Macroscopic electric field inside water-filled biological nanopores.
Gutiérrez, Silvia Acosta; Bodrenko, Igor; Scorciapino, Mariano Andrea; Ceccarelli, Matteo
2016-03-23
Multi-drug resistance bacteria are a challenging problem of contemporary medicine. This is particularly critical for Gram-negative bacteria, where antibiotics are hindered by the outer membrane to reach internal targets. Here more polar antibiotics make use of nanometric water-filled channels to permeate inside. We present in this work a computational all-atom approach, using water as a probe, for the calculation of the macroscopic electric field inside water-filled channels. The method allows one to compare not only different systems but also the same system under different conditions, such as pH and ion concentration. This provides a detailed picture of electrostatics in biological nanopores shedding more light on how the charged residues of proteins determine the electric field inside, and also how medium can tune it. These details are central to unveil the filtering mechanism behind the permeation of small polar molecules through nanometric water-filled channels. PMID:26931352
REACTOR CANAL AFTER IT HAS BEEN TILED. WATER FILLS CANAL ...
REACTOR CANAL AFTER IT HAS BEEN TILED. WATER FILLS CANAL PART WAY TO TOP. CAMERA FACES WEST. INL NEGATIVE NO. 3993-A. Unknown Photographer, 12/28/1951 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID
A water-filled radio frequency accelerating cavity
Faehl, R.J.; Keinigs, R.K.; Pogue, E.W.
1998-12-31
This is the final report of a one-year, Laboratory Directed Research and Development (LDRD) project at Los Alamos National Laboratory (LANL). The objective of this project was to study water-filled resonant cavities as a high-energy density source to drive high-current accelerator configurations. Basic considerations lead to the expectation that a dielectric-filled cavity should be able to store up to e/e{sub o} as much energy as a vacuum one with the same dimensions and thus be capable of accelerating a proportionately larger amount of charge before cavity depletion occurs. During this project, we confirmed that water-filled cavities with e/e{sub o} = 60-80 did indeed behave with the expected characteristics, in terms of resonant TM modes and cavity Q. We accomplished this result with numerical cavity eigenvalue codes; fully electromagnetic, two-dimensional, particle-in-cell codes; and, most significantly, with scaled experiments performed in water-filled aluminum cavities. The low-power experiments showed excellent agreement with the numerical results. Simulations of the high-field, high-current mode of operation indicated that charged-particle loss on the dielectric windows, which separate the cavity from the beamline, must be carefully controlled to avoid significant distortion of the axial fields.
Green, Daniel; Lawrence, Albion; McGreevy, John; Morrison, David R.; Silverstein, Eva; /SLAC /Stanford U., Phys. Dept.
2007-05-18
We show that string theory on a compact negatively curved manifold, preserving a U(1)b1 winding symmetry, grows at least b1 new effective dimensions as the space shrinks. The winding currents yield a ''D-dual'' description of a Riemann surface of genus h in terms of its 2h dimensional Jacobian torus, perturbed by a closed string tachyon arising as a potential energy term in the worldsheet sigma model. D-branes on such negatively curved manifolds also reveal this structure, with a classical moduli space consisting of a b{sub 1}-torus. In particular, we present an AdS/CFT system which offers a non-perturbative formulation of such supercritical backgrounds. Finally, we discuss generalizations of this new string duality.
Acoustic imaging in a water filled metallic pipe
Kolbe, W.F.; Turko, B.T.; Leskovar, B.
1984-04-01
A method is described for the imaging of the interior of a water filled metallic pipe using acoustical techniques. The apparatus consists of an array of 20 acoustic transducers mounted circumferentially around the pipe. Each transducer is pulsed in sequence, and the echos resulting from bubbles in the interior are digitized and processed by a computer to generate an image. The electronic control and digitizing system and the software processing of the echo signals are described. The performance of the apparatus is illustrated by the imaging of simulated bubbles consisting of thin walled glass spheres suspended in the pipe.
Acoustic Propagation in a Water-Filled Cylindrical Pipe
Sullivan, E J; Candy, J V
2003-06-01
This study was concerned with the physics of the propagation of a tone burst of high frequency sound in a steel water-filled pipe. The choice of the pulse was rather arbitrary, so that this work in no way can be considered as recommending a particular pulse form. However, the MATLAB computer codes developed in this study are general enough to carry out studies of pulses of various forms. Also, it should be pointed out that the codes as written are quite time consuming. A computation of the complete field, including all 5995 modes, requires several hours on a desktop computer. The time required by such computations as these is a direct consequence of the bandwidths, frequencies and sample rates employed. No attempt was made to optimize these codes, and it is assumed that much can be done in this regard.
NASA Astrophysics Data System (ADS)
Duff, M. J.; Lu, J. X.; Percacci, R.; Pope, C. N.; Samtleben, H.; Sezgin, E.
2015-12-01
Just as string T-duality originates from transforming field equations into Bianchi identities on the string worldsheet, so it has been suggested that M-theory U-dualities originate from transforming field equations into Bianchi identities on the membrane worldvolume. However, this encounters a problem unless the target space has dimension D = p + 1. We identify the problem to be the nonintegrability of the U-duality transformation assigned to the pull-back map. Just as a double geometry renders manifest the O (D , D) string T-duality, here we show in the case of the M2-brane in D = 3 that a generalized geometry renders manifest the SL (3) × SL (2) U-duality. In the case of M2-brane in D = 4, with and without extra target space coordinates, we show that only the GL (4 , R) ⋉R4 subgroup of the expected SL (5 , R) U-duality symmetry is realized.
Preliminary Study on Water Filled Tank Perforation by Rod Projectiles
NASA Astrophysics Data System (ADS)
Xiao, Xin-Ke; Guo, Zi-Tao; Mu, Zhong-Cheng; Zhang, Wei
2009-06-01
The effects of fluid structure interactions resulting from the impact of a fluid filled tank is of the interests for engineers from both the military and civilian field, where hydrodynamic-ram (HRAM) phenomena is well known. And it is believed HRAM is responsible for the vulnerability and the possible catastrophic failure of the whole tank. Thus HRAM is related to the majority concerns on this topic, where the targets were usually assumed to be thin. In order to investigate the influence of water on the crashworthiness of a tank with relatively thick walls, 3 ballistic shots on the water filled tank with two 3 mm 2A12 aluminum plates as front and back target and 4 shots on the tank without any water by 12.7 mm rods were conducted. The failure patterns were indentified from the tests and the difference in the failure mechanism was further studied by a series of detailed numerical simulations on the corresponding tests in hydro-code AUTODYN-2D by using both the coupled Lagrange-Euler technology and the SPH method. And also, the challenge of numerical simulation in this field is addressed.
Water filling and electric field-induced enhancement in the mechanical property of carbon nanotubes.
Ye, H F; Zheng, Y G; Zhang, Z Q; Chen, Z; Zhang, H W
2015-01-01
The effects of water filling and electric field on the mechanical property of carbon nanotubes (CNTs) are investigated with molecular dynamics simulations. The simulation results indicate that the water filling and electric field could enhance the elastic modulus but reduce the Poisson's ratio of the CNTs. As for the buckling behaviors, a significant enhancement could be observed in the yield stress and average post-buckling stress of the CNTs. In particular, the enhancement in the yield stress induced by the water filling and electric field could be even higher than that resulted from the solid filling. Moreover, a transition mechanism from the rod instability to shell buckling is shown to explain the nonmonotonic variation of yield stress, and the critical diameter can be tuned through filling the water molecules and applying the electric field. The present findings provide a valuable route for the optimized design and application of the nanoscale functional devices based on the water-filled CNTs. PMID:26621767
Lalakulich, O.; Leitner, T.; Buss, O.; Mosel, U.; Praet, Ch.; Jachowicz, N.; Ryckebusch, J.
2009-11-25
A phenomenological study of Bloom-Gilman duality is performed in electron and neutrino scattering on nuclei. In the resonance region the structure functions are calculated within the phenomenological models of Ghent and Giessen groups, where only the resonance contribution is taken into account, and the background one is neglected. Structure functions F{sub 2} in the resonance region are compared with the DIS ones, extracted directly from the experimental data. The results show, that within the models considered the Bloom-Gilman duality does not work well for nuclei: the integrated strength in the resonance region is considerably lower than in the DIS one.
Supersymmetry and gravitational duality
Argurio, Riccardo; Dehouck, Francois; Houart, Laurent
2009-06-15
We study how the supersymmetry algebra copes with gravitational duality. As a playground, we consider a charged Taub-Newman-Unti-Tamburino(NUT) solution of D=4, N=2 supergravity. We find explicitly its Killing spinors, and the projection they obey provides evidence that the dual magnetic momenta necessarily have to appear in the supersymmetry algebra. The existence of such a modification is further supported using an approach based on the Nester form. In the process, we find new expressions for the dual magnetic momenta, including the NUT charge. The same expressions are then rederived using gravitational duality.
Brown, T. W.
2011-04-15
The same complex matrix model calculates both tachyon scattering for the c=1 noncritical string at the self-dual radius and certain correlation functions of operators which preserve half the supersymmetry in N=4 super-Yang-Mills theory. It is dual to another complex matrix model where the couplings of the first model are encoded in the Kontsevich-like variables of the second. The duality between the theories is mirrored by the duality of their Feynman diagrams. Analogously to the Hermitian Kontsevich-Penner model, the correlation functions of the second model can be written as sums over discrete points in subspaces of the moduli space of punctured Riemann surfaces.
Luminescence properties of individual empty and water-filled single-walled carbon nanotubes.
Cambré, Sofie; Santos, Silvia M; Wenseleers, Wim; Nugraha, Ahmad R T; Saito, Riichiro; Cognet, Laurent; Lounis, Brahim
2012-03-27
The influence of water filling on the photoluminescence (PL) properties of SWCNTs is studied by ensemble and single-molecule PL spectroscopy. Red-shifted PL and PL excitation spectra are observed upon water filling for 16 chiralities and can be used to unambiguously distinguish empty SWCNTs from filled ones. The effect of water filling on the optical transitions is well-reproduced by a continuum dielectric constant model previously developed to describe the influence of the nanotube outer environment. Empty nanotubes display narrower luminescence lines and lower inhomogeneous broadening, signatures of reduced extrinsic perturbations. The radial breathing mode phonon sideband is clearly observed in the PL spectrum of small diameter empty tubes, and a strong exciton-phonon coupling is measured for this vibration. Biexponential PL decays are observed for empty and water-filled tubes, and only the short-living component is influenced by the water filling. This may be attributed to a shortening of the radiative lifetime of the bright state by the inner dielectric environment. PMID:22314108
Water filling and electric field-induced enhancement in the mechanical property of carbon nanotubes
Ye, H. F.; Zheng, Y. G.; Zhang, Z. Q.; Chen, Z.; Zhang, H. W.
2015-01-01
The effects of water filling and electric field on the mechanical property of carbon nanotubes (CNTs) are investigated with molecular dynamics simulations. The simulation results indicate that the water filling and electric field could enhance the elastic modulus but reduce the Poisson’s ratio of the CNTs. As for the buckling behaviors, a significant enhancement could be observed in the yield stress and average post-buckling stress of the CNTs. In particular, the enhancement in the yield stress induced by the water filling and electric field could be even higher than that resulted from the solid filling. Moreover, a transition mechanism from the rod instability to shell buckling is shown to explain the nonmonotonic variation of yield stress, and the critical diameter can be tuned through filling the water molecules and applying the electric field. The present findings provide a valuable route for the optimized design and application of the nanoscale functional devices based on the water-filled CNTs. PMID:26621767
Simple Model of a Rolling Water-Filled Bottle on an Inclined Ramp
ERIC Educational Resources Information Center
Lin, Shihao; Hu, Naiwen; Yao, Tianchen; Chu, Charles; Babb, Simona; Cohen, Jenna; Sangiovanni, Giana; Watt, Summer; Weisman, Danielle; Klep, James; Walecki, Wojciech J.; Walecki, Eve S.; Walecki, Peter S.
2015-01-01
We investigate a water-filled bottle rolling down an incline and ask the following question: is a rolling bottle better described by a model ignoring all internal motion where the bottle is approximated by a material point sliding down an incline, or is it better described by a rigid solid cylinder rolling down the incline without skidding? The…
Quantitative wave-particle duality
NASA Astrophysics Data System (ADS)
Qureshi, Tabish
2016-07-01
The complementary wave and particle character of quantum objects (or quantons) was pointed out by Niels Bohr. This wave-particle duality, in the context of the two-slit experiment, is here described not just as two extreme cases of wave and particle characteristics, but in terms of quantitative measures of these characteristics, known to follow a duality relation. A very simple and intuitive derivation of a closely related duality relation is presented, which should be understandable to the introductory student.
The Structure of the Yeast Plasma Membrane SNARE Complex Reveals Destabilizing Water Filled Cavities
Strop, P.; Kaiser, S.E.; Vrljic, M.; Brunger, A.T.
2009-05-26
Soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) proteins form a complex that leads to membrane fusion between vesicles, organelles, and plasma membrane in all eukaryotic cells. We report the 1.7{angstrom} resolution structure of the SNARE complex that mediates exocytosis at the plasma membrane in the yeast Saccharomyces cerevisiae. Similar to its neuronal and endosomal homologues, the S. cerevisiae SNARE complex forms a parallel four-helix bundle in the center of which is an ionic layer. The S. cerevisiae SNARE complex exhibits increased helix bending near the ionic layer, contains water-filled cavities in the complex core, and exhibits reduced thermal stability relative to mammalian SNARE complexes. Mutagenesis experiments suggest that the water-filled cavities contribute to the lower stability of the S. cerevisiae complex.
Trachenko, K.; Brazhkin, V. V.
2013-01-01
Liquids flow, and in this sense are close to gases. At the same time, interactions in liquids are strong as in solids. The combination of these two properties is believed to be the ultimate obstacle to constructing a general theory of liquids. Here, we adopt a new approach: instead of focusing on the problem of strong interactions, we zero in on the relative contributions of vibrational and diffusional motion. We show that liquid energy and specific heat are given, to a very good approximation, by their vibrational contributions as in solids over almost entire range of relaxation time in which liquids exist as such, and demonstrate that this result is consistent with liquid entropy exceeding solid entropy. Our analysis therefore reveals an interesting duality of liquids not hitherto known: they are close to solids from the thermodynamic perspective and to flowing gases. We discuss several implications of this result. PMID:23851971
NASA Astrophysics Data System (ADS)
Allen, Theodore J.
1993-04-01
We examine the issue of duality both in electrodynamics and in Kalb-Ramond scalar axion systems. In D space-time dimensions the dual abelian theories of ( p -1)- and ( D - p - 1)-form potentials have vacua classified by the dimensions of the cohomology spaces Hp - 1(( D - 1) M) or HD - p -( (D - 1)M) , respectively. The vacua are characterized by topological charges which are expectation values for generalized "Wilson loop" operators around non-trivial cycles. In certain instances the vacua exhibit a theta angle parametrization much as in QCD. The relation of axionic hair and discrete gauge hair is analyzed in the topologically massive Kalb-Ramond theory. If there are no fundamental strings in the theory, axionic charge is replaced by an irrelevant vacuum angle.
Shear Weakening due to Drainge from Water-Filled Crevasses Along the Margins of Jakobshavn ISBRÆ
NASA Astrophysics Data System (ADS)
Lampkin, D. J.; Parizek, B. R.; Larour, E. Y.; Seroussi, H. L.; Morlighem, M.
2014-12-01
Several marine-terminating outlet glaciers on the Greenland Ice Sheet have undergone dynamic thinning, acceleration, and retreat, largely driven by ocean-ice interactions at the glacier terminus. Commensurate with these changes, surface melt rates are also increasing, resulting in enhanced runoff and infiltration known to influence regional ice velocity and mass flux. In particular, Jakobshavn Isbræ has experienced some of the most dramatic changes relative to the other major outlet glaciers largely responsible for Greenland's contribution to sea level rise. The fast-flowing trunk of Jakobshavn Isbræ is well within the ablation zone and is exposed to significant accumulated runoff and drainage from water-filled crevasses within the shear margins during the summer. The impact of drainage from these structures on Jakobshavn's response to terminus instability is not well understood. There are seven major water-filled crevasse regions along the margins, with the largest demonstrating potential drainage volume on order of that from large supraglacial lakes. This effort explores the impact of meltwater injection on shear-margin weakening. Meltwater can reduce lateral drag through enhanced sliding due to distributed basal lubrication or reduced ice viscosity due to cryo-hyrologic warming. The finite-element Ice Sheet System Model (ISSM) was used to evaluate the impact of meltwater input into the shear margins on basal sliding and ice stiffness. Ratios of misfit between modeled and measured velocity for inversions of basal friction and ice viscosity show a shift from basal friction-to-viscosity dominated conditions from the winter to the summer, at locations where water-filled crevasses exist. Forward models were perturbed to evaluate the magnitude of shear weakening due to enhanced sliding versus changes in ice hardness.
Electrical breakdown of a bubble in a water-filled capillary
Bruggeman, P.J.; Leys, C.A.; Vierendeels, J. A.
2006-06-01
In this Communication, the electrical breakdown of a static bubble in a water-filled capillary generated in a dc electrical field is studied. We present experimental results which indicate that the liquid layer between capillary and bubble wall can have an important influence on the breakdown mechanism of the bubble. The breakdown electrical field (atmospheric pressure) without a liquid layer in a (vapor) bubble is 18 kV/cm. When a liquid layer is present, the electrical breakdown of an air bubble is observed at electrical fields typically two times smaller. Local plasma formation is observed in this case possibly due to bubble deformation.
NASA Astrophysics Data System (ADS)
Anderson, Kevin
2015-12-01
Delivery of palatable 2 °C mitigation scenarios depends on speculative negative emissions or changing the past. Scientists must make their assumptions transparent and defensible, however politically uncomfortable the conclusions.
A study of vibroacoustic coupling between a pump and attached water-filled pipes.
Li, Bilong; Hodkiewicz, Melinda; Pan, Jie
2007-02-01
This paper presents a model for the vibroacoustical behavior of a pump coupled with water-filled pipes. Coupling between (a) the pump and the inlet and outlet pipes, and (b) the pipe wall and the fluid contained in the pipe, is investigated through analytical modeling and numerical simulation. In the model, the pump is represented by a rigid body supported by multiple elastic mounts, and the inlet and outlet pipes by two semi-infinite water-filled pipes. The vibration characteristics of the coupled system under the excitation of mechanical forces and fluid-borne forces at the pump are calculated. The results enhance our understanding about how the input mechanical and fluid excitation energy at the pump is transmitted to the pipes and how to relate the piping vibroacoustical response to the excitations at the pump. This study assists in predicting dynamic stress in pipes for given excitations at the pump, and in developing methods to identify the nature (fluid or mechanical) of the excitation forces at the pump using the vibration and dynamic pressure measurements on the pump/pipe system. PMID:17348514
España, Aubrey L; Williams, Kevin L; Plotnick, Daniel S; Marston, Philip L
2014-07-01
Understanding the physics governing the interaction of sound with targets in an underwater environment is essential to improving existing target detection and classification algorithms. To illustrate techniques for identifying the key physics, an examination is made of the acoustic scattering from a water-filled cylindrical shell. Experiments were conducted that measured the acoustic scattering from a water-filled cylindrical shell in the free field, as well as proud on a sand-water interface. Two modeling techniques are employed to examine these acoustic scattering measurements. The first is a hybrid 2-D/3-D finite element (FE) model, whereby the scattering in close proximity to the target is handled via a 2-D axisymmetric FE model, and the subsequent 3-D propagation to the far field is determined via a Helmholtz integral. This model is characterized by the decomposition of the fluid pressure and its derivative in a series of azimuthal Fourier modes. The second is an analytical solution for an infinitely long cylindrical shell, coupled with a simple approximation that converts the results to an analogous finite length form function. Examining these model results on a mode-by-mode basis offers easy visualization of the mode dynamics and helps distinguish the different physics driving the target response. PMID:24993199
Self-duality in Euclidean supergravity
NASA Astrophysics Data System (ADS)
Obrien, G. M.; Tchrakian, D. H.
1985-01-01
The compatibility conditions for curvatures satisfying self-duality (Hawking, 1978) and double-duality (Hehl et al., 1978) ansaetze in the theory of vacuum (Euclidean) supergravity and for the double-duality ansatz in Minkowski theory are investigated theoretically. It is found that the equations of motion of Euclidean supergravity admit solutions with self-dual curvature which correspond to nontrivial field configurations, and that the double-duality ansatz leads to nontrival configurations in both Euclidean and Minkowski cases.
Two-octave supercontinuum generation in a water-filled photonic crystal fiber.
Bethge, J; Husakou, A; Mitschke, F; Noack, F; Griebner, U; Steinmeyer, G; Herrmann, J
2010-03-15
Supercontinuum generation in a water-filled photonic crystal fiber is reported. By only filling the central hollow core of this fiber with water, the fiber properties are changed such that the air cladding provides broadband guiding. Using a pump wavelength of 1200 nm and few-microjoule pump pulses, the generation of supercontinua with two-octave spectral coverage from 410 to 1640 nm is experimentally demonstrated. Numerical simulations confirm these results, revealing a transition from a soliton-induced mechanism to self-phase modulation dominated spectral broadening with increasing pump power. Compared to supercontinua generated in glass core photonic fibers, the liquid core supercontinua show a higher degree of coherence, and the larger mode field area and the higher damage threshold of the water core enable significantly higher pulse energies of the white light pulses, ranging up to 0.39microJ. PMID:20389646
Seismic Source Characteristics of Nuclear Explosions in Water-filled Cavities
NASA Astrophysics Data System (ADS)
Murphy, J. R.; Sultanov, D. D.; Rimer, N.; Barker, B. W.
- During the period from 1975 to 1979, the former Soviet Union conducted a series a six nuclear explosions in a water-filled cavity in salt which was created in 1968 by a tamped 27kt explosion at a depth of 597m at the Azgir test site at the north end of the Caspian Sea. Broadband, near-regional seismic data recorded from these tests have been processed and analyzed in an attempt to characterize the seismic source characteristics of these explosions and assess their relevance to the cavity decoupling evasion scenario. The results of these analyses indicate that the explosions in the water-filled cavity were not decoupled, but rather show evidence of enhanced seismic coupling with respect to that which would be expected from tamped explosions of the same yields in salt. Theoretical finite difference simulations of these tests have been conducted in which the complex, nonlinear interactions between the shock effects in both the water and surrounding salt medium have been explicitly modeled. The results of these simulations indicate that the most prominent yield dependent features of the observed seismic source functions can be largely explained by the dynamic interactions between the expanding and contracting steam bubbles generated by the explosions in water and the shock-wave reflections from the cavity wall. More specifically, it has been found that the shock-wave reflection from the cavity wall retards the expansion of the steam bubble in a yield dependent fashion relative to that expected in the open ocean, resulting in a smaller maximum bubble radius and a shorter bubble oscillation period.
NASA Astrophysics Data System (ADS)
Slavnov, D. A.
2015-07-01
The problem of wave-particle duality is considered within the framework of the algebraic approach. Contrary to the widespread belief, we demonstrate that wave-particle duality can be reconciled with the assumption that there exists some local physical reality determining the results of local measurements. A number of quantum experiments—double-slit electron scattering, Wheeler's delayed choice experiment, the past of photons passed through the interferometer—are discussed using the concept of locality. A clear physical interpretation of these experiments that does not contradict classical concepts is provided.
Reference duality and representation duality in information geometry
NASA Astrophysics Data System (ADS)
Zhang, Jun
2015-01-01
Classical information geometry prescribes, on the parametric family of probability functions Mθ: (i) a Riemannian metric given by the Fisher information; (ii) a pair of dual connections (giving rise to the family of α-connections) that preserve the metric under parallel transport by their joint actions; and (iii) a family of (non-symmetric) divergence functions (α-divergence) defined on Mθ × Mθ, which induce the metric and the dual connections. The role of α parameter, as used in α-connection and in α-embedding, is not commonly differentiated. For instance, the case with α = ±1 may refer either to dually-flat (e- or m-) connections or to exponential and mixture families of density functions. Here we illuminate that there are two distinct types of duality in information geometry, one concerning the referential status of a point (probability function, normalized or denormalized) expressed in the divergence function ("reference duality") and the other concerning the representation of probability functions under an arbitrary monotone scaling ("representation duality"). They correspond to, respectively, using α as a mixture parameter for constructing divergence functions or as a power exponent parameter for monotone embedding of probability functions. These two dualities are coupled into referential-representational biduality for manifolds of denormalized probability functions with α-Hessian structure (i.e, transitively flat α-geometry) and for manifolds induced from homogeneous divergence functions with (α,β)-parameters but one-parameter family of (α ṡ β)-connections.
NASA Astrophysics Data System (ADS)
Yoshida, Eiichi; Wada, Akira; Karasawa, Naoki
2016-07-01
We generated a supercontinuum from a selectively water-filled photonic crystal fiber (PCF) for enhancement in the visible spectral region using an optical pulse from a Ti:sapphire oscillator at 804 nm. We prepared a 7-cm-long fused silica PCF, where the holes adjacent to the central core were filled with water, using a UV-curable adhesive to close holes selectively before filling holes with water by capillary force. Compared with that of the PCF without water, the group velocity dispersion curve of the selectively water-filled PCF became flatter near 800 nm and the intensity in the visible spectral region of the supercontinuum became higher and more uniform. The spectra simulated using the calculated dispersion properties of the selectively water-filled PCF showed good agreement with the experimental spectra.
Visualizing water-filled versus embolized status of xylem conduits by desktop x-ray microtomography
2013-01-01
Background The hydraulic conductivity of the stem is a major factor limiting the capability of trees to transport water from the soil to transpiring leaves. During drought conditions, the conducting capacity of xylem can be reduced by some conduits being filled with gas, i.e. embolized. In order to understand the dynamics of embolism formation and repair, considerable attention has been given to developing reliable and accurate methods for quantifying the phenomenon. In the past decade, non-destructive imaging of embolism formation in living plants has become possible. Magnetic resonance imaging has been used to visualize the distribution of water within the stem, but in most cases it is not possible to resolve individual cells. Recently, high-resolution synchrotron x-ray microtomography has been introduced as a tool to visualize the water contents of individual cells in vivo, providing unprecedented insight into the dynamics of embolism repair. We have investigated the potential of an x-ray tube -based microtomography setup to visualize and quantify xylem embolism and embolism repair in water-stressed young saplings and shoot tips of Silver and Curly birch (Betula pendula and B. pendula var. carelica). Results From the microtomography images, the water-filled versus gas-filled status of individual xylem conduits can be seen, and the proportion of stem cross-section that consists of embolized tissue can be calculated. Measuring the number of embolized vessels in the imaged area is a simple counting experiment. In the samples investigated, wood fibers were cavitated in a large proportion of the xylem cross-section shortly after watering of the plant was stopped, but the number of embolized vessels remained low several days into a drought period. Under conditions of low evaporative demand, also refilling of previously embolized conduits was observed. Conclusions Desktop x-ray microtomography is shown to be an effective method for evaluating the water-filled versus
Fluid-structure interaction in water-filled thin pipes of anisotropic composite materials
NASA Astrophysics Data System (ADS)
You, Jeong Ho; Inaba, K.
