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F-Theory, T-Duality on K3 Surfaces and N = 2 Supersymmetric Gauge Theories in Four Dimensions

Description: We construct T-duality on K3 surfaces. The T-duality exchanges a 4-brane R-R charge and a O-brane R-R charge. We study the action of the T-duality on the moduli space of O-branes located at points of K3 and 4-branes wrapping it. We apply the construction to F-theory compactified on a Calabi-Yau 4-fold and study the duality of N = 2 SU(N{sub c}) gauge theories in four dimensions. We discuss the generalization to the N = 1 duality scenario.
Date: February 26, 1997
Creator: Hori, K. & Oz, Y.
Partner: UNT Libraries Government Documents Department

Duality after supersymmetry breaking

Description: Starting with two supersymmetric dual theories, we imagine adding a chiral perturbation that breaks supersymmetry dynamically. At low energy we then get two theories with soft supersymmetry-breaking terms that are generated dynamically. With a canonical K{umlt a}hler potential, some of the scalars of the ``magnetic`` theory typically have negative mass-squared, and the vector-like symmetry is broken. Since for large supersymmetry breaking the ``electric`` theory becomes ordinary QCD, the two theories are then incompatible. For small supersymmetry breaking, if duality still holds, the magnetic theory analysis implies specific patterns of chiral symmetry breaking in supersymmetric QCD with small soft masses.
Date: May 1, 1998
Creator: Shadmi, Yael & Cheng, Hsin-Chia
Partner: UNT Libraries Government Documents Department

D-dualized D-brane

Description: We further investigate the dimensional duality (D-duality) proposed in arXiv: 0705.0550 by mainly focusing on the properties of D-branes in this background. We derive the world-sheet correspondence of static D-branes, and discuss the fate of non-static D-branes from the world-sheet viewpoint. The quantum string production with or without D-branes is also studied fromthe time-like Liouville theory. We find that the closed string production from the background is much larger than that from D-branes decaying into nothing.
Date: June 6, 2007
Creator: Nakayama, Yu & Nakayama, Yu
Partner: UNT Libraries Government Documents Department


Description: The authors identify a class of Euclidean configurations which appear to be dominant in the functional integral of the CP{sup N-1} models. These configurations are point-like topological excitations, and they may be viewed as constituents of instantons, although they are defined independently of instantons through a continuum duality transformation. They show not only that these configurations survive as N {yields} {infinity}, but that in the plasma phase they are responsible for the effects encountered within the 1/N expansion - confinement, {theta}-dependence, and dynamical mass generation. They also discuss the possible types of plasma phase for a statistical mechanical model of the interacting excitations. Possible generalization to QCD is briefly discussed.
Date: April 1, 1980
Creator: Bardakci, K.; Caldi, D.G. & Neuberger, H.
Partner: UNT Libraries Government Documents Department

Generalized parameter-free duality models in discrete minmax fractional programming based on second-order optimality conditions

Description: This article discusses the construction of six generalized second-order parameter-free duality models, and proves several weak, strong, and strict converse duality theorems for a discrete minmax fractional programming problem using two partitioning schemes and various types of generalized second-order (ℱ, β, ɸ, 𝜌, θ, 𝑚)-univexity assumptions.
Date: November 8, 2016
Creator: Zalmai, G. J. & Verma, Ram U.
Partner: UNT College of Arts and Sciences

Oppenheimer&Groves : The duality that led to Trinity /.

Description: The alliance of J. Robert Oppenheimer, scientist, and Leslie R. Groves, military leader, is often interpreted as the classic example of the clash between the academic mind and the military style. Evidence suggests, instead, that it was a collaboration that led to the dawn of the nuclear age. Instead of a clash, it was collaboration and an implosion of the diverse talents needed for the success of this project. Discussion of these flawed and fascinating individuals still ignites controversy today. This presentation will explore the backgrounds and personalities of these two men and their work together to accomplish their mission. Was the aftermath inevitable, given a relationship based on respect, but perhaps not trust? The genesis of the modern military-industrial complex rested on the genius of these two men, though they personify two distinct American sub-cultures. What lessons can be drawn from their wartime and post-war relationship? What analogies can be drawn for current American values?
Date: January 1, 2001
Creator: Connaughton, T. G. (Theresa G.) & Smith, S. E. (Sharon E.)
Partner: UNT Libraries Government Documents Department

The origins of quark-hadron duality: How does the square of the sum become the sum of the squares?

