of a curved Riemann-Cartan spacetime with totally antisymmetric torsion. This affirmative confirmation is one step toward providing justification for the assertion that the flat-space definition of the gauge-field strength should be adopted as the proper definition.

The ATLAS diboson resonance in non-supersymmetric SO(10)

DOE PAGES

Evans, Jason L.; Nagata, Natsumi; Olive, Keith A.; ...

2016-02-18

SO(10) grand uni cation accommodates intermediate gauge symmetries with which gauge coupling uni cation can be realized without supersymmetry. In this paper, we discuss the possibility that a new massive gauge boson associated with an intermediate gauge symmetry explains the excess observed in the diboson resonance search recently reported by the ATLAS experiment. The model we find has two intermediate symmetries, SU(4) C Ⓧ SU(2) L Ⓧ SU(2) R and SU(3) C Ⓧ SU(2) L Ⓧ SU(2)R Ⓧ U(1) B-L, where the latter gauge group is broken at the TeV scale. This model achieves gauge coupling uni cation with amore » uni cation scale su fficiently high to avoid proton decay. In addition, this model provides a good dark matter candidates, whose stability is guaranteed by a Z 2 symmetry present after the spontaneous breaking of the intermediate gauge symmetries. In addition, we discuss prospects for testing these models in the forthcoming LHC experiments and dark matter detection experiments.« less

Centre vortex removal restores chiral symmetry

DOE PAGES

Trewartha, Daniel; Kamleh, Waseem; Leinweber, Derek B.

2017-11-15

The influence of centre vortices on dynamical chiral symmetry breaking is investigated through the light hadron spectrum on the lattice. Recent studies of the quark propagator and other quantities have provided evidence that centre vortices are the fundamental objects underpinning dynamical chiral symmetry breaking in SU(3) gauge theory. For the first time, we use the chiral overlap fermion action to study the low-lying hadron spectrum on lattice ensembles consisting of Monte Carlo, vortex-removed, and vortex-projected gauge fields. We find that gauge field configurations consisting solely of smoothed centre vortices are capable of reproducing all the salient features of the hadronmore » spectrum, including dynamical chiral symmetry breaking. In conclusion, the hadron spectrum on vortex-removed fields shows clear signals of chiral symmetry restoration at light values of the bare quark mass, while at heavy masses the spectrum is consistent with a theory of weakly-interacting constituent quarks.« less

Gauge symmetries of the free supersymmetric string field theories

NASA Astrophysics Data System (ADS)

Neveu, A.; West, P. C.

1985-12-01

The gauge covariant local formulations of the free supersymmetric strings that contained a finite number of supplementary fields are extended so as to place all the generators of the Ramond-Neveu-Schwarz algebra on a more equal footing. Permanent address: King's College, Mathematics Department, London WC2R 2LS, UK.

General relativity as the effective theory of GL(4,R) spontaneous symmetry breaking

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tomboulis, E. T.

2011-10-15

We assume a GL(4,R) space-time symmetry which is spontaneously broken to SO(3,1). We carry out the coset construction of the effective theory for the nonlinearly realized broken symmetry in terms of the Goldstone fields and matter fields transforming linearly under the unbroken Lorentz subgroup. We then identify functions of the Goldstone and matter fields that transform linearly also under the broken symmetry. Expressed in terms of these quantities the effective theory reproduces the vierbein formalism of general relativity with general coordinate invariance being automatically realized nonlinearly over GL(4,R). The coset construction makes no assumptions about any underlying theory that mightmore » be responsible for the assumed symmetry breaking. We give a brief discussion of the possibility of field theories with GL(4,R) rather than Lorentz space-time symmetry providing the underlying dynamics.« less

SU(2)×U(1) gauge invariance and the shape of new physics in rare B decays.

PubMed

Alonso, R; Grinstein, B; Martin Camalich, J

2014-12-12

New physics effects in B decays are routinely modeled through operators invariant under the strong and electromagnetic gauge symmetries. Assuming the scale for new physics is well above the electroweak scale, we further require invariance under the full standard model gauge symmetry group. Retaining up to dimension-six operators, we unveil new constraints between different new physics operators that are assumed to be independent in the standard phenomenological analyses. We illustrate this approach by analyzing the constraints on new physics from rare B(q) (semi-)leptonic decays.

Gauge coupling unification and nonequilibrium thermal dark matter.

PubMed

Mambrini, Yann; Olive, Keith A; Quevillon, Jérémie; Zaldívar, Bryan

2013-06-14

We study a new mechanism for the production of dark matter in the Universe which does not rely on thermal equilibrium. Dark matter is populated from the thermal bath subsequent to inflationary reheating via a massive mediator whose mass is above the reheating scale T(RH). To this end, we consider models with an extra U(1) gauge symmetry broken at some intermediate scale (M(int) ≃ 10(10)-10(12) GeV). We show that not only does the model allow for gauge coupling unification (at a higher scale associated with grand unification) but it can provide a dark matter candidate which is a standard model singlet but charged under the extra U(1). The intermediate scale gauge boson(s) which are predicted in several E6/SO(10) constructions can be a natural mediator between dark matter and the thermal bath. We show that the dark matter abundance, while never having achieved thermal equilibrium, is fixed shortly after the reheating epoch by the relation T(RH)(3)/M(int)(4). As a consequence, we show that the unification of gauge couplings which determines M(int) also fixes the reheating temperature, which can be as high as T(RH) ≃ 10(11) GeV.

Symmetries, supersymmetries and cohomologies in gauge theories

NASA Astrophysics Data System (ADS)

Bǎbǎlîc, Elena-Mirela

2009-12-01

The main subjects approached in the thesis are the following: a) the derivation of the interactions in two space-time dimensions in a particular class of topological BF models; b) the construction of the couplings in D ≥ 5 dimensions between one massless tensor field with the mixed symmetry (3, 1) and one with the mixed symmetry of the Riemann tensor; c) the evaluation of the existence of interactions in D ≥ 5 dimensions between two different collections of massless tensor fields with the mixed symmetries (3, 1) and (2, 2); d) the analysis of the relation between the BRST charges obtained in the pure-spinor formalism, respectively in the κ-symmetric one for the supermembrane in eleven dimensions. Our procedure for the first three subjects is based on solving the equations that describe the deformation of the solution to the master equation by means of specific cohomological techniques, while for the fourth one we will use techniques specific to the BRST Hamiltonian approach in order to write the BRST charge. The interactions are obtained under the following hypotheses: locality, Lorentz covariance, Poincare invariance, analyticity of the deformations, and preservation of the number of derivatives on each field. The first three assumptions imply that the interacting theory is local in space-time, Lorentz covariant and Poincare invariant. The analyticity of the deformations refers to the fact that the deformed solution to the master equation is analytical in the coupling constant and reduces to the original solution in the free limit. The conservation of the number of derivatives on each field with respect to the free theory means here that the following two requirements are simultaneously satisfied: (i) the derivative order of the equations of motion on each field is the same for the free and respectively for the interacting theory; (ii) the maximum number of derivatives in the interaction vertices is equal to two, i.e. the maximum number of derivatives from

Ward identity and basis tensor gauge theory at one loop

NASA Astrophysics Data System (ADS)

Chung, Daniel J. H.

2018-06-01

Basis tensor gauge theory (BTGT) is a reformulation of ordinary gauge theory that is an analog of the vierbein formulation of gravity and is related to the Wilson line formulation. To match ordinary gauge theories coupled to matter, the BTGT formalism requires a continuous symmetry that we call the BTGT symmetry in addition to the ordinary gauge symmetry. After classically interpreting the BTGT symmetry, we construct using the BTGT formalism the Ward identities associated with the BTGT symmetry and the ordinary gauge symmetry. For a way of testing the quantum stability and the consistency of the Ward identities with a known regularization method, we explicitly renormalize the scalar QED at one loop using dimensional regularization using the BTGT formalism.

Gauge symmetries of the free bosonic string field theory

NASA Astrophysics Data System (ADS)

Neveu, A.; Schwarz, J.; West, P. C.

1985-12-01

The gauge covariant local formulations of free bosonic string theories that contained a finite number of supplementary fields are extended to include an infinite number of supplementary fields. These new formulations allow the generators of the Virasoro algebra to appear on a more equal footing. Permanent address: King's College, Physics Department, London WC2R 2LS, UK.

" L = R" - U(1) R lepton number at the LHC

NASA Astrophysics Data System (ADS)

Frugiuele, Claudia; Grégoire, Thomas; Kumar, Piyush; Pontón, Eduardo

2013-05-01

We perform a detailed study of a variety of LHC signals in supersymmetric models where lepton number is promoted to an (approximate) U(1) R symmetry. Such a symmetry has interesting implications for naturalness, as well as flavor- and CP-violation, among others. Interestingly, it makes large sneutrino vacuum expectation values phenomenologically viable, so that a slepton doublet can play the role of the down-type Higgs. As a result, (some of) the leptons and neutrinos are incorporated into the chargino and neutralino sectors. This leads to characteristic decay patterns that can be experimentally tested at the LHC. The corresponding collider phenomenology is largely determined by the new approximately conserved quantum number, which is itself closely tied to the presence of "leptonic R-parity violation". We find rather loose bounds on the first and second generation squarks, arising from a combination of suppressed production rates together with relatively small signal efficiencies of the current searches. Naturalness would indicate that such a framework should be discovered in the near future, perhaps through spectacular signals exhibiting the lepto-quark nature of the third generation squarks. The presence of fully visible decays, in addition to decay chains involving large missing energy (in the form of neutrinos) could give handles to access the details of the spectrum of new particles, if excesses over SM background were to be observed. The scale of neutrino masses is intimately tied to the source of U(1) R breaking, thus opening a window into the R-breaking sector through neutrino physics. Further theoretical aspects of the model have been presented in the companion paper [1].

Generalization of Faddeev-Popov rules in Yang-Mills theories: N = 3,4 BRST symmetries

NASA Astrophysics Data System (ADS)

Reshetnyak, Alexander

2018-01-01

The Faddeev-Popov rules for a local and Poincaré-covariant Lagrangian quantization of a gauge theory with gauge group are generalized to the case of an invariance of the respective quantum actions, S(N), with respect to N-parametric Abelian SUSY transformations with odd-valued parameters λp, p = 1,…,N and generators sp: spsq + sqsp = 0, for N = 3, 4, implying the substitution of an N-plet of ghost fields, Cp, instead of the parameter, ξ, of infinitesimal gauge transformations: ξ = Cpλ p. The total configuration spaces of fields for a quantum theory of the same classical model coincide in the N = 3 and N = 4 symmetric cases. The superspace of N = 3 SUSY irreducible representation includes, in addition to Yang-Mills fields 𝒜μ, (3 + 1) ghost odd-valued fields Cp, B̂ and 3 even-valued Bpq for p, q = 1, 2, 3. To construct the quantum action, S(3), by adding to the classical action, S0(𝒜), of an N = 3-exact gauge-fixing term (with gauge fermion), a gauge-fixing procedure requires (1 + 3 + 3 + 1) additional fields, Φ¯(3): antighost C¯, 3 even-valued Bp, 3 odd-valued B̂pq and Nakanishi-Lautrup B fields. The action of N = 3 transformations on new fields as N = 3-irreducible representation space is realized. These transformations are the N = 3 BRST symmetry transformations for the vacuum functional, Z3(0) =∫dΦ(3)dΦ¯(3)exp{(ı/ℏ)S(3)}. The space of all fields (Φ(3),Φ¯(3)) proves to be the space of an irreducible representation of the fields Φ(4) for N = 4-parametric SUSY transformations, which contains, in addition to 𝒜μ the (4 + 6 + 4 + 1) ghost-antighost, Cr = (Cp,C¯), even-valued, Brs = -Bsr = (Bpq,Bp4 = Bp), odd-valued B̂r = (B̂,B̂pq) and B fields. The quantum action is constructed by adding to S0(𝒜) an N = 4-exact gauge-fixing term with a gauge boson, F(4). The N = 4 SUSY transformations are by N = 4 BRST transformations for the vacuum functional, Z4(0) =∫dΦ(4)exp{(ı/ℏ)S(4)}. The procedures are valid for

Determining triple gauge boson couplings from Higgs data.

PubMed

Corbett, Tyler; Éboli, O J P; Gonzalez-Fraile, J; Gonzalez-Garcia, M C

2013-07-05

In the framework of effective Lagrangians with the SU(2)(L)×U(1)(Y) symmetry linearly realized, modifications of the couplings of the Higgs field to the electroweak gauge bosons are related to anomalous triple gauge couplings (TGCs). Here, we show that the analysis of the latest Higgs boson production data at the LHC and Tevatron give rise to strong bounds on TGCs that are complementary to those from direct TGC analysis. We present the constraints on TGCs obtained by combining all available data on direct TGC studies and on Higgs production analysis.

Quantization of Spontaneously Broken Gauge Theory Based on the Bft-Bfv Formalism

NASA Astrophysics Data System (ADS)

Kim, Yong-Wan; Park, Young-Jai

We quantize the spontaneously broken Abelian U(1) Higgs model by using the improved BFT and BFV formalisms. We construct the BFT physical fields and obtain the firstclass observables including the Hamiltonian in terms of these fields. We also explicitly show that there are exact form invariances between the second-class and first-class quantities. Then, according to the BFV formalism, we derive the corresponding Lagrangian having U(1) gauge symmetry. We also discuss at the classical level how one easily gets the first-class Lagrangian from the symmetry-broken second-class Lagrangian.

Mirror symmetry in emergent gravity

NASA Astrophysics Data System (ADS)

Yang, Hyun Seok

2017-09-01

Given a six-dimensional symplectic manifold (M , B), a nondegenerate, co-closed four-form C introduces a dual symplectic structure B ˜ = * C independent of B via the Hodge duality *. We show that the doubling of symplectic structures due to the Hodge duality results in two independent classes of noncommutative U (1) gauge fields by considering the Seiberg-Witten map for each symplectic structure. As a result, emergent gravity suggests a beautiful picture that the variety of six-dimensional manifolds emergent from noncommutative U (1) gauge fields is doubled. In particular, the doubling for the variety of emergent Calabi-Yau manifolds allows us to arrange a pair of Calabi-Yau manifolds such that they are mirror to each other. Therefore, we argue that the mirror symmetry of Calabi-Yau manifolds is the Hodge theory for the deformation of symplectic and dual symplectic structures.

Generalized global symmetries

DOE PAGES

Gaiotto, Davide; Kapustin, Anton; Seiberg, Nathan; ...

2015-02-26

A q-form global symmetry is a global symmetry for which the charged operators are of space-time dimension q; e.g. Wilson lines, surface defects, etc., and the charged excitations have q spatial dimensions; e.g. strings, membranes, etc. Many of the properties of ordinary global symmetries (q = 0) apply here. They lead to Ward identities and hence to selection rules on amplitudes. Such global symmetries can be coupled to classical background fields and they can be gauged by summing over these classical fields. These generalized global symmetries can be spontaneously broken (either completely or to a sub-group). They can also havemore » ’t Hooft anomalies, which prevent us from gauging them, but lead to ’t Hooft anomaly matching conditions. Such anomalies can also lead to anomaly inflow on various defects and exotic Symmetry Protected Topological phases. In conclusion, our analysis of these symmetries gives a new unified perspective of many known phenomena and uncovers new results.« less

Asymptotically Free Gauge Theories. I

DOE R&D Accomplishments Database

Wilczek, Frank; Gross, David J.

1973-07-01

Asymptotically free gauge theories of the strong interactions are constructed and analyzed. The reasons for doing this are recounted, including a review of renormalization group techniques and their application to scaling phenomena. The renormalization group equations are derived for Yang-Mills theories. The parameters that enter into the equations are calculated to lowest order and it is shown that these theories are asymptotically free. More specifically the effective coupling constant, which determines the ultraviolet behavior of the theory, vanishes for large space-like momenta. Fermions are incorporated and the construction of realistic models is discussed. We propose that the strong interactions be mediated by a "color" gauge group which commutes with SU(3)xSU(3). The problem of symmetry breaking is discussed. It appears likely that this would have a dynamical origin. It is suggested that the gauge symmetry might not be broken, and that the severe infrared singularities prevent the occurrence of non-color singlet physical states. The deep inelastic structure functions, as well as the electron position total annihilation cross section are analyzed. Scaling obtains up to calculable logarithmic corrections, and the naive lightcone or parton model results follow. The problems of incorporating scalar mesons and breaking the symmetry by the Higgs mechanism are explained in detail.

Spin-rotation symmetry breaking and triplet superconducting state in doped topological insulator CuxBi2Se3

NASA Astrophysics Data System (ADS)

Zheng, Guo-Qing

Spontaneous symmetry breaking is an important concept for understanding physics ranging from the elementary particles to states of matter. For example, the superconducting state breaks global gauge symmetry, and unconventional superconductors can break additional symmetries. In particular, spin rotational symmetry is expected to be broken in spin-triplet superconductors. However, experimental evidence for such symmetry breaking has not been obtained so far in any candidate compounds. We report 77Se nuclear magnetic resonance measurements which showed that spin rotation symmetry is spontaneously broken in the hexagonal plane of the electron-doped topological insulator Cu0.3Bi2Se3 below the superconducting transition temperature Tc =3.4 K. Our results not only establish spin-triplet (odd parity) superconductivity in this compound, but also serve to lay a foundation for the research of topological superconductivity (Ref.). We will also report the doping mechanism and superconductivity in Sn1-xInxTe.

On N = 1 partition functions without R-symmetry

DOE PAGES

Knodel, Gino; Liu, James T.; Zayas, Leopoldo A. Pando

2015-03-25

Here, we examine the dependence of four-dimensional Euclidean N = 1 partition functions on coupling constants. In particular, we focus on backgrounds without R-symmetry, which arise in the rigid limit of old minimal supergravity. Backgrounds preserving a single supercharge may be classified as having either trivial or SU(2) structure, with the former including S 4. We show that, in the absence of additional symmetries, the partition function depends non-trivially on all couplings in the trivial structure case, and (anti)-holomorphically on couplings in the SU(2) structure case. In both cases, this allows for ambiguities in the form of finite counterterms, whichmore » in principle render the partition function unphysical. However, we argue that on dimensional grounds, ambiguities are restricted to finite powers in relevant couplings, and can therefore be kept under control. On the other hand, for backgrounds preserving supercharges of opposite chiralities, the partition function is completely independent of all couplings. In this case, the background admits an R-symmetry, and the partition function is physical, in agreement with the results obtained in the rigid limit of new minimal supergravity. Based on a systematic analysis of supersymmetric invariants, we also demonstrate that N = 1 localization is not possible for backgrounds without R-symmetry.« less

General U(1)×U(1) F-theory compactifications and beyond: geometry of unHiggsings and novel matter structure

DOE PAGES

Cvetic, Mirjam; Klevers, Denis; Piragua, Hernan; ...

2015-11-30

We construct the general form of an F-theory compactification with two U(1) factors based on a general elliptically fibered Calabi-Yau manifold with Mordell-Weil group of rank two. This construction produces broad classes of models with diverse matter spectra, including many that are not realized in earlier F-theory constructions with U(1)×U(1) gauge symmetry. Generic U(1)×U(1) models can be related to a Higgsed non-Abelian model with gauge group SU(2)×SU(2)×SU(3), SU(2) 3×SU(3), or a subgroup thereof. The nonlocal horizontal divisors of the Mordell-Weil group are replaced with local vertical divisors associated with the Cartan generators of non-Abelian gauge groups from Kodaira singularities. Wemore » give a global resolution of codimension two singularities of the Abelian model; we identify the full anomaly free matter content, and match it to the unHiggsed non-Abelian model. The non-Abelian Weierstrass model exhibits a new algebraic description of the singularities in the fibration that results in the first explicit construction of matter in the symmetric representation of SU(3). This matter is realized on double point singularities of the discriminant locus. In conclusion, the construction suggests a generalization to U(1) k factors with k > 2, which can be studied by Higgsing theories with larger non-Abelian gauge groups.« less

Asymptotic symmetries, holography and topological hair

NASA Astrophysics Data System (ADS)

Mishra, Rashmish K.; Sundrum, Raman

2018-01-01

Asymptotic symmetries of AdS4 quantum gravity and gauge theory are derived by coupling the holographically dual CFT3 to Chern-Simons gauge theory and 3D gravity in a "probe" (large-level) limit. Despite the fact that the three-dimensional AdS4 boundary as a whole is consistent with only finite-dimensional asymptotic symmetries, given by AdS isometries, infinite-dimensional symmetries are shown to arise in circumstances where one is restricted to boundary subspaces with effectively two-dimensional geometry. A canonical example of such a restriction occurs within the 4D subregion described by a Wheeler-DeWitt wavefunctional of AdS4 quantum gravity. An AdS4 analog of Minkowski "super-rotation" asymptotic symmetry is probed by 3D Einstein gravity, yielding CFT2 structure (in a large central charge limit), via AdS3 foliation of AdS4 and the AdS3/CFT2 correspondence. The maximal asymptotic symmetry is however probed by 3D conformal gravity. Both 3D gravities have Chern-Simons formulation, manifesting their topological character. Chern-Simons structure is also shown to be emergent in the Poincare patch of AdS4, as soft/boundary limits of 4D gauge theory, rather than "put in by hand" as an external probe. This results in a finite effective Chern-Simons level. Several of the considerations of asymptotic symmetry structure are found to be simpler for AdS4 than for Mink4, such as non-zero 4D particle masses, 4D non-perturbative "hard" effects, and consistency with unitarity. The last of these in particular is greatly simplified because in some set-ups the time dimension is explicitly shared by each level of description: Lorentzian AdS4, CFT3 and CFT2. Relatedly, the CFT2 structure clarifies the sense in which the infinite asymptotic charges constitute a useful form of "hair" for black holes and other complex 4D states. An AdS4 analog of Minkowski "memory" effects is derived, but with late-time memory of earlier events being replaced by (holographic) "shadow" effects. Lessons

Loop Braiding Statistics and Interacting Fermionic Symmetry-Protected Topological Phases in Three Dimensions

NASA Astrophysics Data System (ADS)

Cheng, Meng; Tantivasadakarn, Nathanan; Wang, Chenjie

2018-01-01

We study Abelian braiding statistics of loop excitations in three-dimensional gauge theories with fermionic particles and the closely related problem of classifying 3D fermionic symmetry-protected topological (FSPT) phases with unitary symmetries. It is known that the two problems are related by turning FSPT phases into gauge theories through gauging the global symmetry of the former. We show that there exist certain types of Abelian loop braiding statistics that are allowed only in the presence of fermionic particles, which correspond to 3D "intrinsic" FSPT phases, i.e., those that do not stem from bosonic SPT phases. While such intrinsic FSPT phases are ubiquitous in 2D systems and in 3D systems with antiunitary symmetries, their existence in 3D systems with unitary symmetries was not confirmed previously due to the fact that strong interaction is necessary to realize them. We show that the simplest unitary symmetry to support 3D intrinsic FSPT phases is Z2×Z4. To establish the results, we first derive a complete set of physical constraints on Abelian loop braiding statistics. Solving the constraints, we obtain all possible Abelian loop braiding statistics in 3D gauge theories, including those that correspond to intrinsic FSPT phases. Then, we construct exactly soluble state-sum models to realize the loop braiding statistics. These state-sum models generalize the well-known Crane-Yetter and Dijkgraaf-Witten models.

To gauge or not to gauge?

NASA Astrophysics Data System (ADS)

Maldacena, Juan; Milekhin, Alexey

2018-04-01

The D0 brane, or BFSS, matrix model is a quantum mechanical theory with an interesting gravity dual. We consider a variant of this model where we treat the SU( N) symmetry as a global symmetry, rather than as a gauge symmetry. This variant contains new non-singlet states. We consider the impact of these new states on its gravity dual. We argue that the gravity dual is essentially the same as the one for the original matrix model. The non-singlet states have higher energy at strong coupling and are therefore dynamically suppressed.

(3+1)-Dimensional topologically massive 2-form gauge theory: geometrical superfield approach

NASA Astrophysics Data System (ADS)

Kumar, R.; Mukhopadhyay, Debmalya

2018-06-01

We derive the complete set of off-shell nilpotent and absolutely anticommuting Becchi-Rouet-Stora-Tyutin (BRST) and anti-BRST symmetry transformations corresponding to the combined "scalar" and "vector" gauge symmetry transformations for the (3+1)-dimensional (4D) topologically massive non-Abelian (B \\wedge F) theory with the help of geometrical superfield formalism. For this purpose, we use three horizontality conditions (HCs). The first HC produces the (anti-)BRST transformations for the 1-form gauge field and corresponding (anti-)ghost fields whereas the second HC yields the (anti-)BRST transformations for 2-form field and associated (anti-)ghost fields. The integrability of second HC produces third HC. The latter HC produces the (anti-)BRST symmetry transformations for the compensating auxiliary vector field and corresponding ghosts. We obtain five (anti-)BRST invariant Curci-Ferrari (CF)-type conditions which emerge very naturally as the off-shoots of superfield formalism. Out of five CF-type conditions, two are fermionic in nature. These CF-type conditions play a decisive role in providing the absolute anticommutativity of the (anti-)BRST transformations and also responsible for the derivation of coupled but equivalent (anti-)BRST invariant Lagrangian densities. Furthermore, we capture the (anti-)BRST invariance of the coupled Lagrangian densities in terms of the superfields and translation generators along the Grassmannian directions θ and \\bar{θ }.

Symmetry restored in dibosons at the LHC?

DOE PAGES

Brehmer, Johann; Hewett, JoAnne; Kopp, Joachim; ...

2015-10-28

A number of LHC resonance search channels display an excess in the invariant mass region of 1.8–2.0 TeV. Among them is a 3.4σ excess in the fully hadronic decay of a pair of Standard Model electroweak gauge bosons, in addition to potential signals in the HW and dijet final states. We perform a model-independent cross-section fit to the results of all ATLAS and CMS searches sensitive to these final states. We then interpret these results in the context of the Left-Right Symmetric Model, based on the extended gauge group SU(2) L × SU(2) R × U(1)', and show that amore » heavy right-handed gauge boson W R can naturally explain the current measurements with just a single coupling g R ~ 0.4. Thus, we discuss a possible connection to dark matter.« less

Gauged multisoliton baby Skyrme model

NASA Astrophysics Data System (ADS)

Samoilenka, A.; Shnir, Ya.

2016-03-01

We present a study of U (1 ) gauged modification of the 2 +1 -dimensional planar Skyrme model with a particular choice of the symmetry breaking potential term which combines a short-range repulsion and a long-range attraction. In the absence of the gauge interaction, the multisolitons of the model are aloof, as they consist of the individual constituents which are well separated. A peculiar feature of the model is that there are usually several different stable static multisoliton solutions of rather similar energy in a topological sector of given degree. We investigate the pattern of the solutions and find new previously unknown local minima. It is shown that coupling of the aloof planar multi-Skyrmions to the magnetic field strongly affects the pattern of interaction between the constituents. We analyze the dependency of the structure of the solutions, their energies, and magnetic fluxes on the strength of the gauge coupling. It is found that, generically, in the strong coupling limit, the coupling to the gauge field results in effective recovery of the rotational invariance of the configuration.

The SU(3)/Z3 QCD(adj) deconfinement transition via the gauge theory/"affine" XY-model duality

NASA Astrophysics Data System (ADS)

Anber, Mohamed M.; Collier, Scott; Poppitz, Erich

2013-01-01

Earlier, two of us and M. Ünsal [1] showed that a class of 4d gauge theories, when compactified on a small spatial circle of size L and considered at temperatures β-1 near the deconfinement transition, are dual to 2d "affine" XY-spin models. We exploit this duality to study the deconfinement phase transition in SU(3)/{{{Z}}_3} gauge theories with n f > 1 massless adjoint Weyl fermions, QCD(adj) on {{{R}}^2}× {S}_{β}^1× {S}_L^1 . The dual "affine" XY-model describes two "spins" — compact scalars taking values in the SU(3) root lattice. The spins couple via nearest-neighbor interactions and are subject to an "external field" perturbation preserving the topological {Z}_3^t and a discrete {Z}_3^{{{d_{\\upchi}}}} subgroup of the anomaly-free chiral symmetry of the 4d gauge theory. The equivalent Coulomb gas representation of the theory exhibits electric-magnetic duality, which is also a high-/low-temperature duality. A renormalization group analysis suggests — but is not convincing, due to the onset of strong coupling — that the self-dual point is a fixed point, implying a continuous deconfinement transition. Here, we study the nature of the transition via Monte Carlo simulations. The {Z}_3^t× {Z}_3^{{{d_{\\upchi}}}} order parameter, its susceptibility, the vortex density, the energy per spin, and the specific heat are measured over a range of volumes, temperatures, and "external field" strengths (in the gauge theory, these correspond to magnetic bion fugacities). The finite-size scaling of the susceptibility and specific heat we find is characteristic of a first-order transition. Furthermore, for sufficiently large but still smaller than unity bion fugacity (as can be achieved upon an increase of the {S}_L^1 size), at the critical temperature we find two distinct peaks of the energy probability distribution, indicative of a first-order transition, as has been seen in earlier simulations of the full 4d QCD(adj) theory. We end with discussions of the global

SU(3) gauge symmetry for collective rotational states in deformed nuclei

NASA Astrophysics Data System (ADS)

Rosensteel, George; Sparks, Nick

2016-09-01

How do deformed nuclei rotate? The qualitative answer is that a velocity-dependent interaction causes a strong coupling between the angular momentum and the vortex momentum (or Kelvin circulation). To achieve a quantitative explanation, we propose a significant extension of the Bohr-Mottelson legacy model in which collective wave functions are vector-valued in an irreducible representation of SU(3). This SU(3) is not the usual Elliott choice, but rather describes internal vorticity in the rotating frame. The circulation values C of an SU(3) irreducible representation, say the (8,0) for 20Ne, are C = 0, 2, 4, 6, 8, which is the same as the angular momentum spectrum in the Elliott model; the reason is a reciprocity theorem in the symplectic model. The differential geometry of Yang-Mills theory provides a natural mathematical framework to solve the angular-vortex coupling riddle. The requisite strong coupling is a ``magnetic-like'' interaction arising from the covariant derivative and the bundle connection. The model builds on prior work about the Yang-Mills SO(3) gauge group model.

Poincaré gauge gravity: An emergent scenario

NASA Astrophysics Data System (ADS)

Chkareuli, J. L.

2017-04-01

The Poincaré gauge gravity (PGG) with the underlying vector fields of tetrads and spin-connections is perhaps the best theory candidate for gravitation to be unified with the other three elementary forces of nature. There is a clear analogy between the local frame in PGG and the local internal symmetry space in the Standard Model. As a result, the spin-connection fields, gauging the local frame Lorentz symmetry group S O (1 ,3 )LF , appear in PGG much as photons and gluons appear in SM. We propose that such an analogy may follow from their common emergent nature allowing us to derive PGG in the same way as conventional gauge theories. In essence, we start with an arbitrary theory of some vector and fermion fields which possesses only global spacetime symmetries, such as Lorentz and translational invariance, in flat Minkowski space. The two vector field multiplets involved are proposed to belong, respectively, to the adjoint (Aμi j) and vector (eμi) representations of the starting global Lorentz symmetry. We show that if these prototype vector fields are covariantly constrained, Aμi jAij μ=±MA2 and eμieiμ=±Me2 , thus causing a spontaneous violation of the accompanying global symmetries (MA ,e are their proposed violation scales), then the only possible theory compatible with these length-preserving constraints is turned out to be the gauge invariant PGG, while the corresponding massless (pseudo)Goldstone modes are naturally collected in the emergent gauge fields of tetrads and spin-connections. In a minimal theory case being linear in a curvature we unavoidably come to the Einstein-Cartan theory. The extended theories with propagating spin-connection and tetrad modes are also considered and their possible unification with the Standard Model is briefly discussed.