2013-01-01
The effects of elastic anisotropy in piping materials on fluid-structure interaction are studied for water-filled carbon-fiber reinforced thin plastic pipes. When an impact is introduced to water in a pipe, there are two waves traveling at different speeds. A primary wave corresponding to a breathing mode of pipe travels slowly and a precursor wave corresponding to a longitudinal mode of pipe travels fast. An anisotropic stress-strain relationship of piping materials has been taken into account to describe the propagation of primary and precursor waves in the carbon-fiber reinforced thin plastic pipes. The wave speeds and strains in the axial and hoop directions are calculated as a function of carbon-fiber winding angles and compared with the experimental data. As the winding angle increases, the primary wave speed increases due to the increased stiffness in the hoop direction, while the precursor wave speed decreases. The magnitudes of precursor waves are much smaller than those of primary waves so that the effect of precursor waves on the deformation of pipe is not significant. The primary wave generates the hoop strain accompanying the opposite-signed axial strain through the coupling compliance of pipe. The magnitude of hoop strain induced by the primary waves decreases with increasing the winding angle due to the increased hoop stiffness of pipe. The magnitude of axial strain is small at low and high winding angles where the coupling compliance is small.
Motion of a free cylinder inside a rotating water-filled drum
NASA Astrophysics Data System (ADS)
Hernández, R. H.; Vial, A.; Barraud, C.
2015-08-01
We report experimental results on the motion and levitation of a freely to-move heavy cylinder, of constant diameter and varying mass, inside a water-filled drum rotating around its horizontal axis. The resulting flow field and the cylinder dynamics were determined with the aid of flow visualizations and particle image velocimetry methods. The spatial tracking of the inner cylinder was done with the aid of Fourier cross correlation methods. The steady bulk flow field created by the drum rotation generated forces that make the inner cylinder to counter-rotate without contact with the drum walls. Testing different cylinder masses and rotating drum frequencies has shown that there exists a range of stable spatial positions of the inner cylinder describing an angular segment inside the drum flow. The cylinder frequency can be set to zero if we increase the drum frequency beyond a threshold value. Increasing the drum frequency produces a stronger secondary flow circulation which is the key-mechanism responsible of the counter-rotating cylinder frequency. At this point, the inner cylinder levitates with a constant separation from the drum walls close to half of its diameter. Tests on heavy hollow cylinders revealed that the fluid filling the cylinder remains at rest while the cylinder was under levitation with zero rotation frequency.
A comparative molecular analysis of water-filled limestone sinkholes in north-eastern Mexico.
Sahl, Jason W; Gary, Marcus O; Harris, J Kirk; Spear, John R
2011-01-01
Sistema Zacatón in north-eastern Mexico is host to several deep, water-filled, anoxic, karstic sinkholes (cenotes). These cenotes were explored, mapped, and geochemically and microbiologically sampled by the autonomous underwater vehicle deep phreatic thermal explorer (DEPTHX). The community structure of the filterable fraction of the water column and extensive microbial mats that coat the cenote walls was investigated by comparative analysis of small-subunit (SSU) 16S rRNA gene sequences. Full-length Sanger gene sequence analysis revealed novel microbial diversity that included three putative bacterial candidate phyla and three additional groups that showed high intra-clade distance with poorly characterized bacterial candidate phyla. Limited functional gene sequence analysis in these anoxic environments identified genes associated with methanogenesis, sulfate reduction and anaerobic ammonium oxidation. A directed, barcoded amplicon, multiplex pyrosequencing approach was employed to compare ∼100,000 bacterial SSU gene sequences from water column and wall microbial mat samples from five cenotes in Sistema Zacatón. A new, high-resolution sequence distribution profile (SDP) method identified changes in specific phylogenetic types (phylotypes) in microbial mats at varied depths; Mantel tests showed a correlation of the genetic distances between mat communities in two cenotes and the geographic location of each cenote. Community structure profiles from the water column of three neighbouring cenotes showed distinct variation; statistically significant differences in the concentration of geochemical constituents suggest that the variation observed in microbial communities between neighbouring cenotes are due to geochemical variation. PMID:20738374
Response of a water-filled spherical vessel to an internal explosion
Lewis, M.W.; Wilson, T.L.
1997-06-01
Many problems of interest to the defense community involve fluid-structure interaction (FSI). Such problems include underwater blast loading of structures, bubble dynamics and jetting around structures, and hydrodynamic ram events. These problems may involve gas, fluid, and solid dynamics, nonlinear material behavior, cavitation, reaction kinetics, material failure, and nonlinearity that is due to varying geometry and contact conditions within a structure or between structures. Here, the authors model the response of a water-filled, thick-walled, spherical steel vessel to an internal explosion of 30 grams of C-4 with FSI2D--a two-dimensional coupled finite element and finite volume hydrodynamics code. The gas phase detonation products were modeled with a Becker-Kistiakowsky-Wilson high-explosive equation of state. Predictions from a fully coupled model were compared to experimental results in the form of strain gauge traces. Agreement was reasonably good. Additionally, the calculation was run in an uncoupled mode to understand the importance of fluid-structure interaction in this problem. The uncoupled model results in an accumulation of nonphysical energy in the vessel.
Thiyahuddin, M I; Thambiratnam, D P; Gu, Y T
2014-10-01
Portable water-filled barriers (PWFBs) are roadside appurtenances that prevent vehicles from penetrating into temporary construction zones on roadways. PWFBs are required to satisfy the strict regulations for vehicle re-direction in tests. However, many of the current PWFBs fail to re-direct the vehicle at high speeds due to the inability of the joints to provide appropriate stiffness. The joint mechanism hence plays a crucial role in the performance of a PWFB system at high speed impacts. This paper investigates the desired features of the joint mechanism in a PWFB system that can re-direct vehicles at high speeds, while limiting the lateral displacement to acceptable limits. A rectangular "wall" representative of a 30m long barrier system was modeled and a novel method of joining adjacent road barriers was introduced through appropriate pin-joint connections. The impact response of the barrier "wall" and the vehicle was obtained and the results show that a rotational stiffness of 3000kNm/rad at the joints seems to provide the desired features of the PWFB system to re-direct impacting vehicles and restrict the lateral deflection. These research findings will be useful to safety engineers and road barrier designers in developing a new generation of PWFBs for increased road safety. PMID:24887591
Simple Model of a Rolling Water-Filled Bottle on an Inclined Ramp
NASA Astrophysics Data System (ADS)
Lin, Shihao; Hu, Naiwen; Yao, Tianchen; Chu, Charles; Babb, Simona; Cohen, Jenna; Sangiovanni, Giana; Watt, Summer; Weisman, Danielle; Klep, James; Walecki, Wojciech J.; Walecki, Eve S.; Walecki, Peter S.
2015-12-01
We investigate a water-filled bottle rolling down an incline and ask the following question: is a rolling bottle better described by a model ignoring all internal motion where the bottle is approximated by a material point sliding down an incline, or is it better described by a rigid solid cylinder rolling down the incline without skidding? The measurements presented here represent a special case of similar experiments described by K.A. Jackson et al. (see Ref. 1 and references within). There exists also a report by Kagan describing the motion of soda cans rolling on an incline. In our case we investigate motion of the fully filled bottle. We demonstrate that within accuracy of our experiment the motion of the bottle can be described by a simple "frictionless water" model. The analysis of the dynamics of the bodies sliding and rolling on a ramp is a standard component of introductory physics classes, and a required component of the Advanced Placement (AP) Physics curriculum.
Morphodynamics of a granular bed in a water-filled cylinder subjected to perturbed oscillations
NASA Astrophysics Data System (ADS)
Duran-Matute, Matias; van Gorp, Thijs; van Heijst, Gertjan
2015-11-01
We study experimentally the morphodynamics of a granular bed at the bottom of an oscillating water-filled cylinder. The granules are translucent PMMA particles with a typical size of 2mm. The bed thickness is measured in real time using a light attenuation technique. As shown already by previous work, the bed remains flat close to the center of the cylinder, and radial ripples form at outer radii. The size of the inner flat region and the number or ripples depend on the frequency and amplitude of the cylinder's oscillation. In the present work, we are interested in the dynamics and control of the bed forms when the primary sinusoidal signal of the oscillation is perturbed by adding a second sinusoidal signal with a relatively small amplitude, a different frequency, and a phase lag. Varying the parameters of the secondary signal results in a signal that can be asymmetric or modulated, for example. These properties translate into the bed producing simple behavior like the propagation of the ripples at a constant speed or more complex behavior like the time dependent coarsening and thinning of the ripples. This research is funded by NWO (the Netherlands) through the VENI grant 863.13.022.
The Characteristic of Porous Charges on a Base of a Water-Filled RDX Powder
NASA Astrophysics Data System (ADS)
Valiano, Georgy; Yankovskiy, Boris; Milyavskiy, Vladimir; Borodina, Tatiana
2011-06-01
A detonation velocity of a condensed RDX linearly depends on density at a range of 1,0-1,8 g/cm3. These charges are porous if the density of RDX monocrystal is 1,806 g/cm3. The state of porous charge can be characterized by the packing density. It can be rising, if RDX powder will be mixed with water for deciding technological problems. It is necessary to be able to predict characteristics of such charges. Charges on a base of a water-filled RDX powder with air inclusions can be described by three parameters: a density of a charge, packing density of RDX powder and RDX mass fraction. Last two parameters are independent parameters of a mix. We have designed a nomogram for definition of mutual communication of three quantities: velocity of a detonation, density of packing of RDX powder and its mass fraction in a mix. To check up correctness of a prelegends of a nomogram, we have carried out measurement of a detonation velocity of porous water-contained RDX charges. We prepared charges on a base of RDX powder which has consisted of particles with a size 80-220 mcm. We was changing RDX mass fraction of charges in a range 0,6-1,0 and a packing density of RDX powder in a range of 1,0-1,4 g/cm3. The disorder of experimental data concerning the nomogram data did not exceed basically of 3 percent.
The impact of tungsten long rod penetrators into water filled targets
Wilson, L.T.; Dickinson, D.L.; Hertel, E.S. Jr.
1998-02-01
Twelve experiments were conducted to determine the effect of water filled targets on the penetration of tungsten long rods in terms of their residual mass and integrity. CTH hydrocode calculations were performed for each of the experiments to ensure that the erosion and breakup of the tungsten projectiles could be accurately reproduced. The CTH hydrocode predictions correlation well with the experimental results in most cases. Only 8% of the variance is unexplained. The slip interface between the rod and water was approximated in one of two ways: (1) using the CTH BLINT option in 2-D or (2) using a standard Eulerian mixed cells treatment. Results indicate that a 3-D BLINT algorithm is critical to predicting rod residual lengths. The authors were unable to reproduce rod fracture that occurred in every experiment where the water column exceeded 25 cm in length. The authors feel that this is due to a change in rod material properties during penetration, and continue to investigate the issue.
Estimation of water-filled and air-filled porosity in the unsaturated zone, Yucca Mountain, Nevada
Nelson, Philip H.
1993-01-01
The responses of density and dielectric logs are formulated in terms if the matrix properties, air-filled porosity and water-filled porosity. Porosity values obtained from logs from borehole USW G-2 are in reasonable agreement with estimates from core determinations.
Quark-Hadron Duality in Electron Scattering
W. Melnitchouk
2000-09-01
Quark-hadron duality addresses some of the most fundamental issues in strong interaction physics, in particular the nature of the transition from the perturbative to non-perturbative regions of QCD. I summarize recent developments in quark-hadron duality in lepton-hadron scattering, and outline how duality can be studied at future high-luminosity facilities such as Jefferson Lab at 12 GeV, or an electron-hadron collider such as EPIC.
Quark-hadron duality in structure functions
Wally Melnitchouk
2011-09-01
We review recent progress in the study of quark-hadron duality in electron–nucleon structure functions. New developments include insights into the local aspects of duality obtained using truncated moments of structure functions, which allow duality-violating higher-twist contributions to be identified in individual resonance regions. Preliminary studies of pion electropro-duction have also showed the first glimpses of duality in semi-inclusive cross sections, which if confirmed would greatly expand the scope of constraining the flavor and spin dependence of parton distributions.
Geochemistry and Hydrogeology of Water-Filled Sinkholes at Bitter Lake NWR, Roswell, NM
NASA Astrophysics Data System (ADS)
Premo, Z. E.; Crossey, L. J.
2008-12-01
Bitter Lake NWR in southeast (Roswell) New Mexico is located at the convergence of the Pecos River and the surface discharge region in the Roswell Artesian Basin (shallow alluvial aquifer and carbonate aquifer). The Refuge hosts approximately 50 water-filled sinkholes, which each support a unique and diverse aquatic ecosystem. An initial survey of water chemistries indicates that each sink has a unique chemical identity and neutral to alkaline pH. Sinkholes are filled by one or more artesian springs, groundwater seepage and possible hydrothermal water sources. We present results of water and gas analyses of 10 representative sinkholes, sampled during spring and summer, 2008. Analytical results, including major ions, metals (arsenic, selenium, iron), and gas chemistries are compared with monitoring well data from wells found to the north of the Refuge, along the Pecos River, and to the west, along the Pecos Slope - the regional aquifer recharge area. Well samples representative of regional groundwater provide potential end member perspectives for sources of sinkhole waters. Samples were collected incrementally from the surface to sinkhole floor to profile the limnological structure and to assess chemical variation and mixing through the water column. A sonde was deployed to measure and record physical parameters. Results of the analysis are used to describe the geochemical mixing that is occurring within the sinks. As each sink behaves as an independent unit, those separated by less than 10 meters can have dramatic variability in chemical signature and biological influence. For example, among the 29 sinks sampled during the initital survey, chloride concentrations range from 1.912x10-3 to 1.405 mol/kg; sulfate from 7.204x10-4 to 0.1364 mol/kg; and fluoride from 3.579x10-4 to 3.453x10-3 mol/kg. Along the Pecos Slope, groundwater chloride concentrations increase from less than 1.410x10-3 mol/kg near the major recharge area in the Sacramento Mountains to 0.141 mol
Duality between coordinates and Dirac field
NASA Astrophysics Data System (ADS)
Abdalla, M. C. B.; Gadelha, A. L.; Vancea, I. V.
2000-07-01
The duality between the Cartesian coordinates on the Minkowski space-time and the Dirac field is investigated. Two distinct possibilities to define this duality are shown to exist. In both cases, the equations satisfied by prepotentials are of second order.
Managing Dualities in Planned Change Initiatives
ERIC Educational Resources Information Center
Barge, J. Kevin; Lee, Michael; Maddux, Kristy; Nabring, Richard; Townsend, Bryan
2008-01-01
Dualities play an important role in creating the conditions for change and managing planned change initiatives. Building on Seo, Putnam, and Bartunek's (2003) work, this study focuses on the dualities associated with managing change processes. A case study of a planned change process called the Circle of Prosperity Initiative, a multi-stakeholder…
S-duality and helicity amplitudes
NASA Astrophysics Data System (ADS)
Colwell, Kitran; Terning, John
2016-03-01
We examine interacting Abelian theories at low energies and show that holomorphically normalized photon helicity amplitudes transform into dual amplitudes under SL(2, {Z} ) as modular forms with weights that depend on the number of positive and negative helicity photons and on the number of internal photon lines. Moreover, canonically normalized helicity amplitudes transform by a phase, so that even though the amplitudes are not duality invariant, their squares are duality invariant. We explicitly verify the duality transformation at one loop by comparing the amplitudes in the case of an electron and the dyon that is its SL(2, {Z} ) image, and extend the invariance of squared amplitudes order by order in perturbation theory. We demonstrate that S-duality is a property of all low-energy effective Abelian theories with electric and/or magnetic charges and see how the duality generically breaks down at high energies.
Supersymmetry: Compactification, flavor, and dualities
NASA Astrophysics Data System (ADS)
Heidenreich, Benjamin Jones
N = 1 gauge theory dualities relating different world-volume gauge theories of D3 branes probing an orientifold singularity. We argue that these dualities originate from the S-duality of type IIB string theory, much like electromagnetic dualities of N = 4 gauge theories.
NASA Astrophysics Data System (ADS)
Obers, N. A.; Pioline, B.
1999-09-01
This work is intended as a pedagogical introduction to M-theory and to its maximally supersymmetric toroidal compactifications, in the frameworks of 11D supergravity, type II string theory and M(atrix) theory. U-duality is used as the main tool and guideline in uncovering the spectrum of BPS states. We review the 11D supergravity algebra and elementary 1/2-BPS solutions, discuss T-duality in the perturbative and non-perturbative sectors from an algebraic point of view, and apply the same tools to the analysis of U-duality at the level of the effective action and of the BPS spectrum, with a particular emphasis on Weyl and Borel generators. We derive the U-duality multiplets of BPS particles and strings, U-duality invariant mass formulae for 1/2- and 1/4-BPS states for general toroidal compactifications on skew tori with gauge backgrounds, and U-duality multiplets of constraints for states to preserve a given fraction of supersymmetry. A number of mysterious states are encountered in D≤3, whose existence is implied by T-duality and 11D Lorentz invariance. We then move to the M(atrix) theory point of view, give an introduction to Discrete Light-Cone Quantization (DLCQ) in general and DLCQ of M-theory in particular. We discuss the realization of U-duality as electric-magnetic dualities of the Matrix gauge theory, display the Matrix gauge theory BPS spectrum in detail, and discuss the conjectured extended U-duality group in this scheme.
The Hydrochemical Evolution of Water-Filled Sinkholes at Bitter Lake NWR, Roswell, NM
NASA Astrophysics Data System (ADS)
Premo, E.; Crossey, L. J.
2013-12-01
Bitter Lake National Wildlife Refuge in Roswell, NM houses one of the most ecologically significant wetlands in the US-SW including approximately 52 water-filled sinkholes each supporting a unique biological assemblage, including several endangered and endemic species (e.g., Pecos pupfish and Noel's amphipod, respectively). Forming in the karst landscape adjacent to the Pecos River where the regional dual-aquifer system discharges through a network of springs and seeps, these sinkholes are recharged by saline groundwater that is subject to anthropogenic withdrawals for irrigation and hydrocarbon production and chemically altered by a complex series of evaporation-precipitation reactions after discharge. This study investigates the hydrochemical differences among these sinkholes while considering the evolutionary processes affecting water column structure, geochemical mixing and ecological sustainability. Two major sampling suites, pre- and post-irrigation, yielded waters from 1.0m increments along the water columns of 10 representative sinkholes. Samples were analyzed for major ions, stable isotopes [δ18O, δD ], and dissolved gases; PHREEQc was used to model mineral saturation and speciation. An in-situ mineral precipitation experiment provided growth rate and mineral morphological (SEM) data. Source water is chemically similar to shallow springs found at the Refuge (Sago Spring). Sinkholes exhibit bimodal water column structure (well-mixed or stratified) organized in response to water density (with ~1.035 g/cm3 forming the modal transition threshold). By measuring the density, TDS or conductivity at sinkhole surface it is possible to predict modality of water column structure. Sinkhole waters - regardless of depth or season - fall along a common isotopic evaporation trajectory (δ D = 3.387*δ18O - 19.38), and adopt a Na-Cl chemical endmember facies. Driven primarily by physical sinkhole geometry (e.g., depth and surface area), sinkhole water follows a
Ring wormholes via duality rotations
NASA Astrophysics Data System (ADS)
Gibbons, Gary W.; Volkov, Mikhail S.
2016-09-01
We apply duality rotations and complex transformations to the Schwarzschild metric to obtain wormhole geometries with two asymptotically flat regions connected by a throat. In the simplest case these are the well-known wormholes supported by phantom scalar field. Further duality rotations remove the scalar field to yield less well known vacuum metrics of the oblate Zipoy-Voorhees-Weyl class, which describe ring wormholes. The ring encircles the wormhole throat and can have any radius, whereas its tension is always negative and should be less than -c4 / 4 G. If the tension reaches the maximal value, the geometry becomes exactly flat, but the topology remains non-trivial and corresponds to two copies of Minkowski space glued together along the disk encircled by the ring. The geodesics are straight lines, and those which traverse the ring get to the other universe. The ring therefore literally produces a hole in space. Such wormholes could perhaps be created by negative energies concentrated in toroidal volumes, for example by vacuum fluctuations.
Duality symmetries in string theory
Nunez, Carmen A.
1999-10-25
The search for a unified theory of quantum gravity and gauge interactions leads naturally to string theory. This field of research has received a revival of interest after the discovery of duality symmetries in recent years. We present a self contained account of some non-perturbative aspects of string theory which have been recently understood. The spectrum and interactions of the five consistent superstring theories in ten dimensions are recollected and the fundamental principles underlying this initial stage in the construction of the theory are briefly reviewed. We next discuss some evidences that these apparently different superstrings are just different aspects of one unique theory. The key to this development is given by the non-perturbative duality symmetries which have modified and improved our understanding of string dynamics in many ways. In particular, by relating the fundamental objects of one theory to solitons of another theory, they have unraveled the presence of extended objects in the theory which stand on an equal footing with strings. We introduce these higher dimensional objects, named D-branes, and discuss applications of D-brane physics.
Three-slit interference: A duality relation
NASA Astrophysics Data System (ADS)
Asad Siddiqui, Mohd; Qureshi, Tabish
2015-08-01
The issue of interference and which-way information is addressed in the context of three-slit interference experiments. A new path distinguishability DQ is introduced, based on unambiguous quantum state discrimination. An inequality connecting the interference visibility and path distinguishability, V + {2D_Qover 3- D_Q} ≤ 1, is derived which puts a bound on how much fringe visibility and which-way information can be simultaneously obtained. It is argued that this bound is tight. For two-slit interference, we derive a new duality relation which reduces to Englert's duality relation and the Greenberger-Yasin duality relation, in different limits.
Direct mediation, duality and unification
NASA Astrophysics Data System (ADS)
Abel, Steven; Khoze, Valentin V.
2008-11-01
It is well-known that in scenarios with direct gauge mediation of supersymmetry breaking the messenger fields significantly affect the running of Standard Model couplings and introduce Landau poles which are difficult to avoid. Among other things, this appears to remove any possibility of a meaningful unification prediction and is often viewed as a strong argument against direct mediation. We propose two ways that Seiberg duality can circumvent this problem. In the first, which we call ``deflected-unification'', the SUSY-breaking hidden sector is a magnetic theory which undergoes a Seiberg duality to an electric phase. Importantly, the electric version has fewer fundamental degrees of freedom coupled to the MSSM compared to the magnetic formulation. This changes the β-functions of the MSSM gauge couplings so as to push their Landau poles above the unification scale. We show that this scenario is realised for recently suggested models of gauge mediation based on a metastable SCQD-type hidden sector directly coupled to MSSM. The second possibility for avoiding Landau poles, which we call ``dual-unification'', begins with the observation that, if the mediating fields fall into complete SU(5) multiplets, then the MSSM+messengers exhibits a fake unification at unphysical values of the gauge couplings. We show that, in known examples of electric/magnetic duals, such a fake unification in the magnetic theory reflects a real unification in the electric theory. We therefore propose that the Standard Model could itself be a magnetic dual of some unknown electric theory in which the true unification takes place. This scenario maintains the unification prediction (and unification scale) even in the presence of Landau poles in the magnetic theory below the GUT scale. We further note that this dual realization of grand unification can explain why Nature appears to unify, but the proton does not decay.
Duality cascade in brane inflation
Bean, Rachel; Chen Xingang; Hailu, Girma; Henry Tye, S-H; Xu Jiajun E-mail: xgchen@mit.edu E-mail: tye@lepp.cornell.edu
2008-03-15
We show that brane inflation is very sensitive to tiny sharp features in extra dimensions, including those in the potential and in the warp factor. This can show up as observational signatures in the power spectrum and/or non-Gaussianities of the cosmic microwave background radiation (CMBR). One general example of such sharp features is a succession of small steps in a warped throat, caused by Seiberg duality cascade using gauge/gravity duality. We study the cosmological observational consequences of these steps in brane inflation. Since the steps come in a series, the prediction of other steps and their properties can be tested by future data and analysis. It is also possible that the steps are too close to be resolved in the power spectrum, in which case they may show up only in the non-Gaussianity of the CMB temperature fluctuations and/or EE polarization. We study two cases. In the slow-roll scenario, where steps appear in the inflaton potential, the sensitivity of brane inflation to the height and width of the steps is increased by several orders of magnitude compared to that in previously studied large field models. In the IR DBI scenario, where steps appear in the warp factor, we find that the glitches in the power spectrum caused by these sharp features are generally small or even unobservable, but associated distinctive non-Gaussianity can be large. Together with its large negative running of the power spectrum index, this scenario clearly illustrates how rich and different a brane inflationary scenario can be when compared to generic slow-roll inflation. Such distinctive stringy features may provide a powerful probe of superstring theory.
Fermionic T-Duality a Snapshot Review
NASA Astrophysics Data System (ADS)
Ó Colgáin, Eoin
2012-11-01
Through a self-dual mapping of the geometry AdS5 ×S5, fermionic T-duality provides a beautiful geometric interpretation of hidden symmetries for scattering amplitudes in N = 4 super-Yang-Mills. Starting with Green-Schwarz sigma-models, we consolidate developments in this area into this small review. In particular, we discuss the translation of fermionic T-duality into the supergravity fields via pure spinor formalism and show that a general class of fermionic transformations can be identified directly in the supergravity. In addition to discussing fermionic T-duality for the geometry AdS4 × ℂP3, dual to N = 6 ABJM theory, we review work on other self-dual geometries. Finally, we present a short round-up of studies with a formal interest in fermionic T-duality.
Maxwell Duality, Lorentz Invariance, and Topological Phase
NASA Technical Reports Server (NTRS)
Dowling, J.; Williams, C.; Franson, J.
1999-01-01
We discuss the Maxwell electromagnetic duality relations between the Aharonov-Bohm, Aharonov-Casher, and He-McKellar-Wilkens topological phases, which allows a unified description of all three phenomena.
Can (electric-magnetic) duality be gauged?
Bunster, Claudio; Henneaux, Marc
2011-02-15
There exists a formulation of the Maxwell theory in terms of two vector potentials, one electric and one magnetic. The action is then manifestly invariant under electric-magnetic duality transformations, which are rotations in the two-dimensional internal space of the two potentials, and local. We ask the question: Can duality be gauged? The only known and battle-tested method of accomplishing the gauging is the Noether procedure. In its decanted form, it amounts to turning on the coupling by deforming the Abelian gauge group of the free theory, out of whose curvatures the action is built, into a non-Abelian group which becomes the gauge group of the resulting theory. In this article, we show that the method cannot be successfully implemented for electric-magnetic duality. We thus conclude that, unless a radically new idea is introduced, electric-magnetic duality cannot be gauged. The implication of this result for supergravity is briefly discussed.
Quark-Hadron Duality in Electron Scattering
Wally Melnitchouk; Rolf Ent; Cynthia Keppel
2004-08-01
The duality between partonic and hadronic descriptions of physical phenomena is one of the most remarkable features of strong interaction physics. A classic example of this is in electron-nucleon scattering, in which low-energy cross sections, when averaged over appropriate energy intervals, are found to exhibit the scaling behavior expected from perturbative QCD. We present a comprehensive review of data on structure functions in the resonance region, from which the global and local aspects of duality are quantified, including its flavor, spin and nuclear medium dependence. To interpret the experimental findings, we discuss various theoretical approaches which have been developed to understand the microscopic origins of quark-hadron duality in QCD. Examples from other reactions are used to place duality in a broader context, and future experimental and theoretical challenges are identified.
Duality, Entropy and ADM Mass in Supergravity
Cerchiai, Bianca L.; Ferrara, Sergio; Marrani, Alessio; Zumino, Bruno
2009-02-23
We consider the Bekenstein-Hawking entropy-area formula in four dimensional extended ungauged supergravity and its electric-magnetic duality property. Symmetries of both"large" and"small" extremal black holes are considered, as well as the ADM mass formula for N=4 and N=8 supergravity, preserving different fraction of supersymmetry. The interplay between BPS conditions and duality properties is an important aspect of this investigation.
Duality, entropy, and ADM mass in supergravity
Cerchiai, Bianca L.; Zumino, Bruno; Ferrara, Sergio; Marrani, Alessio
2009-06-15
We consider the Bekenstein-Hawking entropy-area formula in four dimensional extended ungauged supergravity and its electric-magnetic duality property. Symmetries of both 'large' and 'small' extremal black holes are considered, as well as the ADM mass formula for N=4 and N=8 supergravity, preserving different fraction of supersymmetry. The interplay between BPS conditions and duality properties is an important aspect of this investigation.
Diamond, S. Kjellsen, K.O.
2008-04-15
SEM examinations are reported of freshly-mixed and early age mortar specimens prepared by fast freezing in liquid nitrogen followed by epoxy impregnation, and of companion specimens of early aged mortars prepared conventionally. Freshly-mixed mortars reveal complex features that appear to influence subsequent development of the hardened state microstructure. In particular, layers of entirely water-filled space a few micrometers thick are found adjacent to many of the sand grain surfaces. After a few hours sparse deposits of calcium hydroxide crystals (and later C-S-H) are found within these layers, but the layers persist as recognizable features for at least 12 h. The layers are identically recognizable in both fast-frozen and conventionally-prepared specimens. Another feature found in freshly-mixed mortars is the existence of patchy local areas of sparsely-packed and other areas of densely-packed cement particles.
General Quantum Interference Principle and Duality Computer
NASA Astrophysics Data System (ADS)
Long, Gui-Lu
2006-05-01
In this article, we propose a general principle of quantum interference for quantum system, and based on this we propose a new type of computing machine, the duality computer, that may outperform in principle both classical computer and the quantum computer. According to the general principle of quantum interference, the very essence of quantum interference is the interference of the sub-waves of the quantum system itself. A quantum system considered here can be any quantum system: a single microscopic particle, a composite quantum system such as an atom or a molecule, or a loose collection of a few quantum objects such as two independent photons. In the duality computer, the wave of the duality computer is split into several sub-waves and they pass through different routes, where different computing gate operations are performed. These sub-waves are then re-combined to interfere to give the computational results. The quantum computer, however, has only used the particle nature of quantum object. In a duality computer, it may be possible to find a marked item from an unsorted database using only a single query, and all NP-complete problems may have polynomial algorithms. Two proof-of-the-principle designs of the duality computer are presented: the giant molecule scheme and the nonlinear quantum optics scheme. We also propose thought experiment to check the related fundamental issues, the measurement efficiency of a partial wave function.
Master space, Hilbert series and Seiberg duality
NASA Astrophysics Data System (ADS)
Forcella, Davide; Hanany, Amihay; Zaffaroni, Alberto
2009-07-01
We analyze the action of Toric (Seiberg) duality on the combined mesonic and baryonic moduli space of quiver gauge theories obtained from D3 branes at Calabi-Yau singularities. We analyze in particular the structure of the master space, the complete moduli space for one brane, for different toric phases of a given singularity. We show that the Hilbert Series for the largest component of the master space of different phases is the same, when refined with all the non anomalous charges. This reflects the fact that the quiver gauge theories associated with different phases are related by Seiberg duality when the number of branes is greater than one.
Altruistic duality in evolutionary game theory
NASA Astrophysics Data System (ADS)
Cheon, Taksu
2003-11-01
A game-theoretic dynamical model of social preference and enlightened self-interest is formulated. Existence of symmetry and duality in the game matrices with altruistic social preference is revealed. The model quantitatively describes the dynamical evolution of altruism in prisoner's dilemma and the regime change in prey-predator dynamics.
Global-local duality in eternal inflation
Bousso, Raphael; Yang, I-S.
2009-12-15
We prove that the light-cone time cutoff on the multiverse defines the same probabilities as a causal patch with initial conditions in the longest-lived metastable vacuum. This establishes the equivalence of two measures of eternal inflation which naively appear very different (though both are motivated by holography). The duality can be traced to an underlying geometric relation which we identify.
On the universe's cybernetics duality behavior
NASA Astrophysics Data System (ADS)
Feria, Erlan H.
2015-05-01
Universal cybernetics is the study of control and communications in living and non-living systems. In this paper the universal cybernetics duality principle (UCDP), first identified in control theory in 1978 and expressing a cybernetic duality behavior for our universe, is reviewed. The review is given on the heels of major prizes given to physicists for their use of mathematical dualities in solving intractable problems in physics such as those of cosmology's `dark energy', an area that according to a recent New York Times article has become "a cottage industry in physics today". These dualities are not unlike those of our UCDP that are further enhanced with physical dualities. For instance, in 2008 the UCDP guided us to the derivation of the laws of retention in physics as the space-penalty dual of the laws of motion in physics, including the dark energy thought responsible for the observed increase of the volume of our Universe as it ages. The UCDP has also guided us to the discovery of significant results in other fields such as: 1) in matched processors for quantized control with applications in the modeling of central nervous system (CNS) control mechanisms; 2) in radar designs where the discovery of latency theory, the time-penalty dual of information-theory, has led us to high-performance radar solutions that evade the use of `big data' in the form of SAR imagery of the earth; and 3) in unveiling biological lifespan bounds where the life-expectancy of an organism is sensibly predicted through lingerdynamics, the identified time-penalty dual of thermodynamics, which relates its adult lifespan to either: a. the ratio of its body size to its nutritional consumption rate; or b. its specific heat-capacity; or c. the ratio of its nutritional consumption rate energy to its entropic volume energy, a type of dark energy that is consistent with the observed decrease in the mass density of the organism as it ages.
Yan, Xiliang; Fan, Jianfen; Yu, Yi; Xu, Jian; Zhang, Mingming
2015-05-26
Molecular dynamics simulations have been performed to investigate the transport properties of a single Ca(2+), K(+), and Na(+) in a water-filled transmembrane cyclic peptide nanotube (CPNT). Two transmembrane CPNTs, i.e., 8×(WL)n=4,5/POPE (with uniform lengths but various radii), were applied to clarify the dependence of ionic transport properties on the channel radius. A huge energy barrier keeps Ca(2+) out of the octa-CPNT, while Na(+) and K(+) can be trapped in two CPNTs. The dominant electrostatic interaction of a cation with water molecules leads to a high distribution of channel water around the cation and D-defects in the first and last gaps, and significantly reduces the axial diffusion of channel water. Water-bridged interactions were mostly found between the artificially introduced Ca(2+) and the framework of the octa-CPNT, and direct coordinations with the tube wall mostly occur for K(+) in the octa-CPNT. A cation may drift rapidly or behave lazily in a CPNT. K(+) behaves most actively and can visit the whole deca-CPNT quickly. The first solvation shells of Ca(2+) and Na(+) are basically saturated in two CPNTs, while the hydration of K(+) is incomplete in the octa-CPNT. The solvation structure of Ca(2+) in the octa-CPNT is most stable, while that of K(+) in the deca-CPNT is most labile. Increasing the channel radius induces numerous interchange attempts between the first-shell water molecules of a cation and the ones in the outer region, especially for the K(+) system. PMID:25894098
Kawakami, Yoshikazu; Menkes, Harold A.; DuBois, Arthur B.
1970-01-01
A water-filled body plethysmograph was constructed to measure gas exchange in man. As compared to an air-filled plethysmograph, its advantages were greater sensitivity, less thermal drift, and no change from adiabatic to isothermal conditions after a stepwise change of pressure. When five subjects were completely immersed within it and were breathing to the ambient atmosphere, they had a normal heart rate, oxygen consumption, CO2 output, and functional residual capacity. Pulmonary capillary blood flow ([unk]Qc) during and after Valsalva and Mueller maneuvers was calculated from measurements of N2O uptake. Control measurements of [unk]Qc were 2.58 liters/min per m2 at rest and 3.63 liters/min per m2 after moderate exercise. During the Valsalva maneuver at rest (intrapulmonary pressure: 24, SD 3.0, mm Hg), [unk]Qc decreased from a control of 2.58, SD 0.43, liters/min per m2 to 1.62, SD 0.26, liters/min per m2 with a decrease in pulmonary capillary stroke volume from a control of 42.4, SD 8.8, ml/stroke per m2 to 25.2, SD 5.5, ml/stroke per m2. After release of the Valsalva, there was an overshoot in [unk]Qc averaging +0.78, SD 0.41, liter/min per m2 accompanied by a significant increase in heart rate. Similar changes occurred during and after the Valsalva following moderate exercise. During the Mueller maneuver at rest and after exercise, [unk]Qc, heart rate, and central stroke volume did not change significantly. Images PMID:5422025
Unraveling duality violations in hadronic tau decays
Cata, Oscar; Cata, Oscar; Golterman, Maarten; Peris, Santiago
2008-03-03
There are some indications from recent determinations of the strong coupling constant alpha_s and the gluon condensate that the Operator Product Expansion may not be accurate enough to describe non-perturbative effects in hadronic tau decays. This breakdown of the Operator Product Expansion is usually referred to as being due to"Duality Violations." With the help of a physically motivated model, we investigate these duality violations. Based on this model, we argue how they may introduce a non-negligible systematic error in the current analysis, which employs finite-energy sum rules with pinched weights. In particular, this systematic effect might affect the precision determination of alpha_s from tau decays. With a view to a possible future application to real data, we present an alternative method for determining the OPE coefficients that might help estimating, and possibly even reducing, this systematic error.
Conceptual Aspects of Gauge/Gravity Duality
NASA Astrophysics Data System (ADS)
De Haro, Sebastian; Mayerson, Daniel R.; Butterfield, Jeremy N.
2016-07-01
We give an introductory review of gauge/gravity duality, and associated ideas of holography, emphasising the conceptual aspects. The opening sections gather the ingredients, viz. anti-de Sitter spacetime, conformal field theory and string theory, that we need for presenting, in Sect. 5, the central and original example: Maldacena's AdS/CFT correspondence. Sections 6 and 7 develop the ideas of this example, also in applications to condensed matter systems, QCD, and hydrodynamics. Sections 8 and 9 discuss the possible extensions of holographic ideas to de Sitter spacetime and to black holes. Section 10 discusses the bearing of gauge/gravity duality on two philosophical topics: the equivalence of physical theories, and the idea that spacetime, or some features of it, are emergent.
Dimensional-duality and Its Lie Groups
NASA Astrophysics Data System (ADS)
Sinha, Nilotpal
2009-01-01
For a claim to a dimensional duality, we consider here that, the relativity is depending on a "double-fold" complex number for locally dense fourth axis within an enveloping 3D-space. This dimensional duality has been made here for locally dense m-dimensional geometry within n-space, for m > n, if every axis of m-space is dimensional-dual to its enveloping n-space. This locally dense m-dimensional geometry describes a reflexive complex function, viz., "transfusion" transformation, which establishes that, Lie group U(2) is the simply connected 1 to 2 enveloping group of SO(3, 1) within D-dual spaces only. Again, using the weight vectors, it is found that, there exists a SU(4) group, which may be a symmetry group for gravitons.
Duality and holographic renormalization group flows
NASA Astrophysics Data System (ADS)
Halmagyi, Nicholas
This thesis contains a detailed study of holographic renormalization group flows in An quiver gauge theories. The flows considered are two fold. Firstly I consider flows generated by mass terms for the adjoint chiral superfields, these flows have conformal fixed point in the ultraviolet as well as the infrared. Two well known flows in this class are the Pilch-Warner flow and the Klebanov-Witten flow, which as deformations of the UV theory lie in the untwisted sector and twisted sector respectively. There is also known to be flows which mix the twisted and untwisted sectors. We study this whole family of flows using field theory methods combined with their M-theory construction. In particular I elaborate on the duality group which acts on this whole family of flows and a subgroup of the full duality group is identified directly in the field theory as Seiberg duality. The structure of the long sought after IIB supergravity solution to the Klebanov-Witten flow is provided, the entire flow is a metric on the singular conifold which we provide up to the solution of one non-linear p.d.e. Further, the IIB string is solved in the Penrose limit of the Pilch-Warner solution. Secondly, we consider flows which are confining in the infrared the same duality group which acts on this RG-flows mentioned above, also acts of this family of flows. A certain universal behaviour is discovered on this large family of flows and is attributed to certain properties of the affine Weyl group.
Duality of coordinates and matter fields in curved spacetime
NASA Astrophysics Data System (ADS)
De Andrade, M. A.; Vancea, I. V.
2000-02-01
We show that there exists a duality between the local coordinates and the solutions of the Klein-Gordon equation in curved spacetime in the same sense as in the Minkowski spacetime. However, the duality in curved spacetime does not have the same generality as in flat spacetime and it holds only if the system satisfies certain constraints. We derive these constraints and the basic equations of duality and discuss the implications in the quantum theory.
Duality analysis on random planar lattices.
Ohzeki, Masayuki; Fujii, Keisuke
2012-11-01
The conventional duality analysis is employed to identify a location of a critical point on a uniform lattice without any disorder in its structure. In the present study, we deal with the random planar lattice, which consists of the randomized structure based on the square lattice. We introduce the uniformly random modification by the bond dilution and contraction on a part of the unit square. The random planar lattice includes the triangular and hexagonal lattices in extreme cases of a parameter to control the structure. A modern duality analysis fashion with real-space renormalization is found to be available for estimating the location of the critical points with a wide range of the randomness parameter. As a simple test bed, we demonstrate that our method indeed gives several critical points for the cases of the Ising and Potts models and the bond-percolation thresholds on the random planar lattice. Our method leads to not only such an extension of the duality analyses on the classical statistical mechanics but also a fascinating result associated with optimal error thresholds for a class of quantum error correction code, the surface code on the random planar lattice, which is known as a skillful technique to protect the quantum state. PMID:23214752
Real weights, bound states and duality orbits
NASA Astrophysics Data System (ADS)
Marrani, Alessio; Riccioni, Fabio; Romano, Luca
2016-01-01
We show that the duality orbits of extremal black holes in supergravity theories with symmetric scalar manifolds can be derived by studying the stabilizing subalgebras of suitable representatives, realized as bound states of specific weight vectors of the corresponding representation of the duality symmetry group. The weight vectors always correspond to weights that are real, where the reality properties are derived from the Tits-Satake diagram that identifies the real form of the Lie algebra of the duality symmetry group. Both 𝒩 = 2 magic Maxwell-Einstein supergravities and the semisimple infinite sequences of 𝒩 = 2 and 𝒩 = 4 theories in D = 4 and 5 are considered, and various results, obtained over the years in the literature using different methods, are retrieved. In particular, we show that the stratification of the orbits of these theories occurs because of very specific properties of the representations: in the case of the theory based on the real numbers, whose symmetry group is maximally noncompact and therefore all the weights are real, the stratification is due to the presence of weights of different lengths, while in the other cases it is due to the presence of complex weights.
Hutchinson's duality: The once and future niche
Colwell, Robert K.; Rangel, Thiago F.
2009-01-01
The duality between “niche” and “biotope” proposed by G. Evelyn Hutchinson provides a powerful way to conceptualize and analyze biogeographical distributions in relation to spatial environmental patterns. Both Joseph Grinnell and Charles Elton had attributed niches to environments. Attributing niches, instead, to species, allowed Hutchinson's key innovation: the formal severing of physical place from environment that is expressed by the duality. In biogeography, the physical world (a spatial extension of what Hutchinson called the biotope) is conceived as a map, each point (or cell) of which is characterized by its geographical coordinates and the local values of n environmental attributes at a given time. Exactly the same n environmental attributes define the corresponding niche space, as niche axes, allowing reciprocal projections between the geographic distribution of a species, actual or potential, past or future, and its niche. In biogeographical terms, the realized niche has come to express not only the effects of species interactions (as Hutchinson intended), but also constraints of dispersal limitation and the lack of contemporary environments corresponding to parts of the fundamental niche. Hutchinson's duality has been used to classify and map environments; model potential species distributions under past, present, and future climates; study the distributions of invasive species; discover new species; and simulate increasingly more realistic worlds, leading to spatially explicit, stochastic models that encompass speciation, extinction, range expansion, and evolutionary adaptation to changing environments. PMID:19805163
Action for twisted self-duality
NASA Astrophysics Data System (ADS)
Bunster, Claudio; Henneaux, Marc
2011-06-01
One may write the Maxwell equations in terms of two gauge potentials, one electric and one magnetic, by demanding that their field strengths should be dual to each other. This requirement is the condition of twisted self-duality. It can be extended to p-forms in spacetime of D dimensions, and it survives the introduction of a variety of couplings among forms of different rank, and also to spinor and scalar fields, which emerge naturally from supergravity. In this paper we provide a systematic derivation of the action principle, whose equations of motion are the condition of twisted self-duality. The derivation starts from the standard Maxwell action, extended to include the aforementioned couplings, and proceeds via the Hamiltonian formalism through the resolution of Gauss’s law. In the pure Maxwell case we recover in this way an action that had been postulated by other authors, through an ansatz based on an action given earlier by us for untwisted self-duality. When Chern-Simons couplings are included, our action is, however, new. The derivation from the standard extended Maxwell action implies of course that the theory is Lorentz invariant and can be locally coupled to gravity. Nevertheless we include a direct compact Hamiltonian proof of these properties, which is based on the surface-deformation algebra. The symmetry in the dependence of the action on the electric and magnetic variables is manifest, since they appear as canonical conjugates. Spacetime covariance, although present, is not manifest.
Duality analysis on random planar lattices
NASA Astrophysics Data System (ADS)
Ohzeki, Masayuki; Fujii, Keisuke
2012-11-01
The conventional duality analysis is employed to identify a location of a critical point on a uniform lattice without any disorder in its structure. In the present study, we deal with the random planar lattice, which consists of the randomized structure based on the square lattice. We introduce the uniformly random modification by the bond dilution and contraction on a part of the unit square. The random planar lattice includes the triangular and hexagonal lattices in extreme cases of a parameter to control the structure. A modern duality analysis fashion with real-space renormalization is found to be available for estimating the location of the critical points with a wide range of the randomness parameter. As a simple test bed, we demonstrate that our method indeed gives several critical points for the cases of the Ising and Potts models and the bond-percolation thresholds on the random planar lattice. Our method leads to not only such an extension of the duality analyses on the classical statistical mechanics but also a fascinating result associated with optimal error thresholds for a class of quantum error correction code, the surface code on the random planar lattice, which is known as a skillful technique to protect the quantum state.
Gauge theory, topological strings, and S-duality
NASA Astrophysics Data System (ADS)
Kapustin, Anton
2004-09-01
We offer a derivation of the duality between the topological U(1) gauge theory on a Calabi-Yau 3-fold and the topological A-model on the same manifold. This duality was conjectured recently by Iqbal, Nekrasov, Okounkov, and Vafa. We deduce it from the S-duality of the IIB superstring. We also argue that the mirror version of this duality relates the topological B-model on a Calabi-Yau 3-fold and a topological sector of the Type IIA Little String Theory on the same manifold.
Local Quark-Hadron Duality in Electron Scattering
Wally Melnitchouk
2007-09-10
We present some recent developments in the study of quark-hadron duality in structure functions in the resonance region. To understand the workings of local duality we introduce the concept of truncated moments, which are used to describe the Q^2 dependence of specific resonance regions within a QCD framework.
T-Duality Simplifies Bulk-Boundary Correspondence
NASA Astrophysics Data System (ADS)
Mathai, Varghese; Thiang, Guo Chuan
2016-07-01
Recently, we introduced T-duality in the study of topological insulators. In this paper, we study the bulk-boundary correspondence for three phenomena in condensed matter physics, namely, the quantum Hall effect, the Chern insulator, and time reversal invariant topological insulators. In all of these cases, we show that T-duality trivializes the bulk-boundary correspondence.
Dualities in M-theory and Born-Infeld Theory
Brace, Daniel, M
2001-08-01
We discuss two examples of duality. The first arises in the context of toroidal compactification of the discrete light cone quantization of M-theory. In the presence of nontrivial moduli coming from the M-theory three form, it has been conjectured that the system is described by supersymmetric Yang-Mills gauge theory on a noncommutative torus. We are able to provide evidence for this conjecture, by showing that the dualities of this M-theory compactification, which correspond to T-duality in Type IIA string theory, are also dualities of the noncommutative supersymmetric Yang-Mills description. One can also consider this as evidence for the accuracy of the Matrix Theory description of M-theory in this background. The second type of duality is the self-duality of theories with U(1) gauge fields. After discussing the general theory of duality invariance for theories with complex gauge fields, we are able to find a generalization of the well known U(1) Born-Infeld theory that contains any number of gauge fields and which is invariant under the maximal duality group. We then find a supersymmetric extension of our results, and also show that our results can be extended to find Born-Infeld type actions in any even dimensional spacetime.
Spectral duality in integrable systems from AGT conjecture
NASA Astrophysics Data System (ADS)
Mironov, A.; Morozov, A.; Zenkevich, Y.; Zotov, A.
2013-03-01
We describe relationships between integrable systems with N degrees of freedom arising from the Alday-Gaiotto-Tachikawa conjecture. Namely, we prove the equivalence (spectral duality) between the N-cite Heisenberg spin chain and a reduced gl N Gaudin model both at classical and quantum level. The former one appears on the gauge theory side of the Alday-Gaiotto-Tachikawa relation in the Nekrasov-Shatashvili (and further the Seiberg-Witten) limit while the latter one is natural on the CFT side. At the classical level, the duality transformation relates the Seiberg-Witten differentials and spectral curves via a bispectral involution. The quantum duality extends this to the equivalence of the corresponding Baxter-Schrödinger equations (quantum spectral curves). This equivalence generalizes both the spectral self-duality between the 2 × 2 and N × N representations of the Toda chain and the famous Adams-Harnad-Hurtubise duality.
Duality in supersymmetric Yang-Mills theory
Peskin, M.E.
1997-02-01
These lectures provide an introduction to the behavior of strongly-coupled supersymmetric gauge theories. After a discussion of the effective Lagrangian in nonsupersymmetric and supersymmetric field theories, the author analyzes the qualitative behavior of the simplest illustrative models. These include supersymmetric QCD for N{sub f} < N{sub c}, in which the superpotential is generated nonperturbatively, N = 2 SU(2) Yang-Mills theory (the Seiberg-Witten model), in which the nonperturbative behavior of the effect coupling is described geometrically, and supersymmetric QCD for N{sub f} large, in which the theory illustrates a non-Abelian generalization of electric-magnetic duality. 75 refs., 12 figs.
Diffractive Scattering and Gauge/String Duality
Tan, Chung-I [Brown University, Providence, Rhode Island, United States
2009-09-01
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.
Spin Duality on the Neutron (^3He)
Solvignon, Patricia
2007-02-01
Thomas Jefferson National Accelerator Facility experiment E01-012 measured the 3He spin structure functions and virtual photon asymmetries in the resonance region in the momentum transfer range 1.0 < Q2 < 4.0 (GeV/c)2. Our date, when compared with existing deep inelastic scattering data, can be used to test quark-hadron duality in g1 and A1 for 3He and the neutron. Preliminary results for A{sub 1}{sup {sup 3}He} are presented, as well as some details about the experiment.
Quantum duality, unbounded operators, and inductive limits
Dosi, Anar
2010-06-15
In this paper, we investigate the inductive limits of quantum normed (or operator) spaces. This construction allows us to treat the space of all noncommutative continuous functions over a quantum domain as a quantum (or local operator) space of all matrix continuous linear operators equipped with S-quantum topology. In particular, we classify all quantizations of the polynormed topologies compatible with the given duality proposing a noncommutative Arens-Mackey theorem. Further, the inductive limits of operator spaces are used to introduce locally compact and locally trace class unbounded operators on a quantum domain and prove the dual realization theorem for an abstract quantum space.
Duality in a maximum generalized entropy model
NASA Astrophysics Data System (ADS)
Eguchi, Shinto; Komori, Osamu; Ohara, Atsumi
2015-01-01
This paper discusses a possible generalization for the maximum entropy principle. A class of generalized entropy is introduced by that of generator functions, in which the maximum generalized distribution model is explicitly derived including q-Gaussian distributions, Wigner semicircle distributions and Pareto distributions. We define a totally geodesic subspace in the total space of all probability density functions in a framework of information geometry. The model of maximum generalized entropy distributions is shown to be totally geodesic. The duality of the model and the estimation in the maximum generalized principle is elucidated to give intrinsic understandings from the point of information geometry.