Higgsless approach to electroweak symmetry breaking

NASA Astrophysics Data System (ADS)

Grojean, Christophe

2007-11-01

Higgsless models are an attempt to achieve a breaking of the electroweak symmetry via boundary conditions at the end-points of a fifth dimension compactified on an interval, as an alternative to the usual Higgs mechanism. There is no physical Higgs scalar in the spectrum and the perturbative unitarity violation scale is delayed via the exchange of massive spin-1 KK resonances. The correct mass spectrum is reproduced in a model in warped space, which inherits a custodial symmetry from a left-right gauge symmetry in the bulk. Phenomenological challenges as well as collider signatures are presented. From the AdS/CFT perspective, this model appears as a weakly coupled dual to walking technicolour models. To cite this article: C. Grojean, C. R. Physique 8 (2007).

The priority of internal symmetries in particle physics

NASA Astrophysics Data System (ADS)

Kantorovich, Aharon

2003-12-01

In this paper, I try to decipher the role of internal symmetries in the ontological maze of particle physics. The relationship between internal symmetries and laws of nature is discussed within the framework of ;Platonic realism.; The notion of physical ;structure; is introduced as representing a deeper ontological layer behind the observable world. I argue that an internal symmetry is a structure encompassing laws of nature. The application of internal symmetry groups to particle physics came about in two revolutionary steps. The first was the introduction of the internal symmetries of hadrons in the early 1960s. These global and approximate symmetries served as means of bypassing the dynamics. I argue that the realist could interpret these symmetries as ontologically prior to the hadrons. The second step was the gauge revolution in the 1970s, where symmetries became local and exact and were integrated with the dynamics. I argue that the symmetries of the second generation are fundamental in the following two respects: (1) According to the so-called ;gauge argument,; gauge symmetry dictates the existence of gauge bosons, which determine the nature of the forces. This view, which has been recently criticized by some philosophers, is widely accepted in particle physics at least as a heuristic principle. (2) In view of grand unified theories, the new symmetries can be interpreted as ontologically prior to baryon matter.

Near horizon symmetry and entropy formula for Kerr-Newman (A)dS black holes

NASA Astrophysics Data System (ADS)

Setare, Mohammad Reza; Adami, Hamed

2018-04-01

In this paper we provide the first non-trivial evidence for universality of the entropy formula 4 πJ 0 + J 0 - beyond pure Einstein gravity in 4-dimensions. We consider the Einstein-Maxwell theory in the presence of cosmological constant, then write near horizon metric of the Kerr-Newman (A)dS black hole in the Gaussian null coordinate system. We consider near horizon fall-off conditions for metric and U(1) gauge field. We find asymptotic combined symmetry generator, consists of diffeomorphism and U(1) gauge transformation, so that it preserves fall-off conditions. Consequently, we find supertranslation, supperrotation and multiple-charge modes and then we show that the entropy formula is held for the Kerr-Newman (A)dS black hole. Supperrotation modes suffer from a problem. By introducing new combined symmetry generator, we cure that problem.

Surveying the quantum group symmetries of integrable open spin chains

NASA Astrophysics Data System (ADS)

Nepomechie, Rafael I.; Retore, Ana L.

2018-05-01

Using anisotropic R-matrices associated with affine Lie algebras g ˆ (specifically, A2n(2), A2n-1 (2) , Bn(1), Cn(1), Dn(1)) and suitable corresponding K-matrices, we construct families of integrable open quantum spin chains of finite length, whose transfer matrices are invariant under the quantum group corresponding to removing one node from the Dynkin diagram of g ˆ . We show that these transfer matrices also have a duality symmetry (for the cases Cn(1) and Dn(1)) and additional Z2 symmetries that map complex representations to their conjugates (for the cases A2n-1 (2) , Bn(1) and Dn(1)). A key simplification is achieved by working in a certain "unitary" gauge, in which only the unbroken symmetry generators appear. The proofs of these symmetries rely on some new properties of the R-matrices. We use these symmetries to explain the degeneracies of the transfer matrices.

Type II string theory on Calabi-Yau manifolds with torsion and non-Abelian discrete gauge symmetries

DOE PAGES

Braun, Volker; Cvetič, Mirjam; Donagi, Ron; ...

2017-07-26

Here, we provide the first explicit example of Type IIB string theory compactication on a globally defined Calabi-Yau threefold with torsion which results in a fourdimensional effective theory with a non-Abelian discrete gauge symmetry. Our example is based on a particular Calabi-Yau manifold, the quotient of a product of three elliptic curves by a fixed point free action of Z 2 X Z 2. Its cohomology contains torsion classes in various degrees. The main technical novelty is in determining the multiplicative structure of the (torsion part of) the cohomology ring, and in particular showing that the cup product of secondmore » cohomology torsion elements goes non-trivially to the fourth cohomology. This specifies a non-Abelian, Heisenberg-type discrete symmetry group of the four-dimensional theory.« less

Type II string theory on Calabi-Yau manifolds with torsion and non-Abelian discrete gauge symmetries

DOE Office of Scientific and Technical Information (OSTI.GOV)

Braun, Volker; Cvetič, Mirjam; Donagi, Ron

Here, we provide the first explicit example of Type IIB string theory compactication on a globally defined Calabi-Yau threefold with torsion which results in a fourdimensional effective theory with a non-Abelian discrete gauge symmetry. Our example is based on a particular Calabi-Yau manifold, the quotient of a product of three elliptic curves by a fixed point free action of Z 2 X Z 2. Its cohomology contains torsion classes in various degrees. The main technical novelty is in determining the multiplicative structure of the (torsion part of) the cohomology ring, and in particular showing that the cup product of secondmore » cohomology torsion elements goes non-trivially to the fourth cohomology. This specifies a non-Abelian, Heisenberg-type discrete symmetry group of the four-dimensional theory.« less

Symmetry analysis of the behavior of the family R6M23 compounds upon hydrogenation

NASA Astrophysics Data System (ADS)

Kuna, Agnieszka; Sikora, Wiesława

2011-06-01

Symmetry analysis was applied in this work to discuss the behavior of the family R6M23 compounds upon hydrogenation (deuteration), where different structural transformations and magnetic properties, depending on the type of R and M atoms and hydrogen (deuterium) concentrations, have been found. The crystallographic structure of these compounds is described by the Fm3m space group and contain 116 atoms per unit cell occupying the positions 24e(R), 4b, 24d, 32f1 and 32f2(M). Additionally in the elementary cell, there could be up to 100 atoms of hydrogen (or deuterium) occupying the interstitial positions 4a, 32f3, 96j1 and 96k1. The symmetry analysis in the frame of the theory of space groups and their representation gives the opportunity to find all possible transformations from high symmetry parent structure to the structures with symmetry belonging to one of its subgroups. For a given transformation it indicates possible displacements of atoms from initial positions in the parent structure, ordering of hydrogen over interstitial sites and also ordering of magnetic moments, described by the smallest possible number of free parameters. The analysis was carried out by means of the MODY computer program for vectors k = (0; 0; 0) and k = (0; 0; 1) describing the changes of translational symmetry and all positions occupied by the R, M and D atoms.

Global Gauge Anomalies in Two-Dimensional Bosonic Sigma Models

NASA Astrophysics Data System (ADS)

Gawȩdzki, Krzysztof; Suszek, Rafał R.; Waldorf, Konrad

2011-03-01

We revisit the gauging of rigid symmetries in two-dimensional bosonic sigma models with a Wess-Zumino term in the action. Such a term is related to a background closed 3-form H on the target space. More exactly, the sigma-model Feynman amplitudes of classical fields are associated to a bundle gerbe with connection of curvature H over the target space. Under conditions that were unraveled more than twenty years ago, the classical amplitudes may be coupled to the topologically trivial gauge fields of the symmetry group in a way which assures infinitesimal gauge invariance. We show that the resulting gauged Wess-Zumino amplitudes may, nevertheless, exhibit global gauge anomalies that we fully classify. The general results are illustrated on the example of the WZW and the coset models of conformal field theory. The latter are shown to be inconsistent in the presence of global anomalies. We introduce a notion of equivariant gerbes that allow an anomaly-free coupling of the Wess-Zumino amplitudes to all gauge fields, including the ones in non-trivial principal bundles. Obstructions to the existence of equivariant gerbes and their classification are discussed. The choice of different equivariant structures on the same bundle gerbe gives rise to a new type of discrete-torsion ambiguities in the gauged amplitudes. An explicit construction of gerbes equivariant with respect to the adjoint symmetries over compact simply connected simple Lie groups is given.

Accurate measurement of heteronuclear dipolar couplings by phase-alternating R-symmetry (PARS) sequences in magic angle spinning NMR spectroscopy

NASA Astrophysics Data System (ADS)

Hou, Guangjin; Lu, Xingyu; Vega, Alexander J.; Polenova, Tatyana

2014-09-01

We report a Phase-Alternating R-Symmetry (PARS) dipolar recoupling scheme for accurate measurement of heteronuclear 1H-X (X = 13C, 15N, 31P, etc.) dipolar couplings in MAS NMR experiments. It is an improvement of conventional C- and R-symmetry type DIPSHIFT experiments where, in addition to the dipolar interaction, the 1H CSA interaction persists and thereby introduces considerable errors in the dipolar measurements. In PARS, phase-shifted RN symmetry pulse blocks applied on the 1H spins combined with π pulses applied on the X spins at the end of each RN block efficiently suppress the effect from 1H chemical shift anisotropy, while keeping the 1H-X dipolar couplings intact. Another advantage over conventional DIPSHIFT experiments, which require the signal to be detected in the form of a reduced-intensity Hahn echo, is that the series of π pulses refocuses the X chemical shift and avoids the necessity of echo formation. PARS permits determination of accurate dipolar couplings in a single experiment; it is suitable for a wide range of MAS conditions including both slow and fast MAS frequencies; and it assures dipolar truncation from the remote protons. The performance of PARS is tested on two model systems, [15N]-N-acetyl-valine and [U-13C,15N]-N-formyl-Met-Leu-Phe tripeptide. The application of PARS for site-resolved measurement of accurate 1H-15N dipolar couplings in the context of 3D experiments is presented on U-13C,15N-enriched dynein light chain protein LC8.

Broken S 3L×S 3R flavor symmetry and leptonic CP violation

NASA Astrophysics Data System (ADS)

Si, Zong-guo; Yang, Xing-hua; Zhou, Shun

2017-11-01

In the framework of the canonical seesaw model, we present a simple but viable scenario to explicitly break an S 3L×S 3R flavor symmetry in the leptonic sector. It turns out that the leptonic flavor mixing matrix is completely determined by the mass ratios of the charged leptons (i.e., m e/m μ and m μ/m τ) and those of light neutrinos (i.e., m 1/m 2 and m 2/m 3). The latest global-fit results of the three neutrino mixing angles {θ 12, θ 13, θ 23} and two neutrino mass-squared differences at the 3σ level are used to constrain the parameter space of {m 1/m 2,m 2/m 3}. The predictions for the mass spectrum and flavor mixing are highlighted: (1) the neutrino mass spectrum shows a hierarchical pattern and a normal ordering, e.g., m 1≈2.2 meV, m 2≈8.8 meV and m 3≈52.7 meV (2) only the first octant of θ 23 is allowed, namely, 41.8°≲θ 23≲43.3° (3) the Dirac CP-violating phase δ≈-22° deviates significantly from the maximal value -90°. All these predictions are ready to be tested in ongoing and forthcoming neutrino oscillation experiments. Moreover, we demonstrate that the cosmological matter-antimatter asymmetry can be explained via resonant leptogenesis, including the individual lepton-flavor effects. In our scenario, leptonic CP violation at low- and high-energy scales is closely connected. Supported by NNSFC (11325525), National Recruitment Program for Young Professionals and CAS Center for Excellence in Particle Physics (CCEPP)

Classification of compactified su( N c ) gauge theories with fermions in all representations

NASA Astrophysics Data System (ADS)

Anber, Mohamed M.; Vincent-Genod, Loïc

2017-12-01

We classify su( N c ) gauge theories on R^3× S^1 with massless fermions in higher representations obeying periodic boundary conditions along S^1 . In particular, we single out the class of theories that is asymptotically free and weakly coupled in the infrared, and therefore, is amenable to semi-classical treatment. Our study is conducted by carefully identifying the vacua inside the affine Weyl chamber using Verma bases and Frobenius formula techniques. Theories with fermions in pure representations are generally strongly coupled. The only exceptions are the four-index symmetric representation of su(2) and adjoint representation of su( N c ). However, we find a plethora of admissible theories with fermions in mixed representations. A sub-class of these theories have degenerate perturbative vacua separated by domain walls. In particular, su( N c ) theories with fermions in the mixed representations adjoint⊕fundamental and adjoint⊕two-index symmetric admit degenerate vacua that spontaneously break the parity P , charge conjugation C , and time reversal T symmetries. These are the first examples of strictly weakly coupled gauge theories on R^3× S^1 with spontaneously broken C , P , and T symmetries. We also compute the fermion zero modes in the background of monopole-instantons. The monopoles and their composites (topological molecules) proliferate in the vacuum leading to the confinement of electric charges. Interestingly enough, some theories have also accidental degenerate vacua, which are not related by any symmetry. These vacua admit different numbers of fermionic zero modes, and hence, different kinds of topological molecules. The lack of symmetry, however, indicates that such degeneracy might be lifted by higher order corrections. Finally, we study the general phase structure of adjoint⊕fundamental theories in the small circle and decompactification limits.

FAST TRACK COMMUNICATION Single-charge rotating black holes in four-dimensional gauged supergravity

NASA Astrophysics Data System (ADS)

Chow, David D. K.

2011-02-01

We consider four-dimensional U(1)4 gauged supergravity, and obtain asymptotically AdS4, non-extremal, charged, rotating black holes with one non-zero U(1) charge. The thermodynamic quantities are computed. We obtain a generalization that includes a NUT parameter. The general solution has a discrete symmetry involving inversion of the rotation parameter, and has a string frame metric that admits a rank-2 Killing-Stäckel tensor.

Why PeV scale left-right symmetry is a good thing

NASA Astrophysics Data System (ADS)

Yajnik, Urjit A.

2017-10-01

Left-right symmetric gauge theory presents a minimal paradigm to accommodate massive neutrinos with all the known conserved symmetries duly gauged. The work presented here is based on the argument that the see-saw mechanism does not force the new right-handed symmetry scale to be very high, and as such some of the species from the spectrum of the new gauge and Higgs bosons can have masses within a few orders of magnitude of the TeV scale. The scale of the left-right parity breaking in turn can be sequestered from the Planck scale by supersymmetry. We have studied several formulations of such just beyond Standard Model (JBSM) theories for their consistency with cosmology. Specifically, the need to eliminate phenomenologically undesirable domain walls gives many useful clues. The possibility that the exact left-right symmetry breaks in conjunction with supersymmetry has been explored in the context of gauge mediation, placing restrictions on the available parameter space. Finally, we have also studied a left-right symmetric model in the context of metastable supersymmetric vacua and obtained constraints on the mass scale of right-handed symmetry. In all the cases studied, the mass scale of the right-handed neutrino M_R remains bounded from above, and in some of the cases the scale 10^9 GeV favourable for supersymmetric thermal leptogenesis is disallowed. On the other hand, PeV scale remains a viable option, and the results warrant a more detailed study of such models for their observability in collider and astroparticle experiments.

Which symmetry? Noether, Weyl, and conservation of electric charge

NASA Astrophysics Data System (ADS)

Brading, Katherine A.

In 1918, Emmy Noether published a (now famous) theorem establishing a general connection between continuous 'global' symmetries and conserved quantities. In fact, Noether's paper contains two theorems, and the second of these deals with 'local' symmetries; prima facie, this second theorem has nothing to do with conserved quantities. In the same year, Hermann Weyl independently made the first attempt to derive conservation of electric charge from a postulated gauge symmetry. In the light of Noether's work, it is puzzling that Weyl's argument uses local gauge symmetry. This paper explores the relationships between Weyl's work, Noether's two theorems, and the modern connection between gauge symmetry and conservation of electric charge. This includes showing that Weyl's connection is essentially an application of Noether's second theorem, with a novel twist.

Supersymmetric U(1)Y‧⊗ U(1)B-L extension of the Standard Model

NASA Astrophysics Data System (ADS)

Montero, J. C.; Pleitez, V.; Sánchez-Vega, B. L.; Rodriguez, M. C.

2017-06-01

We build a supersymmetric version with SU(3)C ⊗ SU(2)L ⊗ U(1)Y‧⊗ U(1)B-L gauge symmetry, where Y‧ is a new charge and B and L are the usual baryonic and leptonic numbers. The model has three right-handed neutrinos with identical B - L charges, and can accommodate all fermion masses at the tree level. In particular, the type I seesaw mechanism is implemented for the generation of the active neutrino masses. We obtain the mass spectra of all sectors and for the scalar one we also give the flat directions allowed by the model.

Gauge interaction as periodicity modulation

NASA Astrophysics Data System (ADS)

Dolce, Donatello

2012-06-01

The paper is devoted to a geometrical interpretation of gauge invariance in terms of the formalism of field theory in compact space-time dimensions (Dolce, 2011) [8]. In this formalism, the kinematic information of an interacting elementary particle is encoded on the relativistic geometrodynamics of the boundary of the theory through local transformations of the underlying space-time coordinates. Therefore gauge interactions are described as invariance of the theory under local deformations of the boundary. The resulting local variations of the field solution are interpreted as internal transformations. The internal symmetries of the gauge theory turn out to be related to corresponding space-time local symmetries. In the approximation of local infinitesimal isometric transformations, Maxwell's kinematics and gauge invariance are inferred directly from the variational principle. Furthermore we explicitly impose periodic conditions at the boundary of the theory as semi-classical quantization condition in order to investigate the quantum behavior of gauge interaction. In the abelian case the result is a remarkable formal correspondence with scalar QED.

Strongly coupled gauge theories: What can lattice calculations teach us?

NASA Astrophysics Data System (ADS)

Hasenfratz, A.; Brower, R. C.; Rebbi, C.; Weinberg, E.; Witzel, O.

2017-12-01

The dynamical origin of electroweak symmetry breaking is an open question with many possible theoretical explanations. Strongly coupled systems predicting the Higgs boson as a bound state of a new gauge-fermion interaction form one class of candidate models. Due to increased statistics, LHC run II will further constrain the phenomenologically viable models in the near future. In the meanwhile it is important to understand the general properties and specific features of the different competing models. In this work we discuss many-flavor gauge-fermion systems that contain both massless (light) and massive fermions. The former provide Goldstone bosons and trigger electroweak symmetry breaking, while the latter indirectly influence the infrared dynamics. Numerical results reveal that such systems can exhibit a light 0++ isosinglet scalar, well separated from the rest of the spectrum. Further, when we set the scale via the vev of electroweak symmetry breaking, we predict a 2 TeV vector resonance which could be a generic feature of SU(3) gauge theories.

The dark side of flipped trinification

NASA Astrophysics Data System (ADS)

Dong, P. V.; Huong, D. T.; Queiroz, Farinaldo S.; Valle, José W. F.; Vaquera-Araujo, C. A.

2018-04-01

We propose a model which unifies the Left-Right symmetry with the SU(3) L gauge group, called flipped trinification, and based on the SU(3) C ⊗ SU(3) L ⊗ SU(3) R ⊗ U(1) X gauge group. The model inherits the interesting features of both symmetries while elegantly explaining the origin of the matter parity, W P = (-1)3( B- L)+2 s , and dark matter stability. We develop the details of the spontaneous symmetry breaking mechanism in the model, determining the relevant mass eigenstates, and showing how neutrino masses are easily generated via the seesaw mechanism. Moreover, we introduce viable dark matter candidates, encompassing a fermion, scalar and possibly vector fields, leading to a potentially novel dark matter phenomenology.

Higgsed Gauge-flation

NASA Astrophysics Data System (ADS)

Adshead, Peter; Sfakianakis, Evangelos I.

2017-08-01

We study a variant of Gauge-flation where the gauge symmetry is spontaneously broken by a Higgs sector. We work in the Stueckelberg limit and demonstrate that the dynamics remain (catastrophically) unstable for cases where the gauge field masses satisfy γ < 2, where γ = g 2 ψ 2/ H 2, g is the gauge coupling, ψ is the gauge field vacuum expectation value, and H is the Hubble rate. We compute the spectrum of density fluctuations and gravitational waves, and show that the model can produce observationally viable spectra. The background gauge field texture violates parity, resulting in a chiral gravitational wave spectrum. This arises due to an exponential enhancement of one polarization of the spin-2 fluctuation of the gauge field. Higgsed Gauge-flation can produce observable gravitational waves at inflationary energy scales well below the GUT scale.

Dark matter from a classically scale-invariant S U (3 )X

NASA Astrophysics Data System (ADS)

Karam, Alexandros; Tamvakis, Kyriakos

2016-09-01

In this work we study a classically scale-invariant extension of the Standard Model in which the dark matter and electroweak scales are generated through the Coleman-Weinberg mechanism. The extra S U (3 )X gauge factor gets completely broken by the vacuum expectation values of two scalar triplets. Out of the eight resulting massive vector bosons the three lightest are stable due to an intrinsic Z2×Z2' discrete symmetry and can constitute dark matter candidates. We analyze the phenomenological viability of the predicted multi-Higgs sector imposing theoretical and experimental constraints. We perform a comprehensive analysis of the dark matter predictions of the model solving numerically the set of coupled Boltzmann equations involving all relevant dark matter processes and explore the direct detection prospects of the dark matter candidates.

U.S./U.S.S.R. SYMPOSIUM ON PARTICULATE CONTROL (3RD) HELD AT SUZDAL, U.S.S.R. ON SEPTEMBER 10-12, 1979

EPA Science Inventory

The proceedings document the Third U.S./U.S.S.R. Symposium on Particulate Control, September 10-12, 1979, in Suzdal, U.S.S.R. Papers covered such topics as: predicting back-corona formation and fly ash resistivity, improved electrostatic precipitator (ESP) mathematical modeling, ...

Gauge symmetry, chirality and parity effects in four-particle systems: Coulomb's law as a universal function for diatomic molecules.

PubMed

Van Hooydonk, G

2000-11-01

Following recent work in search for a universal function (Van Hooydonk, Eur. J. Inorg. Chem., (1999), 1617), we test four symmetric +/- a(n)Rn potentials for reproducing molecular potential energy curves (PECs). Classical gauge symmetry for 1/R-potentials results in generic left right asymmetric PECs. A pair of symmetric perturbed Coulomb potentials is quantitatively in accordance with observed PECs. For a bond, a four-particle system, charge inversion (a parity effect, atom chirality) is the key to explain this shape generically. A parity adapted Hamiltonian reduces from ten to two terms and to a soluble Bohr-like formula, a Kratzer (1 - Re/R)2 potential. The result is similar to the combined action of spin and wave function symmetry upon the Hamiltonian in Heitler-London theory. Analytical perturbed Coulomb functions varying with (1 - Re/R) scale attractive and repulsive branches of PECs for 13 bonds H2, HF, LiH, KH, AuH, Li2, LiF, KLi, NaCs, Rb2, RbCs, Cs2 and I2 in a single straight line. The 400 turning points for 13 bonds are reproduced with a deviation of 0.007 A at both branches. For 230 points at the repulsive side, the deviation is 0.003 A. The perturbed electrostatic Coulomb law is a universal molecular function. Ab initio zero molecular parameter functions give PECs of acceptable quality, just using atomic ionisation energies. The function can be used as a model potential for inverting levels and gives a first principle's comparison of short- and long-range interactions, important for the study of cold atoms. Wave-packet dynamics, femto-chemistry applied to the crossing of covalent and ionic curves, can provide evidence for this theory. We anticipate this scale/shape invariant scheme applies to smaller scales in nuclear and high-energy particle physics. For larger gravitational scales (Newton 1/R potentials), problems with super-unification are discussed. Reactions between hydrogen and antihydrogen, feasible in the near future, will probably produce

Exploring the supersymmetric U(1 ) B -L×U(1 ) R model with dark matter, muon g - 2 , and Z' mass limits

NASA Astrophysics Data System (ADS)

Frank, Mariana; Özdal, Özer

2018-01-01

We study the low scale predictions of the supersymmetric standard model extended by U (1 )B -L×U (1 )R symmetry, obtained from S O (10 ) breaking via a left-right supersymmetric model, imposing universal boundary conditions. Two singlet Higgs fields are responsible for the radiative U (1 )B -L×U (1 )R symmetry breaking, and a singlet fermion S is introduced to generate neutrino masses through an inverse seesaw mechanism. The lightest neutralino or sneutrino emerge as dark matter candidates, with different low scale implications. We find that the composition of the neutralino lightest supersymmetric particle (LSP) changes considerably depending on the neutralino LSP mass, from roughly half U (1 )R bino, half minimal supersymmetric model (MSSM) bino, to a singlet higgsino, or completely dominated by the MSSM higgsino. The sneutrino LSP is statistically much less likely, and when it occurs it is a 50-50 mixture of right-handed sneutrino and the scalar S ˜. Most of the solutions consistent with the relic density constraint survive the XENON 1T exclusion curve for both LSP cases. We compare the two scenarios and investigate parameter space points and find consistency with the muon anomalous magnetic moment only at the edge of a 2 σ deviation from the measured value. However, we find that the sneutrino LSP solutions could be ruled out completely by the strict reinforcement of the recent Z' mass bounds. We finally discuss collider prospects for testing the model.

A comparative assessment of R. M. Young and tipping bucket rain gauges

NASA Technical Reports Server (NTRS)

Goldhirsh, Julius; Gebo, Norman E.

1992-01-01

Rain rates as derived from standard tipping bucket rain gauges have variable integration times corresponding to the interval between bucket tips. For example, the integration time for the Weathertronics rain gauge is given by delta(T) = 15.24/R (min), where R is the rain rate expressed in mm/h and delta(T) is the time between tips expressed in minutes. It is apparent that a rain rate of 1 mm/h has an integration time in excess of 15 minutes. Rain rates larger than 15.24 mm/h will have integration times smaller than 1 minute. The integration time is dictated by the time it takes to fill a small tipping bucket where each tip gives rise to 0.254 mm of rainfall. Hence, a uniform rain rate of 1 mm/h over a 15 minute period will give rise to the same rain rate as 0 mm/h rainfall over the first 14 minutes and 15 mm/h between 14 to 15 minutes from the reference tip. Hence, the rain intensity fluctuations may not be captured with the tipping bucket rain gauge for highly variable rates encompassing lower and higher values over a given integration time. The objective of this effort is to provide an assessment of the features of the R. M. Young capacitive gauge and to compare these features with those of the standard tipping bucket rain gauge. A number of rain rate-time series derived from measurements with approximately co-located gauges are examined.

Constraining the physical state by symmetries

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fatibene, L., E-mail: lorenzo.fatibene@unito.it; INFN - Sezione Torino - IS QGSKY; Ferraris, M.

After reviewing the hole argument and its relations with initial value problem and general covariance, we shall discuss how much freedom one has to define the physical state in a generally covariant field theory (with or without internal gauge symmetries). Our analysis relies on Cauchy problems, thus it is restricted to globally hyperbolic spacetimes. We shall show that in generally covariant theories on a compact space (as well as for internal gauge symmetries on any spacetime) one has no freedom and one is forced to declare as physically equivalent two configurations which differ by a global spacetime diffeomorphism (or bymore » an internal gauge transformation) as it is usually prescribed. On the contrary, when space is not compact, the result does not hold true and one may have different options to define physically equivalent configurations, still preserving determinism. - Highlights: • Investigate the relation between the hole argument, covariance, determinism and physical state. • Show that if space is compact then any diffeomorphism is a gauge symmetry. • Show that if space is not compact then there may be more freedom in choosing gauge group.« less

Bv and Bfv Formulation of a Gauge Theory of Quadratic Lie Algebras in 2d and a Construction of W3 Topological Gravity

NASA Astrophysics Data System (ADS)

Dayi, Ömer F.

The recently proposed generalized field method for solving the master equation of Batalin and Vilkovisky is applied to a gauge theory of quadratic Lie algebras in two dimensions. The charge corresponding to BRST symmetry derived from this solution in terms of the phase space variables by using the Noether procedure, and the one found due to the BFV-method are compared and found to coincide. W3-algebra, formulated in terms of a continuous variable is exploit in the mentioned gauge theory to construct a W3 topological gravity. Moreover, its gauge fixing is briefly discussed.

Doubled lattice Chern-Simons-Yang-Mills theories with discrete gauge group

NASA Astrophysics Data System (ADS)

Caspar, S.; Mesterházy, D.; Olesen, T. Z.; Vlasii, N. D.; Wiese, U.-J.

2016-11-01

We construct doubled lattice Chern-Simons-Yang-Mills theories with discrete gauge group G in the Hamiltonian formulation. Here, these theories are considered on a square spatial lattice and the fundamental degrees of freedom are defined on pairs of links from the direct lattice and its dual, respectively. This provides a natural lattice construction for topologically-massive gauge theories, which are invariant under parity and time-reversal symmetry. After defining the building blocks of the doubled theories, paying special attention to the realization of gauge transformations on quantum states, we examine the dynamics in the group space of a single cross, which is spanned by a single link and its dual. The dynamics is governed by the single-cross electric Hamiltonian and admits a simple quantum mechanical analogy to the problem of a charged particle moving on a discrete space affected by an abstract electromagnetic potential. Such a particle might accumulate a phase shift equivalent to an Aharonov-Bohm phase, which is manifested in the doubled theory in terms of a nontrivial ground-state degeneracy on a single cross. We discuss several examples of these doubled theories with different gauge groups including the cyclic group Z(k) ⊂ U(1) , the symmetric group S3 ⊂ O(2) , the binary dihedral (or quaternion) group D¯2 ⊂ SU(2) , and the finite group Δ(27) ⊂ SU(3) . In each case the spectrum of the single-cross electric Hamiltonian is determined exactly. We examine the nature of the low-lying excited states in the full Hilbert space, and emphasize the role of the center symmetry for the confinement of charges. Whether the investigated doubled models admit a non-Abelian topological state which allows for fault-tolerant quantum computation will be addressed in a future publication.

Radiative origin of all quark and lepton masses through dark matter with flavor symmetry.

PubMed

Ma, Ernest

2014-03-07

The fundamental issue of the origin of mass for all quarks and leptons (including Majorana neutrinos) is linked to dark matter, odd under an exactly conserved Z2 symmetry which may or may not be derivable from an U(1)D gauge symmetry. The observable sector interacts with a proposed dark sector which consists of heavy neutral singlet Dirac fermions and suitably chosen new scalars. Flavor symmetry is implemented in a renormalizable context with just the one Higgs doublet (ϕ(+), ϕ(0)) of the standard model in such a way that all observed fermions obtain their masses radiatively through dark matter.

Hidden simplicity of gauge theory amplitudes

NASA Astrophysics Data System (ADS)

Drummond, J. M.

2010-11-01

These notes were given as lectures at the CERN Winter School on Supergravity, Strings and Gauge Theory 2010. We describe the structure of scattering amplitudes in gauge theories, focussing on the maximally supersymmetric theory to highlight the hidden symmetries which appear. Using the Britto, Cachzo, Feng and Witten (BCFW) recursion relations we solve the tree-level S-matrix in \\ {N}=4 super Yang-Mills theory and describe how it produces a sum of invariants of a large symmetry algebra. We review amplitudes in the planar theory beyond tree level, describing the connection between amplitudes and Wilson loops, and discuss the implications of the hidden symmetries.

Higgsed Gauge-flation

DOE PAGES

Adshead, Peter; Sfakianakis, Evangelos I.

2017-08-29

We study a variant of Gauge-flation where the gauge symmetry is spontaneously broken by a Higgs sector. Here, we work in the Stueckelberg limit and demonstrate that the dynamics remain (catastrophically) unstable for cases where the gauge field masses satisfy γ< 2, where γ= g 2 2=ψH 2, g is the gauge coupling, ψ is the gauge field vacuum expectation value, and H is the Hubble rate. We compute the spectrum of density uctuations and gravitational waves, and show that the model can produce observationally viable spectra. The background gauge field texture violates parity, resulting in a chiral gravitational wavemore » spectrum. This arises due to an exponential enhancement of one polarization of the spin-2 fluctuation of the gauge field. Higgsed Gauge-flation can produce observable gravitational waves at in inflationary energy scales well below the GUT scale.« less

Higgsed Gauge-flation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Adshead, Peter; Sfakianakis, Evangelos I.

We study a variant of Gauge-flation where the gauge symmetry is spontaneously broken by a Higgs sector. Here, we work in the Stueckelberg limit and demonstrate that the dynamics remain (catastrophically) unstable for cases where the gauge field masses satisfy γ< 2, where γ= g 2 2=ψH 2, g is the gauge coupling, ψ is the gauge field vacuum expectation value, and H is the Hubble rate. We compute the spectrum of density uctuations and gravitational waves, and show that the model can produce observationally viable spectra. The background gauge field texture violates parity, resulting in a chiral gravitational wavemore » spectrum. This arises due to an exponential enhancement of one polarization of the spin-2 fluctuation of the gauge field. Higgsed Gauge-flation can produce observable gravitational waves at in inflationary energy scales well below the GUT scale.« less

Non-Abelian Gauge Theory in the Lorentz Violating Background

NASA Astrophysics Data System (ADS)

Ganai, Prince A.; Shah, Mushtaq B.; Syed, Masood; Ahmad, Owais

2018-03-01

In this paper, we will discuss a simple non-Abelian gauge theory in the broken Lorentz spacetime background. We will study the partial breaking of Lorentz symmetry down to its sub-group. We will use the formalism of very special relativity for analysing this non-Abelian gauge theory. Moreover, we will discuss the quantisation of this theory using the BRST symmetry. Also, we will analyse this theory in the maximal Abelian gauge.

Axion predictions in SO(10) × U(1)PQ models

NASA Astrophysics Data System (ADS)

Ernst, Anne; Ringwald, Andreas; Tamarit, Carlos

2018-02-01

Non-supersymmetric Grand Unified SO(10) × U(1)PQ models have all the ingredients to solve several fundamental problems of particle physics and cosmology — neutrino masses and mixing, baryogenesis, the non-observation of strong CP violation, dark matter, inflation — in one stroke. The axion — the pseudo Nambu-Goldstone boson arising from the spontaneous breaking of the U(1)PQ Peccei-Quinn symmetry — is the prime dark matter candidate in this setup. We determine the axion mass and the low energy couplings of the axion to the Standard Model particles, in terms of the relevant gauge symmetry breaking scales. We work out the constraints imposed on the latter by gauge coupling unification. We discuss the cosmological and phenomenological implications.

Cartan gravity, matter fields, and the gauge principle

NASA Astrophysics Data System (ADS)

Westman, Hans F.; Zlosnik, Tom G.

2013-07-01

Gravity is commonly thought of as one of the four force fields in nature. However, in standard formulations its mathematical structure is rather different from the Yang-Mills fields of particle physics that govern the electromagnetic, weak, and strong interactions. This paper explores this dissonance with particular focus on how gravity couples to matter from the perspective of the Cartan-geometric formulation of gravity. There the gravitational field is represented by a pair of variables: (1) a 'contact vector' VA which is geometrically visualized as the contact point between the spacetime manifold and a model spacetime being 'rolled' on top of it, and (2) a gauge connection AμAB, here taken to be valued in the Lie algebra of SO(2,3) or SO(1,4), which mathematically determines how much the model spacetime is rotated when rolled. By insisting on two principles, the gauge principle and polynomial simplicity, we shall show how one can reformulate matter field actions in a way that is harmonious with Cartan's geometric construction. This yields a formulation of all matter fields in terms of first order partial differential equations. We show in detail how the standard second order formulation can be recovered. In particular, the Hodge dual, which characterizes the structure of bosonic field equations, pops up automatically. Furthermore, the energy-momentum and spin-density three-forms are naturally combined into a single object here denoted the spin-energy-momentum three-form. Finally, we highlight a peculiarity in the mathematical structure of our first-order formulation of Yang-Mills fields. This suggests a way to unify a U(1) gauge field with gravity into a SO(1,5)-valued gauge field using a natural generalization of Cartan geometry in which the larger symmetry group is spontaneously broken down to SO(1,3)×U(1). The coupling of this unified theory to matter fields and possible extensions to non-Abelian gauge fields are left as open questions.

Cartan gravity, matter fields, and the gauge principle

DOE Office of Scientific and Technical Information (OSTI.GOV)

Westman, Hans F., E-mail: hwestman74@gmail.com; Zlosnik, Tom G., E-mail: t.zlosnik@imperial.ac.uk

Gravity is commonly thought of as one of the four force fields in nature. However, in standard formulations its mathematical structure is rather different from the Yang–Mills fields of particle physics that govern the electromagnetic, weak, and strong interactions. This paper explores this dissonance with particular focus on how gravity couples to matter from the perspective of the Cartan-geometric formulation of gravity. There the gravitational field is represented by a pair of variables: (1) a ‘contact vector’ V{sup A} which is geometrically visualized as the contact point between the spacetime manifold and a model spacetime being ‘rolled’ on top ofmore » it, and (2) a gauge connection A{sub μ}{sup AB}, here taken to be valued in the Lie algebra of SO(2,3) or SO(1,4), which mathematically determines how much the model spacetime is rotated when rolled. By insisting on two principles, the gauge principle and polynomial simplicity, we shall show how one can reformulate matter field actions in a way that is harmonious with Cartan’s geometric construction. This yields a formulation of all matter fields in terms of first order partial differential equations. We show in detail how the standard second order formulation can be recovered. In particular, the Hodge dual, which characterizes the structure of bosonic field equations, pops up automatically. Furthermore, the energy–momentum and spin-density three-forms are naturally combined into a single object here denoted the spin-energy–momentum three-form. Finally, we highlight a peculiarity in the mathematical structure of our first-order formulation of Yang–Mills fields. This suggests a way to unify a U(1) gauge field with gravity into a SO(1,5)-valued gauge field using a natural generalization of Cartan geometry in which the larger symmetry group is spontaneously broken down to SO(1,3)×U(1). The coupling of this unified theory to matter fields and possible extensions to non-Abelian gauge fields are

Higgs boson from an extended symmetry

DOE Office of Scientific and Technical Information (OSTI.GOV)

Barbieri, Riccardo; Bellazzini, Brando; Rychkov, Vyacheslav S.

The variety of ideas put forward in the context of a composite picture for the Higgs boson calls for a simple and effective description of the related phenomenology. Such a description is given here by means of a minimal model and is explicitly applied to the example of a Higgs-top sector from an SO(5) symmetry. We discuss the spectrum, the electroweak precision tests, B-physics, and naturalness. We show the difficulty in complying with the different constraints. The extended gauge sector relative to the standard SU(2)xU(1), if there is any, has little or no impact on these considerations. We also discussmore » the relation of the minimal model with its 'little Higgs' or holographic extensions based on the same symmetry.« less

On 3-gauge transformations, 3-curvatures, and Gray-categories

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, Wei, E-mail: wwang@zju.edu.cn

In the 3-gauge theory, a 3-connection is given by a 1-form A valued in the Lie algebra g, a 2-form B valued in the Lie algebra h, and a 3-form C valued in the Lie algebra l, where (g,h,l) constitutes a differential 2-crossed module. We give the 3-gauge transformations from one 3-connection to another, and show the transformation formulae of the 1-curvature 2-form, the 2-curvature 3-form, and the 3-curvature 4-form. The gauge configurations can be interpreted as smooth Gray-functors between two Gray 3-groupoids: the path 3-groupoid P{sub 3}(X) and the 3-gauge group G{sup L} associated to the 2-crossed module L,more » whose differential is (g,h,l). The derivatives of Gray-functors are 3-connections, and the derivatives of lax-natural transformations between two such Gray-functors are 3-gauge transformations. We give the 3-dimensional holonomy, the lattice version of the 3-curvature, whose derivative gives the 3-curvature 4-form. The covariance of 3-curvatures easily follows from this construction. This Gray-categorical construction explains why 3-gauge transformations and 3-curvatures have the given forms. The interchanging 3-arrows are responsible for the appearance of terms with the Peiffer commutator (, )« less

Right-handed neutrino dark matter in a U(1) extension of the Standard Model

NASA Astrophysics Data System (ADS)

Cox, Peter; Han, Chengcheng; Yanagida, Tsutomu T.

2018-01-01

We consider minimal U(1) extensions of the Standard Model in which one of the right-handed neutrinos is charged under the new gauge symmetry and plays the role of dark matter. In particular, we perform a detailed phenomenological study for the case of a U(1)(B‑L)3 flavoured B‑L symmetry. If perturbativity is required up to high-scales, we find an upper bound on the dark matter mass of mχlesssim2 TeV, significantly stronger than that obtained in simplified models. Furthermore, if the U(1)(B‑L)3 breaking scalar has significant mixing with the SM Higgs, there are already strong constraints from direct detection. On the other hand, there remains significant viable parameter space in the case of small mixing, which may be probed in the future via LHC Z' searches and indirect detection. We also comment on more general anomaly-free symmetries consistent with a TeV-scale RH neutrino dark matter candidate, and show that if two heavy RH neutrinos for leptogenesis are also required, one is naturally led to a single-parameter class of U(1) symmetries.

Analytic derivation of an approximate SU(3) symmetry inside the symmetry triangle of the interacting boson approximation model

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bonatsos, Dennis; Karampagia, S.; Casten, R. F.

2011-05-15

Using a contraction of the SU(3) algebra to the algebra of the rigid rotator in the large-boson-number limit of the interacting boson approximation (IBA) model, a line is found inside the symmetry triangle of the IBA, along which the SU(3) symmetry is preserved. The line extends from the SU(3) vertex to near the critical line of the first-order shape/phase transition separating the spherical and prolate deformed phases, and it lies within the Alhassid-Whelan arc of regularity, the unique valley of regularity connecting the SU(3) and U(5) vertices in the midst of chaotic regions. In addition to providing an explanation formore » the existence of the arc of regularity, the present line represents an example of an analytically determined approximate symmetry in the interior of the symmetry triangle of the IBA. The method is applicable to algebraic models possessing subalgebras amenable to contraction. This condition is equivalent to algebras in which the equilibrium ground state and its rotational band become energetically isolated from intrinsic excitations, as typified by deformed solutions to the IBA for large numbers of valence nucleons.« less

Gauging away a big bang

NASA Astrophysics Data System (ADS)

Krishnan, Chethan; Raju, Avinash

2017-08-01

We argue that in the tensionless phase of string theory where the stringy gauge symmetries are unbroken, (at least some) cosmological singularities can be understood as gauge artefacts. We present two conceptually related, but distinct, pieces of evidence: one relying on spacetime and the other on worldsheet.

Gauge and Non-Gauge Tensor Multiplets in 5D Conformal Supergravity

NASA Astrophysics Data System (ADS)

Kugo, T.; Ohashi, K.

2002-12-01

An off-shell formulation of two distinct tensor multiplets, a massive tensor multiplet and a tensor gauge multiplet, is presented in superconformal tensor calculus in five-dimensional space-time. Both contain a rank 2 antisymmetric tensor field, but there is no gauge symmetry in the former, while it is a gauge field in the latter. Both multiplets have 4 bosonic and 4 fermionic on-shell modes, but the former consists of 16 (boson)+16 (fermion) component fields, while the latter consists of 8 (boson)+8 (fermion) component fields.

Manganese-induced magnetic symmetry breaking and its correlation with the metal-insulator transition in bilayered S r3(Ru1-xM nx) 2O7

NASA Astrophysics Data System (ADS)

Zhang, Qiang; Ye, Feng; Tian, Wei; Cao, Huibo; Chi, Songxue; Hu, Biao; Diao, Zhenyu; Tennant, David A.; Jin, Rongying; Zhang, Jiandi; Plummer, Ward

2017-06-01

Bilayered S r3R u2O7 is an unusual metamagnetic metal with inherently antiferromagnetic (AFM) and ferromagnetic (FM) fluctuations. Partial substitution of Ru by Mn results in the establishment of a metal-insulator transition (MIT) at TMIT and AFM ordering at TM in S r3(Ru1-xM nx) 2O7 . Using elastic neutron scattering, we investigated the effect of Mn doping on the magnetic structure, in-plane magnetic correlation lengths and their correlation to the MIT in S r3(Ru1-xM nx) 2O7 (x =0.06 and 0.12). With the increase of Mn doping (x ) from 0.06 to 0.12 or the decrease of temperatures for x =0.12 , an evolution from an in-plane short-range to long-range antiferromagnetic (AFM) ground state occurs. For both compounds, the magnetic ordering has a double-stripe configuration, and the onset of magnetic correlation with an anisotropic behavior coincides with the sharp rise in electrical resistivity and specific heat. Since it does not induce a measurable lattice distortion, the double-stripe antiferromagnetic order with anisotropic spin texture breaks symmetry from a C4 v crystal lattice to a C2 v magnetic sublattice. These observations shed light on an age-old question regarding the Slater versus Mott-type MIT.

Observation of g/u-symmetry mixing in the high-n Rydberg states of HD

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sprecher, Daniel; Merkt, Frédéric, E-mail: frederic.merkt@phys.chem.ethz.ch

2014-03-28

The structure and dynamics of high-n Rydberg states belonging to series converging to the (v{sup +} = 0, N{sup +} = 0–2) levels of the X{sup +2}Σ{sub g}{sup +} electronic ground state of HD{sup +} were studied by high-resolution spectroscopy from the GK{sup 1}Σ{sub g}{sup +} (v= 1, N = 1) state under field-free conditions. Three effects of g/u-symmetry breaking were detected: (i) Single-photon transitions from the GK (v = 1, N = 1) state of gerade symmetry to the 30d2{sub 1} and 31g2{sub 2} Rydberg states of gerade symmetry were observed after careful compensation of the stray electric fields. (ii)more » The singlet 61p1{sub 2} Rydberg state of ungerade symmetry was found to autoionize to the N{sup +} = 0, ℓ = 2 ionization continuum of gerade symmetry with a lifetime of 77(10) ns. (iii) Shifts of up to 20 MHz induced by g/u-symmetry mixing were measured for members of the np1{sub 1} Rydberg series which lie close to nd2{sub 1} Rydberg states. These observations were analyzed in the framework of multichannel quantum-defect theory. From the observed level shifts, the off-diagonal eigenquantum-defect element μ{sub pd} of singlet-π symmetry was determined to be 0.0023(3) and the corresponding autoionization dynamics could be characterized. The ionization energy of the GK (v = 1, N = 1) state of HD was determined to be 12 710.544 23(10) cm{sup −1}.« less

Classification of robust heteroclinic cycles for vector fields in {\\protect\\bb R}^3 with symmetry

NASA Astrophysics Data System (ADS)

Hawker, David; Ashwin, Peter

2005-09-01

We consider a classification of robust heteroclinic cycles in the positive octant of {\\bb R}^3 under the action of the symmetry group {{\\bb Z}_2}^3 . We introduce a coding system to represent different classes up to a topological equivalence, and produce a characterization of all types of robust heteroclinic cycle that can arise in this situation. These cycles may or may not contain the origin within the cycle. We proceed to find a connection between our problem and meandric numbers. We find a direct correlation between the number of classes of robust heteroclinic cycle that do not include the origin and the 'Mercedes-Benz' sequence of integers characterizing meanders through a 'Y-shaped' configuration. We investigate upper and lower bounds for the number of classes possible for robust cycles between n equilibria, one of which may be the origin.

Right-handed neutrino dark matter in the classically conformal U(1 ) ' extended standard model

NASA Astrophysics Data System (ADS)

Oda, Satsuki; Okada, Nobuchika; Takahashi, Dai-suke

2017-11-01

We consider the dark matter (DM) scenario in the context of the classically conformal U(1 ) ' extended standard model (SM), with three right-handed neutrinos (RHNs) and the U(1 ) ' Higgs field. The model is free from all of the U(1 ) ' gauge and gravitational anomalies in the presence of the three RHNs. We introduce a Z2 parity in the model, under which an odd parity is assigned to one RHN, while all of the other particles are assigned to be Z2 even, and hence the Z2-odd RHN serves as a DM candidate. In this model, the U(1 ) ' gauge symmetry is radiatively broken through the Coleman-Weinberg mechanism, by which the electroweak symmetry breaking is triggered. There are three free parameters in our model—the U(1 ) ' charge of the SM Higgs doublet (xH ), the new U(1 ) ' gauge coupling (gX ), and the U(1 ) ' gauge boson (Z') mass (mZ')—which are severely constrained in order to solve the electroweak vacuum instability problem, and satisfy the LHC Run-2 bounds from the search for the Z' boson resonance. In addition to these constraints, we investigate the RHN DM physics. Because of the nature of classical conformality, we find that a RHN DM pair mainly annihilates into the SM particles through Z' boson exchange. This is the so-called Z'-portal DM scenario. Combining the electroweak vacuum stability condition, the LHC Run-2 bounds, and the cosmological constraint from the observed DM relic density, we find that all constraints work together to narrow the allowed parameter regions and, in particular, exclude mZ'≲3.5 TeV . For the obtained allowed regions, we calculate the spin-independent cross section of the RHN DM with nucleons. We find that the resultant cross section is well below the current experimental upper bounds.

Explaining the DAMPE data with scalar dark matter and gauged U(1)_{L_e-L_μ } interaction

NASA Astrophysics Data System (ADS)

Cao, Junjie; Feng, Lei; Guo, Xiaofei; Shang, Liangliang; Wang, Fei; Wu, Peiwen; Zu, Lei

2018-03-01

Inspired by the peak structure observed by recent DAMPE experiment in e^+e^- cosmic-ray spectrum, we consider a scalar dark matter (DM) model with gauged U(1)_{L_e-L_μ } symmetry, which is the most economical anomaly-free theory to potentially explain the peak by DM annihilation in nearby subhalo. We utilize the process χ χ → Z^' Z^' → l \\bar{l} l^' \\bar{l}^' , where χ , Z^' , l^{(' )} denote the scalar DM, the new gauge boson and l^{(' )} =e, μ , respectively, to generate the e^+e^- spectrum. By fitting the predicted spectrum to the experimental data, we obtain the favored DM mass range m_χ ˜eq 3060^{+80}_{-100} GeV and Δ m ≡ m_χ - m_{Z^' } ≲ 14 GeV at 68% Confidence Level (C.L.). Furthermore, we determine the parameter space of the model which can explain the peak and meanwhile satisfy the constraints from DM relic abundance, DM direct detection and the collider bounds. We conclude that the model we consider can account for the peak, although there exists a tension with the constraints from the LEP-II bound on m_{Z^' } arising from the cross section measurement of e^+e^- → Z^' *} → e^+ e^-.

Inflection-point inflation in a hyper-charge oriented U ( 1 ) X model

DOE PAGES

Okada, Nobuchika; Okada, Satomi; Raut, Digesh

2017-03-31

Inflection-point inflation is an interesting possibility to realize a successful slow-roll inflation when inflation is driven by a single scalar field with its value during inflation below the Planck mass (ΦI≲M Pl). In order for a renormalization group (RG) improved effective λΦ 4 potential to develop an inflection-point, the running quartic coupling λ(Φ) must exhibit a minimum with an almost vanishing value in its RG evolution, namely λ(Φ I)≃0 and β λ(ΦI)≃0, where β λ is the beta-function of the quartic coupling. Here in this paper, we consider the inflection-point inflation in the context of the minimal gauged U(1) Xmore » extended Standard Model (SM), which is a generalization of the minimal U(1) B$-$L model, and is constructed as a linear combination of the SM U(1) Y and U(1) B$-$L gauge symmetries. We identify the U(1) X Higgs field with the inflaton field. For a successful inflection-point inflation to be consistent with the current cosmological observations, the mass ratios among the U(1) X gauge boson, the right-handed neutrinos and the U(1) X Higgs boson are fixed. Focusing on the case that the extra U(1) X gauge symmetry is mostly aligned along the SM U(1) Y direction, we investigate a consistency between the inflationary predictions and the latest LHC Run-2 results on the search for a narrow resonance with the di-lepton final state.« less

Inflection-point inflation in a hyper-charge oriented U ( 1 ) X model

DOE Office of Scientific and Technical Information (OSTI.GOV)

Okada, Nobuchika; Okada, Satomi; Raut, Digesh

Inflection-point inflation is an interesting possibility to realize a successful slow-roll inflation when inflation is driven by a single scalar field with its value during inflation below the Planck mass (ΦI≲M Pl). In order for a renormalization group (RG) improved effective λΦ 4 potential to develop an inflection-point, the running quartic coupling λ(Φ) must exhibit a minimum with an almost vanishing value in its RG evolution, namely λ(Φ I)≃0 and β λ(ΦI)≃0, where β λ is the beta-function of the quartic coupling. Here in this paper, we consider the inflection-point inflation in the context of the minimal gauged U(1) Xmore » extended Standard Model (SM), which is a generalization of the minimal U(1) B$-$L model, and is constructed as a linear combination of the SM U(1) Y and U(1) B$-$L gauge symmetries. We identify the U(1) X Higgs field with the inflaton field. For a successful inflection-point inflation to be consistent with the current cosmological observations, the mass ratios among the U(1) X gauge boson, the right-handed neutrinos and the U(1) X Higgs boson are fixed. Focusing on the case that the extra U(1) X gauge symmetry is mostly aligned along the SM U(1) Y direction, we investigate a consistency between the inflationary predictions and the latest LHC Run-2 results on the search for a narrow resonance with the di-lepton final state.« less

Atomic quantum simulation of dynamical gauge fields coupled to fermionic matter: from string breaking to evolution after a quench.

PubMed

Banerjee, D; Dalmonte, M; Müller, M; Rico, E; Stebler, P; Wiese, U-J; Zoller, P

2012-10-26

Using a Fermi-Bose mixture of ultracold atoms in an optical lattice, we construct a quantum simulator for a U(1) gauge theory coupled to fermionic matter. The construction is based on quantum links which realize continuous gauge symmetry with discrete quantum variables. At low energies, quantum link models with staggered fermions emerge from a Hubbard-type model which can be quantum simulated. This allows us to investigate string breaking as well as the real-time evolution after a quench in gauge theories, which are inaccessible to classical simulation methods.

Natural electroweak breaking from a mirror symmetry.

PubMed

Chacko, Z; Goh, Hock-Seng; Harnik, Roni

2006-06-16

We present "twin Higgs models," simple realizations of the Higgs boson as a pseudo Goldstone boson that protect the weak scale from radiative corrections up to scales of order 5-10 TeV. In the ultraviolet these theories have a discrete symmetry which interchanges each standard model particle with a corresponding particle which transforms under a twin or a mirror standard model gauge group. In addition, the Higgs sector respects an approximate global symmetry. When this global symmetry is broken, the discrete symmetry tightly constrains the form of corrections to the pseudo Goldstone Higgs potential, allowing natural electroweak symmetry breaking. Precision electroweak constraints are satisfied by construction. These models demonstrate that, contrary to the conventional wisdom, stabilizing the weak scale does not require new light particles charged under the standard model gauge groups.

Generalization of Friedberg-Lee symmetry

DOE Office of Scientific and Technical Information (OSTI.GOV)

Huang Chaoshang; Li Tianjun; George P. and Cynthia W. Mitchell Institute for Fundamental Physics, Texas A and M University, College Station, Texas 77843

2008-07-01

We study the possible origin of Friedberg-Lee symmetry. First, we propose the generalized Friedberg-Lee symmetry in the potential by including the scalar fields in the field transformations, which can be broken down to the Friedberg-Lee symmetry spontaneously. We show that the generalized Friedberg-Lee symmetry allows a typical form of Yukawa couplings, and the realistic neutrino masses and mixings can be generated via the seesaw mechanism. If the right-handed neutrinos transform nontrivially under the generalized Friedberg-Lee symmetry, we can have the testable TeV scale seesaw mechanism. Second, we present two models with the SO(3)xU(1) global flavor symmetry in the lepton sector.more » After the flavor symmetry breaking, we can obtain the charged lepton masses, and explain the neutrino masses and mixings via the seesaw mechanism. Interestingly, the complete neutrino mass matrices are similar to those of the above models with generalized Friedberg-Lee symmetry. So the Friedberg-Lee symmetry is the residual symmetry in the neutrino mass matrix after the SO(3)xU(1) flavor symmetry breaking.« less

Hidden local symmetry and beyond

NASA Astrophysics Data System (ADS)

Yamawaki, Koichi

Gerry Brown was a godfather of our hidden local symmetry (HLS) for the vector meson from the birth of the theory throughout his life. The HLS is originated from very nature of the nonlinear realization of the symmetry G based on the manifold G/H, and thus is universal to any physics based on the nonlinear realization. Here, I focus on the Higgs Lagrangian of the Standard Model (SM), which is shown to be equivalent to the nonlinear sigma model based on G/H = SU(2)L ×SU(2)R/SU(2)V with additional symmetry, the nonlinearly-realized scale symmetry. Then, the SM does have a dynamical gauge boson of the SU(2)V HLS, “SM ρ meson”, in addition to the Higgs as a pseudo-dilaton as well as the NG bosons to be absorbed in to the W and Z. Based on the recent work done with Matsuzaki and Ohki, I discuss a novel possibility that the SM ρ meson acquires kinetic term by the SM dynamics itself, which then stabilizes the skyrmion dormant in the SM as a viable candidate for the dark matter, what we call “dark SM skyrmion (DSMS)”.

Symmetry-protected gapless Z2 spin liquids

NASA Astrophysics Data System (ADS)

Lu, Yuan-Ming

2018-03-01

Despite rapid progress in understanding gapped topological states, much less is known about gapless topological phases of matter, especially in strongly correlated electrons. In this work, we discuss a large class of robust gapless quantum spin liquids in frustrated magnets made of half-integer spins, which are described by gapless fermionic spinons coupled to dynamical Z2 gauge fields. Requiring U(1 ) spin conservation, time-reversal, and certain space-group symmetries, we show that certain spinon symmetry fractionalization class necessarily leads to a gapless spectrum. These gapless excitations are stable against any perturbations, as long as the required symmetries are preserved. Applying these gapless criteria to spin-1/2 systems on square, triangular, and kagome lattices, we show that all gapped symmetric Z2 spin liquids in Abrikosov-fermion representation can also be realized in Schwinger-boson representation. This leads to 64 gapped Z2 spin liquids on square lattice, and 8 gapped states on both kagome and triangular lattices.

Accurate measurement of heteronuclear dipolar couplings by phase-alternating R-symmetry (PARS) sequences in magic angle spinning NMR spectroscopy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hou, Guangjin, E-mail: hou@udel.edu, E-mail: tpolenov@udel.edu; Lu, Xingyu, E-mail: luxingyu@udel.edu, E-mail: lexvega@comcast.net; Vega, Alexander J., E-mail: luxingyu@udel.edu, E-mail: lexvega@comcast.net

2014-09-14

We report a Phase-Alternating R-Symmetry (PARS) dipolar recoupling scheme for accurate measurement of heteronuclear {sup 1}H-X (X = {sup 13}C, {sup 15}N, {sup 31}P, etc.) dipolar couplings in MAS NMR experiments. It is an improvement of conventional C- and R-symmetry type DIPSHIFT experiments where, in addition to the dipolar interaction, the {sup 1}H CSA interaction persists and thereby introduces considerable errors in the dipolar measurements. In PARS, phase-shifted RN symmetry pulse blocks applied on the {sup 1}H spins combined with π pulses applied on the X spins at the end of each RN block efficiently suppress the effect from {supmore » 1}H chemical shift anisotropy, while keeping the {sup 1}H-X dipolar couplings intact. Another advantage over conventional DIPSHIFT experiments, which require the signal to be detected in the form of a reduced-intensity Hahn echo, is that the series of π pulses refocuses the X chemical shift and avoids the necessity of echo formation. PARS permits determination of accurate dipolar couplings in a single experiment; it is suitable for a wide range of MAS conditions including both slow and fast MAS frequencies; and it assures dipolar truncation from the remote protons. The performance of PARS is tested on two model systems, [{sup 15}N]-N-acetyl-valine and [U-{sup 13}C,{sup 15}N]-N-formyl-Met-Leu-Phe tripeptide. The application of PARS for site-resolved measurement of accurate {sup 1}H-{sup 15}N dipolar couplings in the context of 3D experiments is presented on U-{sup 13}C,{sup 15}N-enriched dynein light chain protein LC8.« less

Massless spectra and gauge couplings at one-loop on non-factorisable toroidal orientifolds

NASA Astrophysics Data System (ADS)

Berasaluce-González, Mikel; Honecker, Gabriele; Seifert, Alexander

2018-01-01

So-called 'non-factorisable' toroidal orbifolds can be rewritten in a factorised form as a product of three two-tori by imposing an additional shift symmetry. This finding of Blaszczyk et al. [1] provides a new avenue to Conformal Field Theory methods, by which the vector-like massless matter spectrum - and thereby the type of gauge group enhancement on orientifold invariant fractional D6-branes - and the one-loop corrections to the gauge couplings in Type IIA orientifold theories can be computed in addition to the well-established chiral matter spectrum derived from topological intersection numbers among three-cycles. We demonstrate this framework for the Z4 × ΩR orientifolds on the A3 ×A1 ×B2-type torus. As observed before for factorisable backgrounds, also here the one-loop correction can drive the gauge groups to stronger coupling as demonstrated by means of a four-generation Pati-Salam example.

Base Pairing between U3 Small Nucleolar RNA and the 5′ End of 18S rRNA Is Required for Pre-rRNA Processing

PubMed Central

Sharma, Kishor; Tollervey, David

1999-01-01

The loop of a stem structure close to the 5′ end of the 18S rRNA is complementary to the box A region of the U3 small nucleolar RNA (snoRNA). Substitution of the 18S loop nucleotides inhibited pre-rRNA cleavage at site A1, the 5′ end of the 18S rRNA, and at site A2, located 1.9 kb away in internal transcribed spacer 1. This inhibition was largely suppressed by a compensatory mutation in U3, demonstrating functional base pairing. The U3–pre-rRNA base pairing is incompatible with the structure that forms in the mature 18S rRNA and may prevent premature folding of the pre-rRNA. In the Escherichia coli pre-rRNA the homologous region of the 16S rRNA is also sequestered, in that case by base pairing to the 5′ external transcribed spacer (5′ ETS). Cleavage at site A0 in the yeast 5′ ETS strictly requires base pairing between U3 and a sequence within the 5′ ETS. In contrast, the U3-18S interaction is not required for A0 cleavage. U3 therefore carries out at least two functionally distinct base pair interactions with the pre-rRNA. The nucleotide at the site of A1 cleavage was shown to be specified by two distinct signals; one of these is the stem-loop structure within the 18S rRNA. However, in contrast to the efficiency of cleavage, the position of A1 cleavage is not dependent on the U3-loop interaction. We conclude that the 18S stem-loop structure is recognized at least twice during pre-rRNA processing. PMID:10454548

Multi-component fermionic dark matter and IceCube PeV scale neutrinos in left-right model with gauge unification

NASA Astrophysics Data System (ADS)

Borah, Debasish; Dasgupta, Arnab; Dey, Ujjal Kumar; Patra, Sudhanwa; Tomar, Gaurav

2017-09-01

We consider a simple extension of the minimal left-right symmetric model (LRSM) in order to explain the PeV neutrino events seen at the IceCube experiment from a heavy decaying dark matter. The dark matter sector is composed of two fermions: one at PeV scale and the other at TeV scale such that the heavier one can decay into the lighter one and two neutrinos. The gauge annihilation cross sections of PeV dark matter are not large enough to generate its relic abundance within the observed limit. We include a pair of real scalar triplets Ω L,R which can bring the thermally overproduced PeV dark matter abundance into the observed range through late time decay and consequent entropy release thereby providing a consistent way to obtain the correct relic abundance without violating the unitarity bound on dark matter mass. Another scalar field, a bitriplet under left-right gauge group is added to assist the heavier dark matter decay. The presence of an approximate global U(1) X symmetry can naturally explain the origin of tiny couplings required for long-lived nature of these decaying particles. We also show, how such an extended LRSM can be incorporated within a non-supersymmetric SO(10) model where the gauge coupling unification at a very high scale naturally accommodate a PeV scale intermediate symmetry, required to explain the PeV events at IceCube.