ERIC Educational Resources Information Center
Storm, Paula; Kelly, Robert; deVries, Susann
2008-01-01
People and organizations are inherently political. Library workplace environments have zones of tension and dynamics just like any corporation, often leading to the formation of political camps. These different cliques influence productivity and work-related issues and, at worst, give meetings the feel of the Camp David negotiations. Politics are…
Liouville mode in gauge/gravity duality
NASA Astrophysics Data System (ADS)
Moskalets, Tatiana; Nurmagambetov, Alexei
2015-11-01
We establish solutions corresponding to AdS_4 static charged black holes with inhomogeneous two-dimensional horizon surfaces of constant curvature. Depending on the choice of the 2D constant curvature space, the metric potential of the internal geometry of the horizon satisfies the elliptic wave/elliptic Liouville equations. We calculate the charge diffusion and transport coefficients in the hydrodynamic limit of gauge/gravity duality and observe the exponential suppression in the diffusion coefficient and in the shear viscosity-per-entropy density ratio in the presence of an inhomogeneity on black hole horizons with planar, spherical, and hyperbolic geometry. We discuss the subtleties of the approach developed for a planar black hole with inhomogeneity distribution on the horizon surface in more detail and find, among others, a trial distribution function, which generates values of the shear viscosity-per-entropy density ratio falling within the experimentally relevant range. The solutions obtained are also extended to higher-dimensional AdS space. We observe two different DC conductivities in 4D and higher-dimensional effective strongly coupled dual media and formulate conditions under which the appropriate ratio of different conductivities is qualitatively the same as that observed in an anisotropic strongly coupled fluid. We briefly discuss ways of how the Liouville field could appear in condensed matter physics and outline prospects of further employing the gauge/gravity duality in CMP problems.
Fricke S-duality in CHL models
NASA Astrophysics Data System (ADS)
Persson, Daniel; Volpato, Roberto
2015-12-01
We consider four dimensional CHL models with sixteen spacetime supersymmetries obtained from orbifolds of type IIA superstring on K3× T 2 by a {Z}_N symmetry acting (possibly) non-geometrically on K3. We show that most of these models (in particular, for geometric symmetries) are self-dual under a weak-strong duality acting on the heterotic axio-dilaton modulus S by a "Fricke involution" S → -1 /NS. This is a novel symmetry of CHL models that lies outside of the standard SL(2,Z) -symmetry of the parent theory, heterotic strings on T 6. For self-dual models this implies that the lattice of purely electric charges is N-modular, i.e. isometric to its dual up to a rescaling of its quadratic form by N. We verify this prediction by determining the lattices of electric and magnetic charges in all relevant examples. We also calculate certain BPS-saturated couplings and verify that they are invariant under the Fricke S-duality. For CHL models that are not self-dual, the strong coupling limit is dual to type IIA compactified on {T}^6/{Z}_N , for some {Z}_N -symmetry preserving half of the spacetime supersymmetries.
Fricke S-duality in CHL models
Persson, Daniel; Volpato, Roberto
2015-12-23
In this study, we consider four dimensional CHL models with sixteen spacetime supersymmetries obtained from orbifolds of type IIA superstring on K3×T^{2} by a Z_{N} symmetry acting (possibly) non-geometrically on K3. We show that most of these models (in particular, for geometric symmetries) are self-dual under a weak-strong duality acting on the heterotic axio-dilaton modulus S by a “Fricke involution” S → -1/NS. This is a novel symmetry of CHL models that lies outside of the standard SL(2,Z)-symmetry of the parent theory, heterotic strings on T^{6}. For self-dual models this implies that the lattice of purely electric charges is N-modular, i.e. isometric to its dual up to a rescaling of its quadratic form by N. We verify this prediction by determining the lattices of electric and magnetic charges in all relevant examples. We also calculate certain BPS-saturated couplings and verify that they are invariant under the Fricke S-duality. For CHL models that are not self-dual, the strong coupling limit is dual to type IIA compactified on T^{6}/Z_{N}, for some Z_{N}-symmetry preserving half of the spacetime supersymmetries.
Fricke S-duality in CHL models
Persson, Daniel; Volpato, Roberto
2015-12-23
In this study, we consider four dimensional CHL models with sixteen spacetime supersymmetries obtained from orbifolds of type IIA superstring on K3×T2 by a ZN symmetry acting (possibly) non-geometrically on K3. We show that most of these models (in particular, for geometric symmetries) are self-dual under a weak-strong duality acting on the heterotic axio-dilaton modulus S by a “Fricke involution” S → -1/NS. This is a novel symmetry of CHL models that lies outside of the standard SL(2,Z)-symmetry of the parent theory, heterotic strings on T6. For self-dual models this implies that the lattice of purely electric charges is N-modular,more » i.e. isometric to its dual up to a rescaling of its quadratic form by N. We verify this prediction by determining the lattices of electric and magnetic charges in all relevant examples. We also calculate certain BPS-saturated couplings and verify that they are invariant under the Fricke S-duality. For CHL models that are not self-dual, the strong coupling limit is dual to type IIA compactified on T6/ZN, for some ZN-symmetry preserving half of the spacetime supersymmetries.« less
Duality between electric and magnetic black holes
NASA Astrophysics Data System (ADS)
Hawking, S. W.; Ross, Simon F.
1995-11-01
A number of attempts have recently been made to extend the conjectured S duality of Yang-Mills theory to gravity. Central to these speculations has been the belief that electrically and magnetically charged black holes, the solitons of quantum gravity, have identical quantum properties. This is not obvious, because, although duality is a symmetry of the classical equations of motion, it changes the sign of the Maxwell action. Nevertheless, we show that the chemical potential and charge projection that one has to introduce for electric but not magnetic black holes exactly compensate for the difference in action in the semiclassical approximation. In particular, we show that the pair production of electric black holes is not a runaway process, as one might think if one just went by the action of the relevant instanton. We also comment on the definition of the entropy in cosmological situations, and show that we need to be more careful when defining the entropy than we are in an asymptotically flat case.
Duality relations in the auxiliary field method
Silvestre-Brac, Bernard
2011-05-15
The eigenenergies {epsilon}{sup (N)}(m;{l_brace}n{sub i}, l{sub i{r_brace}}) of a system of N identical particles with a mass m are functions of the various radial quantum numbers n{sub i} and orbital quantum numbers l{sub i}. Approximations E{sup (N)}(m;Q) of these eigenenergies, depending on a principal quantum number Q({l_brace}n{sub i}, l{sub i{r_brace}}), can be obtained in the framework of the auxiliary field method. We demonstrate the existence of numerous exact duality relations linking quantities E{sup (N)}(m;Q) and E{sup (p)}(m';Q') for various forms of the potentials (independent of m and N) and for both nonrelativistic and semirelativistic kinematics. As the approximations computed with the auxiliary field method can be very close to the exact results, we show with several examples that these duality relations still hold, with sometimes a good accuracy, for the exact eigenenergies {epsilon}{sup (N)}(m;{l_brace}n{sub i}, l{sub i{r_brace}}).
Duality quantum computer and the efficient quantum simulations
NASA Astrophysics Data System (ADS)
Wei, Shi-Jie; Long, Gui-Lu
2016-03-01
Duality quantum computing is a new mode of a quantum computer to simulate a moving quantum computer passing through a multi-slit. It exploits the particle wave duality property for computing. A quantum computer with n qubits and a qudit simulates a moving quantum computer with n qubits passing through a d-slit. Duality quantum computing can realize an arbitrary sum of unitaries and therefore a general quantum operator, which is called a generalized quantum gate. All linear bounded operators can be realized by the generalized quantum gates, and unitary operators are just the extreme points of the set of generalized quantum gates. Duality quantum computing provides flexibility and a clear physical picture in designing quantum algorithms, and serves as a powerful bridge between quantum and classical algorithms. In this paper, after a brief review of the theory of duality quantum computing, we will concentrate on the applications of duality quantum computing in simulations of Hamiltonian systems. We will show that duality quantum computing can efficiently simulate quantum systems by providing descriptions of the recent efficient quantum simulation algorithm of Childs and Wiebe (Quantum Inf Comput 12(11-12):901-924, 2012) for the fast simulation of quantum systems with a sparse Hamiltonian, and the quantum simulation algorithm by Berry et al. (Phys Rev Lett 114:090502, 2015), which provides exponential improvement in precision for simulating systems with a sparse Hamiltonian.
Resch, Mária; Bella, Tamás
2013-04-21
In Hungary one can mostly find references to the psychological processes of politics in the writings of publicists, public opinion pollsters, philosophers, social psychologists, and political analysts. It would be still important if not only legal scientists focusing on political institutions or sociologist-politologists concentrating on social structures could analyse the psychological aspects of political processes; but one could also do so through the application of the methods of political psychology. The authors review the history of political psychology, its position vis-à-vis other fields of science and the essential interfaces through which this field of science, which is still to be discovered in Hungary, connects to other social sciences. As far as its methodology comprising psycho-biographical analyses, questionnaire-based queries, cognitive mapping of interviews and statements are concerned, it is identical with the psychiatric tools of medical sciences. In the next part of this paper, the focus is shifted to the essence and contents of political psychology. Group dynamics properties, voters' attitudes, leaders' personalities and the behavioural patterns demonstrated by them in different political situations, authoritativeness, games, and charisma are all essential components of political psychology, which mostly analyses psychological-psychiatric processes and also involves medical sciences by relying on cognitive and behavioural sciences. This paper describes political psychology, which is basically part of social sciences, still, being an interdisciplinary science, has several ties to medical sciences through psychological and psychiatric aspects. PMID:23587541
Nicholson, N.; Dowdy, E.J.; Holt, D.M.; Stump, C.J. Jr.
1982-05-13
A portable instrument for measuring induced Cerenkov radiation associated with irradiated nuclear fuel assemblies in a water-filled storage pond is disclosed. The instrument includes a photomultiplier tube and an image intensifier which are operable in parallel and simultaneously by means of a field lens assembly and an associated beam splitter. The image intensifier permits an operator to aim and focus the apparatus on a submerged fuel assembly. Once the instrument is aimed and focused, an illumination reading can be obtained with the photomultiplier tube. The instrument includes a lens cap with a carbon-14/phosphor light source for calibrating the apparatus in the field.
U-duality between NCOS theory and matrix theory
NASA Astrophysics Data System (ADS)
Hyun, Seungjoon
2001-03-01
We show that the NCOS (noncommutative open string) theories on torus T p ( p⩽5) are U-dual to matrix theory on torus with electric flux background. Under U-duality, the number of D-branes and the number of units of electric flux get interchanged. Furthermore, under the same U-duality the decoupling limit taken in the NCOS theory maps to the decoupling limit taken in the matrix theory, thus ensure the U-duality between those two class of theories. We consider the energy needed for Higgsing process and some bound states with finite energy and find agreements in both theories.
Towards reconciliation of several dualities in physician leadership.
Saxena, Anurag; Walker, Keith; Kraines, Gerry
2015-02-01
Leadership has a renewed focus in healthcare, and physicians are being increasingly involved in a range of leadership roles. The aim of this paper is to discuss several dualities that exert tensions at the systems and individual levels. Although oppositional, the common dualities of physician leadership are not mutually exclusive but represent a complex, dynamic and interdependent relationship, often coexisting with each other and exerting tensions in multiple dimensions. The authors contend that a dialectic understanding--instead of either/or or finding a middle ground--of the opposite poles of these dualities allows for generating meaningful leadership perspectives and choices. PMID:25947031
Towards Reconciliation of Several Dualities in Physician Leadership
Walker, Keith; Kraines, Gerry
2015-01-01
Leadership has a renewed focus in healthcare, and physicians are being increasingly involved in a range of leadership roles. The aim of this paper is to discuss several dualities that exert tensions at the systems and individual levels. Although oppositional, the common dualities of physician leadership are not mutually exclusive but represent a complex, dynamic and interdependent relationship, often coexisting with each other and exerting tensions in multiple dimensions. The authors contend that a dialectic understanding – instead of either/or or finding a middle ground – of the opposite poles of these dualities allows for generating meaningful leadership perspectives and choices. PMID:25947031
Duality linking standard and tachyon scalar field cosmologies
Avelino, P. P.; Bazeia, D.; Losano, L.; Oliveira, J. C. R. E.; Pavan, A. B.
2010-09-15
In this work we investigate the duality linking standard and tachyon scalar field homogeneous and isotropic cosmologies in N+1 dimensions. We determine the transformation between standard and tachyon scalar fields and between their associated potentials, corresponding to the same background evolution. We show that, in general, the duality is broken at a perturbative level, when deviations from a homogeneous and isotropic background are taken into account. However, we find that for slow-rolling fields the duality is still preserved at a linear level. We illustrate our results with specific examples of cosmological relevance, where the correspondence between scalar and tachyon scalar field models can be calculated explicitly.
NASA Astrophysics Data System (ADS)
Marqués, Diego; Nuñez, Carmen A.
2015-10-01
We construct an O( d, d) invariant universal formulation of the first-order α'-corrections of the string effective actions involving the dilaton, metric and two-form fields. Two free parameters interpolate between four-derivative terms that are even and odd with respect to a Z 2-parity transformation that changes the sign of the two-form field. The Z 2-symmetric model reproduces the closed bosonic string, and the heterotic string effective action is obtained through a Z 2-parity-breaking choice of parameters. The theory is an extension of the generalized frame formulation of Double Field Theory, in which the gauge transformations are deformed by a first-order generalized Green-Schwarz transformation. This deformation defines a duality covariant gauge principle that requires and fixes the four-derivative terms. We discuss the O( d, d) structure of the theory and the (non-)covariance of the required field redefinitions.
T-duality constraints on higher derivatives revisited
NASA Astrophysics Data System (ADS)
Hohm, Olaf; Zwiebach, Barton
2016-04-01
We ask to what extent are the higher-derivative corrections of string theory constrained by T-duality. The seminal early work by Meissner tests T-duality by reduction to one dimension using a distinguished choice of field variables in which the bosonic string action takes a Gauss-Bonnet-type form. By analyzing all field redefinitions that may or may not be duality covariant and may or may not be gauge covariant we extend the procedure to test T-duality starting from an action expressed in arbitrary field variables. We illustrate the method by showing that it determines uniquely the first-order α' corrections of the bosonic string, up to terms that vanish in one dimension. We also use the method to glean information about the O({α}^' 2}) corrections in the double field theory with Green-Schwarz deformation.
ERIC Educational Resources Information Center
Gruber, Ryan; Wind, Andrew; Trevidi, Neema
2000-01-01
Presents four articles considering: (1) the media's role in the coverage of politics; (2) the influence of photography particularly in terms of the president; (3) an event where an Iowa student had a chance to work with professionals while covering politics; and (4) considering scholastic reporters covering national candidates as they learn and…
Gravity and duality between coordinates and matter fields
NASA Astrophysics Data System (ADS)
Vancea, I. V.
2000-05-01
We use the duality between the local Cartezian coordinates and the solutions of the Klein-Gordon equation to parametrize locally the spacetime in terms of wave functions and prepotentials. The components of metric, metric connection, curvature as well as the Einstein equation are given in this parametrization. We also discuss the local duality between coordinates and quantum fields and the metric in this later reparametrization.
Geometric aspects of D-branes and T-duality
NASA Astrophysics Data System (ADS)
Becker, Katrin; Bergman, Aaron
2009-11-01
We explore the differential geometry of T-duality and D-branes. Because D-branes and RR-fields are properly described via K-theory, we discuss the (differential) K-theoretic generalization of T-duality and its application to the coupling of D-branes to RR-fields. This leads to a puzzle involving the transformation of the A-roof genera in the coupling.
The duality principle and inversion of Laplace-Stielties transforms
NASA Astrophysics Data System (ADS)
Pavelyev, A. G.
2016-04-01
The fundamental relation between the Laplace transform, the Stielties transform, and the generalized integral equation of refraction is revealed, and a duality principle is formulated for the solution of inverse problems of radio physics. New formulas of the Laplace-transform inversion satisfying the duality principle are obtained. There is no necessity of contour integration in a complex plane for the relations found, which considerably simplifies the reconstruction of originals and makes it possible to control systematic errors in the experimental data.
Duality quantum algorithm efficiently simulates open quantum systems.
Wei, Shi-Jie; Ruan, Dong; Long, Gui-Lu
2016-01-01
Because of inevitable coupling with the environment, nearly all practical quantum systems are open system, where the evolution is not necessarily unitary. In this paper, we propose a duality quantum algorithm for simulating Hamiltonian evolution of an open quantum system. In contrast to unitary evolution in a usual quantum computer, the evolution operator in a duality quantum computer is a linear combination of unitary operators. In this duality quantum algorithm, the time evolution of the open quantum system is realized by using Kraus operators which is naturally implemented in duality quantum computer. This duality quantum algorithm has two distinct advantages compared to existing quantum simulation algorithms with unitary evolution operations. Firstly, the query complexity of the algorithm is O(d(3)) in contrast to O(d(4)) in existing unitary simulation algorithm, where d is the dimension of the open quantum system. Secondly, By using a truncated Taylor series of the evolution operators, this duality quantum algorithm provides an exponential improvement in precision compared with previous unitary simulation algorithm. PMID:27464855
Duality quantum algorithm efficiently simulates open quantum systems
Wei, Shi-Jie; Ruan, Dong; Long, Gui-Lu
2016-01-01
Because of inevitable coupling with the environment, nearly all practical quantum systems are open system, where the evolution is not necessarily unitary. In this paper, we propose a duality quantum algorithm for simulating Hamiltonian evolution of an open quantum system. In contrast to unitary evolution in a usual quantum computer, the evolution operator in a duality quantum computer is a linear combination of unitary operators. In this duality quantum algorithm, the time evolution of the open quantum system is realized by using Kraus operators which is naturally implemented in duality quantum computer. This duality quantum algorithm has two distinct advantages compared to existing quantum simulation algorithms with unitary evolution operations. Firstly, the query complexity of the algorithm is O(d3) in contrast to O(d4) in existing unitary simulation algorithm, where d is the dimension of the open quantum system. Secondly, By using a truncated Taylor series of the evolution operators, this duality quantum algorithm provides an exponential improvement in precision compared with previous unitary simulation algorithm. PMID:27464855
Duality quantum algorithm efficiently simulates open quantum systems
NASA Astrophysics Data System (ADS)
Wei, Shi-Jie; Ruan, Dong; Long, Gui-Lu
2016-07-01
Because of inevitable coupling with the environment, nearly all practical quantum systems are open system, where the evolution is not necessarily unitary. In this paper, we propose a duality quantum algorithm for simulating Hamiltonian evolution of an open quantum system. In contrast to unitary evolution in a usual quantum computer, the evolution operator in a duality quantum computer is a linear combination of unitary operators. In this duality quantum algorithm, the time evolution of the open quantum system is realized by using Kraus operators which is naturally implemented in duality quantum computer. This duality quantum algorithm has two distinct advantages compared to existing quantum simulation algorithms with unitary evolution operations. Firstly, the query complexity of the algorithm is O(d3) in contrast to O(d4) in existing unitary simulation algorithm, where d is the dimension of the open quantum system. Secondly, By using a truncated Taylor series of the evolution operators, this duality quantum algorithm provides an exponential improvement in precision compared with previous unitary simulation algorithm.
Nonsupersymmetric Seiberg duality, orientifold QCD, and noncritical strings
Armoni, Adi; Moraitis, Gregory; Israeel, Dan; Niarchos, Vasilis
2008-05-15
We propose an electric-magnetic duality and conjecture an exact conformal window for a class of nonsupersymmetric U(N{sub c}) gauge theories with fermions in the (anti)symmetric representation of the gauge group and N{sub f} additional scalar and fermion flavors. The duality exchanges N{sub c}{yields}N{sub f}-N{sub c}{+-}4 leaving N{sub f} invariant, and has common features with Seiberg duality in N=1 super QCD (SQCD) with SU or SO/Sp gauge group. At large N the duality holds due to planar equivalence with N=1 SQCD. At finite N we embed these gauge theories in a setup with D-branes and orientifolds in a nonsupersymmetric, but tachyon-free, noncritical type 0B string theory and argue in favor of the duality in terms of boundary and crosscap state monodromies as in analogous supersymmetric situations. One can verify explicitly that the resulting duals have matching global anomalies. Finally, we comment on the moduli space of these gauge theories and discuss other potential nonsupersymmetric examples that could exhibit similar dualities.
Political News and Political Consciousness
ERIC Educational Resources Information Center
Schertges, Claudia
2007-01-01
This article deals with mass media in modern democratic societies, using the example of Israeli news reports in German television (TV) news. Central to this interest are processes of mediating politics: political socialisation and education; that is to say, empowering citizens via TV news to participate in democratic processes. The article…
NASA Astrophysics Data System (ADS)
Paterson, Matthew
2006-11-01
The car, and the range of social and political institutions which sustain its dominance, play an important role in many of the environmental problems faced by contemporary society. But in order to understand the possibilities for moving towards sustainability and 'greening cars', it is first necessary to understand the political forces that have made cars so dominant. This book identifies these forces as a combination of political economy and cultural politics. From the early twentieth century, the car became central to the organization of capitalism and deeply embedded in individual identities, providing people with a source of value and meaning but in a way which was broadly consistent with social imperatives for mobility. Projects for sustainability to reduce the environmental impacts of cars are therefore constrained by these forces but must deal with them in order to shape and achieve their goals. Addresses the increasingly controversial debate on the place of the car in contemporary society and its contribution to environmental problems Questions whether automobility is sustainable and what political, social and economic forces might prevent this Will appeal to scholars and advanced students from a wide range of disciplines including environmental politics, political economy, environmental studies, cultural studies and geography
Desai, P; Caroprese, B; McKellar, H
2014-06-01
Purpose: To illustrate 25% reduction in CyberKnife prostate SBRT treatment times using a water filled rectal balloon. Methods: We perform prostate SBRT using a 3800cGy in 4 fraction regimen prescribed between 51% 59% iso-dose lines to 95% of PTV using a CyberKnife System. The resultant heterogeneous dosimetry is analogous to HDR dosimetry. Our patients are treated in a feet first supine position to decrease treatment couch sag and also to position the prostate anatomy closer to the robot. CT imaging is performed with a Radiadyne Immobiloc rectal balloon filled with 45-50cc water placed firmly inside the patient's rectum. A treatment plan is developed from this CT study using Multiplan. The patient is treated every other day for 4 days using the rectal balloon for each fraction. Gold fiducials previously implanted inside the prostate are used for tracking by the CyberKnife system. Results: Critical structures comprise the usual GU anatomy of bladder, rectum, urethra, femoral-heads along with emphasis on doses to anterior rectal wall and rectal mucosa. The water filled rectal balloon localizes the rectum, which enables the physician to accurately contour both anterior rectal wall, and rectal mucosa. The balloon also has a gas release valve enabling better patient comfort. Rectum localization enables the CyberKnife system to make fewer corrections resulting in fewer treatment interruptions and time lost to re-adjustment for rectal motion, bowel filling and gas creation. Effective treatment times are reduced by 25% to approximately 45 minutes. Adoption of the balloon has required minimal change to our planning strategy and plan evaluation process. Conclusion: Patient follow-up comparisons show no difference in effectiveness of treatment with and without balloons We conclude that rectal balloons enhance patient comfort and decrease effective treatment times.
Testing distance duality with CMB anisotropies
NASA Astrophysics Data System (ADS)
Räsänen, Syksy; Väliviita, Jussi; Kosonen, Ville
2016-04-01
We constrain deviations of the form T propto (1+z)1+epsilon from the standard redshift-temperature relation, corresponding to modifying distance duality as DL = (1+z)2(1+epsilon) DA. We consider a consistent model, in which both the background and perturbation equations are changed. For this purpose, we introduce a species of dark radiation particles to which photon energy density is transferred, and assume epsilon >= 0. The Planck 2015 release high multipole temperature plus low multipole data give the limit epsilon < 4.5 × 10-3 at 95% C.L. The main obstacle to improving this CMB-only result is strong degeneracy between epsilon and the physical matter densities ωb and ωc. A constraint on deuterium abundance improves the limit to epsilon < 1.8 × 10-3. Adding the Planck high-multipole CMB polarisation and BAO data leads to a small improvement; with this maximal dataset we obtain epsilon < 1.3 × 10-3. This dataset constrains the present dark radiation energy density to at most 12% of the total photon plus dark radiation density. Finally, we discuss the degeneracy between dark radiation and the effective number of relativistic species Neff, and consider the impact of dark radiation perturbations and allowing epsilon < 0 on the results.
A Light-Force Duality Principle
NASA Astrophysics Data System (ADS)
Sharafiddinov, Rasulkhozha S.
2015-04-01
The light used in the Michelson interferometer has the electromagnetic structure. Its source must be unified system of the photon and monophoton. The structural particles suffer in it the periodical interconversion, in which an electric force is converted into a magnetic one and vice versa. Furthermore, the electromagnetic light with his own speed can possess either longitudinal or transversal spin polarization owing to which, ether, namely gravity bends its trajectory in the Michelson interferometer. Of course, in such phenomena appears a part of Newton and Coulomb components of each of the electric and magnetic forces. If these situations follow from a unified principle, the light and force correspond to the two forms of the same matter. Such a correspondence principle expresses the light-force duality. Therefore, any of gauge bosons may serve as the source of a kind of light, confirming that we cannot exclude the existence of both strong and weak light beams in nature. They together with an electromagnetic light constitute naturally united light beam which comes forward in the universe either as a flux of gravitons or as a gravitational wave.
GLSM's, gerbes, and Kuznetsov's homological projective duality
NASA Astrophysics Data System (ADS)
Sharpe, Eric
2013-12-01
In this short note we give an overview of recent work on string propagation on stacks and applications to gauged linear sigma models. We begin by outlining noneffective orbifolds (orbifolds in which a subgroup acts trivially) and related phenomena in two-dimensional gauge theories, which realize string propagation on gerbes. We then discuss the 'decomposition conjecture,' equating conformal field theories of strings on gerbes and strings on disjoint unions of spaces. Finally, we apply these ideas to gauged linear sigma models for complete intersections of quadrics, and use the decomposition conjecture to show that the Landau-Ginzburg points of those models have a geometric interpretation in terms of a (sometimes noncommutative resolution of) a branched double cover, realized via nonperturbative effects rather than as the vanishing locus of a superpotential. These examples violate old unproven lore on GLSM's (namely, that geometric phases must be related by birational transformations), and we conclude by observing that in these examples (and conjecturing more generally in GLSM's), the phases are instead related by Kuznetsov's 'homological projective duality.'