Antisymplectic gauge theories

NASA Astrophysics Data System (ADS)

Batalin, Igor; Marnelius, Robert

1998-02-01

A general field-antifield BV formalism for antisymplectic first class constraints is proposed. It is as general as the corresponding symplectic BFV-BRST formulation and it is demonstrated to be consistent with a previously proposed formalism for antisymplectic second class constraints through a generalized conversion to corresponding first class constraints. Thereby the basic concept of gauge symmetry is extended to apply to quite a new class of gauge theories potentially possible to exist.

Local gauge symmetry on optical lattices?

DOE Office of Scientific and Technical Information (OSTI.GOV)

Liu, Yuzhi; Meurice, Yannick; Tsai, Shan-Wen

2012-11-01

The versatile technology of cold atoms confined in optical lattices allows the creation of a vast number of lattice geometries and interactions, providing a promising platform for emulating various lattice models. This opens the possibility of letting nature take care of sign problems and real time evolution in carefully prepared situations. Up to now, experimentalists have succeeded to implement several types of Hubbard models considered by condensed matter theorists. In this proceeding, we discuss the possibility of extending this effort to lattice gauge theory. We report recent efforts to establish the strong coupling equivalence between the Fermi Hubbard model andmore » SU(2) pure gauge theory in 2+1 dimensions by standard determinantal methods developed by Robert Sugar and collaborators. We discuss the possibility of using dipolar molecules and external fields to build models where the equivalence holds beyond the leading order in the strong coupling expansion.« less

Origin of the U(1) field mass in superconductors

NASA Astrophysics Data System (ADS)

Koizumi, Hiroyasu

2017-05-01

Recently, a new theory for superconductivity has been put forward, in which the persistent current generation is attributed to the emergent singularities of the electronic wave function that are created by the spin-twisting itinerant circular motion of electrons. The persistent current generated by this mechanism behaves in every respect like supercurrent in superconductors, yielding the flux quantum h/2e and the Josephson frequency 2eV/h, where h is Planck’s constant, -e is the electron charge, and V is the voltage across the Josephson junction. The mass generation of the U(1) gauge field (or the Meissner effect) in the new theory is due to the emergence of topological objects, ‘instantons’ generated by the single-valued requirement of the wave function in the presence of the emergent singularities. The current standard theory of superconductivity is based on the BCS theory, and explains the emergence of superconductivity as due to the global U(1) gauge symmetry breaking realized by the Cooper pair formation. The U(1) field mass generation is believed to be due to this global U(1) gauge symmetry breaking. However, the feasibility of this mechanism has been questioned since no known interaction can prepare the global U(1) symmetry broken state from the normal state. We argue here that the U(1) mass generation in the BCS superconductor can be attributed to the one by the instanton mentioned above if the Rashba spin-orbit interaction is added. Then, the occurrence of persistent current generation becomes due to the instanton formation, and the role of the Cooper pair formation is to stabilize the instanton by providing an energy gap for perturbative excitations. Upon forming the Cooper pair, the instanton is stabilized and persistent current generation becomes possible. Thus, the superconducting transition temperature coincides with the Cooper pair formation temperature.

U(1) Wilson lattice gauge theories in digital quantum simulators

NASA Astrophysics Data System (ADS)

Muschik, Christine; Heyl, Markus; Martinez, Esteban; Monz, Thomas; Schindler, Philipp; Vogell, Berit; Dalmonte, Marcello; Hauke, Philipp; Blatt, Rainer; Zoller, Peter

2017-10-01

Lattice gauge theories describe fundamental phenomena in nature, but calculating their real-time dynamics on classical computers is notoriously difficult. In a recent publication (Martinez et al 2016 Nature 534 516), we proposed and experimentally demonstrated a digital quantum simulation of the paradigmatic Schwinger model, a U(1)-Wilson lattice gauge theory describing the interplay between fermionic matter and gauge bosons. Here, we provide a detailed theoretical analysis of the performance and the potential of this protocol. Our strategy is based on analytically integrating out the gauge bosons, which preserves exact gauge invariance but results in complicated long-range interactions between the matter fields. Trapped-ion platforms are naturally suited to implementing these interactions, allowing for an efficient quantum simulation of the model, with a number of gate operations that scales polynomially with system size. Employing numerical simulations, we illustrate that relevant phenomena can be observed in larger experimental systems, using as an example the production of particle-antiparticle pairs after a quantum quench. We investigate theoretically the robustness of the scheme towards generic error sources, and show that near-future experiments can reach regimes where finite-size effects are insignificant. We also discuss the challenges in quantum simulating the continuum limit of the theory. Using our scheme, fundamental phenomena of lattice gauge theories can be probed using a broad set of experimentally accessible observables, including the entanglement entropy and the vacuum persistence amplitude.

Deformations, moduli stabilisation and gauge couplings at one-loop

NASA Astrophysics Data System (ADS)

Honecker, Gabriele; Koltermann, Isabel; Staessens, Wieland

2017-04-01

We investigate deformations of Z_2 orbifold singularities on the toroidal orbifold {T}^6/(Z_2× Z_6) with discrete torsion in the framework of Type IIA orientifold model building with intersecting D6-branes wrapping special Lagrangian cycles. To this aim, we employ the hypersurface formalism developed previously for the orbifold {T}^6/(Z_2× Z_6) with discrete torsion and adapt it to the (Z_2× Z_6× Ω R) point group by modding out the remaining Z_3 subsymmetry and the orientifold projection Ω R. We first study the local behaviour of the Z_3× Ω R invariant deformation orbits under non-zero deformation and then develop methods to assess the deformation effects on the fractional three-cycle volumes globally. We confirm that D6-branes supporting USp(2 N) or SO(2 N) gauge groups do not constrain any deformation, while deformation parameters associated to cycles wrapped by D6-branes with U( N) gauge groups are constrained by D-term supersymmetry breaking. These features are exposed in global prototype MSSM, Left-Right symmetric and Pati-Salam models first constructed in [1, 2], for which we here count the number of stabilised moduli and study flat directions changing the values of some gauge couplings.

Cascading gauge theory on dS4 and String Theory landscape

NASA Astrophysics Data System (ADS)

Buchel, Alex; Galante, Damián A.

2014-06-01

Placing anti-D3 branes at the tip of the conifold in Klebanov-Strassler geometry provides a generic way of constructing meta-stable de Sitter (dS) vacua in String Theory. A local geometry of such vacua exhibit gravitational solutions with a D3 charge measured at the tip opposite to the asymptotic charge. We discuss a restrictive set of such geometries, where anti-D3 branes are smeared at the tip. Such geometries represent holographic dual of cascading gauge theory in dS4 with or without chiral symmetry breaking. We find that in the phase with unbroken chiral symmetry the D3 charge at the tip is always positive. Furthermore, this charge is zero in the phase with spontaneously broken chiral symmetry. We show that the effective potential of the chirally symmetric phase is lower than that in the symmetry broken phase, i.e., there is no spontaneous chiral symmetry breaking for cascading gauge theory in dS4. The positivity of the D3 brane charge in smooth de-Sitter deformed conifold geometries with fluxes presents difficulties in uplifting AdS vacua to dS ones in String Theory via smeared anti-D3 branes. First, turning on fluxes on Calabi-Yau compactifications of type IIB string theory produces highly warped geometry with stabilized complex structure (but not Kähler) moduli of the compactification [3]; Next, including non-perturbative effects (which are under control given the unbroken supersymmetry), one obtains anti-de Sitter (AdS4) vacua with all moduli fixed; Finally, one uses anti-D3 branes of type IIB string theory to uplift AdS4 to de Sitter (dS4) vacua. As the last step of the construction completely breaks supersymmetry, it is much less controlled. In fact, in [4-7] it was argued that putting anti-D3 branes at the tip of the Klebanov-Strassler (KS) [8] geometry (as done in KKLT construction) leads to a naked singularity. Whether or not the resulting singularity is physical is subject to debates. When M4=dS4 and the chiral symmetry is unbroken, the D3 brane

Viability of Noether Symmetry of F( R) Theory of Gravity

NASA Astrophysics Data System (ADS)

Sarkar, Kaushik; Sk, Nayem; Debnath, Subhra; Sanyal, Abhik Kumar

2013-04-01

Recently, we have explored vices and virtues of R^{3/2} term in the action which has in-built Noether symmetry and anticipated that a linear term might improve the situation (Sarkar et al., arXiv:1201.2987 [astro-ph.CO], 2012). In the absence of a conserved current it is extremely difficult to obtain an analytical solution of the said fourth order theory of gravity in the presence of a linear term. Here, we therefore enlarge the configuration space by including a scalar field in addition and also taking some of the anisotropic models (in the absence of a scalar field) into account. We observe that Noether symmetry remains obscure and it does not even reproduce the one that already exists in the literature (Sanyal, Gen. Relativ. Gravit., 37:407, 2005). However, there exists in general, a conserved current for F( R) theory of gravity in the presence of a non-minimally coupled scalar field (Sanyal, Phys. Lett. B, 624:81, 2005; Mod. Phys. Lett. A, 25:2667, 2010), which simplifies the field equations considerably. Here, we briefly expatiate the non-Noether conserved current and show that indeed the situation is modified.

FAST TRACK COMMUNICATION: Symmetry breaking, conformal geometry and gauge invariance

NASA Astrophysics Data System (ADS)

Ilderton, Anton; Lavelle, Martin; McMullan, David

2010-08-01

When the electroweak action is rewritten in terms of SU(2) gauge-invariant variables, the Higgs can be interpreted as a conformal metric factor. We show that asymptotic flatness of the metric is required to avoid a Gribov problem: without it, the new variables fail to be nonperturbatively gauge invariant. We also clarify the relations between this approach and unitary gauge fixing, and the existence of similar transformations in other gauge theories.

Integral group actions on symmetric spaces and discrete duality symmetries of supergravity theories

DOE Office of Scientific and Technical Information (OSTI.GOV)

Carbone, Lisa; Murray, Scott H.; Sati, Hisham

For G = G(ℝ), a split, simply connected, semisimple Lie group of rank n and K the maximal compact subgroup of G, we give a method for computing Iwasawa coordinates of K∖G using the Chevalley generators and the Steinberg presentation. When K∖G is a scalar coset for a supergravity theory in dimensions ≥3, we determine the action of the integral form G(ℤ) on K∖G. We give explicit results for the action of the discrete U-duality groups SL{sub 2}(ℤ) and E{sub 7}(ℤ) on the scalar cosets SO(2)∖SL{sub 2}(ℝ) and [SU(8)/( ± Id)]∖E{sub 7(+7)}(ℝ) for type IIB supergravity in ten dimensions andmore » 11-dimensional supergravity reduced to D = 4 dimensions, respectively. For the former, we use this to determine the discrete U-duality transformations on the scalar sector in the Borel gauge and we describe the discrete symmetries of the dyonic charge lattice. We determine the spectrum-generating symmetry group for fundamental BPS solitons of type IIB supergravity in D = 10 dimensions at the classical level and we propose an analog of this symmetry at the quantum level. We indicate how our methods can be used to study the orbits of discrete U-duality groups in general.« less

Gauge copies in the Landau-DeWitt gauge: A background invariant restriction

NASA Astrophysics Data System (ADS)

Dudal, David; Vercauteren, David

2018-04-01

The Landau background gauge, also known as the Landau-DeWitt gauge, has found renewed interest during the past decade given its usefulness in accessing the confinement-deconfinement transition via the vacuum expectation value of the Polyakov loop, describable via an appropriate background. In this Letter, we revisit this gauge from the viewpoint of it displaying gauge (Gribov) copies. We generalize the Gribov-Zwanziger effective action in a BRST and background invariant way; this action leads to a restriction on the allowed gauge fluctuations, thereby eliminating the infinitesimal background gauge copies. The explicit background invariance of our action is in contrast with earlier attempts to write down and use an effective Gribov-Zwanziger action. It allows to address certain subtleties arising in these earlier works, such as a spontaneous and thus spurious Lorentz symmetry breaking, something which is now averted.

SU(5)×U(1)X grand unification with minimal seesaw and Z‧-portal dark matter

NASA Astrophysics Data System (ADS)

Okada, Nobuchika; Okada, Satomi; Raut, Digesh

2018-05-01

We propose a grand unified SU (5) × U(1)X model, where the standard SU(5) grand unified theory is supplemented by minimal seesaw and a right-handed neutrino dark matter with an introduction of a global Z2-parity. In the presence of three right-handed neutrinos (RHNs), the model is free from all gauge and mixed-gravitational anomalies. The SU(5) symmetry is broken into the Standard Model (SM) gauge group at MGUT ≃ 4 ×1016GeV in the standard manner, while the U(1)X symmetry breaking occurs at the TeV scale, which generates the TeV-scale mass of the U(1)X gauge boson (Z‧ boson) and the three Majorana RHNs. A unique Z2-odd RHN is stable and serves as the dark matter (DM) in the present Universe, while the remaining two RHNs work to generate the SM neutrino masses through the minimal seesaw. We investigate the Z‧-portal RHN DM scenario in this model context. We find that the constraints from the DM relic abundance, and the Z‧ boson search at the Large Hadron Collider (LHC), and the perturbativity bound on the U(1)X gauge coupling are complementary to narrow down the allowed parameter region in the range of 3.0 ≤mZ‧ [TeV ] ≤ 9.2 for the Z‧ boson mass. The allowed region for mZ‧ ≤ 5TeV will be fully covered by the future LHC experiments. We also briefly discuss the successful implementation of Baryogenesis and cosmological inflation scenarios in the present model.

Flavor non-universal gauge interactions and anomalies in B-meson decays

NASA Astrophysics Data System (ADS)

Tang, Yong; Wu, Yue-Liang

2018-02-01

Motivated by flavor non-universality and anomalies in semi-leptonic B-meson decays, we present a general and systematic discussion about how to construct anomaly-free U(1)‧ gauge theories based on an extended standard model with only three right-handed neutrinos. If all standard model fermions are vector-like under this new gauge symmetry, the most general family non-universal charge assignments, (a,b,c) for three-generation quarks and (d,e,f) for leptons, need satisfy just one condition to be anomaly-free, 3(a+b+c) = - (d+e+f). Any assignment can be linear combinations of five independent anomaly-free solutions. We also illustrate how such models can generally lead to flavor-changing interactions and easily resolve the anomalies in B-meson decays. Probes with {{B}}{s} - {{\\bar B}}{s} mixing, decay into τ ±, dilepton and dijet searches at colliders are also discussed. Supported by the Grant-in-Aid for Innovative Areas (16H06490)

Digital lattice gauge theories

NASA Astrophysics Data System (ADS)

Zohar, Erez; Farace, Alessandro; Reznik, Benni; Cirac, J. Ignacio

2017-02-01

We propose a general scheme for a digital construction of lattice gauge theories with dynamical fermions. In this method, the four-body interactions arising in models with 2 +1 dimensions and higher are obtained stroboscopically, through a sequence of two-body interactions with ancillary degrees of freedom. This yields stronger interactions than the ones obtained through perturbative methods, as typically done in previous proposals, and removes an important bottleneck in the road towards experimental realizations. The scheme applies to generic gauge theories with Lie or finite symmetry groups, both Abelian and non-Abelian. As a concrete example, we present the construction of a digital quantum simulator for a Z3 lattice gauge theory with dynamical fermionic matter in 2 +1 dimensions, using ultracold atoms in optical lattices, involving three atomic species, representing the matter, gauge, and auxiliary degrees of freedom, that are separated in three different layers. By moving the ancilla atoms with a proper sequence of steps, we show how we can obtain the desired evolution in a clean, controlled way.

Explaining the 3.5 keV X-ray line in a Lμ‑Lτ extension of the inert doublet model

NASA Astrophysics Data System (ADS)

Biswas, Anirban; Choubey, Sandhya; Covi, Laura; Khan, Sarif

2018-02-01

We explain the existence of neutrino masses and their flavour structure, dark matter relic abundance and the observed 3.5 keV X-ray line within the framework of a gauged U(1)Lμ ‑ Lτ extension of the "scotogenic" model. In the U(1)Lμ ‑ Lτ symmetric limit, two of the RH neutrinos are degenerate in mass, while the third is heavier. The U(1)Lμ ‑ Lτ symmetry is broken spontaneously. Firstly, this breaks the μ‑τ symmetry in the light neutrino sector. Secondly, this results in mild splitting of the two degenerate RH neutrinos, with their mass difference given in terms of the U(1)Lμ ‑ Lτ breaking parameter. Finally, we get a massive Zμτ gauge boson. Due to the added Z2 symmetry under which the RH neutrinos and the inert doublet are odd, the canonical Type-I seesaw is forbidden and the tiny neutrino masses are generated radiatively at one loop. The same Z2 symmetry also ensures that the lightest RH neutrino is stable and the other two can only decay into the lightest one. This makes the two nearly-degenerate lighter neutrinos a two-component dark matter, which in our model are produced by the freeze-in mechanism via the decay of the Zμτ gauge boson in the early universe. We show that the next-to-lightest RH neutrino has a very long lifetime and decays into the lightest one at the present epoch explaining the observed 3.5 keV line.

Hyperunified field theory and gravitational gauge-geometry duality

NASA Astrophysics Data System (ADS)

Wu, Yue-Liang

2018-01-01

A hyperunified field theory is built in detail based on the postulates of gauge invariance and coordinate independence along with the conformal scaling symmetry. All elementary particles are merged into a single hyper-spinor field and all basic forces are unified into a fundamental interaction governed by the hyper-spin gauge symmetry SP(1, D_h-1). The dimension D_h of hyper-spacetime is conjectured to have a physical origin in correlation with the hyper-spin charge of elementary particles. The hyper-gravifield fiber bundle structure of biframe hyper-spacetime appears naturally with the globally flat Minkowski hyper-spacetime as a base spacetime and the locally flat hyper-gravifield spacetime as a fiber that is viewed as a dynamically emerged hyper-spacetime characterized by a non-commutative geometry. The gravitational origin of gauge symmetry is revealed with the hyper-gravifield that plays an essential role as a Goldstone-like field. The gauge-gravity and gravity-geometry correspondences bring about the gravitational gauge-geometry duality. The basic properties of hyperunified field theory and the issue on the fundamental scale are analyzed within the framework of quantum field theory, which allows us to describe the laws of nature in deriving the gauge gravitational equation with the conserved current and the geometric gravitational equations of Einstein-like type and beyond.

Light sterile neutrinos, dark matter, and new resonances in a U(1) extension of the MSSM

NASA Astrophysics Data System (ADS)

Hebbar, A.; Lazarides, G.; Shafi, Q.

2017-09-01

We present ψ'MSSM, a model based on a U(1) ψ' extension of the minimal supersymmetric standard model. The gauge symmetry U(1)ψ', also known as U(1)N,is a linear combination of the U(1) χ and U(1)ψ subgroups of E6. The model predicts the existence of three sterile neutrinos with masses ≲0.1 eV , if the U(1)ψ' breaking scale is of order 10 TeV. Their contribution to the effective number of neutrinos at nucleosynthesis is Δ Nν≃0.29. The model can provide a variety of possible cold dark matter candidates including the lightest sterile sneutrino. If the U(1) ψ' breaking scale is increased to 1 03 TeV , the sterile neutrinos, which are stable on account of a Z2symmetry, become viable warm dark matter candidates. The observed value of the standard model Higgs boson mass can be obtained with relatively light stop quarks thanks to the D-term contribution from U(1)ψ'. The model predicts diquark and diphoton resonances which may be found at an updated LHC. The well-known μ problem is resolved and the observed baryon asymmetry of the universe can be generated via leptogenesis. The breaking of U(1)ψ' produces superconducting strings that may be present in our galaxy. A U(1) R symmetry plays a key role in keeping the proton stable and providing the light sterile neutrinos.

Phenomenology of U(1)F extension of inert-doublet model with exotic scalars and leptons

NASA Astrophysics Data System (ADS)

Dhargyal, Lobsang

2018-02-01

In this work we will extend the inert-doublet model (IDM) by adding a new U(1)F gauge symmetry to it, under which, a Z2 even scalar (φ 2) and Z2 odd right handed component of two exotic charged leptons (F_{eR}, F_{μ R}), are charged. We also add one Z2 even real scalar (φ 1) and one complex scalar (φ ), three neutral Majorana right handed fermions (N1, N2, N3), two left handed components of the exotic charged leptons (F_{eL}, F_{μ L}) as well as F_{τ } are all odd under the Z2, all of which are not charged under the U(1)F. With these new particles added to the IDM, we have a model which can give two scalar DM candidates, together they can explain the present DM relic density as well as the muon (g-2) anomaly simultaneously. Also in this model the neutrino masses are generated at one loop level. One of the most peculiar feature of this model is that non-trivial solution to the axial gauge anomaly free conditions lead to the prediction of a stable very heavy partner to the electron (Fe), whose present collider limit (13 TeV LHC) on its mass should be around m_{Fe} ≥ few TeV.

R-Axion: A New LHC Physics Signature Involving Muon Pairs

DOE Office of Scientific and Technical Information (OSTI.GOV)

Goh, Hock-Seng; /UC, Berkeley /LBL, Berkeley; Ibe, Masahiro

2012-04-12

In a class of models with gauge mediated supersymmetry breaking, the existence of a light pseudo scalar particle, R-axion, with a mass in hundreds MeV range is predicted. The striking feature of such a light R-axion is that it mainly decays into a pair of muons and leaves a displaced vertex inside detectors once it is produced. In this talk, we show how we can search for the R-axion at the coming LHC experiments. The one main goal of the LHC experiments is discovering supersymmetry which has been anticipated for a long time to solve the hierarchy problem. Once themore » supersymmetric standard model (SSM) is confirmed experimentally, the next question is how the supersymmetry is broken and how the effects of symmetry breaking are mediated to the SSM sector. In most cases, such investigations on 'beyond the SSM physics' rely on arguments based on extrapolations of the observed supersymmetry mass parameters to higher energies. However, there is one class of models of supersymmetry breaking where we can get a direct glimpse of the structure of the hidden sector with the help of the R-symmetry. The R-symmetry plays an important role in rather generic models of spontaneous supersymmetry breaking. At the same time, however, it must be broken in some way in order for the gauginos in the SSM sector to have non-vanishing masses. One possibility of the gaugino mass generation is to consider models where the gaugino masses are generated as a result of the explicit breaking of the R-symmetries. Unfortunately, in those models, the R-symmetry leaves little trace for the collider experiments, since the mass of the R-axion is typically heavy and beyond the reach of the LHC experiments. In this talk, instead, we consider a class of models with gauge mediation where the R-symmetry in the hidden/messenger sectors is exact in the limit of the infinite reduced Planck scale, i.e. M{sub PL} {yields} {infinity}. In this case, the gaugino masses are generated only after the R-symmetry is

Formal and Applied AdS/CFT

NASA Astrophysics Data System (ADS)

Pufu, Silviu Stefan

The gauge/gravity duality is a powerful mathematical tool that relates strongly-interacting gauge theories with large numbers of colors to classical gravitational theories with negative cosmological constant. This thesis uses the gauge/gravity duality in two ways. The first half of the thesis explores the notion of a holographic p-wave superconductor/superfluid. On the gauge theory side there is an SU(2) global symmetry that is explicitly broken to U(1) by turning on a charge density. This U(1) symmetry is in turn spontaneously broken when the ratio between temperature and charge density is smaller than a critical value. The spontaneous breaking of the U(1) symmetry is accompanied by a spontaneous breaking of rotational symmetry. On the gravity side the SU(2) and U(1) symmetries are gauged, and the symmetry-broken backgrounds are charged black branes surrounded by clouds made of off-diagonal gauge bosons. The gauge/gravity duality is used to compute various critical exponents and transport coefficients related to the phase transition between the U(1) symmetry-broken and symmetry-restored phases. The second half of this thesis builds on the recent progress on using the technique of localization for computing supersymmetry-protected quantities in gauge theories with N ≥ 2 supersymmetry on the three-sphere. Using this technique, the infinite-dimensional path integrals of these theories were reduced to finite-dimensional multi-matrix integrals. In the second half of this thesis these multi-matrix integrals are computed approximately for the case of effective gauge theories on M2-branes probing various Calabi-Yau singularities. The answers match the predictions of the gauge/gravity duality. In particular, they reproduce the N3/2 scaling of the number of degrees of freedom on N coincident M2-branes.

Scalar field cosmology in f(R,T) gravity via Noether symmetry

NASA Astrophysics Data System (ADS)

Sharif, M.; Nawazish, Iqra

2018-04-01

This paper investigates the existence of Noether symmetries of isotropic universe model in f(R,T) gravity admitting minimal coupling of matter and scalar fields. The scalar field incorporates two dark energy models such as quintessence and phantom models. We determine symmetry generators and corresponding conserved quantities for two particular f(R,T) models. We also evaluate exact solutions and investigate their physical behavior via different cosmological parameters. For the first model, the graphical behavior of these parameters indicate consistency with recent observations representing accelerated expansion of the universe. For the second model, these parameters identify a transition form accelerated to decelerated expansion of the universe. The potential function is found to be constant for the first model while it becomes V(φ )≈ φ 2 for the second model. We conclude that the Noether symmetry generators and corresponding conserved quantities appear in all cases.

Novel symmetries in Christ-Lee model

NASA Astrophysics Data System (ADS)

Kumar, R.; Shukla, A.

2016-07-01

We demonstrate that the gauge-fixed Lagrangian of the Christ-Lee model respects four fermionic symmetries, namely; (anti-)BRST symmetries, (anti-)co-BRST symmetries within the framework of BRST formalism. The appropriate anticommutators amongst the fermionic symmetries lead to a unique bosonic symmetry. It turns out that the algebra obeyed by the symmetry transformations (and their corresponding conserved charges) is reminiscent of the algebra satisfied by the de Rham cohomological operators of differential geometry. We also provide the physical realizations of the cohomological operators in terms of the symmetry properties. Thus, the present model provides a simple model for the Hodge theory.

On the origin of Poincaré gauge gravity

NASA Astrophysics Data System (ADS)

Chkareuli, J. L.

2017-06-01

We argue that the origin of Poincaré gauge gravity (PGG) may be related to spontaneous violation of underlying spacetime symmetries involved and appearance of gauge fields as vector Goldstone bosons. In essence, we start with an arbitrary theory of some vector and fermion fields which possesses only global spacetime symmetries, such as Lorentz and translational invariance, in flat Minkowski space. The two vector field multiplets involved are assumed to belong, respectively, to the adjoint (Aμij) and vector (eμi) representations of the starting global Lorentz symmetry. We propose that these prototype vector fields are covariantly constrained, Aμij Aijμ = ±MA2 and eμi eiμ = ±Me2 , that causes a spontaneous violation of the accompanying global symmetries (MA,e are their presumed violation scales). It then follows that the only possible theory compatible with these length-preserving constraints is turned out to be the gauge invariant PGG, while the corresponding massless (pseudo)Goldstone modes are naturally collected in the emergent gauge fields of tetrads and spin-connections. In a minimal theory case being linear in a curvature we unavoidably come to the Einstein-Cartan theory. The extended theories with propagating spin-connection and tetrad modes are also considered and their possible unification with the Standard Model is briefly discussed.

Domain wall fermion and CP symmetry breaking

NASA Astrophysics Data System (ADS)

Fujikawa, Kazuo; Suzuki, Hiroshi

2003-02-01

We examine the CP properties of chiral gauge theory defined by a formulation of the domain wall fermion, where the light field variables q and q¯ together with Pauli-Villars fields Q and Q¯ are utilized. It is shown that this domain wall representation in the infinite flavor limit N=∞ is valid only in the topologically trivial sector, and that the conflict among lattice chiral symmetry, strict locality and CP symmetry still persists for finite lattice spacing a. The CP transformation generally sends one representation of lattice chiral gauge theory into another representation of lattice chiral gauge theory, resulting in the inevitable change of propagators. A modified form of lattice CP transformation motivated by the domain wall fermion, which keeps the chiral action in terms of the Ginsparg-Wilson fermion invariant, is analyzed in detail; this provides an alternative way to understand the breaking of CP symmetry at least in the topologically trivial sector. We note that the conflict with CP symmetry could be regarded as a topological obstruction. We also discuss the issues related to the definition of Majorana fermions in connection with the supersymmetric Wess-Zumino model on the lattice.

Argyres–Douglas theories, S 1 reductions, and topological symmetries

DOE PAGES

Buican, Matthew; Nishinaka, Takahiro

2015-12-21

In a recent paper, we proposed closed-form expressions for the superconformal indices of the (A(1), A(2n-3)) and(A(1), D-2n) Argyres-Douglas (AD) superconformal field theories (SCFTs) in the Schur limit. Following up on our results, we turn our attention to the small S-1 regime of these indices. As expected on general grounds, our study reproduces the S-3 partition functions of the resulting dimensionally reduced theories. However, we show that in all cases-with the exception of the reduction of the (A(1), D-4) SCFTcertain imaginary partners of real mass terms are turned on in the corresponding mirror theories. We interpret these deformations as Rmore » symmetry mixing with the topological symmetries of the direct S-1 reductions. Moreover, we argue that these shifts occur in any of our theories whose four-dimensional N = 2 superconformal U(1)(R) symmetry does not obey an SU(2) quantization condition. We then use our R symmetry map to find the fourdimensional ancestors of certain three-dimensional operators. Somewhat surprisingly, this picture turns out to imply that the scaling dimensions of many of the chiral operators of the four-dimensional theory are encoded in accidental symmetries of the three-dimensional theory. We also comment on the implications of our work on the space of general N = 2 SCFTs.« less

Argyres–Douglas theories, S 1 reductions, and topological symmetries

DOE Office of Scientific and Technical Information (OSTI.GOV)

Buican, Matthew; Nishinaka, Takahiro

In a recent paper, we proposed closed-form expressions for the superconformal indices of the (A(1), A(2n-3)) and(A(1), D-2n) Argyres-Douglas (AD) superconformal field theories (SCFTs) in the Schur limit. Following up on our results, we turn our attention to the small S-1 regime of these indices. As expected on general grounds, our study reproduces the S-3 partition functions of the resulting dimensionally reduced theories. However, we show that in all cases-with the exception of the reduction of the (A(1), D-4) SCFTcertain imaginary partners of real mass terms are turned on in the corresponding mirror theories. We interpret these deformations as Rmore » symmetry mixing with the topological symmetries of the direct S-1 reductions. Moreover, we argue that these shifts occur in any of our theories whose four-dimensional N = 2 superconformal U(1)(R) symmetry does not obey an SU(2) quantization condition. We then use our R symmetry map to find the fourdimensional ancestors of certain three-dimensional operators. Somewhat surprisingly, this picture turns out to imply that the scaling dimensions of many of the chiral operators of the four-dimensional theory are encoded in accidental symmetries of the three-dimensional theory. We also comment on the implications of our work on the space of general N = 2 SCFTs.« less

A Geometric Characterization of Certain First Integrals for Nonholonomic Systems with Symmetries

NASA Astrophysics Data System (ADS)

Balseiro, Paula; Sansonetto, Nicola

2016-02-01

We study the existence of first integrals in nonholonomic systems with symmetry. First we define the concept of M-cotangent lift of a vector field on a manifold Q in order to unify the works [Balseiro P., Arch. Ration. Mech. Anal. 214 (2014), 453-501, arXiv:1301.1091], [Fassò F., Ramos A., Sansonetto N., Regul. Chaotic Dyn. 12 (2007), 579-588], and [Fassò F., Giacobbe A., Sansonetto N., Rep. Math. Phys. 62 (2008), 345-367]. Second, we study gauge symmetries and gauge momenta, in the cases in which there are the symmetries that satisfy the so-called vertical symmetry condition. Under such condition we can predict the number of linearly independent first integrals (that are gauge momenta). We illustrate the theory with two examples.

Line defect Schur indices, Verlinde algebras and U(1) r fixed points

NASA Astrophysics Data System (ADS)

Neitzke, Andrew; Yan, Fei

2017-11-01

Given an N=2 superconformal field theory, we reconsider the Schur index ℐ L ( q) in the presence of a half line defect L. Recently Cordova-Gaiotto-Shao found that ℐ L ( q) admits an expansion in terms of characters of the chiral algebra A introduced by Beem et al., with simple coefficients υ L, β ( q). We report a puzzling new feature of this expansion: the q → 1 limit of the coefficients υ L, β ( q) is linearly related to the vacuum expectation values 〈 L〉 in U(1) r -invariant vacua of the theory compactified on S 1. This relation can be expressed algebraically as a commutative diagram involving three algebras: the algebra generated by line defects, the algebra of functions on U(1) r -invariant vacua, and a Verlindelike algebra associated to A . Our evidence is experimental, by direct computation in the Argyres-Douglas theories of type ( A 1, A 2), ( A 1, A 4), ( A 1, A 6), ( A 1, D 3) and ( A 1, D 5). In the latter two theories, which have flavor symmetries, the Verlinde-like algebra which appears is a new deformation of algebras previously considered.

The DEAH-box helicase Dhr1 dissociates U3 from the pre-rRNA to promote formation of the central pseudoknot.

PubMed

Sardana, Richa; Liu, Xin; Granneman, Sander; Zhu, Jieyi; Gill, Michael; Papoulas, Ophelia; Marcotte, Edward M; Tollervey, David; Correll, Carl C; Johnson, Arlen W

2015-02-01

In eukaryotes, the highly conserved U3 small nucleolar RNA (snoRNA) base-pairs to multiple sites in the pre-ribosomal RNA (pre-rRNA) to promote early cleavage and folding events. Binding of the U3 box A region to the pre-rRNA is mutually exclusive with folding of the central pseudoknot (CPK), a universally conserved rRNA structure of the small ribosomal subunit essential for protein synthesis. Here, we report that the DEAH-box helicase Dhr1 (Ecm16) is responsible for displacing U3. An active site mutant of Dhr1 blocked release of U3 from the pre-ribosome, thereby trapping a pre-40S particle. This particle had not yet achieved its mature structure because it contained U3, pre-rRNA, and a number of early-acting ribosome synthesis factors but noticeably lacked ribosomal proteins (r-proteins) that surround the CPK. Dhr1 was cross-linked in vivo to the pre-rRNA and to U3 sequences flanking regions that base-pair to the pre-rRNA including those that form the CPK. Point mutations in the box A region of U3 suppressed a cold-sensitive mutation of Dhr1, strongly indicating that U3 is an in vivo substrate of Dhr1. To support the conclusions derived from in vivo analysis we showed that Dhr1 unwinds U3-18S duplexes in vitro by using a mechanism reminiscent of DEAD box proteins.

The DEAH-box Helicase Dhr1 Dissociates U3 from the Pre-rRNA to Promote Formation of the Central Pseudoknot

PubMed Central

Granneman, Sander; Zhu, Jieyi; Gill, Michael; Papoulas, Ophelia; Marcotte, Edward M.; Tollervey, David; Correll, Carl C.; Johnson, Arlen W.

2015-01-01

In eukaryotes, the highly conserved U3 small nucleolar RNA (snoRNA) base-pairs to multiple sites in the pre-ribosomal RNA (pre-rRNA) to promote early cleavage and folding events. Binding of the U3 box A region to the pre-rRNA is mutually exclusive with folding of the central pseudoknot (CPK), a universally conserved rRNA structure of the small ribosomal subunit essential for protein synthesis. Here, we report that the DEAH-box helicase Dhr1 (Ecm16) is responsible for displacing U3. An active site mutant of Dhr1 blocked release of U3 from the pre-ribosome, thereby trapping a pre-40S particle. This particle had not yet achieved its mature structure because it contained U3, pre-rRNA, and a number of early-acting ribosome synthesis factors but noticeably lacked ribosomal proteins (r-proteins) that surround the CPK. Dhr1 was cross-linked in vivo to the pre-rRNA and to U3 sequences flanking regions that base-pair to the pre-rRNA including those that form the CPK. Point mutations in the box A region of U3 suppressed a cold-sensitive mutation of Dhr1, strongly indicating that U3 is an in vivo substrate of Dhr1. To support the conclusions derived from in vivo analysis we showed that Dhr1 unwinds U3-18S duplexes in vitro by using a mechanism reminiscent of DEAD box proteins. PMID:25710520

FLRW Cosmology from Yang-Mills Gravity with Translational Gauge Symmetry

NASA Astrophysics Data System (ADS)

Katz, Daniel

2013-03-01

We extend to basic cosmology the subject of Yang-Mills gravity — a theory of gravity based on local translational gauge invariance in flat space-time. It has been shown that this particular gauge invariance leads to tensor factors in the macroscopic limit of the equations of motion of particles which plays the same role as the metric tensor of general relativity (GR). The assumption that this "effective metric" tensor takes on the standard FLRW form is our starting point. Equations analogous to the Friedmann equations are derived and then solved in closed form for the three special cases of a universe dominated by (1) matter, (2) radiation and (3) dark energy. We find that the solutions for the scale factor are similar to, but distinct from, those found in the corresponding GR based treatment.

Asymptotic symmetries of colored gravity in three dimensions

NASA Astrophysics Data System (ADS)

Joung, Euihun; Kim, Jaewon; Kim, Jihun; Rey, Soo-Jong

2018-03-01

Three-dimensional colored gravity refers to nonabelian isospin extension of Einstein gravity. We investigate the asymptotic symmetry algebra of the SU( N)-colored gravity in (2+1)-dimensional anti-de Sitter spacetime. Formulated by the Chern-Simons theory with SU( N, N) × SU( N, N) gauge group, the theory contains graviton, SU( N) Chern-Simons gauge fields and massless spin-two multiplets in the SU( N) adjoint representation, thus extending diffeomorphism to colored, nonabelian counterpart. We identify the asymptotic symmetry as Poisson algebra of generators associated with the residual global symmetries of the nonabelian diffeomorphism set by appropriately chosen boundary conditions. The resulting asymptotic symmetry algebra is a nonlinear extension of \\widehat{su(N)} Kac-Moody algebra, supplemented by additional generators corresponding to the massless spin-two adjoint matter fields.

Friedberg-Lee symmetry and tribimaximal neutrino mixing in the inverse seesaw mechanism

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chan, A.H.; Institute of Advanced Studies, Nanyang Technological University, Singapore 639673; Department of Physics, National University of Singapore, Singapore 117542

2009-10-01

The inverse seesaw mechanism with three pairs of gauge-singlet neutrinos offers a natural interpretation of the tiny masses of three active neutrinos at the TeV scale. We combine this picture with the newly proposed Friedberg-Lee (FL) symmetry in order to understand the observed pattern of neutrino mixing. We show that the FL symmetry requires only two pairs of the gauge-singlet neutrinos to be massive, implying that one active neutrino must be massless. We propose a phenomenological ansatz with broken FL symmetry and exact {mu}-{tau} symmetry in the gauge-singlet neutrino sector, and obtain the tribimaximal neutrino mixing pattern by means ofmore » the inverse seesaw relation. We demonstrate that nonunitary corrections to this result can possibly reach the percent level, and a soft breaking of {mu}-{tau} symmetry can give rise to CP violation in such a TeV-scale seesaw scenario.« less

Adding gauge fields to Kaplan's fermions

NASA Astrophysics Data System (ADS)

Blum, T.; Kärkkäinen, Leo

1994-04-01

We experiment with adding dynamical gauge field to Kaplan (defect) fermions. In the case of U (1) gauge theory we use an inhomogenous Higgs mechanism to restrict the 3d gauge dynamics to a planar 2d defect. In our simulations the 3d theory produce the correct 2d gauge dynamics. We measure fermion propagators with dynamical gauge fields. They posses the correct chiral structure. The fermions at the boundary of the support of the gauge field (waveguide) are non-chiral, and have a mass two times heavier than the chiral modes. Moreover, these modes cannot be excited by a source at the defect; implying that they are dynamically decoupled. We have also checked that the anomaly relation is fullfilled for the case of a smooth external gauge field.

Evaluation of electron population terms for <r-3Se>4p, <r-3S>3p, and <r-3O>(2p): how do HOMO and LUMO shrink or expand depending on nuclear charges?

PubMed

Nakanishi, Waro; Hayashi, Satoko; Narahara, Kenji; Yamaki, Daisuke; Hada, Masahiko

2008-01-01

Electron population terms <r(-3)N> are evaluated for N=Se, S, and O. Calculations are performed on HOMO and LUMO constructed by pure atomic 4p(Se), 3p(S), and 2p(O) orbitals, employing the 6-311+G(3d) and/or 6-311(++)G(3df,3pd) basis sets at the HF, MP2, and DFT (B3 LYP) levels. Se(4+), Se(2+), Se(0), and Se(2-) with the O(h) symmetry are called G(A: Se) and HSe(+), H(2)Se, and HSe(-) with the C(infinityh) or C(2v) symmetry are named G(B: Se), here [G(A+B: Se) in all]. HOMO and LUMO in G(A+B: N) (N=Se, S, and O) satisfy the conditions of the calculations for <r(-3)N>. The <r(-3)Se>(4p), <r(-3)S>(3p), and <r(-3)O>(2p) values correlate well with the corresponding MO energies (epsilon(N)) for all calculation levels employed. Plots of <r(-3)N>(HOMO) and <r(-3)N>(LUMO) versus Q(N) (N=Se, S, and O) at the HF and MP2 levels are analyzed as two correlations. However, the plots at the DFT level can be analyzed as single correlation. A regression curve is assumed for the analysis. Behaviors of <r(-3)N> clarify how valence orbitals shrink or expand depending on Q(N). The applicability of <r(-3)N> is examined to establish a new method that enables us to analyze chemical shifts with the charge effect separately from others. A utility program derived from the Gaussian 03 (NMRANAL-NH03G) is applied to evaluate <r(-3)N> and examine the applicability to the NMR analysis.

Heavy charged scalars from c\\overline{s} fusion: a generic search strategy applied to a 3HDM with U(1) × U(1) family symmetry

NASA Astrophysics Data System (ADS)

Camargo-Molina, José Eliel; Mandal, Tanumoy; Pasechnik, Roman; Wessén, Jonas

2018-03-01

We describe a class of three Higgs doublet models (3HDMs) with a softly broken U(1) × U(1) family symmetry that enforces a Cabibbo-like quark mixing while forbidding tree-level flavour changing neutral currents. The hierarchy in the observed quark masses is partly explained by a softer hierarchy in the vacuum expectation values of the three Higgs doublets. As a consequence, the physical scalar spectrum contains a Standard Model (SM) like Higgs boson h 125 while exotic scalars couple the strongest to the second quark family, leading to rather unconventional discovery channels that could be probed at the Large Hadron Collider. In particular, we describe a search strategy for the lightest charged Higgs boson H ±, through the process c\\overline{s}\\to {H}+\\to {W}+{h}_{125} , using a multivariate analysis that leads to an excellent discriminatory power against the SM background. Although the analysis is applied to the proposed class of 3HDMs, we employ a model-independent formulation such that it can be applied to any other model with the same discovery channel.

Quantization of a U(1) gauged chiral boson in the Batalin-Fradkin-Vilkovisky scheme

NASA Astrophysics Data System (ADS)

Ghosh, Subir

1994-03-01

The scheme developed by Batalin, Fradkin, and Vilkovisky (BFV) to convert a second-class constrained system to a first-class one (having gauge invariance) is used in the Floreanini-Jackiw formulation of the chiral boson interacting with a U(1) gauge field. Explicit expressions of the BRST charge, the unitarizing Hamiltonian, and the BRST invariant effective action are provided and the full quantization is carried through. The spectra in both cases have been analyzed to show the presence of the proper chiral components explicitly. In the gauged model, Wess-Zumino terms in terms of the Batalin-Fradkin fields are identified.

Quantization of a U(1) gauged chiral boson in the Batalin-Fradkin-Vilkovisky scheme

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ghosh, S.

1994-03-15

The scheme developed by Batalin, Fradkin, and Vilkovisky (BFV) to convert a second-class constrained system to a first-class one (having gauge invariance) is used in the Floreanini-Jackiw formulation of the chiral boson interacting with a U(1) gauge field. Explicit expressions of the BRST charge, the unitarizing Hamiltonian, and the BRST invariant effective action are provided and the full quantization is carried through. The spectra in both cases have been analyzed to show the presence of the proper chiral components explicitly. In the gauged model, Wess-Zumino terms in terms of the Batalin-Fradkin fields are identified.

Bose-Einstein condensation of triplons with a weakly broken U(1) symmetry

NASA Astrophysics Data System (ADS)

Khudoyberdiev, Asliddin; Rakhimov, Abdulla; Schilling, Andreas

2017-11-01

The low-temperature properties of certain quantum magnets can be described in terms of a Bose-Einstein condensation (BEC) of magnetic quasiparticles (triplons). Some mean-field approaches (MFA) to describe these systems, based on the standard grand canonical ensemble, do not take the anomalous density into account and leads to an internal inconsistency, as it has been shown by Hohenberg and Martin, and may therefore produce unphysical results. Moreover, an explicit breaking of the U(1) symmetry as observed, for example, in TlCuCl3 makes the application of MFA more complicated. In the present work, we develop a self-consistent MFA approach, similar to the Hartree-Fock-Bogolyubov approximation in the notion of representative statistical ensembles, including the effect of a weakly broken U(1) symmetry. We apply our results on experimental data of the quantum magnet TlCuCl3 and show that magnetization curves and the energy dispersion can be well described within this approximation assuming that the BEC scenario is still valid. We predict that the shift of the critical temperature T c due to a finite exchange anisotropy is rather substantial even when the anisotropy parameter γ is small, e.g., {{Δ }}{T}{c}≈ 10 % of T c in H = 6 T and for γ ≈ 4 μ {eV}.

Ideal walking dynamics via a gauged NJL model

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rantaharju, Jarno; Pica, Claudio; Sannino, Francesco

According to the ideal walking technicolor paradigm, large mass anomalous dimensions arise in gauged Nambu–Jona-Lasinio (NJL) models when the four-fermion coupling is sufficiently strong to induce spontaneous symmetry breaking in an otherwise conformal gauge theory. Therefore, we study the SU(2) gauged NJL model with two adjoint fermions using lattice simulations. The model is in an infrared conformal phase at small NJL coupling while it displays a chirally broken phase at large NJL couplings. In the infrared conformal phase, we find that the mass anomalous dimension varies with the NJL coupling, reaching γm ~ 1 close to the chiral symmetry breakingmore » transition, de facto making the present model the first explicit realization of the ideal walking scenario.« less

Ideal walking dynamics via a gauged NJL model

DOE PAGES

Rantaharju, Jarno; Pica, Claudio; Sannino, Francesco

2017-07-25

According to the ideal walking technicolor paradigm, large mass anomalous dimensions arise in gauged Nambu–Jona-Lasinio (NJL) models when the four-fermion coupling is sufficiently strong to induce spontaneous symmetry breaking in an otherwise conformal gauge theory. Therefore, we study the SU(2) gauged NJL model with two adjoint fermions using lattice simulations. The model is in an infrared conformal phase at small NJL coupling while it displays a chirally broken phase at large NJL couplings. In the infrared conformal phase, we find that the mass anomalous dimension varies with the NJL coupling, reaching γm ~ 1 close to the chiral symmetry breakingmore » transition, de facto making the present model the first explicit realization of the ideal walking scenario.« less

Large gauge transformations and little group for soft photons

NASA Astrophysics Data System (ADS)

Hamada, Yuta; Seo, Min-Seok; Shiu, Gary

2017-11-01

Recently, large gauge transformation (LGT), the residual gauge symmetry after gauge fixing that survives at null infinity, has drawn much attention concerning soft theorems and the memory effect. We point out that LGT charges in quantum electrodynamics are in fact one of noncompact generators of the two dimensional Euclidean group. Moreover, by comparing two equivalent descriptions of gauge transformation, we suggest that LGT is simply another way of describing the gauged little group for massless soft photons.

Multiple normalized solutions for a planar gauged nonlinear Schrödinger equation

NASA Astrophysics Data System (ADS)

Luo, Xiao

2018-06-01

We study the existence, multiplicity, quantitative property and asymptotic behavior of normalized solutions for a gauged nonlinear Schrödinger equation arising from the Chern-Simons theory Δ u + ω u +|x|^2u+ λ ( {{h^2}(| x | )}/{{{| x | ^2}}} + \\int \\limits _{| x | }^{ + ∞} {{h(s)}/s} {u^2}(s)ds) u = {| u | ^{p - 2}}u,\\quad x\\in R^2, where ω \\in R, λ >0, p>4 and h(s) = 1/2\\int \\limits _0^s {r{u^2}(r)dr} . Combining constraint minimization method and minimax principle, we prove that the problem possesses at least two normalized solutions: One is a ground state and the other is an excited state. Furthermore, the asymptotic behavior and quantitative property of the ground state are analyzed.

Probing the holographic principle using dynamical gauge effects from open spin-orbit coupling

NASA Astrophysics Data System (ADS)

Zhao, Jianshi; Price, Craig; Liu, Qi; Gemelke, Nathan

2016-05-01

Dynamical gauge fields result from locally defined symmetries and an effective over-labeling of quantum states. Coupling atoms weakly to a reservoir of laser modes can create an effective dynamical gauge field purely due to the disregard of information in the optical states. Here we report measurements revealing effects of open spin-orbit coupling in a system where an effective model can be formed from a non-abelian SU(2) × U(1) field theory following the Yang-Mills construct. Forming a close analogy to dynamical gauge effects in quantum chromodynamics, we extract a measure of atomic motion which reveals the analog of a closing mass gap for the relevant gauge boson, shedding insight on long standing open problems in gauge-fixing scale anomalies. Using arguments following the holographic principle, we measure scaling relations which can be understood by quantifying information present in the local potential. New prospects using these techniques for developing fractionalization of multi-particle and macroscopic systems using dissipative and non-abelian gauge fields will also be discussed. We acknowledge support from NSF Award No. 1068570, and the Charles E. Kaufman Foundation.

Gluon dynamics, center symmetry, and the deconfinement phase transition in SU(3) pure Yang-Mills theory

NASA Astrophysics Data System (ADS)

Silva, P. J.; Oliveira, O.

2016-06-01

The correlations between the modulus of the Polyakov loop, its phase θ , and the Landau gauge gluon propagator at finite temperature are investigated in connection with the center symmetry for pure Yang-Mills SU(3) theory. In the deconfined phase, where the center symmetry is spontaneously broken, the phase of the Polyakov loop per configuration is close to θ =0 , ±2 π /3 . We find that the gluon propagator form factors associated with θ ≈0 differ quantitatively and qualitatively from those associated to θ ≈±2 π /3 . This difference between the form factors is a property of the deconfined phase and a sign of the spontaneous breaking of the center symmetry. Furthermore, given that this difference vanishes in the confined phase, it can be used as an order parameter associated to the deconfinement transition. For simulations near the critical temperature Tc, the difference between the propagators associated to θ ≈0 and θ ≈±2 π /3 allows one to classify the configurations as belonging to the confined or deconfined phase. This establishes a selection procedure which has a measurable impact on the gluon form factors. Our results also show that the absence of the selection procedure can be erroneously interpreted as lattice artifacts.

U(1){sub R} mediation from the flux compactification in six dimensions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lee, Hyun Min

We consider a supersymmetric completion of codimension-two branes with nonzero tension in a 6D gauged supergravity. As a consequence, we obtain the football solution with 4D Minkowski space as a new supersymmetric background that preserves 4D N = 1 SUSY. In the presence of brane multiplets, we derive the 4D effective supergravity action for the football background and show that the remaining modulus can be stabilized by a bulk non-perturbative correction with brane uplifting potentials at a zero vacuum energy. We find that the U(1){sub R} mediation can be a dominant source of SUSY breaking for a brane scalar withmore » nonzero R charge.« less

The {{\\rm{D}}\\bar{{\\rm{D}}}}^{{\\rm{* }}} interaction with isospin zero in an extended hidden gauge symmetry approach

NASA Astrophysics Data System (ADS)

Sun, Bao-Xi; Wan, Da-Ming; Zhao, Si-Yu

2018-05-01

The {{{D}}\\bar{{{D}}}}{{* }} interaction via a ρ or ω exchange is constructed within an extended hidden gauge symmetry approach, where the strange quark is replaced by the charm quark in the SU(3) flavor space. With this {{{D}}\\bar{{{D}}}}{{* }} interaction, a bound state slightly lower than the {{{D}}\\bar{{{D}}}}{{* }} threshold is generated dynamically in the isospin zero sector by solving the Bethe-Salpeter equation in the coupled-channel approximation, which might correspond to the X(3872) particle announced by many collaborations. This formulism is also used to study the {{{B}}\\bar{{{B}}}}{{* }} interaction, and a {{{B}}\\bar{{{B}}}}{{* }} bound state with isospin zero is generated dynamically, which has no counterpart listed in the review of the Particle Data Group. Furthermore, the one-pion exchange between the D meson and the {\\bar{{{D}}}}{{* }} is analyzed precisely, and we do not think the one-pion exchange potential need be considered when the Bethe-Salpeter equation is solved.

Supersymmetric Gauge Theories with Decoupled Operators and Chiral Ring Stability

NASA Astrophysics Data System (ADS)

Benvenuti, Sergio; Giacomelli, Simone

2017-12-01

We propose a general way to complete supersymmetric theories with operators below the unitarity bound, adding gauge-singlet fields that enforce the decoupling of such operators. This makes it possible to perform all usual computations, and to compactify on a circle. We concentrate on a duality between an N =1 SU(2) gauge theory and the N =2 A3 Argyres-Douglas theory, mapping the moduli space and chiral ring of the completed N =1 theory to those of the A3 model. We reduce the completed gauge theory to 3D, finding a 3D duality with N =4 supersymmetric QED (SQED) with two flavors. The naive dimensional reduction is instead N =2 SQED. Crucial is a concept of chiral ring stability, which modifies the superpotential and allows for a 3D emergent global symmetry.

BOOK REVIEW: Symmetry Breaking

NASA Astrophysics Data System (ADS)

Ryder, L. H.

2005-11-01

One of the most fruitful and enduring advances in theoretical physics during the last half century has been the development of the role played by symmetries. One needs only to consider SU(3) and the classification of elementary particles, the Yang Mills enlargement of Maxwell's electrodynamics to the symmetry group SU(2), and indeed the tremendous activity surrounding the discovery of parity violation in the weak interactions in the late 1950s. This last example is one of a broken symmetry, though the symmetry in question is a discrete one. It was clear to Gell-Mann, who first clarified the role of SU(3) in particle physics, that this symmetry was not exact. If it had been, it would have been much easier to discover; for example, the proton, neutron, Σ, Λ and Ξ particles would all have had the same mass. For many years the SU(3) symmetry breaking was assigned a mathematical form, but the importance of this formulation fell away when the quark model began to be taken seriously; the reason the SU(3) symmetry was not exact was simply that the (three, in those days) quarks had different masses. At the same time, and in a different context, symmetry breaking of a different type was being investigated. This went by the name of `spontaneous symmetry breaking' and its characteristic was that the ground state of a given system was not invariant under the symmetry transformation, though the interactions (the Hamiltonian, in effect) was. A classic example is ferromagnetism. In a ferromagnet the atomic spins are aligned in one direction only—this is the ground state of the system. It is clearly not invariant under a rotation, for that would change the ground state into a (similar but) different one, with the spins aligned in a different direction; this is the phenomenon of a degenerate vacuum. The contribution of the spin interaction, s1.s2, to the Hamiltonian, however, is actually invariant under rotations. As Coleman remarked, a little man living in a ferromagnet would

Gauge mediated mini-split

DOE PAGES

Cohen, Timothy; Craig, Nathaniel; Knapen, Simon

2016-03-15

We propose a simple model of split supersymmetry from gauge mediation. This model features gauginos that are parametrically a loop factor lighter than scalars, accommodates a Higgs boson mass of 125 GeV, and incorporates a simple solution to the μ–b μ problem. The gaugino mass suppression can be understood as resulting from collective symmetry breaking. Imposing collider bounds on μ and requiring viable electroweak symmetry breaking implies small a-terms and small tan β — the stop mass ranges from 10 5 to 10 8 GeV. In contrast with models with anomaly + gravity mediation (which also predict a one-loop loopmore » suppression for gaugino masses), our gauge mediated scenario predicts aligned squark masses and a gravitino LSP. Gluinos, electroweakinos and Higgsinos can be accessible at the LHC and/or future colliders for a wide region of the allowed parameter space.« less

Penguin b → sℓ‧+ℓ‧- and B-meson anomalies in a gauged Lμ - Lτ

NASA Astrophysics Data System (ADS)

Chen, Chuan-Hung; Nomura, Takaaki

2018-02-01

The Z‧-gauge boson in an U(1) Lμ -Lτ gauge symmetry has two interesting features: one is its vector couplings to the charged leptons, and the other is the decoupling from the electron. Based on these properties, we investigate the feasibility to simultaneously resolve the R K (*) = BR (B →K (*)μ+μ-) / BR (B →K (*)e+e-) and R D (*) = BR (B bar →D (*) τνbarτ) / BR (B bar →D (*) ℓνbarℓ) anomalies in an U(1) Lμ -Lτ model, where the former is expected to arise from the Z‧-penguin-induced b → sμ+μ- process and the latter from the tree-level b → cτνbarτ decay. In order to achieve the intended purpose, we employ one vector-like doublet lepton and one singlet scalar leptoquark (LQ), in which the new particles all carry the U(1) Lμ -Lτ charges; the b → sZ‧ effective interaction is generated from the vector-like lepton and LQ loop, and the b → cτνbarτ decay is induced from the LQ. When the constraints from the b → sγ, B+ →K+ ν ν bar , Bc- → τνbarτ, ΔF = 2, and τ → μℓ ℓ bar processes are included, it is found that RD and RD* can be enhanced to fit the experimental data, and the Wilson coefficient C9 from the LQ-loop can reach C9LQ, μ ∼ - 1, which can explain the RK and RK* anomalies. In addition, in this simple model, the Higgs lepton-flavor violating h → μτ decay can occur at the tree level, and its branching ratio can be as large as the current experimental upper limit.

Stokes' theorem, gauge symmetry and the time-dependent Aharonov-Bohm effect

DOE Office of Scientific and Technical Information (OSTI.GOV)

Macdougall, James, E-mail: jbm34@mail.fresnostate.edu; Singleton, Douglas, E-mail: dougs@csufresno.edu

2014-04-15

Stokes' theorem is investigated in the context of the time-dependent Aharonov-Bohm effect—the two-slit quantum interference experiment with a time varying solenoid between the slits. The time varying solenoid produces an electric field which leads to an additional phase shift which is found to exactly cancel the time-dependent part of the usual magnetic Aharonov-Bohm phase shift. This electric field arises from a combination of a non-single valued scalar potential and/or a 3-vector potential. The gauge transformation which leads to the scalar and 3-vector potentials for the electric field is non-single valued. This feature is connected with the non-simply connected topology ofmore » the Aharonov-Bohm set-up. The non-single valued nature of the gauge transformation function has interesting consequences for the 4-dimensional Stokes' theorem for the time-dependent Aharonov-Bohm effect. An experimental test of these conclusions is proposed.« less

Ambitwistor formulations of R 2 gravity and ( DF)2 gauge theories

NASA Astrophysics Data System (ADS)

Azevedo, Thales; Engelund, Oluf Tang

2017-11-01

We consider D-dimensional amplitudes in R 2 gravities (conformal gravity in D = 4) and in the recently introduced ( DF)2 gauge theory, from the perspective of the CHY formulae and ambitwistor string theory. These theories are related through the BCJ double-copy construction, and the ( DF)2 gauge theory obeys color-kinematics duality. We work out the worldsheet details of these theories and show that they admit a formulation as integrals on the support of the scattering equations, or alternatively, as ambitwistor string theories. For gravity, this generalizes the work done by Berkovits and Witten on conformal gravity to D dimensions. The ambitwistor is also interpreted as a D-dimensional generalization of Witten's twistor string (SYM + conformal supergravity). As part of our ambitwistor investigation, we discover another ( DF)2 gauge theory containing a photon that couples to Einstein gravity. This theory can provide an alternative KLT description of Einstein gravity compared to the usual Yang-Mills squared.

Dirac neutrinos with S4 flavor symmetry in warped extra dimensions

NASA Astrophysics Data System (ADS)

Ding, Gui-Jun; Zhou, Ye-Ling

2013-11-01

We present a warped extra dimension model with the custodial symmetry SU(2×SU(2×U(1×PLR based on the flavor symmetry S4×Z2×Z2', and the neutrinos are taken to be Dirac particles. At leading order, the democratic lepton mixing is derived exactly, and the high-dimensional operators introduce corrections of order λc to all the three lepton mixing angles such that agreement with the experimental data can be achieved. The neutrino mass spectrum is predicted to be of the inverted hierarchy and the second octant of θ23 is preferred. We suggest the modified democratic mixing, which is obtained by permuting the second and the third rows of the democratic mixing matrix, should be a good first order approximation to understanding sizable θ13 and the first octant of θ23. The constraints on the model from the electroweak precision measurements are discussed. Furthermore, we investigate the lepton mixing patterns for all the possible residual symmetries Gν and Gl in the neutrino and charged lepton sectors, respectively. For convenience, we work in the base in which m≡mlml† is diagonal, where ml is the charged lepton mass matrix. It is easy to see that the symmetry transformation matrix Gl, which is determined by the condition Gl†mGl=m, is a diagonal and non-degenerate 3×3 phase matrix. In the case that neutrinos are Majorana particles, the light neutrino mass matrix for DC mixing is of the form mνDC=UDC*diag(m1,m2,m3)UDC†. The symmetry transformations Gi, which satisfy GiTmνDCGi=mνDC, are determined to be G1=+u1u1†-u2u2†-u3u3†, G2=-u1u1†+u2u2†-u3u3† and G3=-u1u1†-u2u2†+u3u3† besides the identity transformation, where ui is the ith column of UDC. They satisfy Gi2=1, GiGj=GjGi=Gk(i≠j≠k). Consequently the symmetry group of the neutrino mass matrix mνDC is the Klein four group K4≅Z2×Z2. Denoting the underlying family symmetry group at high energies as G, then the symmetry transformations Gl and Gi should be the elements of G. In the

Isometries, gaugings and {N} = 2 supergravity decoupling

NASA Astrophysics Data System (ADS)

Antoniadis, Ignatios; Derendinger, Jean-Pierre; Petropoulos, P. Marios; Siampos, Konstantinos

2016-11-01

We study off-shell rigid limits for the kinetic and scalar-potential terms of a single {N} = 2 hypermultiplet. In the kinetic term, these rigid limits establish relations between four-dimensional quaternion-Kähler and hyper-Kähler target spaces with symmetry. The scalar potential is obtained by gauging the graviphoton along an isometry of the quaternion-Kähler space. The rigid limits unveil two distinct cases. A rigid {N} = 2 theory on Minkowski or on AdS4 spacetime, depending on whether the isometry is translational or rotational respectively. We apply these results to the quaternion-Kähler space with Heisenberg ⋉ U(1) isometry, which describes the universal hypermultiplet at type-II string one-loop.