Wronskians, dualities and FZZT-Cardy branes
NASA Astrophysics Data System (ADS)
Chan, Chuan-Tsung; Irie, Hirotaka; Niedner, Benjamin; Yeh, Chi-Hsien
2016-09-01
The resolvent operator plays a central role in matrix models. For instance, with utilizing the loop equation, all of the perturbative amplitudes including correlators, the free-energy and those of instanton corrections can be obtained from the spectral curve of the resolvent operator. However, at the level of non-perturbative completion, the resolvent operator is generally not sufficient to recover all the information from the loop equations. Therefore it is necessary to find a sufficient set of operators which provide the missing non-perturbative information. In this paper, we study generalized Wronskians of the Baker-Akhiezer systems as a manifestation of these new degrees of freedom. In particular, we derive their isomonodromy systems and then extend several spectral dualities to these systems. In addition, we discuss how these Wronskian operators are naturally aligned on the Kac table. Since they are consistent with the Seiberg-Shih relation, we propose that these new degrees of freedom can be identified as FZZT-Cardy branes in Liouville theory. This means that FZZT-Cardy branes are the bound states of elemental FZZT branes (i.e. the twisted fermions) rather than the bound states of principal FZZT-brane (i.e. the resolvent operator).
Disentangling the f(R)-duality
Broy, Benedict J.; Pedro, Francisco G.; Westphal, Alexander
2015-03-16
Motivated by UV realisations of Starobinsky-like inflation models, we study generic exponential plateau-like potentials to understand whether an exact f(R)-formulation may still be obtained when the asymptotic shift-symmetry of the potential is broken for larger field values. Potentials which break the shift symmetry with rising exponentials at large field values only allow for corresponding f(R)-descriptions with a leading order term R{sup n} with 1
Testing distance duality with CMB anisotropies
NASA Astrophysics Data System (ADS)
Räsänen, Syksy; Väliviita, Jussi; Kosonen, Ville
2016-04-01
We constrain deviations of the form T propto (1+z)1+epsilon from the standard redshift-temperature relation, corresponding to modifying distance duality as DL = (1+z)2(1+epsilon) DA. We consider a consistent model, in which both the background and perturbation equations are changed. For this purpose, we introduce a species of dark radiation particles to which photon energy density is transferred, and assume epsilon >= 0. The Planck 2015 release high multipole temperature plus low multipole data give the limit epsilon < 4.5 × 10‑3 at 95% C.L. The main obstacle to improving this CMB-only result is strong degeneracy between epsilon and the physical matter densities ωb and ωc. A constraint on deuterium abundance improves the limit to epsilon < 1.8 × 10‑3. Adding the Planck high-multipole CMB polarisation and BAO data leads to a small improvement; with this maximal dataset we obtain epsilon < 1.3 × 10‑3. This dataset constrains the present dark radiation energy density to at most 12% of the total photon plus dark radiation density. Finally, we discuss the degeneracy between dark radiation and the effective number of relativistic species Neff, and consider the impact of dark radiation perturbations and allowing epsilon < 0 on the results.
Topological T-duality, automorphisms and classifying spaces
NASA Astrophysics Data System (ADS)
Pande, Ashwin S.
2014-08-01
We extend the formalism of Topological T-duality to spaces which are the total space of a principal S1-bundle p:E→W with an H-flux in H3(E,Z) together with an automorphism of the continuous-trace algebra on E determined by H. The automorphism is a ‘topological approximation’ to a gerby gauge transformation of spacetime. We motivate this physically from Buscher’s Rules for T-duality. Using the Equivariant Brauer Group, we connect this problem to the C∗-algebraic formalism of Topological T-duality of Mathai and Rosenberg (2005). We show that the study of this problem leads to the study of a purely topological problem, namely, Topological T-duality of triples (p,b,H) consisting of isomorphism classes of a principal circle bundle p:X→B and classes b∈H2(X,Z) and H∈H3(X,Z). We construct a classifying space R for triples in a manner similar to the work of Bunke and Schick (2005). We characterize R up to homotopy and study some of its properties. We show that it possesses a natural self-map which induces T-duality for triples. We study some properties of this map.
How Internal Political Efficacy Translates Political Knowledge Into Political Participation
Reichert, Frank
2016-01-01
This study presents evidence for the mediation effect of political knowledge through political self-efficacy (i.e. internal political efficacy) in the prediction of political participation. It employs an action theoretic approach—by and large grounded on the Theory of Planned Behaviour—and uses data from the German Longitudinal Election Study to examine whether political knowledge has distinct direct effects on voting, conventional, and/or unconventional political participation. It argues that political knowledge raises internal political efficacy and thereby indirectly increases the chance that a citizen will participate in politics. The results of mediated multiple regression analyses yield evidence that political knowledge indeed translates into internal political efficacy, thus it affects political participation of various kinds indirectly. However, internal political efficacy and intentions to participate politically yield simultaneous direct effects only on conventional political participation. Sequentially mediated effects appear for voting and conventional political participation, with political knowledge being mediated by internal political efficacy and subsequently also by behavioural intentions. The mediation patterns for unconventional political participation are less clear though. The discussion accounts for restrictions of this study and points to questions for answer by future research. PMID:27298633
NASA Astrophysics Data System (ADS)
Metlitski, Max; Vishwanath, Ashvin
Particle-vortex duality is a powerful theoretical tool that has been used to study systems of bosons. In arXiv:1505.05142, we propose an analogous duality for Dirac fermions in 2+1 dimensions. The physics of a single Dirac cone is proposed to be described by a dual theory, QED3 with a dual Dirac fermion coupled to a u(1) gauge field. This duality is established by considering two alternate descriptions of the 3d topological insulator (TI) surface. The first description is the usual Dirac cone surface state. The second description is accessed via an electric-magnetic duality of the bulk TI coupled to a gauge field, which maps it to a gauged topological superconductor. This alternate description ultimately leads to a new surface theory - dual QED3. The dual theory provides an explicit derivation of the T-Pfaffian state, a proposed surface topological order of the TI, which is simply the paired superfluid state of the dual fermions. The roles of time reversal and particle-hole symmetry are exchanged by the duality, which connects some of our results to a recent conjecture by Son on particle-hole symmetric quantum Hall states at ν = 1 / 2 .
Unification of type-II strings and T duality.
Hohm, Olaf; Kwak, Seung Ki; Zwiebach, Barton
2011-10-21
We present a unified description of the low-energy limits of type-II string theories. This is achieved by a formulation that doubles the space-time coordinates in order to realize the T-duality group O(10,10) geometrically. The Ramond-Ramond fields are described by a spinor of O(10,10), which couples to the gravitational fields via the Spin(10,10) representative of the so-called generalized metric. This theory, which is supplemented by a T-duality covariant self-duality constraint, unifies the type-II theories in that each of them is obtained for a particular subspace of the doubled space. PMID:22107505
Kramers-Wannier duality applied to the boolean satifiability problem
NASA Astrophysics Data System (ADS)
Mitchell, Joe; Hsu, Benjamin; Galitski, Victor
2014-03-01
Kramers-Wannier duality, first considered in 1941, is an exact technique used in statistical mechanics to relate two models together through an order-disorder transformation, and thereby study their structure and critical phenomena. The boolean satisfiability problem is one of the most important problems in computer science, specifically complexity theory; it is the first proven NP-complete problem. Using a mapping to a multi-spin Ising model in the limit of zero temperature, we present an application of Kramers-Wannier duality to this problem. This results in a novel relationship between solving the boolean satisfiability counting problem and a different computational problem: listing the non-negative solutions to a particular system of linear integer equations. This mapping relates the complexity of the two problems. We discuss the generality of Kramers-Wannier duality and its possible application to other computational problems. This research was supported by NSF-CAREER award No. DMR-0847224 and Simons Foundation.
Fair sampling perspective on an apparent violation of duality.
Bolduc, Eliot; Leach, Jonathan; Miatto, Filippo M; Leuchs, Gerd; Boyd, Robert W
2014-08-26
In the event in which a quantum mechanical particle can pass from an initial state to a final state along two possible paths, the duality principle states that "the simultaneous observation of wave and particle behavior is prohibited" [Scully MO, Englert B-G, Walther H (1991) Nature 351:111-116]. Whereas wave behavior is associated with the observation of interference fringes, particle behavior generally corresponds to the acquisition of which-path information by means of coupling the paths to a measuring device or part of their environment. In this paper, we show how the consequences of duality change when allowing for biased sampling, that is, postselected measurements on specific degrees of freedom of the environment of the two-path state. Our work gives insight into a possible mechanism for obtaining simultaneous high which-path information and high-visibility fringes in a single experiment. Further, our results introduce previously unidentified avenues for experimental tests of duality. PMID:25114237
New localization mechanism and Hodge duality for q -form field
NASA Astrophysics Data System (ADS)
Fu, Chun-E.; Liu, Yu-Xiao; Guo, Heng; Zhang, Sheng-Li
2016-03-01
In this paper, we investigate the problem of localization and the Hodge duality for a q -form field on a p -brane with codimension one. By a general Kaluza-Klein (KK) decomposition without gauge fixing, we obtain two Schrödinger-like equations for two types of KK modes of the bulk q -form field, which determine the localization and mass spectra of these KK modes. It is found that there are two types of zero modes (the 0-level modes): a q -form zero mode and a (q -1 )-form one, which cannot be localized on the brane at the same time. For the n -level KK modes, there are two interacting KK modes, a massive q -form KK mode and a massless (q -1 )-form one. By analyzing gauge invariance of the effective action and choosing a gauge condition, the n -level massive q -form KK mode decouples from the n -level massless (q -1 )-form one. It is also found that the Hodge duality in the bulk naturally becomes two dualities on the brane. The first one is the Hodge duality between a q -form zero mode and a (p -q -1 )-form one, or between a (q -1 )-form zero mode and a (p -q )-form one. The second duality is between two group KK modes: one is an n -level massive q -form KK mode with mass mn and an n -level massless (q -1 )-form mode; another is an n -level (p -q )-form one with the same mass mn and an n -level massless (p -q -1 )-form mode. Because of the dualities, the effective field theories on the brane for the KK modes of the two dual bulk form fields are physically equivalent.
Lorentz covariance, higher-spin superspaces and self-duality
Devchand, Chandrashekar; Nuyts, Jean
1998-12-15
Lorentz covariant generalisations of the notions of supersymmetry, superspace and self-duality are discussed. The essential idea is to extend standard constructions by allowing tangent vectors and coordinates which transform according to more general Lorentz representations than solely the spinorial and vectorial ones of standard lore. Such superspaces provide model configuration spaces for theories of arbitrary spin fields. Our framework is an elegant one for handling higher-dimensional theories in a manifestly SO(3,1) cavariant fashion. A further application is the construction of a hierarchy of solvable Lorentz covariant systems generalising four-dimensional self-duality.
Thermal duality and Hagedorn transition from p-adic strings.
Biswas, Tirthabir; Cembranos, Jose A R; Kapusta, Joseph I
2010-01-15
We develop the finite temperature theory of p-adic string models. We find that the thermal properties of these nonlocal field theories can be interpreted either as contributions of standard thermal modes with energies proportional to the temperature, or inverse thermal modes with energies proportional to the inverse of the temperature, leading to a thermal duality at leading order (genus one) analogous to the well-known T duality of string theory. The p-adic strings also recover the asymptotic limits (high and low temperature) for arbitrary genus that purely stringy calculations have yielded. We also discuss our findings surrounding the nature of the Hagedorn transition. PMID:20366584
Thermodynamics of quasiconformal theories from gauge/gravity duality
Alanen, Janne; Kajantie, Keijo; Tuominen, Kimmo
2010-09-01
We use gauge/gravity duality to study the thermodynamics of a generic almost conformal theory, specified by its beta function. Three different phases are identified, a high temperature phase of massless partons, an intermediate quasiconformal phase and a low temperature confining phase. The limit of a theory with infrared fixed point, in which the coupling does not run to infinity, is also studied. The transitions between the phases are of first order or continuous, depending on the parameters of the beta function. The results presented follow from gauge/gravity duality; no specific boundary theory is assumed, only its beta function.
Thermal Duality and Hagedorn Transition from p-adic Strings
Biswas, Tirthabir; Cembranos, Jose A. R.; Kapusta, Joseph I.
2010-01-15
We develop the finite temperature theory of p-adic string models. We find that the thermal properties of these nonlocal field theories can be interpreted either as contributions of standard thermal modes with energies proportional to the temperature, or inverse thermal modes with energies proportional to the inverse of the temperature, leading to a thermal duality at leading order (genus one) analogous to the well-known T duality of string theory. The p-adic strings also recover the asymptotic limits (high and low temperature) for arbitrary genus that purely stringy calculations have yielded. We also discuss our findings surrounding the nature of the Hagedorn transition.
Entanglement entropy and duality in AdS4
NASA Astrophysics Data System (ADS)
Bakas, Ioannis; Pastras, Georgios
2015-07-01
Small variations of the entanglement entropy δS and the expectation value of the modular Hamiltonian δE are computed holographically for circular entangling curves in the boundary of AdS4, using gravitational perturbations with general boundary conditions in spherical coordinates. Agreement with the first law of thermodynamics, δS = δE, requires that the line element of the entangling curve remains constant. In this context, we also find a manifestation of electric-magnetic duality for the entanglement entropy and the corresponding modular Hamiltonian, following from the holographic energy-momentum/Cotton tensor duality.
Low-Q scaling, duality, and the EMC effect
J. Arrington; R. Ent; C. E. Keppel; J. Mammei; I. Niculescu
2003-07-01
High energy lepton scattering has been the primary tool for mapping out the quark distributions of nucleons and nuclei. Data on the proton and deuteron have shown that there is a fundamental connection between the low and high energy regimes, referred to as quark-hadron duality. We present the results of similar studies to more carefully examine scaling, duality, and in particular the EMC effect in nuclei. We extract nuclear modifications to the structure function in the resonance region, and for the first time demonstrate that nuclear effects in the resonance region are identical to those measured in deep inelastic scattering.
Dixit, Avinash K.; Weibull, Jörgen W.
2007-01-01
Failures of government policies often provoke opposite reactions from citizens; some call for a reversal of the policy, whereas others favor its continuation in stronger form. We offer an explanation of such polarization, based on a natural bimodality of preferences in political and economic contexts and consistent with Bayesian rationality. PMID:17452633
NASA Technical Reports Server (NTRS)
Lucas, W. R.
1972-01-01
Certain decisions, problems, and successes are selected to recall the great impact of the 1950s on the history of rocketry, and particularly the inauguration of the space age. In reviewing the history of the Redstone, Juno, and Jupiter, some of the largest stepping stones to space, problems stand out in three areas: technical or engineering, management, and political.
ERIC Educational Resources Information Center
Brown, William R.
The internal politics of colleges and the influence of a current emphasis on efficiency on the traditional independence of the academician are analyzed. It is suggested that the academician does not work in the same differentiated, and therefore interdependent, way as someone in industry or a bureaucracy. Academic activity is segmented, which…
ERIC Educational Resources Information Center
Maslow, Abraham
1977-01-01
This article expresses some last thoughts from Abraham Maslow on his vision of humanistic psychology. He suggests that the two main problems of creating the good person and the good society are interwoven inextricably. He gives some social and political mechanisms which would enhance desirable personal growth and considers the main tasks of…
Duality of female employment in Pakistan.
Kazi, S; Raza, B
1991-01-01
The trends in the level and pattern of women's employment in Pakistan in terms of supply and demand factors which influence women's participation in the labor market are discussed. Women's labor participation is underestimated in official sources such as the Labor Force Survey (LFS) and the Population Census. Figures which were obtained from micro level surveys and the Agricultural Census, show the duality of employment at the top and bottom socioeconomically. LFS data show the female share of the professional work force to have risen from 15.5% to 18.3% between 1984-95 and 1987-88, which translates to 33% of teachers and 25% of physicians being women. Urban female participation rates have increased only slightly from 3 to 5% between 1971 and 72 and 1987-88, based on LFS data, while informal sector surveys have shown an increase of workers who are women who have never worked before in the formal sector. In manufacturing, the female work force remains low at 5% in factories in the Punjab and Sindh, but only 20% were in regular employment compared with 50% of men. Agricultural work on the family farm has increased from 35% in 1972 and 42% in 1980. Increases are also shown in more recent LF surveys. Constraints on both male and female employment are the recent (1978-79 and 1986-87) shift to capital investment in agriculture with tubewells and tractors and in manufacturing. Women's movement into agriculture may be precipitated by men's out migration to urban areas or the Gulf region into other nonfarm occupations. In manufacturing there is exploitation of workers through low overhead costs of temporary or part time help. Supply constraints for women involve cultural restrictions, household responsibilities, and low levels of education and skills. Women enter the work force out of financial need. Data on female-headed households are scarce, but a Karachi survey finds that most female-headed households belong to the poorest strata and women work when family size
Asquith, G.B. )
1990-06-01
Reservoirs with microporosity present significant exploration opportunities as well as new exploitation potential. In sandstones with clay or shale, clay microporosity may distort a number of log-calculated parameters that form the basis for estimating producible reserves. Since reservoirs with microporosity often appear water-productive, the author concludes that producible hydrocarbons in such zones often may be overlooked. Standard formation evaluation approaches that correct for the presence of shale or clay are hampered by the lack of accurate methods for determining volume of clay (Vcl), total shale porosity ({phi}tsh), bound water resistivity (Rb), and resistivity of dispersed clay (Rcl) or by the lack of laboratory-determined values for cation exchange capacity (CEC). In addition some shaly sand corrections (Fertl and Dispersed Clay) can be unreliable in shaly sands with large formation water resistivities (Rw). This paper proposes a microporosity approach which does not require values for Vcl, {phi}tsh, Rcl, Rb, or CEC, and is based on the observation that CEC is related to specific surface area of clays, and specific surface area is related to the amount of clay-bound water-filled microporosity. Without the limitations imposed on other approaches the microporosity method has broad application.
NASA Astrophysics Data System (ADS)
Berzak Hopkins, Laura
2013-03-01
Politics and policy affect all of us, both as scientists and as citizens, and issues ranging from laboratory budgets to arms control treaties clearly require research problem-solving skills and technical expertise. There is a critical role for scientists in each aspect of the political system, and in fact, we as a society need more scientists to take part in politics. Furthermore, the research we pursue has important societal applications and is fascinating! We have a right and a responsibility to share our scientific knowledge not only with each other, but with the general public as well. So, why are we as a community of scientists reticent in the public arena, hesitant to enter politics, and even at times unsupportive of our peers who transition into governmental roles? In this time of fiscal constraint, when difficult research funding (and de-funding) choices are regularly being made, we as scientists must step up to the plate, reach across the aisle, and explain why what we do is fascinating, inspiring, and important, not just to us, but to society as a whole. A range of policy-relevant roles exists inside and outside the laboratory, such as Congressional Fellowships. Each year the Congressional Fellowships program brings together approximately thirty scientists at all stages of their careers to serve as scientific advisors in a variety of offices in the U.S. Senate and House of Representatives. Although the jump from lab to lobbying meetings can be frustrating, the transition can also be intriguing. Firsthand experience with the ``how'' and ``why'' (or lack thereof) of politics and policy is invaluable and provides a unique opportunity to expand and broaden one's background. The opportunity to work on Capitol Hill is unparalleled, particularly because our nation has a definite need for scientists with the inclination and interest to inform and develop policy. But, whatever role you decide to take, from contributing scientific news to local publications to
Nonlinear electromagnetic self-duality and Legendre transformations
Gaillard, M.K.; Zumino, B.
1997-12-09
We discuss continuous duality transformations and the properties of classical theories with invariant interactions between electromagnetic fields and matter. The case of scalar fields is treated in some detail. Special discrete elements of the continuous group are shown to be related to the Legendre transformation with respect to the field strengths.
Leadership of International Schools: Understanding and Managing Dualities
ERIC Educational Resources Information Center
Keller, Dan
2015-01-01
Leaders of international schools find themselves operating within a loosely defined, yet rapidly growing, specialty niche of education. The leadership context for these schools is often filled with ambiguity and complex tensions between opposing forces. This article proposes a two-stage framework for critically analyzing the dualities of…
Quaternionic Torsion Geometry, Superconformal Symmetry and T-duality
Swann, Andrew
2009-02-02
HyperKaehler metrics with torsion (HKT metrics) are constructed via superconformal symmetry. It is shown how T-duality interpreted as a twist construction for circle actions provides a number of compact simply-connected examples. Further applications of the twist construction are discussed to obtain compact simply-connected HKT manifolds with few symmetries and to construct all HKT nilmanifolds.
Duality in entanglement of macroscopic states of light
NASA Astrophysics Data System (ADS)
Lee, Su-Yong; Lee, Chang-Woo; Kurzyński, Paweł; Kaszlikowski, Dagomir; Kim, Jaewan
2016-08-01
We investigate duality in entanglement of a bipartite multiphoton system generated from a coherent state of light. The system can exhibit polarization entanglement if the two parts are distinguished by their parity, or parity entanglement if the parts are distinguished by polarization. It was shown in Phys. Rev. Lett. 110, 140404 (2013), 10.1103/PhysRevLett.110.140404 that this phenomenon can be exploited as a method to test indistinguishability of two particles and it was conjectured that one can also test indistinguishability of macroscopic systems. We propose a setup to test this conjecture. Contrary to the previous studies using two-particle interference effect as in the Hong-Ou- Mandel setup, our setup neither assumes that the tested state is composed of single particles nor requires that the total number of particles be fixed. Consequently, the notion of entanglement duality is shown to be compatible with a broader class of physical systems. Moreover, by observing duality in entanglement in the above system one can confirm that macroscopic systems exhibit quantum behavior. As a practical side, entanglement duality is a useful concept that enables adaptive conversion of entanglement of one degree of freedom (DOF) to that of another DOF according to varying quantum protocols.
Langlands Duality in LIOUVILLE-H3+ Wznw Correspondence
NASA Astrophysics Data System (ADS)
Giribet, Gaston; Nakayama, Yu; Nicolás, Lorena
We show a physical realization of the Langlands duality in correlation functions of H3+ WZNW model. We derive a dual version of the Stoyanovky-Riabult-Teschner (SRT) formula that relates the correlation function of the H3+ WZNW and the dual Liouville theory to investigate the level duality k - 2 → (k - 2)-1 in the WZNW correlation functions. Then, we show that such a dual version of the H3+-Liouville relation can be interpreted as a particular case of a biparametric family of nonrational conformal field theories (CFT's) based on the Liouville correlation functions, which was recently proposed by Ribault. We study symmetries of these new nonrational CFT's and compute correlation functions explicitly by using the free field realization to see how a generalized Langlands duality manifests itself in this framework. Finally, we suggest an interpretation of the SRT formula as realizing the Drinfeld-Sokolov Hamiltonian reduction. Again, the Hamiltonian reduction reveals the Langlands duality in the H3+ WZNW model. Our new identity for the correlation functions of H3+ WZNW model may yield a first step to understand quantum geometric Langlands correspondence yet to be formulated mathematically.
Gaugino condensation, loop corrections and S-duality constraint
Saririan, K.
1996-11-01
This talk is a brief review of gaugino condensation in superstring effective field theories and some related issues (such as renormalization of the gauge coupling in the effective supergravity theories and modular anomaly cancellation). As a specific example, we discuss a model containing perturbative (1-loop) corrections to the K{umlt a}hler potential and approximate S-duality symmetry.
NASA Astrophysics Data System (ADS)
Głazek, Stanisław D.; Trawiński, Arkadiusz P.
2013-11-01
It is observed and illustrated in a greatly simplified example that the idea of AdS/QFT duality can be considered a special case of the Ehrenfest’s correspondence principle between classical and quantum mechanics in the context of relativistic dynamics of fields and renormalization group procedure for effective particles.
Ptatscheck, Christoph; Traunspurger, Walter
2015-01-01
Objectives In this study we investigated the dynamics of meiofaunal and macrofaunal communities in artificial water-filled tree holes. The abundances and, for the first time, biomasses and secondary production rates of these communities were examined. The experimental set-up consisted of 300 brown plastic cups placed in temperate mixed forests and sampled five times over a period of 16 months to determine the impact of (i) seasonal events, (ii) physicochemical parameters, and (iii) food resources on the tree hole metazoans. Outcomes Metazoan organisms, especially the meiofauna (rotifers and nematodes) occupied nearly all of the cups (> 99%) throughout the year. Between 55% and 99% of the metazoan community was represented by rotifers (max. 557,000 individuals 100 cm-2) and nematodes (max. 58,000 individuals 100 cm-2). Diptera taxa, particularly Dasyhelea sp. (max. 256 individuals 100 cm-2) dominated the macrofaunal community. Macrofauna accounted for the majority of the metazoan biomass, with a mean dry weight of 5,800 μg 100 cm-2 and an annual production rate of 20,400 μg C 100 cm-2, whereas for meiofauna mean biomass and annual production were 100 μg 100 cm-2 and 5,300 μg C 100 cm-2, respectively. The macrofaunal taxa tended to show more fluctuating population dynamic while the meiofaunal dynamic was rather low with partly asynchronous development. Seasonality (average temperature and rain intervals) had a significant impact on both meiofauna and macrofauna. Furthermore, bottom-up control (chlorophyll-a and organic carbon), mainly attributable to algae, was a significant factor that shaped the metazoan communities. In contrast, physicochemical water parameters had no evident influence. 23.7% of organism density distribution was explained by redundancy analysis (RDA) indicating a high dynamic and asynchrony of the systems. PMID:26284811
Higher nonunital Quillen K‧-theory, KK-dualities and applications to topological T-dualities
NASA Astrophysics Data System (ADS)
Mahanta, Snigdhayan
2011-05-01
Quillen introduced a new K0'-theory of nonunital rings in Quillen (1996) [1] and showed that, under some assumptions (weaker than the existence of unity), this new theory agrees with the usual algebraic K0alg-theory. For a field k of characteristic 0, we introduce higher nonunital K-theory of k-algebras, denoted as KQ, which extends Quillen's original definition of the K0' functor. We show that the KQ-theory is Morita invariant and satisfies excision connectively, in a suitable sense, on the category of idempotent k-algebras. Using these two properties we show that the KQ-theory agrees with the topological K-theory of stable C∗-algebras. The machinery enables us to produce a DG categorical formalism of topological homological T-duality using bivariant K-theory classes. A connection with strong deformations of C∗-algebras and some other potential applications to topological field theories are discussed towards the end.
Overcoming obstacles to colour-kinematics duality at two loops
NASA Astrophysics Data System (ADS)
Mogull, Gustav; O'Connell, Donal
2015-12-01
The discovery of colour-kinematics duality has allowed great progress in our understanding of the UV structure of gravity. However, it has proven difficult to find numerators which satisfy colour-kinematics duality in certain cases. We discuss obstacles to building a set of such numerators in the context of the five-gluon amplitude with all helicities positive at two loops. We are able to overcome the obstacles by adding more loop momentum to our numerator to accommodate tension between the values of certain cuts and the symmetries of certain diagrams. At the same time, we maintain control over the size of our ansatz by identifying a highly constraining but desirable symmetry property of our master numerator. The resulting numerators have twelve powers of loop momenta rather than the seven one would expect from the Feynman rules.
Pure gravities via color-kinematics duality for fundamental matter
NASA Astrophysics Data System (ADS)
Johansson, Henrik; Ochirov, Alexander
2015-11-01
We give a prescription for the computation of loop-level scattering amplitudes in pure Einstein gravity, and four-dimensional pure supergravities, using the color-kinematics duality. Amplitudes are constructed using double copies of pure (super-)Yang-Mills parts and additional contributions from double copies of fundamental matter, which are treated as ghosts. The opposite-statistics states cancel the unwanted dilaton and axion in the bosonic theory, as well as the extra matter supermultiplets in the supergravity theories. As a spinoff, we obtain a prescription for obtaining amplitudes in supergravities with arbitrary non-self-interacting matter. As a prerequisite, we extend the color-kinematics duality from the adjoint to the fundamental representation of the gauge group. We explain the numerator relations that the fundamental kinematic Lie algebra should satisfy. We give nontrivial evidence supporting our construction using explicit tree and loop amplitudes, as well as more general arguments.
Vortex operator and BKT transition in Abelian duality
NASA Astrophysics Data System (ADS)
Chern, Tong
2016-04-01
We give a new simple derivation for the sine-Gordon description of Berezinskii-Kosterlitz-Thouless (BKT) phase transition. Our derivation is simpler than traditional derivations. Besides, our derivation is a continuous field theoretic derivation by using path integration, different from the traditional derivations which are based on lattice theory or based on Coulomb gas model. Our new derivation relies on Abelian duality of two dimensional quantum field theory. By utilizing this duality in path integration, we find that the vortex configurations are naturally mapped to exponential operators in dual description. Since these operators are the vortex operators that can create vortices, the sine-Gordon description then naturally follows. Our method may be useful for the investigation to the BKT physics of superconductors.
Quark-Hadron Duality in Neutron (3He) Spin Structure
Solvignon, Patricia; Liyanage, Nilanga; Chen, Jian-Ping; Choi, Seonho; Aniol, Konrad; Averett, Todd; Boeglin, Werner; Camsonne, Alexandre; Cates, Gordon; Chang, C.; Chang, C.C.; Chang, C.; Chang, C.C.; Chudakov, Eugene; Craver, Brandon; Cusanno, Francesco; Deur, Alexandre; Dutta, Dipangkar; Ent, Rolf; Feuerbach, Robert; Frullani, Salvatore; Gao, Haiyan; Garibaldi, Franco; Gilman, Ronald; Glashausser, Charles; Gorbenko, Viktor; Hansen, Jens-Ole; Higinbotham, Douglas; Ibrahim, Hassan; Jiang, Xiaodong; Jones, Mark; Kelleher, Aidan; Kelly, J.; Keppel, Cynthia; Kim, Wooyoung; Korsch, Wolfgang; Kramer, Kevin; Kumbartzki, Gerfried; LeRose, John; Lindgren, Richard; Ma, Bin; Margaziotis, Demetrius; Markowitz, Pete; McCormick, Kathy; Meziani, Zein-Eddine; Michaels, Robert; Moffit, Bryan; Monaghan, Peter; Munoz-Camacho, Carlos; Paschke, Kent; Reitz, Bodo; Saha, Arunava; Sheyor, Ran; Singh, Jaideep; Slifer, Karl; Sulkosky, Vince; Sulkosky, Vincent; Sulkosky, Vince; Sulkosky, Vincent; Tobias, William; Urciuoli, Guido; Wang, Kebin; Wijesooriya, Krishni; Wojtsekhowski, Bogdan; Woo, Seungtae; Yang, Jae-Choon; Zheng, Xiaochao; Zhu, Lingyan
2008-10-01
We present experimental results of the first high-precision test of quark-hadron duality in the spin-structure function g_1 of the neutron and $^3$He using a polarized 3He target in the four-momentum-transfer-squared range from 0.7 to 4.0 (GeV/c)^2. Global duality is observed for the spin-structure function g_1 down to at least Q^2 = 1.8 (GeV/c)^2 in both targets. We have also formed the photon-nucleon asymmetry A_1 in the resonance region for 3He and found no strong Q^2-dependence above 2.2 (GeV/c)^2.
Critical interfaces and duality in the Ashkin-Teller model
Picco, Marco; Santachiara, Raoul
2011-06-15
We report on the numerical measures on different spin interfaces and Fortuin-Kasteleyn (FK) cluster boundaries in the Askhin-Teller (AT) model. For a general point on the AT critical line, we find that the fractal dimension of a generic spin cluster interface can take one of four different possible values. In particular we found spin interfaces whose fractal dimension is d{sub f}=3/2 all along the critical line. Furthermore, the fractal dimension of the boundaries of FK clusters was found to satisfy all along the AT critical line a duality relation with the fractal dimension of their outer boundaries. This result provides clear numerical evidence that such duality, which is well known in the case of the O(n) model, exists in an extended conformal field theory.
Some aspects of self-duality and generalised BPS theories
NASA Astrophysics Data System (ADS)
Adam, C.; Ferreira, L. A.; da Hora, E.; Wereszczynski, A.; Zakrzewski, W. J.
2013-08-01
If a scalar field theory in (1+1) dimensions possesses soliton solutions obeying first order BPS equations, then, in general, it is possible to find an infinite number of related field theories with BPS solitons which obey closely related BPS equations. We point out that this fact may be understood as a simple consequence of an appropriately generalised notion of self-duality. We show that this self-duality framework enables us to generalize to higher dimensions the construction of new solitons from already known solutions. By performing simple field transformations our procedure allows us to relate solitons with different topological properties. We present several interesting examples of such solitons in two and three dimensions.
Electric-magnetic duality and the conditions of inflationary magnetogenesis
Giovannini, Massimo
2010-04-01
The magnetogenesis scenarios triggered by the early variation of the gauge coupling are critically analyzed. In the absence of sources, it is shown that the electric power spectra can be explicitly computed from the magnetic power spectra by means of electric-magnetic duality transformations. In the absence of sources the reverse is also true. The remnants of a pre-inflationary expansion and the reheating process break explicitly electric-magnetic duality by inducing Ohmic currents. The generation of large-scale magnetic field and the physical distinction between electric and magnetic observables stems, in this class of models, from the final value reached by the conductivity of the plasma right after inflation. Specific numerical examples are given. The physical requirements of viable magnetogenesis scenarios are spelled out.
Ultrafast Optical Signal Processing Based Upon Space-Time Dualities
NASA Astrophysics Data System (ADS)
van Howe, James; Xu, Chris
2006-07-01
The last two decades have seen a wealth of optical instrumentation based upon the concepts of space-time duality. A historical overview of how this beautiful framework has been exploited to develop instruments for optical signal processing is presented. The power of this framework is then demonstrated by reviewing four devices in detail based upon space-time dualities that have been experimentally demonstrated: 1) a time-lens timing-jitter compensator for ultralong-haul dense-wavelength-division-multiplexed dispersion-managed soliton transmission, 2) a multiwavelength pulse generator using time-lens compression, 3) a programmable ultrafast optical delay line by use of a time-prism pair, and 4) an enhanced ultrafast optical delay line by use of soliton propagation between a time-prism pair.
Topological T-duality for torus bundles with monodromy
NASA Astrophysics Data System (ADS)
Baraglia, David
2015-05-01
We give a simplified definition of topological T-duality that applies to arbitrary torus bundles. The new definition does not involve Chern classes or spectral sequences, only gerbes and morphisms between them. All the familiar topological conditions for T-duals are shown to follow. We determine necessary and sufficient conditions for existence of a T-dual in the case of affine torus bundles. This is general enough to include all principal torus bundles as well as torus bundles with arbitrary monodromy representations. We show that isomorphisms in twisted cohomology, twisted K-theory and of Courant algebroids persist in this general setting. We also give an example where twisted K-theory groups can be computed by iterating T-duality.
Generalized entropies and logarithms and their duality relations
Hanel, Rudolf; Thurner, Stefan; Gell-Mann, Murray
2012-01-01
For statistical systems that violate one of the four Shannon–Khinchin axioms, entropy takes a more general form than the Boltzmann–Gibbs entropy. The framework of superstatistics allows one to formulate a maximum entropy principle with these generalized entropies, making them useful for understanding distribution functions of non-Markovian or nonergodic complex systems. For such systems where the composability axiom is violated there exist only two ways to implement the maximum entropy principle, one using escort probabilities, the other not. The two ways are connected through a duality. Here we show that this duality fixes a unique escort probability, which allows us to derive a complete theory of the generalized logarithms that naturally arise from the violation of this axiom. We then show how the functional forms of these generalized logarithms are related to the asymptotic scaling behavior of the entropy. PMID:23129618
Political Reactance and Political Reality: A Theory of Political Alienation.
ERIC Educational Resources Information Center
Long, Samuel
The research investigated political and psychological reactance among adolescents. Political reactance is interpreted to include feelings of political alienation and distrust. Psychological reactance is defined as behavior by an individual in response to reduction or threatened reduction of freedom. A model was created which expanded existing…
A Derivation of the Etherington's Distance-Duality Equation
NASA Astrophysics Data System (ADS)
Heymann, Yuri
2015-07-01
The Etherington's distance-duality equation is the relationship between the luminosity distance of standard candles and the angular-diameter distance. This relationship has been validated from astronomical observations based on the X-ray surface brightness and the Sunyaev-Zel'dovich effect of galaxy clusters. In the present study, we propose a derivation of the Etherington's reciprocity relation in the dichotomous cosmology.
Alday-Maldacena Duality and AdS Plateau Problem
NASA Astrophysics Data System (ADS)
Morozov, A.
A short summary of approximate approach to the study of minimal surfaces in AdS, based on solving Nambu-Goto equations iteratively. Today, after partial denunciation of the BDS conjecture, this looks like the only constructive approach to understanding the ways of its possible modification and thus to saving the Alday-Maldacena duality. Numerous open technical problems are explicitly formulated throughout the text.
The Onset of Quark-Hadron Duality in Pion Electroproduction
Tigran Navasardyan; Gary Adams; Abdellah Ahmidouch; Tatiana Angelescu; John Arrington; Razmik Asaturyan; O. Baker; Nawal Benmouna; Crystal Bertoncini; Henk Blok; Werner Boeglin; Peter Bosted; Herbert Breuer; Michael Christy; Simon Connell; Yonggang Cui; Mark Dalton; Samuel Danagoulian; Donal Day; T. Dodario; James Dunne; Dipangkar Dutta; Najib Elkhayari; Rolf Ent; Howard Fenker; Valera Frolov; Liping Gan; David Gaskell; Kawtar Hafidi; Wendy Hinton; Roy Holt; Tanja Horn; Garth Huber; Ed Hungerford; Xiaodong Jiang; Mark Jones; Kyungseon Joo; Narbe Kalantarians; James Kelly; Cynthia Keppel; Edward Kinney; V. Kubarovski; Ya Li; Yongguang Liang; Simona Malace; Pete Markowitz; Erin McGrath; Daniella Mckee; David Meekins; Hamlet Mkrtchyan; Brian Moziak; Gabriel Niculescu; Maria-Ioana Niculescu; Allena Opper; Tanya Ostapenko; Paul Reimer; Joerg Reinhold; Julie Roche; Stephen Rock; Elaine Schulte; Edwin Segbefia; C. Smith; G.R. Smith; Paul Stoler; Vardan Tadevosyan; Liguang Tang; Maurizio Ungaro; Alicia Uzzle; Sandra Vidakovic; Anthony Villano; William Vulcan; Miao Wang; Glen Warren; Frank Wesselmann; Bogdan Wojtsekhowski; Stephen Wood; Chuncheng Xu; Lulin Yuan; Xiaochao Zheng; Hong Guo Zhu
2006-08-29
A large data set of charged-pion electroproduction from both hydrogen and deuterium targets has been obtained spanning the low-energy residual-mass region. These data conclusively show the onset of the quark-hadron duality phenomenon, as predicted for high-energy hadron electroproduction. We construct several ratios from these data to exhibit the relation of this phenomenon to the high-energy factorization ansatz of electron-quark scattering and subsequent quark-to- pion production mechanisms.
Rowlands' Duality Principle: A Generalization of Noether's Theorem?
NASA Astrophysics Data System (ADS)
Karam, Sabah E.
This paper will examine a physical principle that has been used in making valid predictions and generalizes established conservation laws. In a previous paper it was shown how Rowlands' zero-totality condition could be viewed as a generalization of Newton's third law of motion. In this paper it will be argued that Rowlands' Duality Principle is a generalization of Noether's Theorem and that the two principles taken together are truly foundational principles that have tamed Metaphysics.
Complementary variational principle and duality in mathematical programming.
NASA Technical Reports Server (NTRS)
Chan, W. L.; Leininger, G. G.; Farison, J. B.
1973-01-01
The relationship between the complementary variational principle and duality in mathematical programming is demonstrated through a geometric approach in a Hilbert space setting. A necessary and sufficient condition for the existence of such a principle is given in the case of a convex functional constrained by linear dynamics. Its relationship to the Kuhn-Tucker saddle point theory is indicated. Applications to various programming and control problems are discussed.
Aspects of Gauge-Gravity Duality and Holography
NASA Astrophysics Data System (ADS)
Samani, Joshua Fred
We study three aspects of gauge-gravity duality. First, we explore holographic models of conformal field theories with boundary by way of holographic renormalization group flows. Second, we propose an extension and application of the covariant holographic entangelement entropy proposal to warped anti-de-Sitter spacetimes. Third, we exhibit the existence of higher-spin black holes with Lifshitz asymptotics in the Chern-Simons formulation of higher spin gravity.
Solution of coupled and singular perturbation methods using duality theory.
NASA Technical Reports Server (NTRS)
Chan, W. L.; Leininger, G. G.
1973-01-01
Dual variational techniques developed by Chan and Leininger (1972) are summarized, and duality theory in the form of the Complementary Variational Principle is employed to provide a suboptimal measure for the singular and epsilon-coupled perturbation methods proposed by Kokotovic and Cruz. The suboptimal measure is independent of any a priori knowledge of the optimal solution, thereby providing an absolute estimate of the performance loss rather than an estimate relative to the unknown optimal solution.
The onset of quark-hadron duality in pion electroproduction.
Navasardyan, T.; Adams, G. S.; Ahnidouch, A.; Angelescu, T.; Arrington, T.; Arrington, J.; Hafidi, K.; Holt, R. J.; Reimer, P.; Schulte, E.; Zheng, X.; Physics; Yerevan Physics Inst.; Rensselaer Polytechnic Inst.; North Carolina A & T Univ.; Bucharest Univ.
2007-01-01
A large data set of charged-pion ({pi}*) electroproduction from both hydrogen and deuterium targets has been obtained spanning the low-energy residual-mass region. These data conclusively show the onset of the quark-hadron duality phenomenon, as predicted for high-energy hadron electroproduction. We construct several ratios from these data to exhibit the relation of this phenomenon to the high-energy factorization ansatz of electron-quark scattering and subsequent quark {yields} pion production mechanisms.
ERIC Educational Resources Information Center
Mehlinger, Howard D.; Patrick, John J.
This text presents high school students with up-to-date findings of social scientists about political behavior in order to increase their political knowledge and sophistication. Case studies which describe the various political activities of typical citizens and political leaders are used throughout the work. Simulations, games, political attitude…
T-duality and scattering of stringy states
NASA Astrophysics Data System (ADS)
Maharana, Jnanadeva
2014-03-01
We present a procedure for application of T-duality transformation on scattering amplitudes of closed bosonic stringy states. These states arise due to compactification of closed string to lower space-time dimensions through dimensional reduction. The amplitude, in the first quantized formalism, is computed by introducing vertex operators. The amplitude is constructed by the standard prescription and the vertex operators are required to respect conformal invariance. Such vertex operators are constructed in the weak field approximation. Therefore, the vertex operators of the stringy states of our interest are to be defined accordingly. We propose a prescription to implement T-duality on the three-point functions and N-point functions. We argue that it is possible to generate new amplitudes through the transformations on a given amplitude just as T-duality transformations can take us to a new set of string vacuum when acted upon an initial set. Explicit examples are given for three-point and four-point functions.
Trigonometric version of quantum-classical duality in integrable systems
NASA Astrophysics Data System (ADS)
Beketov, M.; Liashyk, A.; Zabrodin, A.; Zotov, A.
2016-02-01
We extend the quantum-classical duality to the trigonometric (hyperbolic) case. The duality establishes an explicit relationship between the classical N-body trigonometric Ruijsenaars-Schneider model and the inhomogeneous twisted XXZ spin chain on N sites. Similarly to the rational version, the spin chain data fixes a certain Lagrangian submanifold in the phase space of the classical integrable system. The inhomogeneity parameters are equal to the coordinates of particles while the velocities of classical particles are proportional to the eigenvalues of the spin chain Hamiltonians (residues of the properly normalized transfer matrix). In the rational version of the duality, the action variables of the Ruijsenaars-Schneider model are equal to the twist parameters with some multiplicities defined by quantum (occupation) numbers. In contrast to the rational version, in the trigonometric case there is a splitting of the spectrum of action variables (eigenvalues of the classical Lax matrix). The limit corresponding to the classical Calogero-Sutherland system and quantum trigonometric Gaudin model is also described as well as the XX limit to free fermions.
S-duality in 3D gravity with torsion
Mielke, Eckehard W. . E-mail: ekke@xanum.uam.mx; Maggiolo, Ali A. Rincon
2007-02-15
The deformation of the connection in three spacetime dimensions by the kinematically equivalent coframe is shown to induce a duality between the (Lorentz-) rotational and translational field momenta, for which the coupling to the deformation parameter is inverted. This new kind of strong/weak duality, pertinent to 3D, is instrumental for studying exact solutions of the 3D Poincare gauge field equations and the particle content of propagating modes on a background of constant curvature. For a topological Chern-Simons model of gravity, the propagating modes 'living' on an Anti-de Sitter (AdS) background correspond to real massive particles. Yang-Mills type generalizations and new cubic Lagrangians are found and completely classified in 3D. AdS or black hole type solutions with constant axial torsion emerge, also for these higher-order Lagrangians with new 'exotic' torsion-curvature couplings. Their pattern complies with our S-duality, with new repercussions for the field redefinition of the metric in 3D quantum gravity and the cosmological constant problem.
BPS states in the duality web of the Omega deformation
NASA Astrophysics Data System (ADS)
Hellerman, Simeon; Orlando, Domenico; Reffert, Susanne
2013-06-01
In this note, we study different limits of an Ω-deformed (2, 0) six-dimensional gauge theory realized in an M-theory fluxtrap background. Via a chain of dualities, we connect the Ω-deformed sym to a new four-dimensional gauge theory which we refer to as the reciprocal gauge theory. This theory has several properties in common with Liouville field theory, such as its gauge coupling b 2 = ɛ 2/ ɛ 1, and its behavior under S-duality. Finally, we realize the bps states on the sym side of the agt correspondence and follow them along the chain of dualities. In the fluxtrap frame, we are dealing with two distinct types of states localized in different radial positions, while in the reciprocal frame, we find single states carrying both charges localized in one place which appear to be perturbatively stable. Our microscopic picture of the small- b limit exhibits semiclassically bps bound states, which are not visible at the level of the partition function.
The conditions for the preservation of duality symmetry in a linear medium
NASA Astrophysics Data System (ADS)
van Kruining, Koen; Götte, Jörg B.
2016-08-01
Electric magnetic duality symmetry is well understood in vacuum. For light propagating through a medium this symmetry is typically broken. We investigate under what conditions duality symmetry is preserved in a linear medium and employ these conditions to generalise the definition of optical helicity to a general linear medium. We will discuss some unique properties duality symmetric media possess, provided they exist, and reformulate Maxwell’s equation in such a way that they explicitly show the decoupling of opposite helicities. The feasibility of constructing a duality symmetric medium is discussed.
Spectral dualities in XXZ spin chains and five dimensional gauge theories
NASA Astrophysics Data System (ADS)
Mironov, A.; Morozov, A.; Runov, B.; Zenkevich, Y.; Zotov, A.
2013-12-01
Motivated by recent progress in the study of supersymmetric gauge theories we propose a very compact formulation of spectral duality between XXZ spin chains. The action of the quantum duality is given by the Fourier transform in the spectral parameter. We investigate the duality in various limits and, in particular, prove it for q → 1, i.e. when it reduces to the XXX/Gaudin duality. We also show that the universal difference operators are given by the normal ordering of the classical spectral curves.
On powercounting in perturbative quantum gravity theories through color-kinematic duality
NASA Astrophysics Data System (ADS)
Boels, Rutger H.; Isermann, Reinke Sven
2013-06-01
The standard argument why gravity is not renormalisable relies on direct powercounting of Feynman graphs to estimate the degree of UV divergence. In several (highly) supersymmetric examples the actual divergences have been shown to be considerably better. In these examples the improvement follows from a conjectured duality between color and kinematics. In this paper we initiate the systematic study of quite general powercounting under the assumption that color-kinematic duality exists. The main technical tool is a reformulation of the duality in terms of linear maps, modulo subtleties at loop level mostly inherent to the duality. This tool may have wider applications in both gauge and gravity theories, up to resolution of the subtleties. Here it is first applied to the large Britto-Cachazo-Feng-Witten (BCFW) shift behavior of gravity integrands constructed through the duality. Assuming color-kinematic duality and reasonable technical requirements hold these shifts are shown to be independent of loop order. This is a new quantitative measure for massive cancellations with respect to the Feynman graph expression. More speculatively, the same approach is then applied to provide estimates of the overall degree of UV divergence in quite general gravity theories, assuming the duality exists. The manifest cancellations obtained in these estimates depends on the exact implementation of the duality at loop level, especially on graph topology. The developed arguments apply to all multiplicity. Finally, some evidence for the duality to all loop orders is provided from an analysis of BCFW shifts of gauge theory integrands through Feynman graphs.
Quark-Hadron Duality and the Transition to pQCD
NASA Astrophysics Data System (ADS)
Fantoni, Alessandra.; Liuti, Simonetta; Rondón, Oscar A.
2006-02-01
Introduction and review: experimental and theoretical status. Introductory remarks on duality in Lepton-Hadron scattering / C. E. Carlson. Duality in the polarized structure functions / H. P. Blok. Spin structure of the nucleon and aspects of duality / Z. E. Meziani -- Duality and confinement. Quark models of duality in electron and neutrino scattering / W. Melnitchouk. Recent predictions from the statistical parton distributions / J. Soffer. Hadron structure on the back of an envelope / A. W. Thomas, R. D. Young and D. B. Leinweber. The strong coupling constant at low Q[symbol] / A. Deur. Spin duality on the neutron ([symbol]He) / P. Solvignon. Local duality in spin structure functions [symbol] and [symbol] / Y. Prok. Spin-flavor decomposition and in polarized semi-inclusive deep inelastic scattering experiments at Jefferson Lab / X. Jiang. Spin structure functions: proton/deuteron measurements in the resonance region / M. K. Jones -- Duality in photoproduction. Duality in vector-meson production / A. Donnachie. Photopion production from nucleon and scaling / H. Gao and D. Dutta. Onset of scaling in exclusive processes / M. Mirazita. Exclusive baryon-antibaryon production in [symbol]-[symbol] at e[symbol]e[symbol] colliders / T. Barillari. Photoabsorption and photoproduction on nuclei in the resonance region / S. Schadmand -- Duality in nuclei. A partonic picture of jet fragmentation in nuclei / X.-N. Wang. Hadron attenuation by (Pre-)hadronic final state interaction at HERMES / T. Falter, K. Gallmeister and U. Mosel. Quark gluon plasma and hadronic gas on the lattice / M. P. Lombardo -- Duality in neutrino experiments. Neutrinos and local duality / F. Steffens and K. Tsushima -- Duality and QCD. Higher twist effects in polarized DIS / E. Leader, A. V. Sidorov and D. B. Stamenov. Higher twist effects in polarized experiments / N. Liyanage. Status of polarized and unpolarized deep inelastic scattering / J. Blümlein. The transition between perturbative and non
A Variant of K-Theory and Topological T-Duality for Real Circle Bundles
NASA Astrophysics Data System (ADS)
Gomi, Kiyonori
2015-03-01
For a space with involutive action, there is a variant of K-theory. Motivated by T-duality in type II orbifold string theory, we establish that a twisted version of the variant enjoys a topological T-duality for Real circle bundles, i.e., circle bundles with real structure.
ERIC Educational Resources Information Center
Neckerman, Kathryn M.
2000-01-01
Examines two books, "The Color of School Reform: Race, Politics, and the Challenge of Urban Education" and "Black Social Capital: The Politics of School Reform in Baltimore," both of which apply urban regime theory to a new policy arena, reconsider the role of business in local school politics, bring politics into institutionalist analysis of…
ERIC Educational Resources Information Center
Chimombo, Moira
1999-01-01
Surveys the interrelationship between language and politics. Touches on the context of political discourse, or political culture and ideology in new and old democracies and the reemerging manifestations of totalitarianism, censorship, and linguistic imperialism; then examines selected linguistic features of political discourse and their…
Talking Politics, Practicing Citizenship
ERIC Educational Resources Information Center
MacKinnon, Mary Pat
2008-01-01
The message emerging from a recent research series on youth civic and political participation is clear: today's youth are not disengaged from associational and small "p" political life, but they are increasingly disenchanted with formal political institutions and practices. Generation Y (those born after 1979) has less formal political knowledge…
Cluster Algebras from Dualities of 2d = (2, 2) Quiver Gauge Theories
NASA Astrophysics Data System (ADS)
Benini, Francesco; Park, Daniel S.; Zhao, Peng
2015-11-01
We interpret certain Seiberg-like dualities of two-dimensional = (2,2) quiver gauge theories with unitary groups as cluster mutations in cluster algebras, originally formulated by Fomin and Zelevinsky. In particular, we show how the complexified Fayet-Iliopoulos parameters of the gauge group factors transform under those dualities and observe that they are in fact related to the dual cluster variables of cluster algebras. This implies that there is an underlying cluster algebra structure in the quantum Kähler moduli space of manifolds constructed from the corresponding Kähler quotients. We study the S 2 partition function of the gauge theories, showing that it is invariant under dualities/mutations, up to an overall normalization factor, whose physical origin and consequences we spell out in detail. We also present similar dualities in = (2,2)* quiver gauge theories, which are related to dualities of quantum integrable spin chains.