Holographic Symmetries and Generalized Order Parameters for Topological Matter

NASA Astrophysics Data System (ADS)

Cobanera, Emilio; Ortiz, Gerardo; Nussinov, Zohar

2013-03-01

We introduce a universally applicable method, based on the bond-algebraic theory of dualities, to search for generalized order parameters in a wide variety of non-Landau systems, including topologically ordered matter. To this end we introduce the key notion of holographic symmetry. It reflects situations in which global symmetries become exact boundary symmetries under a duality mapping. Holographic symmetries are naturally related to edge modes and localization. The utility of our approach is illustrated by presenting a systematic derivation of generalized order parameters for pure and matter-coupled Abelian gauge theories and (extended) toric codes. Also we introduce a many-body extension of the Kitaev wire, the gauged Kitaev wire, and exploit holographic symmetries and dualities to describe its phase diagram, generalized order parameter, and edge states. [arXiv:1211.0564] This work was supported by the Dutch Science Foundation NWO/FOM and an ERC Advanced Investigator grant, and, in part, under grants No. NSF PHY11-25915 and CMMT 1106293.

An A{sub r} threesome: Matrix models, 2d conformal field theories, and 4dN=2 gauge theories

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schiappa, Ricardo; Wyllard, Niclas

We explore the connections between three classes of theories: A{sub r} quiver matrix models, d=2 conformal A{sub r} Toda field theories, and d=4N=2 supersymmetric conformal A{sub r} quiver gauge theories. In particular, we analyze the quiver matrix models recently introduced by Dijkgraaf and Vafa (unpublished) and make detailed comparisons with the corresponding quantities in the Toda field theories and the N=2 quiver gauge theories. We also make a speculative proposal for how the matrix models should be modified in order for them to reproduce the instanton partition functions in quiver gauge theories in five dimensions.

Generic first-order phase transitions between isotropic and orientational phases with polyhedral symmetries

NASA Astrophysics Data System (ADS)

Liu, Ke; Greitemann, Jonas; Pollet, Lode

2018-01-01

Polyhedral nematics are examples of exotic orientational phases that possess a complex internal symmetry, representing highly nontrivial ways of rotational symmetry breaking, and are subject to current experimental pursuits in colloidal and molecular systems. The classification of these phases has been known for a long time; however, their transitions to the disordered isotropic liquid phase remain largely unexplored, except for a few symmetries. In this work, we utilize a recently introduced non-Abelian gauge theory to explore the nature of the underlying nematic-isotropic transition for all three-dimensional polyhedral nematics. The gauge theory can readily be applied to nematic phases with an arbitrary point-group symmetry, including those where traditional Landau methods and the associated lattice models may become too involved to implement owing to a prohibitive order-parameter tensor of high rank or (the absence of) mirror symmetries. By means of exhaustive Monte Carlo simulations, we find that the nematic-isotropic transition is generically first-order for all polyhedral symmetries. Moreover, we show that this universal result is fully consistent with our expectation from a renormalization group approach, as well as with other lattice models for symmetries already studied in the literature. We argue that extreme fine tuning is required to promote those transitions to second-order ones. We also comment on the nature of phase transitions breaking the O(3 ) symmetry in general cases.

Quantum mechanics of Klein-Gordon fields I: Hilbert Space, localized states, and chiral symmetry

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mostafazadeh, A.; Zamani, F.

2006-09-15

We derive an explicit manifestly covariant expression for the most general positive-definite and Lorentz-invariant inner product on the space of solutions of the Klein-Gordon equation. This expression involves a one-parameter family of conserved current densities J{sub a}{sup {mu}}, with a-bar (-1,1), that are analogous to the chiral current density for spin half fields. The conservation of J{sub a}{sup {mu}} is related to a global gauge symmetry of the Klein-Gordon fields whose gauge group is U(1) for rational a and the multiplicative group of positive real numbers for irrational a. We show that the associated gauge symmetry is responsible for themore » conservation of the total probability of the localization of the field in space. This provides a simple resolution of the paradoxical situation resulting from the fact that the probability current density for free scalar fields is neither covariant nor conserved. Furthermore, we discuss the implications of our approach for free real scalar fields offering a direct proof of the uniqueness of the relativistically invariant positive-definite inner product on the space of real Klein-Gordon fields. We also explore an extension of our results to scalar fields minimally coupled to an electromagnetic field.« less

U.S., U.S.S.R. Marine Expedition

NASA Astrophysics Data System (ADS)

Wainger, Lisa A.

An historic expedition involving U.S. and U.S.S.R. scientists may open a new era of cooperation in marine research. A University of California, San Diego/Scripps Institution of Oceanography ship carrying a team that includes two Soviet scientists is on an expedition that will take the R/V Thomas Washington into the Exclusive Economic Zone (EEZ) of the U.S.S.R. For the first time in a decade a U.S. research vessel has been given permission to operate in the Soviet Union's EEZ, according to Department of State representative Tom Cocke, who worked with Scripps on this project. The ship will also operate in the U.S. EEZ and international waters.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Oegetbil, O.

After reviewing the existing results we give an extensive analysis of the critical points of the potentials of the gauged N=2 Yang-Mills/Einstein supergravity theories coupled to tensor multiplets and hypermultiplets. Our analysis includes all the possible gaugings of all N=2 Maxwell-Einstein supergravity theories whose scalar manifolds are symmetric spaces. In general, the scalar potential gets contributions from R-symmetry gauging, tensor couplings, and hypercouplings. We show that the coupling of a hypermultiplet into a theory whose potential has a nonzero value at its critical point, and gauging a compact subgroup of the hyperscalar isometry group will only rescale the value ofmore » the potential at the critical point by a positive factor, and therefore will not change the nature of an existing critical point. However this is not the case for noncompact SO(1,1) gaugings. An SO(1,1) gauging of the hyperisometry will generally lead to de Sitter vacua, which is analogous to the ground states found by simultaneously gauging SO(1,1) symmetry of the real scalar manifold with U(1){sub R} in earlier literature. SO(m,1) gaugings with m>1, which give contributions to the scalar potential only in the magical Jordan family theories, on the other hand, do not lead to de Sitter vacua. Anti-de Sitter vacua are generically obtained when the U(1){sub R} symmetry is gauged. We also show that it is possible to embed certain generic Jordan family theories into the magical Jordan family preserving the nature of the ground states. However the magical Jordan family theories have additional ground states which are not found in the generic Jordan family theories.« less

Symmetry and defects in rhombohedral single-crystalline Na0.5Bi0.5TiO3

NASA Astrophysics Data System (ADS)

Beanland, Richard; Thomas, Pam A.

2014-05-01

Recent work has indicated that the symmetry of the lead-free piezoelectric perovskite Na0.5Bi0.5TiO3 can be changed from monoclinic to rhombohedral through the application of an electric field, which may have implications for the study and design of piezoelectric materials close to a morphotropic phase boundary. We have examined high-quality, single-crystal Na0.5Bi0.5TiO3 using transmission electron microscopy and have used digital electron diffraction to observe the symmetry of defect-free regions of material on length scales of a few nanometers. This unequivocally demonstrates that the material is rhombohedral with space group R3c on this length scale. We find that a model that allows disordered displacements of Bi atoms from their nominal sites in the R3c symmetry, while retaining this symmetry on average, gives a very significant improvement in fit to simulations. We use conventional transmission electron microscopy to enumerate the different types of defects that are observed in other regions of the crystal and find a complex microstructure of antiphase boundaries, domain walls, and tetragonal platelets. Their interaction leads to the formation of very high densities of nanotwins. We show that these are expected to have a variable monoclinic Cc symmetry that is driven by the constraint of continuity of the crystal across a domain wall.

2d affine XY-spin model/4d gauge theory duality and deconfinement

NASA Astrophysics Data System (ADS)

Anber, Mohamed M.; Poppitz, Erich; Ünsal, Mithat

2012-04-01

We introduce a duality between two-dimensional XY-spin models with symmetry-breaking perturbations and certain four-dimensional SU(2) and SU(2)/ {{Z}_2} gauge theories, compactified on a small spatial circle {{R}^{{^{{{1},{2}}}}}} × {{S}^{{^{{1}}}}} , and considered at temperatures near the deconfinement transition. In a Euclidean set up, the theory is defined on {{R}^{{^{{2}}}}} × {{T}^{{^{{2}}}}} . Similarly, thermal gauge theories of higher rank are dual to new families of "affine" XY-spin models with perturbations. For rank two, these are related to models used to describe the melting of a 2d crystal with a triangular lattice. The connection is made through a multi-component electric-magnetic Coulomb gas representation for both systems. Perturbations in the spin system map to topological defects in the gauge theory, such as monopole-instantons or magnetic bions, and the vortices in the spin system map to the electrically charged W-bosons in field theory (or vice versa, depending on the duality frame). The duality permits one to use the two-dimensional technology of spin systems to study the thermal deconfinement and discrete chiral transitions in four-dimensional SU( N c ) gauge theories with n f ≥1 adjoint Weyl fermions.

Bose-Einstein condensation, spontaneous symmetry breaking, and gauge theories

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kapusta, J.I.

1981-07-15

Bosonic chemical potentials for a variety of relativistic field theories are introduced via the methods of functional integrals with the aim of studying the relationship between Bose-Einstein condensation and spontaneous symmetry breaking. The models studied include the noninteracting and the self-interacting charged scalar field, scalar electrodynamics and the Higgs model, and the Weinberg-Salam model. In general the chemical potential acts as an effective symmetry-breaking parameter although the phase diagrams for the two cases (m/sup 2/<0 and m/sup 2/>0) look very different. It is found that the symmetry-restoring temperature in the Weinberg-Salam model increases with increasing electric charge density. Finally, themore » analysis of Jakobsen, Kon, and Segal of a conserved isotropic total angular momentum for the cosmic background radiation is shown to be erroneous.« less

PH Tester Gauge Repeatability and Reproducibility Study for WO3 Nanostructure Hydrothermal Growth Process

NASA Astrophysics Data System (ADS)

Abd Rashid, Amirul; Hayati Saad, Nor; Bien Chia Sheng, Daniel; Yee, Lee Wai

2014-06-01

PH value is one of the important variables for tungsten trioxide (WO3) nanostructure hydrothermal synthesis process. The morphology of the synthesized nanostructure can be properly controlled by measuring and controlling the pH value of the solution used in this facile synthesis route. Therefore, it is very crucial to ensure the gauge used for pH measurement is reliable in order to achieve the expected result. In this study, gauge repeatability and reproducibility (GR&R) method was used to assess the repeatability and reproducibility of the pH tester. Based on ANOVA method, the design of experimental metrics as well as the result of the experiment was analyzed using Minitab software. It was found that the initial GR&R value for the tester was at 17.55 % which considered as acceptable. To further improve the GR&R level, a new pH measuring procedure was introduced. With the new procedure, the GR&R value was able to be reduced to 2.05%, which means the tester is statistically very ideal to measure the pH of the solution prepared for WO3 hydrothermal synthesis process.

Area-Preserving Diffeomorphisms, W∞ and { U}q [sl(2)] in Chern-Simons Theory and the Quantum Hall System

NASA Astrophysics Data System (ADS)

Kogan, Ian I.

We discuss a quantum { U}q [sl(2)] symmetry in the Landau problem, which naturally arises due to the relation between { U}q [sl(2)] and the group of magnetic translations. The latter is connected with W∞ and area-preserving (symplectic) diffeomorphisms which are the canonical transformations in the two-dimensional phase space. We shall discuss the hidden quantum symmetry in a 2 + 1 gauge theory with the Chern-Simons term and in a quantum Hall system, which are both connected with the Landau problem.

Gauge theory for finite-dimensional dynamical systems.

PubMed

Gurfil, Pini

2007-06-01

Gauge theory is a well-established concept in quantum physics, electrodynamics, and cosmology. This concept has recently proliferated into new areas, such as mechanics and astrodynamics. In this paper, we discuss a few applications of gauge theory in finite-dimensional dynamical systems. We focus on the concept of rescriptive gauge symmetry, which is, in essence, rescaling of an independent variable. We show that a simple gauge transformation of multiple harmonic oscillators driven by chaotic processes can render an apparently "disordered" flow into a regular dynamical process, and that there exists a strong connection between gauge transformations and reduction theory of ordinary differential equations. Throughout the discussion, we demonstrate the main ideas by considering examples from diverse fields, including quantum mechanics, chemistry, rigid-body dynamics, and information theory.

Global symmetries and renormalizability of Lee-Wick theories

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chivukula, R. Sekhar; Farzinnia, Arsham; Foadi, Roshan

2010-08-01

In this paper we discuss the global symmetries and the renormalizability of Lee-Wick (LW) scalar QED. In particular, in the ''auxiliary-field'' formalism we identify softly broken SO(1,1) global symmetries of the theory. We introduce SO(1,1) invariant gauge-fixing conditions that allow us to show in the auxiliary-field formalism directly that the number of superficially divergent amplitudes in a LW Abelian gauge theory is finite. To illustrate the renormalizability of the theory, we explicitly carry out the one-loop renormalization program in LW scalar QED and demonstrate how the counterterms required are constrained by the joint conditions of gauge and SO(1,1) invariance. Wemore » also compute the one-loop beta functions in LW scalar QED and contrast them with those of ordinary scalar QED.« less

Spin Triplet Nematic Pairing Symmetry and Superconducting Double Transition in U1-xThxBe13

NASA Astrophysics Data System (ADS)

Machida, Kazushige

2018-03-01

Motivated by a recent experiment on U1-xThxBe13 with x = 3%, we develop a theory to narrow down the possible pair symmetry to consistently describe the double transition utilizing various theoretical tools, including group theory and Ginzburg-Landau theory. It is explained in terms of the two-dimensional representation Eu with spin triplet. Symmetry breaking causes the degenerate Tc to split into two. The low-temperature phase is identified as the cyclic p wave: d(k) = \\hat{x}kx + ɛ \\hat{y}ky + ɛ 2\\hat{z}kz with ɛ3 = 1, whereas the biaxial nematic phase: d(k) = √{3} (\\hat{x}kx - \\hat{y}ky) is the high-temperature one. This allows us to simultaneously identify the uniaxial nematic phase: d(k) = 2\\hat{z}kz - \\hat{x}kx - \\hat{y}ky for UBe13, which spontaneously breaks the cubic symmetry of the system. Those pair functions are fully consistent with this description and existing data. We comment on the accidental scenario in addition to this degeneracy scenario and the intriguing topological nature hidden in this long-known material.

Confronting Seiberg's duality with r duality in N=1 supersymmetric QCD

NASA Astrophysics Data System (ADS)

Shifman, M.; Yung, A.

2012-09-01

Systematizing our results on r duality obtained previously we focus on comparing r duality with the generalized Seiberg duality in the r vacua of N=2 and N=1 super-Yang-Mills theories with the U(N) gauge group and Nf matter flavors (Nf>N). The number of condensed (s)quarks r is assumed to be in the interval (2)/(3)Nfr dual theory with the U(Nf-r) gauge group and Nf light quarklike dyon flavors. Dyon condensation leads to confinement of monopoles, defying a naive expectation of quark confinement. The quarks and gauge bosons of the original theory are in an “instead-of-confinement” phase. The r and Seiberg dualities are demonstrated to coincide in the r=N vacua. In the (2)/(3)Nf<rr-dual model is at weak coupling. Thus, we can speak of triality. Seiberg’s dual solution at weak coupling reappears again at r3)Nf.

Majorana dark matter with B+L gauge symmetry

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chao, Wei; Guo, Huai-Ke; Zhang, Yongchao

Here, we present a new model that extends the Standard Model (SM) with the local B + L symmetry, and point out that the lightest new fermion, introduced to cancel anomalies and stabilized automatically by the B + L symmetry, can serve as the cold dark matter candidate. We also study constraints on the model from Higgs measurements, electroweak precision measurements as well as the relic density and direct detections of the dark matter. Our numerical results reveal that the pseudo-vector coupling of with Z and the Yukawa coupling with the SM Higgs are highly constrained by the latest resultsmore » of LUX, while there are viable parameter space that could satisfy all the constraints and give testable predictions.« less

Majorana dark matter with B+L gauge symmetry

DOE PAGES

Chao, Wei; Guo, Huai-Ke; Zhang, Yongchao

2017-04-07

Here, we present a new model that extends the Standard Model (SM) with the local B + L symmetry, and point out that the lightest new fermion, introduced to cancel anomalies and stabilized automatically by the B + L symmetry, can serve as the cold dark matter candidate. We also study constraints on the model from Higgs measurements, electroweak precision measurements as well as the relic density and direct detections of the dark matter. Our numerical results reveal that the pseudo-vector coupling of with Z and the Yukawa coupling with the SM Higgs are highly constrained by the latest resultsmore » of LUX, while there are viable parameter space that could satisfy all the constraints and give testable predictions.« less

Three-Triplet Model with Double SU(3) Symmetry

DOE R&D Accomplishments Database

Han, M. Y.; Nambu, Y.

1965-01-01

With a view to avoiding some of the kinematical and dynamical difficulties involved in the single triplet quark model, a model for the low lying baryons and mesons based on three triplets with integral charges is proposed, somewhat similar to the two-triplet model introduced earlier by one of us (Y. N.). It is shown that in a U(3) scheme of triplets with integral charges, one is naturally led to three triplets located symmetrically about the origin of I{sub 3} - Y diagram under the constraint that Nishijima-Gell-Mann relation remains intact. A double SU(3) symmetry scheme is proposed in which the large mass splittings between different representations are ascribed to one of the SU(3), while the other SU(3) is the usual one for the mass splittings within a representation of the first SU(3).

The classical dynamic symmetry for the U(1) -Kepler problems

NASA Astrophysics Data System (ADS)

Bouarroudj, Sofiane; Meng, Guowu

2018-01-01

For the Jordan algebra of hermitian matrices of order n ≥ 2, we let X be its submanifold consisting of rank-one semi-positive definite elements. The composition of the cotangent bundle map πX: T∗ X → X with the canonical map X → CP n - 1 (i.e., the map that sends a given hermitian matrix to its column space), pulls back the Kähler form of the Fubini-Study metric on CP n - 1 to a real closed differential two-form ωK on T∗ X. Let ωX be the canonical symplectic form on T∗ X and μ a real number. A standard fact says that ωμ ≔ωX + 2 μωK turns T∗ X into a symplectic manifold, hence a Poisson manifold with Poisson bracket {,}μ. In this article we exhibit a Poisson realization of the simple real Lie algebra su(n , n) on the Poisson manifold (T∗ X ,{,}μ) , i.e., a Lie algebra homomorphism from su(n , n) to (C∞(T∗ X , R) ,{,}μ). Consequently one obtains the Laplace-Runge-Lenz vector for the classical U(1) -Kepler problem of level n and magnetic charge μ. Since the McIntosh-Cisneros-Zwanziger-Kepler problems (MICZ-Kepler Problems) are the U(1) -Kepler problems of level 2, the work presented here is a direct generalization of the work by A. Barut and G. Bornzin (1971) on the classical dynamic symmetry for the MICZ-Kepler problems.

Collapse of the Ia{bar 3}d cubic symmetry by uniaxial stretching of a double-gyroid block copolymer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sakurai, Shinichi; Isobe, Daisuke; Okamoto, Shigeru

2001-06-01

We report an experimental observation of collapse of the Ia{bar 3}d symmetry by stretching of an elastomeric block copolymer that forms a double-gyroid (DG) microdomain structure. Some new diffraction spots were observed for a deformed DG structure. These spots were assigned to {l_brace}110{r_brace} and {l_brace}200{r_brace} reflections. For the Ia{bar 3}d symmetry, these reflections are prohibited by the extinction rule and therefore none of them appeared for the sample before deformation. Appearance of these reflections indicates breakdown of the extinction rule and can be explained as a result of collapse of the symmetry of glide when three-dimensional DG networks are partiallymore » ruptured upon stretching.« less

The role of Weyl symmetry in hydrodynamics

NASA Astrophysics Data System (ADS)

Diles, Saulo

2018-04-01

This article is dedicated to the analysis of Weyl symmetry in the context of relativistic hydrodynamics. Here is discussed how this symmetry is properly implemented using the prescription of minimal coupling: ∂ → ∂ + ωA. It is shown that this prescription has no problem to deal with curvature since it gives the correct expressions for the commutator of covariant derivatives. In hydrodynamics, Weyl gauge connection emerges from the degrees of freedom of the fluid: it is a combination of the expansion and entropy gradient. The remaining degrees of freedom, shear, vorticity and the metric tensor, are see in this context as charged fields under the Weyl gauge connection. The gauge nature of the connection provides natural dynamics to it via equations of motion analogous to the Maxwell equations for electromagnetism. As a consequence, a charge for the Weyl connection is defined and the notion of local charge is analyzed generating the conservation law for the Weyl charge.

Importance of Broken Gauge Symmetry in Addressing Three, Key, Unanswered Questions Posed by Low Nuclear Reactions (LENR's)

NASA Astrophysics Data System (ADS)

Chubb, Scott

2003-03-01

Three, Key, Unanswered Questions posed by LENR's are: 1. How do we explain the lack of high energy particles (HEP's)? 2. Can we understand and prioritize the way coupling can occur between nuclear- and atomic- lengthscales, and 3. What are the roles of Surface-Like (SL), as opposed to Bulk-Like (BL), processes in triggering nuclear phenomena. One important source of confusion associated with each of these questions is the common perception that the quantum mechanical phases of different particles are not correlated with each other. When the momenta p of interacting particles is large, and reactions occur rapidly (between HEP's, for example), this is a valid assumption. But when the relative difference in p becomes vanishingly small, between one charge, and many others, as a result of implicit electromagnetic coupling, each charge can share a common phase, relative to the others, modulo 2nπ, where n is an integer, even when outside forces are introduced. The associated forms of broken gauge symmetry, distinguish BL from SL phenomena, at room temperature, also explain super- and normal- conductivity in solids, and can be used to address the Three, Key, Unanswered Questions posed by LENR's.

Continuous spin fields of mixed-symmetry type

NASA Astrophysics Data System (ADS)

Alkalaev, Konstantin; Grigoriev, Maxim

2018-03-01

We propose a description of continuous spin massless fields of mixed-symmetry type in Minkowski space at the level of equations of motion. It is based on the appropriately modified version of the constrained system originally used to describe massless bosonic fields of mixed-symmetry type. The description is shown to produce generalized versions of triplet, metric-like, and light-cone formulations. In particular, for scalar continuous spin fields we reproduce the Bekaert-Mourad formulation and the Schuster-Toro formulation. Because a continuous spin system inevitably involves infinite number of fields, specification of the allowed class of field configurations becomes a part of its definition. We show that the naive choice leads to an empty system and propose a suitable class resulting in the correct degrees of freedom. We also demonstrate that the gauge symmetries present in the formulation are all Stueckelberg-like so that the continuous spin system is not a genuine gauge theory.

Electron nematic fluid in a strained S r3R u2O7 film

NASA Astrophysics Data System (ADS)

Marshall, Patrick B.; Ahadi, Kaveh; Kim, Honggyu; Stemmer, Susanne

2018-04-01

S r3R u2O7 belongs to the family of layered strontium ruthenates and exhibits a range of unusual emergent properties, such as electron nematic behavior and metamagnetism. Here, we show that epitaxial film strain significantly modifies these phenomena. In particular, we observe enhanced magnetic interactions and an electron nematic phase that extends to much higher temperatures and over a larger magnetic-field range than in bulk single crystals. Furthermore, the films show an unusual anisotropic non-Fermi-liquid behavior that is controlled by the direction of the applied magnetic field. At high magnetic fields, the metamagnetic transition to a ferromagnetic phase recovers isotropic Fermi-liquid behavior. The results support the interpretation that these phenomena are linked to the special features of the Fermi surface, which can be tuned by both film strain and an applied magnetic field.

Augmented superfield approach to gauge-invariant massive 2-form theory

NASA Astrophysics Data System (ADS)

Kumar, R.; Krishna, S.

2017-06-01

We discuss the complete sets of the off-shell nilpotent (i.e. s^2_{(a)b} = 0) and absolutely anticommuting (i.e. s_b s_{ab} + s_{ab} s_b = 0) Becchi-Rouet-Stora-Tyutin (BRST) (s_b) and anti-BRST (s_{ab}) symmetries for the (3+1)-dimensional (4D) gauge-invariant massive 2-form theory within the framework of an augmented superfield approach to the BRST formalism. In this formalism, we obtain the coupled (but equivalent) Lagrangian densities which respect both BRST and anti-BRST symmetries on the constrained hypersurface defined by the Curci-Ferrari type conditions. The absolute anticommutativity property of the (anti-) BRST transformations (and corresponding generators) is ensured by the existence of the Curci-Ferrari type conditions which emerge very naturally in this formalism. Furthermore, the gauge-invariant restriction plays a decisive role in deriving the proper (anti-) BRST transformations for the Stückelberg-like vector field.

Soft thermal contributions to 3-loop gauge coupling

NASA Astrophysics Data System (ADS)

Laine, M.; Schicho, P.; Schröder, Y.

2018-05-01

We analyze 3-loop contributions to the gauge coupling felt by ultrasoft ("magnetostatic") modes in hot Yang-Mills theory. So-called soft/hard terms, originating from dimension-six operators within the soft effective theory, are shown to cancel 1097/1098 of the IR divergence found in a recent determination of the hard 3-loop contribution to the soft gauge coupling. The remaining 1/1098 originates from ultrasoft/hard contributions, induced by dimension-six operators in the ultrasoft effective theory. Soft 3-loop contributions are likewise computed, and are found to be IR divergent, rendering the ultrasoft gauge coupling non-perturbative at relative order O({α}s^{3/2}) . We elaborate on the implications of these findings for effective theory studies of physical observables in thermal QCD.

Localization of U(1) gauge vector field on flat branes with five-dimension (asymptotic) AdS5 spacetime

NASA Astrophysics Data System (ADS)

Zhao, Zhen-Hua; Xie, Qun-Ying

2018-05-01

In order to localize U(1) gauge vector field on Randall-Sundrum-like braneworld model with infinite extra dimension, we propose a new kind of non-minimal coupling between the U(1) gauge field and the gravity. We propose three kinds of coupling methods and they all support the localization of zero mode. In addition, one of them can support the localization of massive modes. Moreover, the massive tachyonic modes can be excluded. And our method can be used not only in the thin braneword models but also in the thick ones.

Cobimaximal lepton mixing from soft symmetry breaking

NASA Astrophysics Data System (ADS)

Grimus, W.; Lavoura, L.

2017-11-01

Cobimaximal lepton mixing, i.e.θ23 = 45 ° and δ = ± 90 ° in the lepton mixing matrix V, arises as a consequence of SV =V* P, where S is the permutation matrix that interchanges the second and third rows of V and P is a diagonal matrix of phase factors. We prove that any such V may be written in the form V = URP, where U is any predefined unitary matrix satisfying SU =U*, R is an orthogonal, i.e. real, matrix, and P is a diagonal matrix satisfying P2 = P. Using this theorem, we demonstrate the equivalence of two ways of constructing models for cobimaximal mixing-one way that uses a standard CP symmetry and a different way that uses a CP symmetry including μ-τ interchange. We also present two simple seesaw models to illustrate this equivalence; those models have, in addition to the CP symmetry, flavour symmetries broken softly by the Majorana mass terms of the right-handed neutrino singlets. Since each of the two models needs four scalar doublets, we investigate how to accommodate the Standard Model Higgs particle in them.

Gauge theory for finite-dimensional dynamical systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gurfil, Pini

2007-06-15

Gauge theory is a well-established concept in quantum physics, electrodynamics, and cosmology. This concept has recently proliferated into new areas, such as mechanics and astrodynamics. In this paper, we discuss a few applications of gauge theory in finite-dimensional dynamical systems. We focus on the concept of rescriptive gauge symmetry, which is, in essence, rescaling of an independent variable. We show that a simple gauge transformation of multiple harmonic oscillators driven by chaotic processes can render an apparently ''disordered'' flow into a regular dynamical process, and that there exists a strong connection between gauge transformations and reduction theory of ordinary differentialmore » equations. Throughout the discussion, we demonstrate the main ideas by considering examples from diverse fields, including quantum mechanics, chemistry, rigid-body dynamics, and information theory.« less

Cosmology from a gauge induced gravity

NASA Astrophysics Data System (ADS)

Falciano, F. T.; Sadovski, G.; Sobreiro, R. F.; Tomaz, A. A.

2017-09-01

The main goal of the present work is to analyze the cosmological scenario of the induced gravity theory developed in previous works. Such a theory consists on a Yang-Mills theory in a four-dimensional Euclidian spacetime with { SO}(m,n) such that m+n=5 and m\\in {0,1,2} as its gauge group. This theory undergoes a dynamical gauge symmetry breaking via an Inönü-Wigner contraction in its infrared sector. As a consequence, the { SO}(m,n) algebra is deformed into a Lorentz algebra with the emergency of the local Lorentz symmetries and the gauge fields being identified with a vierbein and a spin connection. As a result, gravity is described as an effective Einstein-Cartan-like theory with ultraviolet correction terms and a propagating torsion field. We show that the cosmological model associated with this effective theory has three different regimes. In particular, the high curvature regime presents a de Sitter phase which tends towards a Λ CDM model. We argue that { SO}(m,n) induced gravities are promising effective theories to describe the early phase of the universe.

M2-brane surface operators and gauge theory dualities in Toda

NASA Astrophysics Data System (ADS)

Gomis, Jaume; Le Floch, Bruno

2016-04-01

We give a microscopic two dimensional {N} = (2, 2) gauge theory description of arbitrary M2-branes ending on N f M5-branes wrapping a punctured Riemann surface. These realize surface operators in four dimensional {N} = 2 field theories. We show that the expectation value of these surface operators on the sphere is captured by a Toda CFT correlation function in the presence of an additional degenerate vertex operator labelled by a representation {R} of SU( N f ), which also labels M2-branes ending on M5-branes. We prove that symmetries of Toda CFT correlators provide a geometric realization of dualities between two dimensional gauge theories, including {N} = (2, 2) analogues of Seiberg and Kutasov-Schwimmer dualities. As a bonus, we find new explicit conformal blocks, braiding matrices, and fusion rules in Toda CFT.

Magnetically charged calorons with non-trivial holonomy

NASA Astrophysics Data System (ADS)

Kato, Takumi; Nakamula, Atsushi; Takesue, Koki

2018-06-01

Instantons in pure Yang-Mills theories on partially periodic space R^3× {S}^1 are usually called calorons. The background periodicity brings on characteristic features of calorons such as non-trivial holonomy, which plays an essential role for confinement/deconfinement transition in pure Yang-Mills gauge theory. For the case of gauge group SU(2), calorons can be interpreted as composite objects of two constituent "monopoles" with opposite magnetic charges. There are often the cases that the two monopole charges are unbalanced so that the calorons possess net magnetic charge in R3. In this paper, we consider several mechanism how such net magnetic charges appear for certain types of calorons through the ADHM/Nahm construction with explicit examples. In particular, we construct analytically the gauge configuration of the (2 , 1)-caloron with U(1)-symmetry, which has intrinsically magnetic charge.

Nilpotent symmetries in supergroup field cosmology

NASA Astrophysics Data System (ADS)

Upadhyay, Sudhaker

2015-06-01

In this paper, we study the gauge invariance of the third quantized supergroup field cosmology which is a model for multiverse. Further, we propose both the infinitesimal (usual) as well as the finite superfield-dependent BRST symmetry transformations which leave the effective theory invariant. The effects of finite superfield-dependent BRST transformations on the path integral (so-called void functional in the case of third quantization) are implemented. Within the finite superfield-dependent BRST formulation, the finite superfield-dependent BRST transformations with specific parameter switch the void functional from one gauge to another. We establish this result for the most general gauge with the help of explicit calculations which holds for all possible sets of gauge choices at both the classical and the quantum levels.

Charmless B→PP decays using flavor SU(3) symmetry

NASA Astrophysics Data System (ADS)

Chiang, Cheng-Wei; Gronau, Michael; Rosner, Jonathan L.; Suprun, Denis A.

2004-08-01

The decays of B mesons to a pair of charmless pseudoscalar (P) mesons are analyzed within a framework of flavor SU(3). Symmetry breaking is taken into account in tree (T) amplitudes through ratios of decay constants; exact SU(3) is assumed elsewhere. Acceptable fits to B→ππ and B→Kπ branching ratios and CP asymmetries are obtained with tree, color-suppressed (C), penguin (P), and electroweak penguin (PEW) amplitudes. Crucial additional terms for describing processes involving η and η' include a large flavor-singlet penguin amplitude (S) as proposed earlier and a penguin amplitude Ptu associated with intermediate t and u quarks. For the B+→π+η' mode a term Stu associated with intermediate t and u quarks also may be needed. Values of the weak phase γ are obtained consistent with an earlier analysis of B→VP decays, where V denotes a vector meson, and with other analyses of CKM parameters.

Spontaneous parity violation and SUSY strong gauge theory

NASA Astrophysics Data System (ADS)

Haba, Naoyuki; Ohki, Hiroshi

2012-07-01

We suggest simple models of spontaneous parity violation in supersymmetric strong gauge theory. We focus on left-right symmetric model and investigate vacuum with spontaneous parity violation. Non-perturbative effects are calculable in supersymmetric gauge theory, and we suggest new models. Our models show confinement, so that we try to understand them by using a dual description of the theory. The left-right symmetry breaking and electroweak symmetry breaking are simultaneously occurred with the suitable energy scale hierarchy. This structure has several advantages compared to the MSSM. The scale of the Higgs mass (left-right breaking scale) and that of VEVs are different, so the SUSY little hierarchy problems are absent. The second model also induces spontaneous supersymmetry breaking [1].

Non-Abelian string and particle braiding in topological order: Modular SL (3 ,Z ) representation and (3 +1 ) -dimensional twisted gauge theory

NASA Astrophysics Data System (ADS)

Wang, Juven C.; Wen, Xiao-Gang

2015-01-01

String and particle braiding statistics are examined in a class of topological orders described by discrete gauge theories with a gauge group G and a 4-cocycle twist ω4 of G 's cohomology group H4(G ,R /Z ) in three-dimensional space and one-dimensional time (3 +1 D ) . We establish the topological spin and the spin-statistics relation for the closed strings and their multistring braiding statistics. The 3 +1 D twisted gauge theory can be characterized by a representation of a modular transformation group, SL (3 ,Z ) . We express the SL (3 ,Z ) generators Sx y z and Tx y in terms of the gauge group G and the 4-cocycle ω4. As we compactify one of the spatial directions z into a compact circle with a gauge flux b inserted, we can use the generators Sx y and Tx y of an SL (2 ,Z ) subgroup to study the dimensional reduction of the 3D topological order C3 D to a direct sum of degenerate states of 2D topological orders Cb2 D in different flux b sectors: C3 D=⊕bCb2 D . The 2D topological orders Cb2 D are described by 2D gauge theories of the group G twisted by the 3-cocycle ω3 (b ), dimensionally reduced from the 4-cocycle ω4. We show that the SL (2 ,Z ) generators, Sx y and Tx y, fully encode a particular type of three-string braiding statistics with a pattern that is the connected sum of two Hopf links. With certain 4-cocycle twists, we discover that, by threading a third string through two-string unlink into a three-string Hopf-link configuration, Abelian two-string braiding statistics is promoted to non-Abelian three-string braiding statistics.

Symmetries of hyper-Kähler (or Poisson gauge field) hierarchy

NASA Astrophysics Data System (ADS)

Takasaki, K.

1990-08-01

Symmetry properties of the space of complex (or formal) hyper-Kähler metrics are studied in the language of hyper-Kähler hierarchies. The construction of finite symmetries is analogous to the theory of Riemann-Hilbert transformations, loop group elements now taking values in a (pseudo-) group of canonical transformations of a simplectic manifold. In spite of their highly nonlinear and involved nature, infinitesimal expressions of these symmetries are shown to have a rather simple form. These infinitesimal transformations are extended to the Plebanski key functions to give rise to a nonlinear realization of a Poisson loop algebra. The Poisson algebra structure turns out to originate in a contact structure behind a set of symplectic structures inherent in the hyper-Kähler hierarchy. Possible relations to membrane theory are briefly discussed.

Radial symmetry in a chimeric glutamate receptor pore

NASA Astrophysics Data System (ADS)

Wilding, Timothy J.; Lopez, Melany N.; Huettner, James E.

2014-02-01

Ionotropic glutamate receptors comprise two conformationally different A/C and B/D subunit pairs. Closed channels exhibit fourfold radial symmetry in the transmembrane domain (TMD) but transition to twofold dimer-of-dimers symmetry for extracellular ligand binding and N-terminal domains. Here, to evaluate symmetry in open pores we analysed interaction between the Q/R editing site near the pore loop apex and the transmembrane M3 helix of kainate receptor subunit GluK2. Chimeric subunits that combined the GluK2 TMD with extracellular segments from NMDA receptors, which are obligate heteromers, yielded channels made up of A/C and B/D subunit pairs with distinct substitutions along M3 and/or Q/R site editing status, in an otherwise identical homotetrameric TMD. Our results indicate that Q/R site interaction with M3 occurs within individual subunits and is essentially the same for both A/C and B/D subunit conformations, suggesting that fourfold pore symmetry persists in the open state.

Evidence of in-plane ferromagnetic order probed by planar Hall effect in the geometry-confined ruthenate S r4R u3O10

NASA Astrophysics Data System (ADS)

Liu, Yan; Yang, Jiyong; Wang, Weike; Du, Haifeng; Ning, Wei; Ling, Langsheng; Tong, Wei; Qu, Zhe; Cao, Gang; Zhang, Yuheng; Tian, Mingliang

2017-04-01

The magnetic structure in the strongly correlated ruthenate S r4R u3O10 has been debated for a long time and still remains elusive. Here, we perform a systematically planar Hall effect study on a single-crystalline S r4R u3O10 nanostripe with a thickness of less than 100 nm. Large sharp switching behavior is observed in the planar Hall resistance, unambiguously indicating a strong anisotropic in-plane ferromagnetic order in the nanostripe, which is in contrast to the bulk system. Temperature-dependent evolution of the in-plane magnetism reveals that the in-plane spin order transforms from a single-domain state below a Curie temperature TC into a multidomain state below a critical temperature TM, probably due to the inherent strong spin-orbit coupling driven reconfiguration of spins between the c axis and the a b plane.

Accidental symmetries and massless quarks in the economical 3-3-1 model

DOE Office of Scientific and Technical Information (OSTI.GOV)

Montero, J. C.; Sánchez–Vega, B. L.

In the framework of a 3-3-1 model with a minimal scalar sector, known as the economical 3-3-1 model, we study its capabilities of generating realistic quark masses. After a detailed study of the symmetries of the model, before and after the spontaneous symmetry breaking, we find a remaining axial symmetry that prevents some quarks from gaining mass at all orders in perturbation theory. Since this accidental symmetry is anomalous, we also consider briefly the possibility of generating their masses for nonperturbative effects. However, we find that nonperturbative effects are not enough to generate the measured masses for the three masslessmore » quarks. Hence, these results imply that the economical 3-3-1 model is not a realistic description of the electroweak interaction.« less

Center symmetry and area laws

NASA Astrophysics Data System (ADS)

Cohen, Thomas D.

2014-08-01

SU(Nc) gauge theories containing matter fields may be invariant under transformations of some subgroup of the ZNc center; the maximum such subgroup is Zp, with p depending on Nc and the representations of the various matter fields in the theory. Confining SU(Nc) gauge theories in either 3+1 or 2+1 space-time dimensions and with matter fields in any representation have string tensions for representation R given by σR=σfp/R(p -pR)g(pR(p-pR))(p -1)g(p-1) with pR=nRmod(p), where σf is the string tension for the fundamental representation, g is a positive finite function and nR is the n-ality of R. This implies that a necessary condition for a theory in this class to have an area law is invariance of the theory under a nontrivial subgroup of the center. Significantly, these results depend on p regardless of the value of Nc.

Extended spin symmetry and the standard model

NASA Astrophysics Data System (ADS)

Besprosvany, J.; Romero, R.

2010-12-01

We review unification ideas and explain the spin-extended model in this context. Its consideration is also motivated by the standard-model puzzles. With the aim of constructing a common description of discrete degrees of freedom, as spin and gauge quantum numbers, the model departs from q-bits and generalized Hilbert spaces. Physical requirements reduce the space to one that is represented by matrices. The classification of the representations is performed through Clifford algebras, with its generators associated with Lorentz and scalar symmetries. We study a reduced space with up to two spinor elements within a matrix direct product. At given dimension, the demand that Lorentz symmetry be maintained, determines the scalar symmetries, which connect to vector-and-chiral gauge-interacting fields; we review the standard-model information in each dimension. We obtain fermions and bosons, with matter fields in the fundamental representation, radiation fields in the adjoint, and scalar particles with the Higgs quantum numbers. We relate the fields' representation in such spaces to the quantum-field-theory one, and the Lagrangian. The model provides a coupling-constant definition.

Flavor gauge models below the Fermi scale

DOE PAGES

Babu, K. S.; Friedland, A.; Machado, P. A. N.; ...

2017-12-18

The mass and weak interaction eigenstates for the quarks of the third generation are very well aligned, an empirical fact for which the Standard Model offers no explanation. We explore the possibility that this alignment is due to an additional gauge symmetry in the third generation. Specifically, we construct and analyze an explicit, renormalizable model with a gauge boson,more » $X$, corresponding to the $B-L$ symmetry of the third family. Having a relatively light (in the MeV to multi-GeV range), flavor-nonuniversal gauge boson results in a variety of constraints from different sources. By systematically analyzing 20 different constraints, we identify the most sensitive probes: kaon, $B^+$, $D^+$ and Upsilon decays, $$D-\\bar{D}^0$$ mixing, atomic parity violation, and neutrino scattering and oscillations. For the new gauge coupling $$g_X$$ in the range $$(10^{-2} - 10^{-4})$$ the model is shown to be consistent with the data. Possible ways of testing the model in $b$ physics, top and $Z$ decays, direct collider production and neutrino oscillation experiments, where one can observe nonstandard matter effects, are outlined. The choice of leptons to carry the new force is ambiguous, resulting in additional phenomenological implications, such as non-universality in semileptonic bottom decays. In conclusion, the proposed framework provides interesting connections between neutrino oscillations, flavor and collider physics.« less

Flavor gauge models below the Fermi scale

DOE Office of Scientific and Technical Information (OSTI.GOV)

Babu, K. S.; Friedland, A.; Machado, P. A. N.

The mass and weak interaction eigenstates for the quarks of the third generation are very well aligned, an empirical fact for which the Standard Model offers no explanation. We explore the possibility that this alignment is due to an additional gauge symmetry in the third generation. Specifically, we construct and analyze an explicit, renormalizable model with a gauge boson,more » $X$, corresponding to the $B-L$ symmetry of the third family. Having a relatively light (in the MeV to multi-GeV range), flavor-nonuniversal gauge boson results in a variety of constraints from different sources. By systematically analyzing 20 different constraints, we identify the most sensitive probes: kaon, $B^+$, $D^+$ and Upsilon decays, $$D-\\bar{D}^0$$ mixing, atomic parity violation, and neutrino scattering and oscillations. For the new gauge coupling $$g_X$$ in the range $$(10^{-2} - 10^{-4})$$ the model is shown to be consistent with the data. Possible ways of testing the model in $b$ physics, top and $Z$ decays, direct collider production and neutrino oscillation experiments, where one can observe nonstandard matter effects, are outlined. The choice of leptons to carry the new force is ambiguous, resulting in additional phenomenological implications, such as non-universality in semileptonic bottom decays. In conclusion, the proposed framework provides interesting connections between neutrino oscillations, flavor and collider physics.« less

A New Approach to Sap Flow Measurement Using 3D Printed Gauges and Open-source Electronics

NASA Astrophysics Data System (ADS)

Ham, J. M.; Miner, G. L.; Kluitenberg, G. J.

2015-12-01

A new type of sap flow gauge was developed to measure transpiration from herbaceous plants using a modified heat pulse technique. Gauges were fabricated using 3D-printing technology and low-cost electronics to keep the materials cost under $20 (U.S.) per sensor. Each gauge consisted of small-diameter needle probes fastened to a 3D-printed frame. One needle contained a resistance heater to provide a 6 to 8 second heat pulse while the other probes measured the resultant temperature increase at two distances from the heat source. The data acquisition system for the gauges was built from a low-cost Arduino microcontroller. The system read the gauges every 10 minutes and stored the results on a SD card. Different numerical techniques were evaluated for estimating sap velocity from the heat pulse data - including analytical solutions and parameter estimation approaches . Prototype gauges were tested in the greenhouse on containerized corn and sunflower. Sap velocities measured by the gauges were compared to independent gravimetric measurements of whole plant transpiration. Results showed the system could measure daily transpiration to within 3% of the gravimetric measurements. Excellent agreement was observed when two gauges were attached the same stem. Accuracy was not affected by rapidly changing transpiration rates observed under partly cloudy conditions. The gauge-based estimates of stem thermal properties suggested the system may also detect the onset of water stress. A field study showed the gauges could run for 1 to 2 weeks on a small battery pack. Sap flow measurements on multiple corn stems were scaled up by population to estimate field-scale transpiration. During full canopy cover, excellent agreement was observed between the scaled-up sap flow measurements and reference crop evapotranspiration calculated from weather data. Data also showed promise as a way to estimate real-time canopy resistance required for model verification and development. Given the low

Masslessness of ghosts in equivariantly gauge-fixed Yang-Mills theories

DOE Office of Scientific and Technical Information (OSTI.GOV)

Golterman, Maarten; Zimmerman, Leah

2005-06-01

We show that the one-loop ghost self-energy in an equivariantly gauge-fixed Yang-Mills theory vanishes at zero momentum. A ghost mass is forbidden by equivariant BRST symmetry, and our calculation confirms this explicitly. The four-ghost self interaction which appears in the equivariantly gauge-fixed Yang-Mills theory is needed in order to obtain this result.

Critical solutions of topologically gauged = 8 CFTs in three dimensions

NASA Astrophysics Data System (ADS)

Nilsson, Bengt E. W.

2014-04-01

In this paper we discuss some special (critical) background solutions that arise in topological gauged = 8 three-dimensional CFTs with SO(N) gauge group. Depending on how many scalar fields are given a VEV the theory has background solutions for certain values of μl, where μ and l are parameters in the TMG Lagrangian. Apart from Minkowski, chiral round AdS 3 and null-warped AdS 3 (or Schrödinger( z = 2)) we identify also a more exotic solution recently found in TMG by Ertl, Grumiller and Johansson. We also discuss the spectrum, symmetry breaking pattern and the supermultiplet structure in the various backgrounds and argue that some properties are due to their common origin in a conformal phase. Some of the scalar fields, including all higgsed ones, turn out to satisfy three-dimensional field equations similar to those of the singleton. Finally, we note that topologically gauged = 6 ABJ(M) theories have a similar, but more restricted, set of background solutions.

Gauge field entanglement in Kitaev's honeycomb model

NASA Astrophysics Data System (ADS)

Dóra, Balázs; Moessner, Roderich

2018-01-01

A spin fractionalizes into matter and gauge fermions in Kitaev's spin liquid on the honeycomb lattice. This follows from a Jordan-Wigner mapping to fermions, allowing for the construction of a minimal entropy ground-state wave function on the cylinder. We use this to calculate the entanglement entropy by choosing several distinct partitionings. First, by partitioning an infinite cylinder into two, the -ln2 topological entanglement entropy is reconfirmed. Second, the reduced density matrix of the gauge sector on the full cylinder is obtained after tracing out the matter degrees of freedom. This allows for evaluating the gauge entanglement Hamiltonian, which contains infinitely long-range correlations along the symmetry axis of the cylinder. The matter-gauge entanglement entropy is (Ny-1 )ln2 , with Ny the circumference of the cylinder. Third, the rules for calculating the gauge sector entanglement of any partition are determined. Rather small correctly chosen gauge partitions can still account for the topological entanglement entropy in spite of long-range correlations in the gauge entanglement Hamiltonian.

Program package for multicanonical simulations of U(1) lattice gauge theory-Second version

NASA Astrophysics Data System (ADS)

Bazavov, Alexei; Berg, Bernd A.

2013-03-01

A new version STMCMUCA_V1_1 of our program package is available. It eliminates compatibility problems of our Fortran 77 code, originally developed for the g77 compiler, with Fortran 90 and 95 compilers. New version program summaryProgram title: STMC_U1MUCA_v1_1 Catalogue identifier: AEET_v1_1 Licensing provisions: Standard CPC license, http://cpc.cs.qub.ac.uk/licence/licence.html Programming language: Fortran 77 compatible with Fortran 90 and 95 Computers: Any capable of compiling and executing Fortran code Operating systems: Any capable of compiling and executing Fortran code RAM: 10 MB and up depending on lattice size used No. of lines in distributed program, including test data, etc.: 15059 No. of bytes in distributed program, including test data, etc.: 215733 Keywords: Markov chain Monte Carlo, multicanonical, Wang-Landau recursion, Fortran, lattice gauge theory, U(1) gauge group, phase transitions of continuous systems Classification: 11.5 Catalogue identifier of previous version: AEET_v1_0 Journal Reference of previous version: Computer Physics Communications 180 (2009) 2339-2347 Does the new version supersede the previous version?: Yes Nature of problem: Efficient Markov chain Monte Carlo simulation of U(1) lattice gauge theory (or other continuous systems) close to its phase transition. Measurements and analysis of the action per plaquette, the specific heat, Polyakov loops and their structure factors. Solution method: Multicanonical simulations with an initial Wang-Landau recursion to determine suitable weight factors. Reweighting to physical values using logarithmic coding and calculating jackknife error bars. Reasons for the new version: The previous version was developed for the g77 compiler Fortran 77 version. Compiler errors were encountered with Fortran 90 and Fortran 95 compilers (specified below). Summary of revisions: epsilon=one/10**10 is replaced by epsilon/10.0D10 in the parameter statements of the subroutines u1_bmha.f, u1_mucabmha.f, u1wl

Weak ferromagnetic order breaking the threefold rotational symmetry of the underlying kagome lattice in CdC u3(OH) 6(NO3)2.H2O

NASA Astrophysics Data System (ADS)

Okuma, Ryutaro; Yajima, Takeshi; Nishio-Hamane, Daisuke; Okubo, Tsuyoshi; Hiroi, Zenji

2017-03-01

Novel magnetic phases are expected to occur in highly frustrated spin systems. Here, we study the structurally perfect kagome antiferromagnet CdC u3(OH) 6(NO3)2.H2O by magnetization, magnetic torque, and heat capacity measurements using single crystals. An antiferromagnetic order accompanied by a small spontaneous magnetization that surprisingly is confined in the kagome plane sets in at TN˜4 K , well below the nearest-neighbor exchange interaction J /kB=45 K . This suggests that a unique "q =0 " type 120∘ spin structure with "negative" (downward) vector chirality, which breaks the underlying threefold rotational symmetry of the kagome lattice and thus allows a spin canting within the plane, is exceptionally realized in this compound rather than a common one with "positive" (upward) vector chirality. The origin is discussed in terms of the Dzyaloshinskii-Moriya interaction.

Higher spin conformal geometry in three dimensions and prepotentials for higher spin gauge fields

NASA Astrophysics Data System (ADS)

Henneaux, Marc; Hörtner, Sergio; Leonard, Amaury

2016-01-01

We study systematically the conformal geometry of higher spin bosonic gauge fields in three spacetime dimensions. We recall the definition of the Cotton tensor for higher spins and establish a number of its properties that turn out to be key in solving in terms of prepotentials the constraint equations of the Hamiltonian (3 + 1) formulation of four-dimensional higher spin gauge fields. The prepotentials are shown to exhibit higher spin conformal symmetry. Just as for spins 1 and 2, they provide a remarkably simple, manifestly duality invariant formulation of the theory. While the higher spin conformal geometry is developed for arbitrary bosonic spin, we explicitly perform the Hamiltonian analysis and derive the solution of the constraints only in the illustrative case of spin 3. In a separate publication, the Hamiltonian analysis in terms of prepotentials is extended to all bosonic higher spins using the conformal tools of this paper, and the same emergence of higher spin conformal symmetry is confirmed.

Dual symmetry in a generalized Maxwell theory

NASA Astrophysics Data System (ADS)

Brandt, F. T.; Frenkel, J.; McKeon, D. G. C.

2016-09-01

We examine Podolsky’s electrodynamics, which is non-invariant under the usual duality transformation. We deduce a generalization of Hodge’s star duality, which leads to a dual gauge field and restores to a certain extent the dual symmetry. The model becomes fully dual symmetric asymptotically, when it reduces to the Maxwell theory. We argue that this strict dual symmetry directly implies the existence of the basic invariants of the electromagnetic fields.

The deviations of the Al6Li3Cu quasicrystal from icosahedral symmetry : a reminiscence of a cubic crystal

NASA Astrophysics Data System (ADS)

Donnadieu, Patricia

1994-05-01

The (Al6Li3Cu) (T2) quasicrystals are known to exhibit large deviations from the icosahedral symmetry. Series of electron diffraction patterns are used to investigate these imperfections in as-cast T, samples. A detailed analysis of the 5-fold and 3-fold symmetry diffraction patterns shows that they are compatible with the m3 point group instead of the m35 icosahedral group. This symmetry reduction is interprétéd as reminiscent of the cubic approximant phase (R-Al5Li3Cu) rather than of higher order approximant phases. This interpretation is supported by previous observations on crystal/quasicrystal phase transformation in the AlLiCu system. Les quasicristaux de phase T2(Al6Li3Cu) montrent d'importantes déviations à la symétrie icosaédrique. Ces imperfections sont mises en évidence par diffraction électronique dans des échantillons de phase T2 brut de coulée. Un examen détaillé des diagrammes de diffraction de symétrie d'ordre 3 et 5 révèle qu'ils sont compatibles avec le groupe ponctuel m3 au lieu du groupe de l'icosaèdre (m35). Cette réduction de symétrie est interprétée comme une réminiscence de la phase cubique approximante (R-Al5Li3Cu) et non l'apparition d'approximant d'ordre plus élevé. Cette interprétation est suggérée par des observations antérieures sur la transformation cristal/quasicristal dans le système AlLiCu.

Higgsing the stringy higher spin symmetry

DOE PAGES

Gaberdiel, Matthias R.; Peng, Cheng; Zadeh, Ida G.

2015-10-01

It has recently been argued that the symmetric orbifold theory of T 4 is dual to string theory on AdS 3 × S 3 × T 4 at the tensionless point. At this point in moduli space, the theory possesses a very large symmetry algebra that includes, in particular, a W ∞ algebra capturing the gauge fields of a dual higher spin theory. Using conformal perturbation theory, we study the behaviour of the symmetry generators of the symmetric orbifold theory under the deformation that corresponds to switching on the string tension. We show that the generators fall nicely into Reggemore » trajectories, with the higher spin fields corresponding to the leading Regge trajectory. We also estimate the form of the Regge trajectories for large spin, and find evidence for the familiar logarithmic behaviour, thereby suggesting that the symmetric orbifold theory is dual to an AdS background with pure RR flux.« less

2T Physics, Weyl Symmetry and the Geodesic Completion of Black Hole Backgrounds

NASA Astrophysics Data System (ADS)

Araya Quezada, Ignacio Jesus

In this thesis, we discuss two different contexts where the idea of gauge symmetry and duality is used to solve the dynamics of physical systems. The first of such contexts is 2T-physics in the worldline in d+2 dimensions, where the principle of Sp(2,R) gauge symmetry in phase space is used to relate different 1T systems in (d -- 1) + 1 dimensions, such as a free relativistic particle, and a relativistic particle in an arbitrary V(x2) potential. Because each 1T shadow system corresponds to a particular gauge of the underlying symmetry, there is a web of dualities relating them. The dualities between said systems amount to canonical transformations including time and energy, which allows the different systems to be described by different Hamiltonians, and consequently, to correspond to different dynamics in the (d -- 1)+1 phase space. The second context, corresponds to a Weyl invariant scalar-tensor theory of gravity, obtained as a direct prediction of 2T gravity, where the Weyl symmetry is used to obtain geodesically complete dynamics both in the context of cosmology and black hole (BH) backgrounds. The geodesic incompleteness of usual Einstein gravity, in the presence of singularities in spacetime, is related to the definition of the Einstein gauge, which fixes the sign and magnitude of the gravitational constant GN, and therefore misses the existence of antigravity patches, which are expected to arise generically just beyond gravitational singularities. The definition of the Einstein gauge can be generalized by incorporating a sign flip of the gravitational constant GN at the transitions between gravity and antigravity. This sign is a key aspect that allows us to define geodesically complete dynamics in cosmology and in BH backgrounds, particularly, in the case of the 4D Schwarzschild BH and the 2D stringy BH. The complete nature of particle geodesics in these BH backgrounds is exhibited explicitly at the classical level, and the extension of these results to the

2D Kac-Moody symmetry of 4D Yang-Mills theory

DOE PAGES

He, Temple; Mitra, Prahar; Strominger, Andrew

2016-10-25

Scattering amplitudes of any four-dimensional theory with nonabelian gauge group G may be recast as two-dimensional correlation functions on the asymptotic twosphere at null in nity. The soft gluon theorem is shown, for massless theories at the semiclassical level, to be the Ward identity of a holomorphic two-dimensional G-Kac-Moody symmetry acting on these correlation functions. Holomorphic Kac-Moody current insertions are positive helicity soft gluon insertions. Furthermore, the Kac-Moody transformations are a CPT invariant subgroup of gauge transformations which act nontrivially at null in nity and comprise the four-dimensional asymptotic symmetry group.

Some Quantum Symmetries and Their Breaking II

NASA Astrophysics Data System (ADS)

Selesnick, S. A.

2013-04-01

We consider symmetry breaking in the context of vector bundle theory, which arises quite naturally not only when attempting to "gauge" symmetry groups, but also as a means of localizing those global symmetry breaking effects known as spontaneous. We review such spontaneous symmetry breaking first for a simplified version of the Goldstone scenario for the case of global symmetries, and then in a localized form which is applied to a derivation of some of the phenomena associated with superconduction in both its forms, type I and type II. We then extend these procedures to effect the Higgs mechanism of electroweak theory, and finally we describe an extension to the flavor symmetries of the lightest quarks, including a brief discussion of CP-violation in the neutral kaon system. A largely self-contained primer of vector bundle theory is provided in Sect. 4, which supplies most of the results required thereafter.

On the symmetries of the 12C nucleus

NASA Astrophysics Data System (ADS)

Cseh, J.; Trencsényi, R.

The consequences of some symmetries of the three-alpha system are discussed. In particular, the recent description of the low-energy spectrum of the 12C nucleus in terms of the algebraic cluster model (ACM) is compared to that of the multichannel dynamical symmetry (MUSY), which is the intersection of the shell and cluster models. The previous one applies interactions of a D3h geometric symmetry [D. J. Marin-Lambarri et al., Phys. Rev. Lett. 113 (2014) 012502], while the latter one has a U(3) dynamical symmetry. The available data is in line with both descriptions.

Detecting the Lμ-Lτ gauge boson at Belle II

NASA Astrophysics Data System (ADS)

Araki, Takeshi; Hoshino, Shihori; Ota, Toshihiko; Sato, Joe; Shimomura, Takashi

2017-03-01

We discuss the feasibility of detecting the gauge boson of the U (1 )Lμ-Lτ symmetry, which possesses a mass in the range between MeV and GeV, at the Belle-II experiment. The kinetic mixing between the new gauge boson Z' and photon is forbidden at the tree level and is radiatively induced. The leptonic force mediated by such a light boson is motivated by the discrepancy in muon anomalous magnetic moment and also the gap in the energy spectrum of cosmic neutrino. Defining the process e+e-→γ Z'→γ ν ν ¯ (missing energy) to be the signal, we estimate the numbers of the signal and the background events and show the parameter region to which the Belle-II experiment will be sensitive. The signal process in the Lμ-Lτ model is enhanced with a light Z', which is a characteristic feature differing from the dark photon models with a constant kinetic mixing. We find that the Belle-II experiment with the design luminosity will be sensitive to the Z' with the mass MZ'≲1 GeV and the new gauge coupling gZ'≳8 ×10-4 , which covers a half of the unconstrained parameter region that explains the discrepancy in muon anomalous magnetic moment. The possibilities to improve the significance of the detection are also discussed.

Diffractive Scattering and Gauge/String Duality

ScienceCinema

Tan, Chung-I

2018-05-11

High-energy diffractive scattering will be discussed based on Gauge/String duality. As shown by Brower, Polchinski, Strassler and Tan, the ubiquitous Pomeron emerges naturally in gauge theories with string-theoretical descriptions. Its existence is intimately tied to gluons, and also to the energy-momentum tensor. With a confining dual background metric, the Pomeron can be interpreted as a 'massive graviton'. In a single unified step, both its infrared and ultraviolet properties are dealt with, reflecting confinement and conformal symmetry respectively. An effective field theory for high-energy scattering can be constructed. Applications based on this approach will also be described.

Gauge fixing in higher-derivative gravity

NASA Astrophysics Data System (ADS)

Bartoli, A.; Julve, J.; Sánchez, E. J.

1999-07-01

Linearized 4-derivative gravity with a general gauge-fixing term is considered. By a Legendre transform and a suitable diagonalization procedure it is cast into a second-order equivalent form where the nature of the physical degrees of freedom, the gauge ghosts, the Weyl ghosts and the intriguing `third ghosts', characteristic to higher-derivative theories, is made explicit. The symmetries of the theory and the structure of the compensating Faddeev-Popov ghost sector exhibit non-trivial peculiarities. The unitarity breaking negative-norm Weyl ghosts, already present in the diff-invariant theory, are out of the reach of the ghost cancellation BRST mechanism.

Black hole attractors and gauge theories

NASA Astrophysics Data System (ADS)

Huang, Lisa Li Fang

2007-12-01

This thesis is devoted to the study of supersymmetric black holes that arise from string compactifications. We begin by studying the R 2 corrections to the entropy of two solutions of five dimensional supergravity, the supersymmetric black ring and the spinning black hole. Using Wald's formula we compute the R2 corrections to the entropy of the black ring and BMPV black hole. We study N D4-branes wrapping a 4 cycle and M DO-branes on the quintic. For N D4-branes, we resolve the naive mismatch between the moduli space of the Higgs branch of the gauge theory and the moduli of a degree N hypersurface which the D4-brane wraps. The degree N surface must admit a holomorphic divisor and is a determinantal variety. Adding a single DO brane to probe the deformed geometry, we recover the determinant equation from F and D flatness condition which was previously discovered from a classical geometry approach. We next generalize the qunitic story for Calabi-Yau manifolds arising from complete intersections in toric varieties. We recover the moduli space of N D4-branes in terms of the moduli space of a U( N) x U(N) gauge theory with bi-fundamentals com ing from a D6 - D6 system. We also recast the tachyon condensation of the D6 - D6 system in the language of open string gauged linear sigma model. We obtain the determinant equation from F-term constraints arising from a boundary coupling. We set out to understand the Ooguri-Strominger-Vafa conjecture directly in the D4-DO black hole attractor geometry. We show that the lift to the euclidean IIA attractor geometry gives a complexified M-theory geometry whose asymptotic boundary is a torus. Employing AdS3/CFT 2 duality, we argue that the string partition function computes the elliptic genus of the Maldacena-Strominger-Witten conformal field theory. We evaluate the IIA partition function using the Green-Schwarz formalism and show that it gives ZtopZ top, coming from instantons and anti-instantons respectively. Finally, we determine

A simple example of a classical gauge transformation

NASA Technical Reports Server (NTRS)

Whitten, R. C.