Duality between preferential attachment and static networks on hyperbolic spaces
NASA Astrophysics Data System (ADS)
Ferretti, L.; Cortelezzi, M.; Mamino, M.
2014-02-01
There is a complex relation between the mechanism of preferential attachment, scale-free degree distributions and hyperbolicity in complex networks. In fact, both preferential attachment and hidden hyperbolic spaces often generate scale-free networks. We show that there is actually a duality between a class of growing spatial networks based on preferential attachment on the sphere and a class of static random networks on the hyperbolic plane. Both classes of networks have the same scale-free degree distribution as the Barabasi-Albert model. As a limit of this correspondence, the Barabasi-Albert model is equivalent to a static random network on an hyperbolic space with infinite curvature.
Quark-Hadron Duality for the Pion: a Phenomenological Study
Wally Melnitchouk
2002-08-01
We explore the relationship between exclusive and inclusive electromagnetic scattering from the pion, focusing on the transition region at intermediate Q{sup 2}. Combining Drell-Yan data on the leading twist quark distribution in the pion with a model for the resonance region at large x, we calculate QCD moments of the pion structure function over a range of Q{sup 2}, and quantify the role of higher twist corrections. Using a parameterization of the pion elastic form factor and phenomenological models for the pi --> p transition form factor, we test the extent to which local duality may be valid for the pion.
Dualities between semiclassical strings and quantum gauge field theories
NASA Astrophysics Data System (ADS)
Ouyang, Peter
In this thesis we study several examples of the correspondence between gauge field theories and string theories. A recurrent theme of these studies is that distinctively quantum mechanical behavior on the gauge theory side of the correspondence can have a classical or semiclassical description in terms of string calculations, as one might expect from general considerations of open/closed duality. We begin in Chapter 1 by reviewing the simplest duality, which relates Type IIB supergravity in AdS5 x S5 to N = 4 SU(N) gauge theory at large N. Working with this background spacetirne, we turn to a study of D-brane probes with large quantum numbers in Chapter 2. We employ semiclassical methods to compute the excitation spectrum of these D-branes, including corrections of order 1/N, which are related to loop effects in the dual field theory. In Chapter 3 we discuss the gauge/gravity duals with N = 1 supersymmetry which arise from placing D-branes at a conifold singularity. The inclusion of fractional D3-branes breaks conformal invariance, leading to a rich variety of phenomena in the gauge theory, among them chiral anomalies, a cascade of Seiberg dualities and confinement in the infrared. We pay particular attention to the chiral anomalies of the gauge theory and show that they can be described in terms of classical spontaneous symmetry breaking in the dual string theory. In accord with low-energy confinement in the field theory, almost all of the moduli of the supergravity solution are fixed; we conclude Chapter 3 with some observations on the possibility of stabilizing the volume of the compact space in which the conifold is embedded. Finally, in Chapter 4 we study versions of the conifold theory with D7-branes, which introduce fundamental matter into the gauge theory. By solving the classical supergravity equations of motion we identify a variant of the Klebanov-Strassler duality cascade where the rate of the cascade decreases as the theory flows to low energies.
Numerical Implementation of the Loop-Tree Duality
NASA Astrophysics Data System (ADS)
Buchta, S.
We present a first numerical implementation of the Loop-Tree Duality (LTD) method for the direct numerical computation of multi-leg one-loop Feynman integrals. We discuss in detail the singular structure of the dual integrands and define a suitable contour deformation in the loop three-momentum space to carry out the numerical integration. Then, we apply the LTD method to the computation of ultraviolet and infrared finite integrals, and present explicit results for scalar integrals with up to five external legs (pentagons) and tensor integrals with up to six legs (hexagons). The LTD method features an excellent performance independently of the number of external legs.
Topological twist in four dimensions, R-duality and hyperinstantons
NASA Astrophysics Data System (ADS)
Anselmi, Damiano; Frè, Pietro
1993-08-01
In this paper we continue the programme of topologically twisting N = 2 theories in D = 4, focusing on the coupling of vector multiplets to N = 2 supergravity. We show that in the minimal case, namely when the special geometry prepotential F( X) is a quadratic polynomial, the theory has a so far unknown on-shell U(1) symmetry, that we name R-duality. R-duality is a generalization of the chiral-dual on-shell symmetry of N = 2 pure supergravity and of the R-symmetry of N = 2 super Yang-Mills theory. Thanks to this, the theory can be topologically twisted and topologically shifted, precisely as pure N = 2 supergravity, to yield a natural coupling of topological gravity to topological Yang-Mills theory. The gauge-fixing condition that emerges from the twisting is the self-duality condition on the gauge field strength and on the spin connection. Hence our theory reduces to intersection theory in the moduli-space of gauge instantons living in gravitational instanton backgrounds. We remark that, for deep properties of the parent N = 2 theory, the topological Yang-Mills theory we obtain by taking the flat space limit of our gravity-coupled lagrangian is different from the Donaldson theory constructed by Witten. Whether this difference is substantial and what its geometrical implications may be is yet to be seen. We also discuss the topological twist of the hypermultiplets leading to topological quaternionic sigma-models. The instantons of these models, named by us hyperinstantons, corespond to a notion of triholomorphic mappings discussed in the paper. In all cases the new ghost number is the sum of the old ghost number plus the R-duality charge. The observables described by the theory are briefly discussed. In conclusion, the topological twist of the complete N = 2 theory defines intersection theory in the moduli-space of gauge instantons plus gravitational instantons plus hyperinstantons. This is possibly a new subject for further mathematical investigation.
The Bloom-Gilman duality and leading logarithms
Carlson, C.E.; Mukhopadhyay, N.C.
1994-04-01
The existing inclusive electroproduction data base allows the authors a look at the issue of the relative behaviors of background and resonance excitations, a part of the Bloom-Gilman duality. These data lack accuracy at high Q{sup 2} but establish PQCD scaling in the resonance region and even allow the authors a glimpse at the leading logarithmic corrections due to the gluon radiation and its possible quenching at large W and x. These should inspire better quality experimental tests at facilities like CEBAF II.
Inflation and compactification derived from duality invariant gaugino condensation
Stewart, N.R. )
1992-04-10
Recently it has been demonstrated that the breaking of space-time supersymmetry in the context of string-induced effective actions may be realized in a duality invariant way using gaugino condensates. In this paper, although generically the ground state is a negative minimum, the authors present a toy model of a Hawking-Moss type inflation by invoking a one-loop Casimir effect and adjusting the cosmological constant to zero. This can only be justified a posteriori since the authors obtain inflation and compactification of the target space albeit fine-tuning is necessary.
Cohomology of toric line bundles via simplicial Alexander duality
NASA Astrophysics Data System (ADS)
Jow, Shin-Yao
2011-03-01
We give a rigorous mathematical proof for the validity of the toric sheaf cohomology algorithm conjectured in the recent paper by Blumenhagen, Jurke, Rahn, and Roschy (arXiv:1003.5217). We actually prove not only the original algorithm but also a speed-up version of it. Our proof is independent from (in fact appeared earlier on the arXiv than) the proof by Roschy and Rahn (arXiv:1006.2392), and has several advantages such as being shorter and cleaner and can also settle the additional conjecture on "Serre duality for Betti numbers" which was raised but unresolved in arXiv:1006.2392.
A duality framework for stochastic optimal control of complex systems
Malikopoulos, Andreas A.
2016-01-01
In this study, we address the problem of minimizing the long-run expected average cost of a complex system consisting of interactive subsystems. We formulate a multiobjective optimization problem of the one-stage expected costs of the subsystems and provide a duality framework to prove that the control policy yielding the Pareto optimal solution minimizes the average cost criterion of the system. We provide the conditions of existence and a geometric interpretation of the solution. For practical situations having constraints consistent with those studied here, our results imply that the Pareto control policy may be of value when we seek to derive online the optimal control policy in complex systems.
Onset of Quark-Hadron Duality in Pion Electroproduction
Navasardyan, T.; Asaturyan, R.; Mkrtchyan, H.; Tadevosyan, V.; Adams, G. S.; Kubarovski, V.; Moziak, B.; Stoler, P.; Ungaro, M.; Villano, A.; Ahmidouch, A.; Danagoulian, S.; Angelescu, T.; Malace, S.; Arrington, J.; Hafidi, K.; Holt, R. J.; Reimer, P.; Schulte, E.; Zheng, X.
2007-01-12
A large data set of charged-pion ({pi}{sup {+-}}) electroproduction from both hydrogen and deuterium targets has been obtained spanning the low-energy residual-mass region. These data conclusively show the onset of the quark-hadron duality phenomenon, as predicted for high-energy hadron electroproduction. We construct several ratios from these data to exhibit the relation of this phenomenon to the high-energy factorization ansatz of electron-quark scattering and subsequent quark{yields}pion production mechanisms.
Representation Theory over Tropical Semifield and Langlands Duality
NASA Astrophysics Data System (ADS)
Gerasimov, Anton A.; Lebedev, Dimitri R.
2013-06-01
Recently we propose a class of infinite-dimensional integral representations of classical {{gl}_{ell+1}}-Whittaker functions and local Archimedean local L-factors using two-dimensional topological field theory framework. The local Archimedean Langlands duality was identified in this setting with the mirror symmetry of the underlying topological field theories. In this note we introduce elementary analogs of the Whittaker functions and the Archimedean L-factors given by U ℓ+1-equivariant symplectic volumes of appropriate Kähler U ℓ+1-manifolds. We demonstrate that the functions thus defined have a dual description as matrix elements of representations of monoids {GL_{ell+1}({R}), {R}} being the tropical semifield. We also show that the elementary Whittaker functions can be obtained from the non-Archimedean Whittaker functions over {{Q}_p} by taking the formal limit p→ 1. Hence the elementary special functions constructed in this way might be considered as functions over the mysterious field {{Q}_1}. The existence of two representations for the elementary Whittaker functions, one as an equivariant volume and the other as a matrix element, should be considered as a manifestation of a hypothetical elementary analog of the local Langlands duality for number fields. We would like to note that the elementary local L-factors coincide with L-factors introduced previously by Kurokawa.
Duality groups, automorphic forms, and higher derivative corrections
Lambert, Neil; West, Peter
2007-03-15
We study the higher derivative corrections that occur in type II superstring theories in ten dimensions or less. Assuming invariance under a discrete duality group G(Z) we show that the generic functions of the scalar fields that occur can be identified with automorphic forms. We then give a systematic method to construct automorphic forms from a given group G(Z) together with a chosen subgroup H and a linear representation of G(Z). This construction is based on the theory of nonlinear realizations and we find that the automorphic forms contain the weights of G. We also carry out the dimensional reduction of the generic higher derivative corrections of the IIB theory to three dimensions and find that the weights of E{sub 8} occur generalizing previous results of the authors on M theory. Since the automorphic forms of this theory contain the weights of E{sub 8} we can interpret the occurrence of weights in the dimensional reduction as evidence for an underlying U-duality symmetry.
Bilinear covariants and spinor fields duality in quantum Clifford algebras
Abłamowicz, Rafał; Gonçalves, Icaro; Rocha, Roldão da
2014-10-15
Classification of quantum spinor fields according to quantum bilinear covariants is introduced in a context of quantum Clifford algebras on Minkowski spacetime. Once the bilinear covariants are expressed in terms of algebraic spinor fields, the duality between spinor and quantum spinor fields can be discussed. Thus, by endowing the underlying spacetime with an arbitrary bilinear form with an antisymmetric part in addition to a symmetric spacetime metric, quantum algebraic spinor fields and deformed bilinear covariants can be constructed. They are thus compared to the classical (non quantum) ones. Classes of quantum spinor fields classes are introduced and compared with Lounesto's spinor field classification. A physical interpretation of the deformed parts and the underlying Z-grading is proposed. The existence of an arbitrary bilinear form endowing the spacetime already has been explored in the literature in the context of quantum gravity [S. W. Hawking, “The unpredictability of quantum gravity,” Commun. Math. Phys. 87, 395 (1982)]. Here, it is shown further to play a prominent role in the structure of Dirac, Weyl, and Majorana spinor fields, besides the most general flagpoles and flag-dipoles. We introduce a new duality between the standard and the quantum spinor fields, by showing that when Clifford algebras over vector spaces endowed with an arbitrary bilinear form are taken into account, a mixture among the classes does occur. Consequently, novel features regarding the spinor fields can be derived.
Open/closed string duality and relativistic fluids
NASA Astrophysics Data System (ADS)
Niarchos, Vasilis
2016-07-01
We propose an open/closed string duality in general backgrounds extending previous ideas about open string completeness by Ashoke Sen. Our proposal sets up a general version of holography that works in gravity as a tomographic principle. We argue, in particular, that previous expectations of a supergravity/Dirac-Born-Infeld (DBI) correspondence are naturally embedded in this conjecture and can be tested in a well-defined manner. As an example, we consider the correspondence between open string field theories on extremal D-brane setups in flat space in the large-N , large 't Hooft limit, and asymptotically flat solutions in ten-dimensional type II supergravity. We focus on a convenient long-wavelength regime, where specific effects of higher-spin open string modes can be traced explicitly in the dual supergravity computation. For instance, in this regime we show how the full Abelian DBI action arises from supergravity as a straightforward reformulation of relativistic hydrodynamics. In the example of a (2 +1 )-dimensional open string theory this reformulation involves an Abelian Hodge duality. We also point out how different deformations of the DBI action, related to higher-derivative corrections and non-Abelian effects, can arise in this context as deformations in corresponding relativistic hydrodynamics.
Bilinear covariants and spinor fields duality in quantum Clifford algebras
NASA Astrophysics Data System (ADS)
Abłamowicz, Rafał; Gonçalves, Icaro; da Rocha, Roldão
2014-10-01
Classification of quantum spinor fields according to quantum bilinear covariants is introduced in a context of quantum Clifford algebras on Minkowski spacetime. Once the bilinear covariants are expressed in terms of algebraic spinor fields, the duality between spinor and quantum spinor fields can be discussed. Thus, by endowing the underlying spacetime with an arbitrary bilinear form with an antisymmetric part in addition to a symmetric spacetime metric, quantum algebraic spinor fields and deformed bilinear covariants can be constructed. They are thus compared to the classical (non quantum) ones. Classes of quantum spinor fields classes are introduced and compared with Lounesto's spinor field classification. A physical interpretation of the deformed parts and the underlying {Z}-grading is proposed. The existence of an arbitrary bilinear form endowing the spacetime already has been explored in the literature in the context of quantum gravity [S. W. Hawking, "The unpredictability of quantum gravity," Commun. Math. Phys. 87, 395 (1982)]. Here, it is shown further to play a prominent role in the structure of Dirac, Weyl, and Majorana spinor fields, besides the most general flagpoles and flag-dipoles. We introduce a new duality between the standard and the quantum spinor fields, by showing that when Clifford algebras over vector spaces endowed with an arbitrary bilinear form are taken into account, a mixture among the classes does occur. Consequently, novel features regarding the spinor fields can be derived.
The duality principle in the presence of postselection
Leach, Jonathan; Bolduc, Eliot; Miatto, Filippo M.; Piché, Kevin; Leuchs, Gerd; Boyd, Robert W.
2016-01-01
The duality principle, a cornerstone of quantum mechanics, limits the coexistence of wave and particle behaviours of quantum systems. This limitation takes a quantitative form when applied to the visibility of interference fringes and predictability of paths within a two-alternative system, which are bound by the inequality . However, if such a system is coupled to its environment, it becomes possible to obtain conditional measures of visibility and predictability, i.e. measures that are conditioned on the state of the environment. We show that in this case, the predictability and visibility values can lead to an apparent violation of the duality principle. We experimentally realize this apparent violation in a controlled manner by enforcing a fair-sampling-like loophole via postselection. This work highlights some of the subtleties that one can encounter while interpreting familiar quantities such as which-alternative information and visibility. While we concentrated on an extreme example, it is of utmost importance to realise that such subtleties might also be present in cases where the results are not obviously violating an algebraic bound, making them harder (but not any less crucial) to detect. PMID:26821619
The duality principle in the presence of postselection
NASA Astrophysics Data System (ADS)
Leach, Jonathan; Bolduc, Eliot; Miatto, Filippo M.; Piché, Kevin; Leuchs, Gerd; Boyd, Robert W.
2016-01-01
The duality principle, a cornerstone of quantum mechanics, limits the coexistence of wave and particle behaviours of quantum systems. This limitation takes a quantitative form when applied to the visibility of interference fringes and predictability of paths within a two-alternative system, which are bound by the inequality . However, if such a system is coupled to its environment, it becomes possible to obtain conditional measures of visibility and predictability, i.e. measures that are conditioned on the state of the environment. We show that in this case, the predictability and visibility values can lead to an apparent violation of the duality principle. We experimentally realize this apparent violation in a controlled manner by enforcing a fair-sampling-like loophole via postselection. This work highlights some of the subtleties that one can encounter while interpreting familiar quantities such as which-alternative information and visibility. While we concentrated on an extreme example, it is of utmost importance to realise that such subtleties might also be present in cases where the results are not obviously violating an algebraic bound, making them harder (but not any less crucial) to detect.
The origins of duality of patterning in artificial whistled languages
Verhoef, Tessa
2012-01-01
In human speech, a finite set of basic sounds is combined into a (potentially) unlimited set of well-formed morphemes. Hockett (1960) placed this phenomenon under the term ‘duality of patterning’ and included it as one of the basic design features of human language. Of the thirteen basic design features Hockett proposed, duality of patterning is the least studied and it is still unclear how it evolved in language. Recent work shedding light on this is summarized in this paper and experimental data is presented. This data shows that combinatorial structure can emerge in an artificial whistled language through cultural transmission as an adaptation to human cognitive biases and learning. In this work the method of experimental iterated learning (Kirby et al. 2008) is used, in which a participant is trained on the reproductions of the utterances the previous participant learned. Participants learn and recall a system of sounds that are produced with a slide whistle. Transmission from participant to participant causes the whistle systems to change and become more learnable and more structured. These findings follow from qualitative observations, quantitative measures and a follow-up experiment that tests how well participants can learn the emerged whistled languages by generalizing from a few examples. PMID:23637710
Path integral duality modified propagators in spacetimes with constant curvature
Kothawala, Dawood; Padmanabhan, T.; Sriramkumar, L.; Shankaranarayanan, S.
2009-08-15
The hypothesis of path integral duality provides a prescription to evaluate the propagator of a free, quantum scalar field in a given classical background, taking into account the existence of a fundamental length, say, the Planck length L{sub P} in a locally Lorentz invariant manner. We use this prescription to evaluate the duality modified propagators in spacetimes with constant curvature (exactly in the case of one spacetime, and in the Gaussian approximation for another two), and show that (i) the modified propagators are ultraviolet finite, (ii) the modifications are nonperturbative in L{sub P}, and (iii) L{sub P} seems to behave like a 'zero point length' of spacetime intervals such that <{sigma}{sup 2}(x,x{sup '})>=[{sigma}{sup 2}(x,x{sup '})+O(1)L{sub P}{sup 2}], where {sigma}(x,x{sup '}) is the geodesic distance between the two spacetime points x and x{sup '}, and the angular brackets denote (a suitable) average over the quantum gravitational fluctuations. We briefly discuss the implications of our results.
K-theoretic aspects of string theory dualities
NASA Astrophysics Data System (ADS)
Mendez-Diez, Stefan Milo
String theory is a a physical field theory in which point particles are replaced by 1-manifolds propagating in time, called strings. The 2-manifold representing the time evolution of a string is called the string worldsheet. Strings can be either closed (meaning their worldsheets are closed surfaces) or open (meaning their worldsheets have boundary). A D-brane is a submanifold of the spacetime manifold on which string endpoints are constrained to lie. There are five different string theories that have supersymmetry, and they are all related by various dualities. This dissertation will review how D-branes are classified by K-theory. We will then explore the K-theoretic aspects of a hypothesized duality between the type I theory compactified on a 4-torus and the type IIA theory compactified on a K3 surface, by looking at a certain blow down of the singular limit of K3. This dissertation concludes by classifying D-branes on the type II orientifold Tn/Z2 when the Z2 action is multiplication by -1 and the H-flux is trivial. We find that classifying D-branes on the singular limit of K3, T4/Z2 by equivariant K-theory agrees with the classification of D-branes on a smooth K3 surface by ordinary K-theory.
NASA Astrophysics Data System (ADS)
Ohkubo, Jun
2015-10-01
An alternative application of duality relations of stochastic processes is demonstrated. Although conventional usages of the duality relations need analytical solutions for the dual processes, here I employ numerical solutions of the dual processes and investigate the usefulness. As a demonstration, estimation problems of hidden variables in stochastic differential equations are discussed. Employing algebraic probability theory, a little complicated birth-death process is derived from the stochastic differential equations, and an estimation method based on the ensemble Kalman filter is proposed. As a result, the possibility for making faster computational algorithms based on the duality concepts is shown.
Evidence for quark-hadron duality in {gamma}*p helicity cross sections
Malace, S. P.; Melnitchouk, W.; Psaker, A.
2011-03-15
Combining data on unpolarized and polarized inclusive proton structure functions, we perform the first detailed study of quark-hadron duality in individual helicity-1/2 and 3/2 virtual photoproduction cross sections. We find that duality is realized more clearly in the helicity-1/2 channel, with duality-violating corrections < or approx. 10% over the entire nucleon resonance region, while larger, < or approx. 20% corrections are found in the helicity-3/2 sector. The results are in general agreement with quark model expectations, and suggest that data above the {Delta} resonance region may be used to constrain both spin-averaged and spin-dependent parton distributions.
Ohkubo, Jun
2015-10-01
An alternative application of duality relations of stochastic processes is demonstrated. Although conventional usages of the duality relations need analytical solutions for the dual processes, here I employ numerical solutions of the dual processes and investigate the usefulness. As a demonstration, estimation problems of hidden variables in stochastic differential equations are discussed. Employing algebraic probability theory, a little complicated birth-death process is derived from the stochastic differential equations, and an estimation method based on the ensemble Kalman filter is proposed. As a result, the possibility for making faster computational algorithms based on the duality concepts is shown. PMID:26565359
Self-duality for the two-component asymmetric simple exclusion process
Belitsky, V.; Schütz, G. M.
2015-08-15
We study a two-component asymmetric simple exclusion process (ASEP) that is equivalent to the ASEP with second-class particles. We prove self-duality with respect to a family of duality functions which are shown to arise from the reversible measures of the process and the symmetry of the generator under the quantum algebra U{sub q}[gl{sub 3}]. We construct all invariant measures in explicit form and discuss some of their properties. We also prove a sum rule for the duality functions.
NASA Astrophysics Data System (ADS)
Mross, David F.; Alicea, Jason; Motrunich, Olexei I.
2016-07-01
We explicitly derive the duality between a free electronic Dirac cone and quantum electrodynamics in (2 +1 ) dimensions (QED3 ) with N =1 fermion flavors. The duality proceeds via an exact, nonlocal mapping from electrons to dual fermions with long-range interactions encoded by an emergent gauge field. This mapping allows us to construct parent Hamiltonians for exotic topological-insulator surface phases, derive the particle-hole-symmetric field theory of a half-filled Landau level, and nontrivially constrain QED3 scaling dimensions. We similarly establish duality between bosonic topological insulator surfaces and N =2 QED3 .
ERIC Educational Resources Information Center
Funderburk, Charles
1978-01-01
Explains how the use of feature-length motion pictures, combined with interesting readings, can generate enthusiasm, discussion, and analysis of basic political ideas, concepts, and values. Reviews costs and identifies specific movies and readings on various political topics. (AV)
ERIC Educational Resources Information Center
Kamin, Leon J.
1975-01-01
Traces social, cultural, economic, and political history shaping intelligence testing with respect to an inheritable intelligence level to conclude that interpretation of IQ has always been in a social and political context. (DW)
ERIC Educational Resources Information Center
Gaskell, Jane
1988-01-01
Explores what it means to do research intended to be relevant for public policy. Argues against perception of policy research as politically neutral technical exercise. Discusses political implications of methodology. Discusses research examples to illustrate point. Discusses implications for how research might be used in political process.…
ERIC Educational Resources Information Center
Dag, Nilgun; Sozer, Mehmet Akif; Sel, Burcu
2015-01-01
Political education is a term with negative associations and triggering prejudiced approaches and discourses--maybe some paranoid thoughts--like "keep politics away from education!" in the minds of several people. This article deals with "political education" phenomenon almost never discussed and made subject to scientific…
Unique Rural District Politics
ERIC Educational Resources Information Center
Farmer, Tod Allen
2009-01-01
The politics of rural educational leadership are both intense and concentrated. Rural educational leaders need to be savvy and politically skilled if they are to inspire educational stakeholders and accomplish organizational objectives. The local school system is an organization with a political culture that can be characterized as a competitive…
ERIC Educational Resources Information Center
Moreira, Silvio; Batista, David S.; Carvalho, Paula; Couto, Francisco M.; Silva, Mario J.
2013-01-01
Purpose: POWER is an ontology of political processes and entities. It is designed for tracking politicians, political organizations and elections, both in mainstream and social media. The aim of this paper is to propose a data model to describe political agents and their relations over time. Design/methodology/approach: The authors propose a data…
NASA Astrophysics Data System (ADS)
Metlitski, Max A.; Vishwanath, Ashvin
2016-06-01
Particle-vortex duality is a powerful theoretical tool that has been used to study bosonic systems. Here, we propose an analogous duality for Dirac fermions in 2+1 dimensions. The physics of a single Dirac cone is proposed to be described by a dual theory, QED3, with again a single Dirac fermion but coupled to a gauge field. This duality is established by considering two alternate descriptions of the three-dimensional topological insulator (TI) surface. The first description is the usual Dirac fermion surface state. The dual description is accessed via an electric-magnetic duality of the bulk TI coupled to a gauge field, which maps it to a gauged chiral topological insulator. This alternate description ultimately leads to a new surface theory, QED3, which provides a simple description of otherwise intractable interacting electronic states. For example, an explicit derivation of the T-Pfaffian state, a proposed surface topological order of the TI, is obtained by simply pair condensing the dual fermions. The roles of time-reversal and particle-hole symmetries are exchanged by the duality, which connects some of our results to a recent conjecture by Son on particle-hole symmetric quantum Hall states.