1983-01-01

Attention is given to the manner in which the interaction of a gravitational field with a diffusing gas is induced by a gauge transformation. Since the gas can be thought of as a field, the diffusion process may be represented by a Lagrangian density with the symmetry property of invariance under translation. While this property is lost when the field interacts with a static gravitational field, it is formally restored when an appropriate gauge transformation is performed. This ascription of field properties to a gas offers an illuminating illustration of the coupling of matter to a gauge field within the context of classical mechanics.

Lattice implementation of Abelian gauge theories with Chern-Simons number and an axion field

NASA Astrophysics Data System (ADS)

Figueroa, Daniel G.; Shaposhnikov, Mikhail

2018-01-01

Real time evolution of classical gauge fields is relevant for a number of applications in particle physics and cosmology, ranging from the early Universe to dynamics of quark-gluon plasma. We present an explicit non-compact lattice formulation of the interaction between a shift-symmetric field and some U (1) gauge sector, a (x)FμνF˜μν, reproducing the continuum limit to order O (dxμ2) and obeying the following properties: (i) the system is gauge invariant and (ii) shift symmetry is exact on the lattice. For this end we construct a definition of the topological number density K =FμνF˜μν that admits a lattice total derivative representation K = Δμ+ Kμ, reproducing to order O (dxμ2) the continuum expression K =∂μKμ ∝ E → ṡ B → . If we consider a homogeneous field a (x) = a (t), the system can be mapped into an Abelian gauge theory with Hamiltonian containing a Chern-Simons term for the gauge fields. This allow us to study in an accompanying paper the real time dynamics of fermion number non-conservation (or chirality breaking) in Abelian gauge theories at finite temperature. When a (x) = a (x → , t) is inhomogeneous, the set of lattice equations of motion do not admit however a simple explicit local solution (while preserving an O (dxμ2) accuracy). We discuss an iterative scheme allowing to overcome this difficulty.

String duality transformations in f(R) gravity from Noether symmetry approach

DOE Office of Scientific and Technical Information (OSTI.GOV)

Capozziello, Salvatore; Gionti, Gabriele S.J.; Vernieri, Daniele, E-mail: capozziello@na.inf.it, E-mail: ggionti@as.arizona.edu, E-mail: vernieri@iap.fr

2016-01-01

We select f(R) gravity models that undergo scale factor duality transformations. As a starting point, we consider the tree-level effective gravitational action of bosonic String Theory coupled with the dilaton field. This theory inherits the Busher's duality of its parent String Theory. Using conformal transformations of the metric tensor, it is possible to map the tree-level dilaton-graviton string effective action into f(R) gravity, relating the dilaton field to the Ricci scalar curvature. Furthermore, the duality can be framed under the standard of Noether symmetries and exact cosmological solutions are derived. Using suitable changes of variables, the string-based f(R) Lagrangians aremore » shown in cases where the duality transformation becomes a parity inversion.« less

Synthesis, Electrochemistry, and Reactivity of the Actinide Trisulfides [K(18-crown-6)][An(η(3)-S3)(NR2)3] (An = U, Th; R = SiMe3).

PubMed

Smiles, Danil E; Wu, Guang; Hayton, Trevor W

2016-09-19

The reaction of [Th(I)(NR2)3] (R = SiMe3) with [K(18-crown-6)]2[S4] results in the formation of [K(18-crown-6)][Th(η(3)-S3)(NR2)3] (2). Oxidation of 2, or its uranium analogue, [K(18-crown-6)][U(η(3)-S3)(NR2)3] (1), with AgOTf, in an attempt to generate an [S3](•-) complex, results in the formation of [K(18-crown-6)][An(OTf)2(NR2)3] (3, An = U; 4, An = Th) as the only isolable products. These results suggest that the putative [S3](•-) ligand is only weakly coordinating and can be easily displaced by nucleophiles.

Luminescence and Excitation Spectra of U 3+ doped RbY 2 Cl 7 Single Crystals

DOE PAGES

Karbowiak, M.; Murdoch, K.; Drożdżyński, J.; ...

1996-08-01

Uranium(3+) doped single crystals of RbY 2 Cl 7 with a uranium concentration of 0.05% and 0.2% were grown by the Bridgman-Stockbarger method using RbU 2 Cl 7 as the doping substance. Polished plates of ca. 5 mm in diameter were used for measurements of luminescence and excitation spectra. And since the U 3+ ions occupy two somewhat different site symmetries, a splitting of all observed f-f bands was observed. Furthermore, the analysis of the spectra enabled definitively an assignment of 22 crystal field bands for both site symmetries as well as the total crystal field splitting of the groundmore » level, equal to 473 cm -1 and 567 cm -1 for the first and second site symmetry, respectively.« less

Null hypersurface quantization, electromagnetic duality and asympotic symmetries of Maxwell theory

NASA Astrophysics Data System (ADS)

Bhattacharyya, Arpan; Hung, Ling-Yan; Jiang, Yikun

2018-03-01

In this paper we consider introducing careful regularization at the quantization of Maxwell theory in the asymptotic null infinity. This allows systematic discussions of the commutators in various boundary conditions, and application of Dirac brackets accordingly in a controlled manner. This method is most useful when we consider asymptotic charges that are not localized at the boundary u → ±∞ like large gauge transformations. We show that our method reproduces the operator algebra in known cases, and it can be applied to other space-time symmetry charges such as the BMS transformations. We also obtain the asymptotic form of the U(1) charge following from the electromagnetic duality in an explicitly EM symmetric Schwarz-Sen type action. Using our regularization method, we demonstrate that the charge generates the expected transformation of a helicity operator. Our method promises applications in more generic theories.

Test of SU(3) Symmetry in Hyperon Semileptonic Decays

NASA Astrophysics Data System (ADS)

Pham, T. N.

2015-01-01

Existing analyzes of baryon semileptonic decays indicate the presence of a small SU(3) symmetry breaking in hyperon semileptonic decays, but to provide evidence for SU(3) symmetry breaking, one would need a relation similar to the Gell-Mann-Okubo (GMO) baryon mass formula which is satisfied to a few percents, showing evidence for a small SU(3) symmetry breaking effect in the GMO mass formula. In this talk, I would like to present a similar GMO relation obtained in a recent work for hyperon semileptonic decay axial vector current matrix elements. Using these generalized GMO relations for the measured axial vector current to vector current form factor ratios, it is shown that SU(3) symmetry breaking in hyperon semileptonic decays is of 5-11% and confirms the validity of the Cabibbo model for hyperon semi-leptonic decays.

Local subsystems in gauge theory and gravity

DOE PAGES

Donnelly, William; Freidel, Laurent

2016-09-16

We consider the problem of defining localized subsystems in gauge theory and gravity. Such systems are associated to spacelike hypersurfaces with boundaries and provide the natural setting for studying entanglement entropy of regions of space. We present a general formalism to associate a gauge-invariant classical phase space to a spatial slice with boundary by introducing new degrees of freedom on the boundary. In Yang-Mills theory the new degrees of freedom are a choice of gauge on the boundary, transformations of which are generated by the normal component of the nonabelian electric field. In general relativity the new degrees of freedommore » are the location of a codimension-2 surface and a choice of conformal normal frame. These degrees of freedom transform under a group of surface symmetries, consisting of diffeomorphisms of the codimension-2 boundary, and position-dependent linear deformations of its normal plane. We find the observables which generate these symmetries, consisting of the conformal normal metric and curvature of the normal connection. We discuss the implications for the problem of defining entanglement entropy in quantum gravity. Finally, our work suggests that the Bekenstein-Hawking entropy may arise from the different ways of gluing together two partial Cauchy surfaces at a cross-section of the horizon.« less

Killing and Noether Symmetries of Plane Symmetric Spacetime

NASA Astrophysics Data System (ADS)

Shamir, M. Farasat; Jhangeer, Adil; Bhatti, Akhlaq Ahmad

2013-09-01

This paper is devoted to investigate the Killing and Noether symmetries of static plane symmetric spacetime. For this purpose, five different cases have been discussed. The Killing and Noether symmetries of Minkowski spacetime in cartesian coordinates are calculated as a special case and it is found that Lie algebra of the Lagrangian is 10 and 17 dimensional respectively. The symmetries of Taub's universe, anti-deSitter universe, self similar solutions of infinite kind for parallel perfect fluid case and self similar solutions of infinite kind for parallel dust case are also explored. In all the cases, the Noether generators are calculated in the presence of gauge term. All these examples justify the conjecture that Killing symmetries form a subalgebra of Noether symmetries (Bokhari et al. in Int. J. Theor. Phys. 45:1063, 2006).

Symmetry of Highly-Strained BiFeO3 Films in the Ultrathin Regime

NASA Astrophysics Data System (ADS)

Yang, Yongsoo; Senabulya, Nancy; Clarke, Roy; Schlepütz, Christian M.; Beekman, Christianne; Siemons, Wolter; Christen, Hans M.

2014-03-01

At room temperature, highly-strained BiFeO3 (BFO) films grown on LaAlO3 substrates exhibit a monoclinic structure with a giant c/a ratio (~1.3) when the films are thicker than 4 nm. Their structural symmetry can be controlled by adjusting the temperature [Appl. Phys. Express 4, 095801 (2011), Adv. Mater. 25, 5561 (2013)], with a high-temperature tetragonal phase being observed. We report that a structural phase transition can also be achieved by controlling the film thickness: synchrotron x-ray diffraction data shows that the Bragg peak splitting associated with the monoclinic phase disappears as the film thickness decreases below 3 nm, indicating a tetragonal symmetry, but still maintaining the giant c/a ratio. Unlike a similar transition reported for moderately strained BFO grown on SrTiO3 [APL Mater. 1, 052102 (2013)], the half-order Bragg peaks indicate that this transition does not involve a significant change in the octahedral tilt pattern of the film. This suggests that the structural evolution of highly-strained BFO films should be understood in terms of the unique (non-octahedral) oxygen coordination of the Fe ion in this highly-strained BFO, not the corner-connectivity of the oxygen octahedra between the film and the substrate. Funding: U.S. Department of Energy, BES-MSED (U. Michigan: DE-FG02-06ER46273, and at ORNL). Measurements: 13-BMC, 33-IDD, 33-BMC of the Advanced Photon Source, ANL (DE-AC02-06CH11357).

3 d printing of 2 d N=(0,2) gauge theories

NASA Astrophysics Data System (ADS)

Franco, Sebastián; Hasan, Azeem

2018-05-01

We introduce 3 d printing, a new algorithm for generating 2 d N=(0,2) gauge theories on D1-branes probing singular toric Calabi-Yau 4-folds using 4 d N=1 gauge theories on D3-branes probing toric Calabi-Yau 3-folds as starting points. Equivalently, this method produces brane brick models starting from brane tilings. 3 d printing represents a significant improvement with respect to previously available tools, allowing a straightforward determination of gauge theories for geometries that until now could only be tackled using partial resolution. We investigate the interplay between triality, an IR equivalence between different 2 d N=(0,2) gauge theories, and the freedom in 3 d printing given an underlying Calabi-Yau 4-fold. Finally, we present the first discussion of the consistency and reduction of brane brick models.

Universal seesaw and 0νββ in new 3331 left-right symmetric model

NASA Astrophysics Data System (ADS)

Borah, Debasish; Patra, Sudhanwa

2017-08-01

We consider a class of left-right symmetric model with enlarged gauge group SU(3)c × SU(3)L × SU(3)R × U(1)X without having scalar bitriplet. In the absence of scalar bitriplet, there is no Dirac mass term for fermions including usual quarks and leptons. We introduce new isosinglet vector-like fermions so that all the fermions get their masses through a universal seesaw mechanism. We extend our discussion to neutrino mass and its implications in neutrinoless double beta decay (0 νββ). We show that for TeV scale SU(3)R gauge bosons, the heavy-light neutrino mixing contributes dominantly to 0 νββ that can be observed at ongoing experiments. The new physics contributions arising from purely left-handed currents via exchange of keV scale right-handed neutrinos and the so called mixed helicity λ-diagram can saturate the KamLANDZen bound. We show that the right handed neutrinos in this model can have mass in the sub keV range and can be long lived compared to the age of the Universe. The contributions of these right handed neutrinos to flavour physics observables like μ → eγ and muon g - 2 is also discussed. Towards the end we also comment on different possible symmetry breaking patterns of this enlarged gauge symmetry to that of the standard model.

Highly effective action from large N gauge fields

NASA Astrophysics Data System (ADS)

Yang, Hyun Seok

2014-10-01

Recently Schwarz put forward a conjecture that the world-volume action of a probe D3-brane in an AdS5×S5 background of type IIB superstring theory can be reinterpreted as the highly effective action (HEA) of four-dimensional N =4 superconformal field theory on the Coulomb branch. We argue that the HEA can be derived from the noncommutative (NC) field theory representation of the AdS/CFT correspondence and the Seiberg-Witten (SW) map defining a spacetime field redefinition between ordinary and NC gauge fields. It is based only on the well-known facts that the master fields of large N matrices are higher-dimensional NC U(1) gauge fields and the SW map is a local coordinate transformation eliminating U(1) gauge fields known as the Darboux theorem in symplectic geometry.

Critical fermion density for restoring spontaneously broken symmetry

NASA Astrophysics Data System (ADS)

Kleinert, Hagen; Xue, She-Sheng

2015-07-01

We show how the phenomenon of spontaneous symmetry breakdown is affected by the presence of a sea of fermions in the system. When its density exceeds a critical value, the broken symmetry can be restored. We calculate the critical value and discuss the consequences for three different physical systems: First, for the Standard Model (SM) of particle physics, where the spontaneous symmetry breakdown leads to nonzero masses of intermediate gauge bosons and fermions. The symmetry restoration will greatly enhance various processes with dramatic consequences for the early universe. Second, for the Gell-Mann-Lévy σ-model of nuclear physics, where the symmetry breakdown gives rise to the nucleon and meson masses. The symmetry restoration may have important consequences for formation or collapse of stellar cores. Third, for the superconductive phase of condensed-matter, where the BCS condensate at low-temperature may be destroyed by a too large electron density.

Creating 3, 4, 6 and 10-dimensional spacetime from W3 symmetry

NASA Astrophysics Data System (ADS)

Ambjørn, J.; Watabiki, Y.

2017-07-01

We describe a model where breaking of W3 symmetry will lead to the emergence of time and subsequently of space. Surprisingly the simplest such models which lead to higher dimensional spacetimes are based on the four ;magical; Jordan algebras of 3 × 3 Hermitian matrices with real, complex, quaternion and octonion entries, respectively. The simplest symmetry breaking leads to universes with spacetime dimensions 3, 4, 6, and 10.

A High Precision $3.50 Open Source 3D Printed Rain Gauge Calibrator

NASA Astrophysics Data System (ADS)

Lopez Alcala, J. M.; Udell, C.; Selker, J. S.

2017-12-01

Currently available rain gauge calibrators tend to be designed for specific rain gauges, are expensive, employ low-precision water reservoirs, and do not offer the flexibility needed to test the ever more popular small-aperture rain gauges. The objective of this project was to develop and validate a freely downloadable, open-source, 3D printed rain gauge calibrator that can be adjusted for a wide range of gauges. The proposed calibrator provides for applying low, medium, and high intensity flow, and allows the user to modify the design to conform to unique system specifications based on parametric design, which may be modified and printed using CAD software. To overcome the fact that different 3D printers yield different print qualities, we devised a simple post-printing step that controlled critical dimensions to assure robust performance. Specifically, the three orifices of the calibrator are drilled to reach the three target flow rates. Laboratory tests showed that flow rates were consistent between prints, and between trials of each part, while the total applied water was precisely controlled by the use of a volumetric flask as the reservoir.

Study of the 190Hg Nucleus: Testing the Existence of U(5) Symmetry

NASA Astrophysics Data System (ADS)

Jahangiri Tazekand, Z.; Mohseni, M.; Mohammadi, M. A.; Sabri, H.

2018-06-01

In this paper, we have considered the energy spectra, quadrupole transition probabilities, energy surface, charge radii, and quadrupole moment of the190Hg nucleus to describe the interplay between phase transitions and configuration mixing of intruder excitations. To this aim, we have used four different formalisms: (i) interacting boson model including configuration mixing, (ii) Z(5) critical symmetry, (iii) U(6)-based transitional Hamiltonian, and (iv) a transitional interacting boson model Hamiltonian in both interacting boson model (IBM)-1 and IBM-2 versions which are based on affine \\widehat{SU(1,1)} Lie algebra. Results show the advantages of configuration mixing and transitional Hamiltonians, in particular IBM-2 formalism, to reproduce the experimental counterparts when the weight of spherical symmetry increased.

Probing strong electroweak symmetry breaking dynamics through quantum interferometry at the LHC

DOE PAGES

Murayama, Hitoshi; Rentala, Vikram; Shu, Jing

2015-12-07

Here, we present a new probe of strongly coupled electroweak symmetry breaking at the 14 TeV LHC by measuring a phase shift in the event distribution of the decay azimuthal angles in massive gauge boson scattering. One generically expects a large phase shift in the longitudinal gauge boson scattering amplitude due to the presence of broad resonances. This phase shift is observable as an interference effect between the strongly interacting longitudinal modes and the transverse modes of the gauge bosons. We find that even very broad resonances of masses up to 900 GeV can be probed at 3σ significance withmore » a 3000 fb -1 run of the LHC by using this technique. We also present the estimated reach for a future 50 TeV proton-proton collider.« less

Gauge Theories of Vector Particles

DOE R&D Accomplishments Database

Glashow, S. L.; Gell-Mann, M.

1961-04-24

The possibility of generalizing the Yang-Mills trick is examined. Thus we seek theories of vector bosons invariant under continuous groups of coordinate-dependent linear transformations. All such theories may be expressed as superpositions of certain "simple" theories; we show that each "simple theory is associated with a simple Lie algebra. We may introduce mass terms for the vector bosons at the price of destroying the gauge-invariance for coordinate-dependent gauge functions. The theories corresponding to three particular simple Lie algebras - those which admit precisely two commuting quantum numbers - are examined in some detail as examples. One of them might play a role in the physics of the strong interactions if there is an underlying super-symmetry, transcending charge independence, that is badly broken. The intermediate vector boson theory of weak interactions is discussed also. The so-called "schizon" model cannot be made to conform to the requirements of partial gauge-invariance.

Fierz bilinear formulation of the Maxwell–Dirac equations and symmetry reductions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Inglis, Shaun, E-mail: sminglis@utas.edu.au; Jarvis, Peter, E-mail: Peter.Jarvis@utas.edu.au

We study the Maxwell–Dirac equations in a manifestly gauge invariant presentation using only the spinor bilinear scalar and pseudoscalar densities, and the vector and pseudovector currents, together with their quadratic Fierz relations. The internally produced vector potential is expressed via algebraic manipulation of the Dirac equation, as a rational function of the Fierz bilinears and first derivatives (valid on the support of the scalar density), which allows a gauge invariant vector potential to be defined. This leads to a Fierz bilinear formulation of the Maxwell tensor and of the Maxwell–Dirac equations, without any reference to gauge dependent quantities. We showmore » how demanding invariance of tensor fields under the action of a fixed (but arbitrary) Lie subgroup of the Poincaré group leads to symmetry reduced equations. The procedure is illustrated, and the reduced equations worked out explicitly for standard spherical and cylindrical cases, which are coupled third order nonlinear PDEs. Spherical symmetry necessitates the existence of magnetic monopoles, which do not affect the coupled Maxwell–Dirac system due to magnetic terms cancelling. In this paper we do not take up numerical computations. As a demonstration of the power of our approach, we also work out the symmetry reduced equations for two distinct classes of dimension 4 one-parameter families of Poincaré subgroups, one splitting and one non-splitting. The splitting class yields no solutions, whereas for the non-splitting class we find a family of formal exact solutions in closed form. - Highlights: • Maxwell–Dirac equations derived in manifestly gauge invariant tensor form. • Invariant scalar and four vector fields for four Poincaré subgroups derived, including two unusual cases. • Symmetry reduction imposed on Maxwell–Dirac equations under example subgroups. • Magnetic monopole arises for spherically symmetric case, consistent with charge quantization condition.« less

Towards Scalable Strain Gauge-Based Joint Torque Sensors

PubMed Central

D’Imperio, Mariapaola; Cannella, Ferdinando; Caldwell, Darwin G.; Cuschieri, Alfred

2017-01-01

During recent decades, strain gauge-based joint torque sensors have been commonly used to provide high-fidelity torque measurements in robotics. Although measurement of joint torque/force is often required in engineering research and development, the gluing and wiring of strain gauges used as torque sensors pose difficulties during integration within the restricted space available in small joints. The problem is compounded by the need for a scalable geometric design to measure joint torque. In this communication, we describe a novel design of a strain gauge-based mono-axial torque sensor referred to as square-cut torque sensor (SCTS), the significant features of which are high degree of linearity, symmetry, and high scalability in terms of both size and measuring range. Most importantly, SCTS provides easy access for gluing and wiring of the strain gauges on sensor surface despite the limited available space. We demonstrated that the SCTS was better in terms of symmetry (clockwise and counterclockwise rotation) and more linear. These capabilities have been shown through finite element modeling (ANSYS) confirmed by observed data obtained by load testing experiments. The high performance of SCTS was confirmed by studies involving changes in size, material and/or wings width and thickness. Finally, we demonstrated that the SCTS can be successfully implementation inside the hip joints of miniaturized hydraulically actuated quadruped robot-MiniHyQ. This communication is based on work presented at the 18th International Conference on Climbing and Walking Robots (CLAWAR). PMID:28820446

Towards Scalable Strain Gauge-Based Joint Torque Sensors.

PubMed

Khan, Hamza; D'Imperio, Mariapaola; Cannella, Ferdinando; Caldwell, Darwin G; Cuschieri, Alfred; Semini, Claudio

2017-08-18

During recent decades, strain gauge-based joint torque sensors have been commonly used to provide high-fidelity torque measurements in robotics. Although measurement of joint torque/force is often required in engineering research and development, the gluing and wiring of strain gauges used as torque sensors pose difficulties during integration within the restricted space available in small joints. The problem is compounded by the need for a scalable geometric design to measure joint torque. In this communication, we describe a novel design of a strain gauge-based mono-axial torque sensor referred to as square-cut torque sensor (SCTS) , the significant features of which are high degree of linearity, symmetry, and high scalability in terms of both size and measuring range. Most importantly, SCTS provides easy access for gluing and wiring of the strain gauges on sensor surface despite the limited available space. We demonstrated that the SCTS was better in terms of symmetry (clockwise and counterclockwise rotation) and more linear. These capabilities have been shown through finite element modeling (ANSYS) confirmed by observed data obtained by load testing experiments. The high performance of SCTS was confirmed by studies involving changes in size, material and/or wings width and thickness. Finally, we demonstrated that the SCTS can be successfully implementation inside the hip joints of miniaturized hydraulically actuated quadruped robot- MiniHyQ . This communication is based on work presented at the 18th International Conference on Climbing and Walking Robots (CLAWAR).

Strong dynamics and lattice gauge theory

NASA Astrophysics Data System (ADS)

Schaich, David

In this dissertation I use lattice gauge theory to study models of electroweak symmetry breaking that involve new strong dynamics. Electroweak symmetry breaking (EWSB) is the process by which elementary particles acquire mass. First proposed in the 1960s, this process has been clearly established by experiments, and can now be considered a law of nature. However, the physics underlying EWSB is still unknown, and understanding it remains a central challenge in particle physics today. A natural possibility is that EWSB is driven by the dynamics of some new, strongly-interacting force. Strong interactions invalidate the standard analytical approach of perturbation theory, making these models difficult to study. Lattice gauge theory is the premier method for obtaining quantitatively-reliable, nonperturbative predictions from strongly-interacting theories. In this approach, we replace spacetime by a regular, finite grid of discrete sites connected by links. The fields and interactions described by the theory are likewise discretized, and defined on the lattice so that we recover the original theory in continuous spacetime on an infinitely large lattice with sites infinitesimally close together. The finite number of degrees of freedom in the discretized system lets us simulate the lattice theory using high-performance computing. Lattice gauge theory has long been applied to quantum chromodynamics, the theory of strong nuclear interactions. Using lattice gauge theory to study dynamical EWSB, as I do in this dissertation, is a new and exciting application of these methods. Of particular interest is non-perturbative lattice calculation of the electroweak S parameter. Experimentally S ≈ -0.15(10), which tightly constrains dynamical EWSB. On the lattice, I extract S from the momentum-dependence of vector and axial-vector current correlators. I created and applied computer programs to calculate these correlators and analyze them to determine S. I also calculated the masses

On lattice chiral gauge theories

NASA Technical Reports Server (NTRS)

Maiani, L.; Rossi, G. C.; Testa, M.

1991-01-01

The Smit-Swift-Aoki formulation of a lattice chiral gauge theory is presented. In this formulation the Wilson and other non invariant terms in the action are made gauge invariant by the coupling with a nonlinear auxilary scalar field, omega. It is shown that omega decouples from the physical states only if appropriate parameters are tuned so as to satisfy a set of BRST identities. In addition, explicit ghost fields are necessary to ensure decoupling. These theories can give rise to the correct continuum limit. Similar considerations apply to schemes with mirror fermions. Simpler cases with a global chiral symmetry are discussed and it is shown that the theory becomes free at decoupling. Recent numerical simulations agree with those considerations.

Chiral symmetry breaking and the spin content of the ρ and ρ‧ mesons

NASA Astrophysics Data System (ADS)

Glozman, L. Ya.; Lang, C. B.; Limmer, M.

2011-11-01

Using interpolators with different SU(2)L × SU(2)R transformation properties we study the chiral symmetry and spin contents of the ρ and ρ‧ mesons in lattice simulations with dynamical quarks. A ratio of couplings of the qbarγi τq and qbarσ0i τq interpolators to a given meson state at different resolution scales tells one about the degree of chiral symmetry breaking in the meson wave function at these scales. Using a Gaussian gauge invariant smearing of the quark fields in the interpolators, we are able to extract the chiral content of mesons up to the infrared resolution of ∼ 1 fm. In the ground state ρ meson the chiral symmetry is strongly broken with comparable contributions of both the (0 , 1) + (1 , 0) and (1 / 2 , 1 / 2) b chiral representations with the former being the leading contribution. In contrast, in the ρ‧ meson the degree of chiral symmetry breaking is manifestly smaller and the leading representation is (1 / 2 , 1 / 2) b. Using a unitary transformation from the chiral basis to the LJ2S+1 basis, we are able to define and measure the angular momentum content of mesons in the rest frame. This definition is different from the traditional one which uses parton distributions in the infinite momentum frame. The ρ meson is practically a 3S1 state with no obvious trace of a "spin crisis". The ρ‧ meson has a sizeable contribution of the 3D1 wave, which implies that the ρ‧ meson cannot be considered as a pure radial excitation of the ρ meson.

Structural analysis of the human U3 ribonucleoprotein particle reveal a conserved sequence available for base pairing with pre-rRNA.

PubMed Central

Parker, K A; Steitz, J A

1987-01-01

The human U3 ribonucleoprotein (RNP) has been analyzed to determine its protein constituents, sites of protein-RNA interaction, and RNA secondary structure. By using anti-U3 RNP antibodies and extracts prepared from HeLa cells labeled in vivo, the RNP was found to contain four nonphosphorylated proteins of 36, 30, 13, and 12.5 kilodaltons and two phosphorylated proteins of 74 and 59 kilodaltons. U3 nucleotides 72-90, 106-121, 154-166, and 190-217 must contain sites that interact with proteins since these regions are immunoprecipitated after treatment of the RNP with RNase A or T1. The secondary structure was probed with specific nucleases and by chemical modification with single-strand-specific reagents that block subsequent reverse transcription. Regions that are single stranded (and therefore potentially able to interact with a substrate RNA) include an evolutionarily conserved sequence at nucleotides 104-112 and nonconserved sequences at nucleotides 65-74, 80-84, and 88-93. Nucleotides 159-168 do not appear to be highly accessible, thus making it unlikely that this U3 sequence base pairs with sequences near the 5.8S rRNA-internal transcribed spacer II junction, as previously proposed. Alternative functions of the U3 RNP are discussed, including the possibility that U3 may participate in a processing event near the 3' end of 28S rRNA. Images PMID:2959855

Instantons on a non-commutative T4 from twisted (2,0) and little string theories

NASA Astrophysics Data System (ADS)

Cheung, Yeuk-Kwan E.; Ganor, Ori J.; Krogh, Morten; Mikhailov, Andrei Yu.

We show that the moduli space of the (2,0) and little-string theories compactified on T3 with R-symmetry twists is equal to the moduli space of U(1) instantons on a non-commutative T4. The moduli space of U( q) instantons on a non-commutative T4 is obtained from little-string theories of NS5-branes at Aq-1 singularities with twists. A large class of gauge theories with N=4 SUSY in 2+1D and N=2 SUSY in 3+1D are limiting cases of these theories. Hence, the moduli spaces of these gauge theories can be read off from the moduli spaces of instantons on non-commutative tori. We study the phase transitions in these theories and the action of T-duality. On the purely mathematical side, we give a prediction for the moduli space of two U(1) instantons on a non-commutative T4.

Condensate cosmology in O'Raifeartaigh models

NASA Astrophysics Data System (ADS)

Barnard, James

2011-08-01

Flat directions charged under an R-symmetry are a generic feature of O'Raifeartaigh models. Non-topological solitons associated with this symmetry, R-balls, are likely to form through the fragmentation of a condensate, itself created by soft terms induced during inflation. In gravity mediated SUSY breaking R-balls decay to gravitinos, reheating the universe. For gauge mediation R-balls can provide a good dark matter candidate. Alternatively they can decay, either reheating or cooling the universe. Conserved R-symmetry permits decay to gravitinos or gauginos, whereas spontaneously broken R-symmetry results in decay to visible sector gauge bosons.

Nucleon-nucleon scattering parameters in the limit of SU(3) flavor symmetry

NASA Astrophysics Data System (ADS)

Beane, S. R.; Chang, E.; Cohen, S. D.; Detmold, W.; Junnarkar, P.; Lin, H. W.; Luu, T. C.; Orginos, K.; Parreño, A.; Savage, M. J.; Walker-Loud, A.

2013-08-01

The scattering lengths and effective ranges that describe low-energy nucleon-nucleon scattering are calculated in the limit of SU(3)-flavor symmetry at the physical strange-quark mass with lattice quantum chromodynamics. The calculations are performed with an isotropic clover discretization of the quark action in three volumes with spatial extents of L˜3.4fm, 4.5fm, and 6.7fm, and with a lattice spacing of b˜0.145fm. With determinations of the energies of the two-nucleon systems (both of which contain bound states at these up and down quark masses) at rest and moving in the lattice volume, Lüscher's method is used to determine the low-energy phase shifts in each channel, from which the scattering length and effective range are obtained. The scattering parameters, in the 1S0 channel are found to be mπa(1S0)=9.50-0.69+0.78-0.80+1.10 and mπr(1S0)=4.61-0.31+0.29-0.26+0.24, and in the 3S1 channel are mπa(3S1)=7.45-0.53+0.57-0.49+0.71 and mπr(3S1)=3.71-0.31+0.28-0.35+0.28. These values are consistent with the two-nucleon system exhibiting Wigner's supermultiplet symmetry, which becomes exact in the limit of large Nc. In both spin channels, the phase shifts change sign at higher momentum, near the start of the t-channel cut, indicating that the nuclear interactions have a repulsive core even at the SU(3)-symmetric point.

General gauge mediation in five dimensions