Flux-concentration duality in dynamic nonequilibrium biological networks.
Jamshidi, Neema; Palsson, Bernhard Ø
2009-09-01
The structure of dynamic states in biological networks is of fundamental importance in understanding their function. Considering the elementary reaction structure of reconstructed metabolic networks, we show how appreciation of a gradient matrix, G =dv/dx (where v is the vector of fluxes and x is the vector of concentrations), enables the formulation of dual Jacobian matrices. One is for concentrations, J(x) =S x G, and the other is for fluxes, J(v) =G x S. The fundamental properties of these two Jacobians and the underlying duality that relates them are delineated. We describe a generalized approach to decomposing reaction networks in terms of the thermodynamic and kinetic components in the context of the network structure. The thermodynamic and kinetic influences can be viewed in terms of direction-driver relationships in the network. PMID:19720010
Subdiffusive and superdiffusive quantum transport and generalized duality
Sassetti, M.; Schomerus, H.; Weiss, U.
1996-02-01
As a generic model for transport of interacting fermions through a barrier or interstitials in a lattice, quantum Brownian motion in a periodic potential is studied. There is a duality transformation between the continuous coordinate or phase representation and the discrete momentum or charge representation for general frequency-dependent damping. Sub-Ohmic friction is mapped on super-Ohmic friction, and vice versa. The mapping is exact for arbitrary barrier height and valid at any temperature. Thus all features of the continuous model can be investigated from analytical or numerical analysis of the discrete model. Nonperturbative results for the frequency-dependent linear mobility including subdiffusive and superdiffusive behaviors are reported. {copyright} {ital 1996 The American Physical Society.}
D-branes, gauge/string duality and noncommutative theories
NASA Astrophysics Data System (ADS)
Mateos, Toni
2004-09-01
In this thesis we elaborate on the three subjects of the title. We first show that supertubes exist and still preserve some supersymmetry in a large variety of curved backgrounds. Within the AdS/CFT correspondence we study the supersymmetry of rotating strings with 3 angular momenta, and we consider the possibility of adding matter in a stable but non-supersymmetric way. We contribute to the extension of the duality to more realistic YM theories by constructing the sugra dual of an N=2 pure SYM in 3d, given in terms of a Calabi-Yau four-fold in M-theory. We study the unitarity of noncommutative nonrelativistic field theories, we construct the sugra dual of noncommutative pure SYM theories with N=1 in 4d and N=2 in 3d, and we study holographically properties like UV/IR mixing, confinement, chiral symmetry breaking and moduli spaces.
Equivalence of wave-particle duality to entropic uncertainty.
Coles, Patrick J; Kaniewski, Jedrzej; Wehner, Stephanie
2014-01-01
Interferometers capture a basic mystery of quantum mechanics: a single particle can exhibit wave behaviour, yet that wave behaviour disappears when one tries to determine the particle's path inside the interferometer. This idea has been formulated quantitatively as an inequality, for example, by Englert and Jaeger, Shimony and Vaidman, which upper bounds the sum of the interference visibility and the path distinguishability. Such wave-particle duality relations (WPDRs) are often thought to be conceptually inequivalent to Heisenberg's uncertainty principle, although this has been debated. Here we show that WPDRs correspond precisely to a modern formulation of the uncertainty principle in terms of entropies, namely, the min- and max-entropies. This observation unifies two fundamental concepts in quantum mechanics. Furthermore, it leads to a robust framework for deriving novel WPDRs by applying entropic uncertainty relations to interferometric models. As an illustration, we derive a novel relation that captures the coherence in a quantum beam splitter. PMID:25524138
Superconductivity from gauge/gravity duality with flavor
NASA Astrophysics Data System (ADS)
Ammon, Martin; Erdmenger, Johanna; Kaminski, Matthias; Kerner, Patrick
2009-10-01
We consider thermal strongly-coupled N = 2 SYM theory with fundamental matter at finite isospin chemical potential. Using gauge/gravity duality, i.e. a probe of two flavor D7-branes embedded in the AdS black hole background, we find a critical temperature at which the system undergoes a second order phase transition. The critical exponent of this transition is one half and coincides with the result from mean field theory. In the thermodynamically favored phase, a flavor current acquires a vev and breaks an Abelian symmetry spontaneously. This new phase shows signatures known from superconductivity, such as an infinite dc conductivity and a gap in the frequency-dependent conductivity. The gravity setup allows for an explicit identification of the degrees of freedom in the dual field theory, as well as for a dual string picture of the condensation process.
Coherence-path duality relations for N paths
NASA Astrophysics Data System (ADS)
Hillery, Mark; Bagan, Emilio; Bergou, Janos; Cottrell, Seth
2016-05-01
For an interferometer with two paths, there is a relation between the information about which path the particle took and the visibility of the interference pattern at the output. The more path information we have, the smaller the visibility, and vice versa. We generalize this relation to a multi-path interferometer, and we substitute two recently defined measures of quantum coherence for the visibility, which results in two duality relations. The path information is provided by attaching a detector to each path. In the first relation, which uses an l1 measure of coherence, the path information is obtained by applying the minimum-error state discrimination procedure to the detector states. In the second, which employs an entropic measure of coherence, the path information is the mutual information between the detector states and the result of measuring them. Both approaches are quantitative versions of complementarity for N-path interferometers. Support provided by the John Templeton Foundation.
Dyonic ISO(7) supergravity and the duality hierarchy
NASA Astrophysics Data System (ADS)
Guarino, Adolfo; Varela, Oscar
2016-02-01
Motivated by its well defined higher dimensional origin, a detailed study of D = 4 {N}=8 supergravity with a dyonically gauged ISO(7)=SO(7)ltimes {{R}}^7 gauge group is performed. We write down the Lagrangian and describe the tensor and duality hierarchies, focusing on an interesting subsector with closed field equations and supersymmetry transformations. We then truncate the {N}=8 theory to some smaller sectors with {N}=2 and {N}=1 supersymmetry and SU(3), G2 and SO(4) bosonic symmetry. Canonical and superpotential formulations for these sectors are given, and their vacuum structure and spectra is analysed. Unlike the purely electric ISO(7) gauging, the dyonic gauging displays a rich structure of vacua, all of them AdS. We recover all previously known ones and find a new {N}=1 vacuum with SU(3) symmetry and various non-supersymmetric vacua, all of them stable within the full {N}=8 theory.
Superconformal block quivers, duality trees and Diophantine equations
NASA Astrophysics Data System (ADS)
Hanany, Amihay; He, Yang-Hui; Sun, Chuang; Sypsas, Spyros
2013-11-01
We generalize previous results on = 1, (3 + 1)-dimensional superconformal block quiver gauge theories. It is known that the necessary conditions for a theory to be superconformal, i.e. that the beta and gamma functions vanish in addition to anomaly cancellation, translate to a Diophantine equation in terms of the quiver data. We re-derive results for low block numbers revealing an new intriguing algebraic structure underlying a class of possible superconformal fixed points of such theories. After explicitly computing the five block case Diophantine equation, we use this structure to reorganize the result in a form that can be applied to arbitrary block numbers. We argue that these theories can be thought of as vectors in the root system of the corresponding quiver and superconformality conditions are shown to associate them to certain subsets of imaginary roots. These methods also allow for an interpretation of Seiberg duality as the action of the affine Weyl group on the root lattice.
Warped AdS3/dipole-CFT duality
NASA Astrophysics Data System (ADS)
Song, Wei; Strominger, Andrew
2012-05-01
String theory contains solutions with {{SL}}( {{2},{R}} ){{R}} × {{U}}{( {1} )_L} -invariant warped AdS3 (WAdS3) factors arising as continuous deformations of ordinary AdS3 factors. We propose that some of these are holographically dual to the IR limits of nonlocal dipole-deformed 2D D-brane gauge theories, referred to as "dipole CFTs". Neither the bulk nor boundary theories are currently well-understood, and consequences of the proposed duality for both sides is investigated. The bulk entropy-area law suggests that dipole CFTs have (at large N) a high-energy density of states which does not depend on the deformation parameter. Putting the boundary theory on a spatial circle leads to closed timelike curves in the bulk, suggesting a relation of the latter to dipole-type nonlocality.
K3-fibrations and heterotic-type II string duality
NASA Astrophysics Data System (ADS)
Klemm, A.; Lerche, W.; Mayr, P.
1995-02-01
We analyze the map between heterotic and type II N = 2 supersymmetric string theories for certain two and three moduli examples found by Kachru and Vafa. The appearance of elliptic j-functions can be traced back to specializations of the Picard-Fuchs equations to systems for K3 surfaces. For the three-moduli example we write the mirror maps and Yukawa couplings in the weak coupling limit in terms of j-functions; the expressions agree with those obtained in perturbative calculations in the heterotic string in an impressive way. We also discuss symmetries of the world-sheet instanton numbers in the type II theory, and interpret them in terms of S-duality of the non-perturbative heterotic string.
Inference in infinite-dimensional inverse problems - Discretization and duality
NASA Technical Reports Server (NTRS)
Stark, Philip B.
1992-01-01
Many techniques for solving inverse problems involve approximating the unknown model, a function, by a finite-dimensional 'discretization' or parametric representation. The uncertainty in the computed solution is sometimes taken to be the uncertainty within the parametrization; this can result in unwarranted confidence. The theory of conjugate duality can overcome the limitations of discretization within the 'strict bounds' formalism, a technique for constructing confidence intervals for functionals of the unknown model incorporating certain types of prior information. The usual computational approach to strict bounds approximates the 'primal' problem in a way that the resulting confidence intervals are at most long enough to have the nominal coverage probability. There is another approach based on 'dual' optimization problems that gives confidence intervals with at least the nominal coverage probability. The pair of intervals derived by the two approaches bracket a correct confidence interval. The theory is illustrated with gravimetric, seismic, geomagnetic, and helioseismic problems and a numerical example in seismology.
T-duality via gerby geometry and reductions
NASA Astrophysics Data System (ADS)
Bunke, Ulrich; Nikolaus, Thomas
2015-06-01
We consider topological T-duality of torus bundles equipped with {S}1-gerbes. We show how a geometry on the gerbe determines a reduction of its band to the subsheaf of S1-valued functions which are constant along the torus fibers. We observe that such a reduction is exactly the additional datum needed for the construction of a T-dual pair. We illustrate the theory by working out the example of the canonical lifting gerbe on a compact Lie group which is a torus bundle over the associated flag manifold. It was a recent observation of Daenzer and van Erp [16] that for certain compact Lie groups and a particular choice of the gerbe, the T-dual torus bundle is given by the Langlands dual group.
Entropic framework for wave-particle duality in multipath interferometers
NASA Astrophysics Data System (ADS)
Coles, Patrick J.
2016-06-01
An interferometer—no matter how clever the design—cannot reveal both the wave and the particle behavior of a quantum system. This fundamental idea has been captured by inequalities, so-called wave-particle duality relations (WPDRs), that upper bound the sum of the fringe visibility (wave behavior) and path distinguishability (particle behavior). Another fundamental idea is Heisenberg's uncertainty principle, stating that some pairs of observables cannot be known simultaneously. Recent work has unified these two principles for two-path interferometers. Here we extend this unification to n -path interferometers, showing that WPDRs correspond to a modern formulation of the uncertainty principle stated in terms of entropies. Furthermore, our unification provides a framework for solving an outstanding problem of how to formulate universally valid WPDRs for interferometers with more than two paths, and we employ this framework to derive some novel WPDRs.
Equivalence of wave-particle duality to entropic uncertainty
NASA Astrophysics Data System (ADS)
Coles, Patrick J.; Kaniewski, Jedrzej; Wehner, Stephanie
2014-12-01
Interferometers capture a basic mystery of quantum mechanics: a single particle can exhibit wave behaviour, yet that wave behaviour disappears when one tries to determine the particle’s path inside the interferometer. This idea has been formulated quantitatively as an inequality, for example, by Englert and Jaeger, Shimony and Vaidman, which upper bounds the sum of the interference visibility and the path distinguishability. Such wave-particle duality relations (WPDRs) are often thought to be conceptually inequivalent to Heisenberg’s uncertainty principle, although this has been debated. Here we show that WPDRs correspond precisely to a modern formulation of the uncertainty principle in terms of entropies, namely, the min- and max-entropies. This observation unifies two fundamental concepts in quantum mechanics. Furthermore, it leads to a robust framework for deriving novel WPDRs by applying entropic uncertainty relations to interferometric models. As an illustration, we derive a novel relation that captures the coherence in a quantum beam splitter.
Wave-Particle Duality: An Information-Based Approach
NASA Astrophysics Data System (ADS)
Angelo, R. M.; Ribeiro, A. D.
2015-11-01
Recently, Bohr's complementarity principle was assessed in setups involving delayed choices. These works argued in favor of a reformulation of the aforementioned principle so as to account for situations in which a quantum system would simultaneously behave as wave and particle. Here we defend a framework that, supported by well-known experimental results and consistent with the decoherence paradigm, allows us to interpret complementarity in terms of correlations between the system and an informer. Our proposal offers formal definition and operational interpretation for the dual behavior in terms of both nonlocal resources and the couple work-information. Most importantly, our results provide a generalized information-based trade-off for the wave-particle duality and a causal interpretation for delayed-choice experiments.
Antisymmetric tensor field and spontaneous magnetization in holographic duality
NASA Astrophysics Data System (ADS)
Cai, Rong-Gen; Yang, Run-Qiu
2015-08-01
A real antisymmetric tensor field was introduced to realize a holographic magnetic ordered phase in our previous papers. However, a more careful analysis shows there is a vector ghost in the model. In this paper we present a modified Lagrangian density for the antisymmetric tensor, which is ghost free and causality is well defined, and keeps all the significant results in the original model qualitatively. We show this modified Lagrangian density could come from the dimensional compactification of p -form field in string/M theory. For static curved space-time, we also prove that this modified model is ghost free and does not violate causality. This new model offers a solid foundation for the application of antisymmetric tensor field in holographic duality, especially for the spontaneous magnetization.
Origin of Money: Dynamic Duality Between Necessity and Unnecessity
NASA Astrophysics Data System (ADS)
Tauchi, Yuka; Kamiura, Moto; Haruna, Taichi; Gunji, Yukio-Pegio
2008-10-01
We propose a mathematical model of economic agents to study origin of money. This multi-agent model is based on commodity theory of money, which says that a commodity used as money emerges from barter transaction. Each agent has a different value system which is given by a Heyting algebra, and exchanges one's commodities based on the value system. In each value system, necessity and unnecessity of commodities are expressed by some elements and their compliments on a Heyting Algebra. Moreover, the concept of the compliment is extended. Consequently, the duality of the necessity-unnecessity is weakened, and the exchanges of the commodities are promoted. The commodities which keeps being exchanged for a long time can correspond to money.
De Sitter space in gauge/gravity duality
NASA Astrophysics Data System (ADS)
Anguelova, Lilia; Suranyi, Peter; Wijewardhana, L. C. R.
2015-10-01
We investigate gauge/gravity duality for gauge theories in de Sitter space. More precisely, we study a five-dimensional consistent truncation of type IIB supergravity, which encompasses a wide variety of gravity duals of strongly coupled gauge theories, including the Maldacena-Nunez solution and its walking deformations. We find several solutions of the 5d theory with dS4 spacetime and nontrivial profiles for (some of) the scalars along the fifth (radial) direction. In the process, we prove that one of the equations of motion becomes dependent on the others, for nontrivial warp factor. This dependence reduces the number of field equations and, thus, turns out to be crucial for the existence of solutions with (A) dS 4 spacetime. Finally, we comment on the implications of our dS4 solutions for building gravity duals of Glueball Inflation.
Deeply virtual Compton scattering from gauge/gravity duality
Costa, Miguel S.; Djuric, Marko
2013-04-15
We use gauge/gravity duality to study deeply virtual Compton scattering (DVCS) in the limit of high center of mass energy at fixed momentum transfer, corresponding to the limit of low Bjorken x, where the process is dominated by the exchange of the pomeron. At strong coupling, the pomeron is described as the graviton Regge trajectory in AdS space, with a hard wall to mimic confinement effects. This model agrees with HERA data in a large kinematical range. The behavior of the DVCS cross section for very high energies, inside saturation, can be explained by a simple AdS black disk model. In a restricted kinematical window, this model agrees with HERA data as well.
A duality framework for stochastic optimal control of complex systems
Malikopoulos, Andreas A.
2016-01-01
In this study, we address the problem of minimizing the long-run expected average cost of a complex system consisting of interactive subsystems. We formulate a multiobjective optimization problem of the one-stage expected costs of the subsystems and provide a duality framework to prove that the control policy yielding the Pareto optimal solution minimizes the average cost criterion of the system. We provide the conditions of existence and a geometric interpretation of the solution. For practical situations having constraints consistent with those studied here, our results imply that the Pareto control policy may be of value when we seek to derivemore » online the optimal control policy in complex systems.« less
Arbitrary dimensional Majorana dualities and architectures for topological matter
NASA Astrophysics Data System (ADS)
Nussinov, Zohar; Ortiz, Gerardo; Cobanera, Emilio
2012-08-01
Motivated by the prospect of attaining Majorana modes at the ends of nanowires, we analyze interacting Majorana systems on general networks and lattices in an arbitrary number of dimensions, and derive universal spin duals. We prove that these interacting Majorana systems, quantum Ising gauge theories, and transverse-field Ising models with annealed bimodal disorder are all dual to one another on general planar graphs. This leads to an interesting connection between heavily disordered annealed Ising systems and uniform Ising theories with nearest-neighbor interactions. As any Dirac fermion (including electronic) operator can be expressed as a linear combination of two Majorana fermion operators, our results further lead to dualities between interacting Dirac fermionic systems on rather general lattices and graphs and corresponding spin systems. Such general complex Majorana architectures (other than those of simple square or other crystalline arrangements) might be of empirical relevance. As these systems display low-dimensional symmetries, they are candidates for realizing topological quantum order. The spin duals allow us to predict the feasibility of various standard transitions as well as spin-glass-type behavior in interacting Majorana fermion or electronic systems. Several systems that can be simulated by arrays of Majorana wires are further introduced and investigated: (1) the XXZ honeycomb compass model (intermediate between the classical Ising model on the honeycomb lattice and Kitaev's honeycomb model), (2) a checkerboard lattice realization of the model of Xu and Moore for superconducting (p+ip) arrays, and a (3) compass-type two-flavor Hubbard model with both pairing and hopping terms. By the use of our dualities (tantamount to high-dimensional fermionization), we show that all of these systems lie in the three-dimensional Ising universality class. We further discuss how the existence of topological orders and bounds on autocorrelation times can be
Approaches to emergent spacetime in gauge/gravity duality
NASA Astrophysics Data System (ADS)
Sully, James Kenneth
2013-08-01
In this thesis we explore approaches to emergent local spacetime in gauge/gravity duality. We first conjecture that every CFT with a large-N type limit and a parametrically large gap in the spectrum of single-trace operators has a local bulk dual. We defend this conjecture by counting consistent solutions to the four-point function in simple scalar models and matching to the number of local interaction terms in the bulk. Next, we proceed to explicitly construct local bulk operators using smearing functions. We argue that this construction allows one to probe inside black hole horizons for only short times. We then suggest that the failure to construct bulk operators inside a black hole at late times is indicative of a break-down of local effective field theory at the black hole horizon. We argue that the postulates of black hole complementarity are inconsistent and cannot be realized within gauge/gravity duality. We argue that the most conservative solution is a firewall at the black hole horizon and we critically explore alternative resolutions. We then examine the CGHS model of two-dimensional gravity to look for dynamical formation of firewalls. We find that the CGHS model does not exhibit firewalls, but rather contains long-lived remnants. We argue that, while this is consistent for the CGHS model, it cannot be so in higher-dimensional theories of gravity. Lastly, we turn to F-theory, and detail local and global obstructions to writing elliptic fibrations in Tate form. We determine more general possible forms.
Political Science and Political Geography: Neglected Areas, Areas for Development.
ERIC Educational Resources Information Center
Laponce, J. A.
1983-01-01
Since at least the 1950s, political scientists have tended to ignore the possible contributions of political geography to political science because of a move away from considering spatial factors on political structure. Political scientists need to use more information from geography to enhance their understanding of political power and conflict.…
Krakauer, E.
1992-01-01
This paper explores the relationship between medicine and politics, between medical management of the human body and governmental management of the body politic. It argues that the increasing complexity both of society and of governmental administration of society in the modern age has made it impossible completely to separate medicine from politics. It demonstrates that, along with great potential for social benefit, "medico-politics" brought with it great danger; much harm has been done purportedly to heal the body politic. The paper concludes by suggesting a way for physicians to minimize this danger. Images FIG. 1 PMID:1285451
Wave-particle duality and polarization properties of light in single-photon interference experiments
Lahiri, Mayukh
2011-04-15
We consider superposition of two states of light polarized along mutually orthogonal directions. We show that partial polarization of the superposed light may be interpreted as a manifestation of the wave-particle duality.
String duality transformations in f(R) gravity from Noether symmetry approach
NASA Astrophysics Data System (ADS)
Capozziello, Salvatore; Gabriele Gionti S., J.; Vernieri, Daniele
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 are shown in cases where the duality transformation becomes a parity inversion.
Hacker, Jacob S
2008-01-01
The greatest lesson of the failure of comprehensive health reform in the early 1990s is that politics comes first. Even the best-laid policy plans are worthless if they lack the political support to pass. Putting politics first means avoiding the overarching mistake of the Clinton reformers: envisioning a grand policy compromise rather than hammering out a real political compromise. It also means addressing the inevitable fears of those who believe that they are well protected by our eroding employment-based system. And it means formulating political strategies that are premised on the contemporary realities of the hyperpolarized U.S. political environment, rather than wistfully recalled images of the bipartisan politics of old. PMID:18474963
Quark-hadron duality and truncated moments of nucleon structure functions
Psaker, A.; Melnitchouk, W.; Christy, M. E.; Keppel, C.
2008-08-15
We employ a novel new approach to study local quark-hadron duality using 'truncated' moments, or integrals of structure functions over restricted regions of x, to determine the degree to which individual resonance regions are dominated by leading twist. Because truncated moments obey the same Q{sup 2} evolution equations as the leading twist parton distributions, this approach makes possible for the first time a description of resonance region data and the phenomenon of quark-hadron duality directly from QCD.
Comment on {open_quotes}Covariant duality symmetric actions{close_quotes}
Pasti, P.; Sorokin, D.; Tonin, M.
1997-08-01
We demonstrate that an action proposed by Khoudeir and Pantoja [Phys. Rev. D {bold 53}, 5974 (1996)] for endowing Maxwell theory with manifest electric-magnetic duality symmetry contains, in addition to the Maxwell field, additional propagating vector degrees of freedom. Hence it cannot be considered as a duality symmetric action for a {ital single} Abelian gauge field. {copyright} {ital 1997} {ital The American Physical Society}
Tripathy, Arun Kumar
2014-01-01
Three approaches of second order mixed type duality are introduced for a nondifferentiable multiobjective fractional programming problem in which the numerator and denominator of objective function contain square root of positive semidefinite quadratic form. Also, the necessary and sufficient conditions of efficient solution for fractional programming are established and a parameterization technique is used to establish duality results under generalized second order ρ-univexity assumption. PMID:27379308
Challenges in assessing college students' conception of duality: the case of infinity
NASA Astrophysics Data System (ADS)
Babarinsa-Ochiedike, Grace Olutayo
Interpreting students' views of infinity posits a challenge for researchers due to the dynamic nature of the conception. There is diversity and variation among students' process-object perceptions. The fluctuations between students' views however reveal an undeveloped duality conception. This study examined college students' conception of duality in understanding and representing infinity with the intent to design strategies that could guide researchers in categorizing students' views of infinity into different levels. Data for the study were collected from N=238 college students enrolled in Calculus sequence courses (Pre-Calculus, Calculus I through Calculus III) at one of the southwestern universities in the U.S. using self-report questionnaires and semi-structured individual task-based interviews. Data was triangulated using multiple measures analyzed by three independent experts using self-designed coding sheets to assess students' externalization of the duality conception of infinity. Results of this study reveal that college students' experiences in traditional Calculus sequence courses are not supportive of the development of duality conception. On the contrary, it strengthens the singularity perspective on fundamental ideas of mathematics such as infinity. The study also found that coding and assessing college students' conception of duality is a challenging and complex process due to the dynamic nature of the conception that is task-dependent and context-dependent. Practical significance of the study is that it helps to recognize misconceptions and starts addressing them so students will have a more comprehensive view of fundamental mathematical ideas as they progress through the Calculus coursework sequence. The developed duality concept development framework called Action-Process-Object-Duality (APOD) adapted from the APOS theory could guide educators and researchers as they engage in assessing students' conception of duality. The results of this study
Duality relation and joint measurement in a Mach-Zehnder interferometer
Liu Naile; Li Li; Chen Zengbing; Yu Sixia
2009-05-15
The Mach-Zehnder interferometric setup quantitatively characterizing the wave-particle duality implements in fact a joint measurement of two unsharp observables. We present a necessary and sufficient condition for such a pair of unsharp observables to be jointly measurable. The condition is shown to be equivalent to a duality inequality, which for the optimal strategy of extracting the which-path information is more stringent than the Jaeger-Shimony-Vaidman-Englert inequality.
The politics of researching global health politics
Rushton, Simon
2015-01-01
In this comment, I build on Shiffman’s call for the global health community to more deeply investigate structural and productive power. I highlight two challenges we must grapple with as social scientists carrying out the types of investigation that Shiffman proposes: the politics of challenging the powerful; and the need to investigate types of expertise that have traditionally been thought of as ‘outside’ global health. In doing so, I argue that moving forward with the agenda Shiffman sets out requires social scientists interested in the global politics of health to be reflexive about our own exercise of structural and productive power and the fact that researching global health politics is itself a political undertaking. PMID:25905482
Political Information Content and Children's Political Socialization.
ERIC Educational Resources Information Center
Sandell, Karin L.; Ostroff, David H.
1981-01-01
A content analysis of television programs presented during times likely to have high proportions of children in the audience indicated that entertainment programs contain messages about the political system which are often negative or inaccurate. (Author/MER)