Description: Bloom-Gilman duality demonstrates empirically that the electroproduction of N*'s at low momentum transfers averages smoothly around the scaling curve measured at large momentum transfers. The latter is proportional to the sum of the squares of the constituent charges whereas the former involves the coherent excitation of resonances and is driven by the square of summed constituent charges. We determine the minimal necessary conditions for this equality to be realized so that duality can occur and consider the implications for a range of processes that may be studied soon at CEBAF.
Date: January 30, 2001
Creator: Close, Frank E. & Isgur, Nathan
Partner: UNT Libraries Government Documents Department

N = 2 string amplitudes

Description: In physics, solvable models have played very important roles. Understanding a simple model in detail teaches us a lot about more complicated models in generic situations. Five years ago, C. Vafa and I found that the closed N = 2 string theory, that is a string theory with the N = 2 local supersymmetry on the worldsheet, is classically equivalent to the self-dual Einstein gravity in four spacetime dimensions. Thus this string theory is solvable at the classical level. More recently, we have examined the N = 2 string partition function for spacial compactifications, and computed it to all order in the string perturbation expansion. The fact that such computation is possible at all suggests that the N = 2 string theory is solvable even quantum mechanically.
Date: August 1, 1995
Creator: Ooguri, H.
Partner: UNT Libraries Government Documents Department

Quark-Hadron Duality

Description: Quark-hadron duality and its potential applications are discussed. We focus on theoretical efforts to model duality.
Date: March 1, 2002
Creator: Jeschonnek, Sabine & Orden, J.W. Van
Partner: UNT Libraries Government Documents Department

Geometric metastability, quivers and holography

Description: We use large N duality to study brane/anti-brane configurations on a class of Calabi-Yau manifolds. With only branes present, the Calabi-Yau manifolds in question give rise to N=2 ADE quiver theories deformed by superpotential terms. We show that the large N duality conjecture of hep-th/0610249 reproduces correctly the known qualitative features of the brane/anti-brane physics. In the supersymmetric case, the gauge theories have Seiberg dualities which are represented as flops in the geometry. Moreover, the holographic dual geometry encodes the whole RG flow of the gauge theory. In the non-supersymmetric case, the large N duality predicts that the brane/anti-brane theories also enjoy such dualities, and allows one to pick out the good description at a given energy scale.
Date: September 6, 2007
Creator: Aganagic, Mina; Aganagic, Mina; Beem, Christopher & Freivogel, Ben
Partner: UNT Libraries Government Documents Department

Min-max identities on boundaries of convex sets around the origin

Description: Min-max and max-min identities are found for inner products on the boundaries of compact, convex sets whose interiors contain the origin. The identities resemble the minimax theorem but they are different from it. Specifically, the value of each min-max (or max-min) equals the value of a dual problem of the same type. Their solution sets can be characterized geometrically in terms of the enclosed convex sets and their polar sets. However, the solution sets need not be convex nor even connected.
Date: January 31, 2002
Creator: Grcar, Joseph F.
Partner: UNT Libraries Government Documents Department

Unraveling duality violations in hadronic tau decays

Description: 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.
Date: March 3, 2008
Creator: Cata, Oscar; Cata, Oscar; Golterman, Maarten & Peris, Santiago
Partner: UNT Libraries Government Documents Department

Dynamics of Supersymmetric SU(n_c) and USp(2n_c) Gauge Theories

Description: We study dynamical flavor symmetry breaking in the context of a class of N=1 supersymmetric SU(n_c) and USp(2 n_c) gauge theories, constructed from the exactly solvable N=2 theories by perturbing them with small adjoint and generic bare hypermultiplet (quark) masses. We find that the flavor U(n_f) symmetry in SU(n_c) theories is dynamically broken to $U(r)\times U(n_f-r)$ groups for $n_f \leq n_c$. In the r=1 case the dynamical symmetry breaking is caused by the condensation of monopoles in the $\underlinen_f$ representation. For general r, however, the monopoles in the $\underline_n_fC_r$ representation, whose condensation could explain the flavor symmetry breaking but would produce too-many Nambu--Goldstone multiplets, actually"break up'' into"magnetic quarks'' which condense and induce confinement and the symmetry breaking. In USp(2n_c) theories with $n_f\leq n_c + 1$, the flavor SO(2n_f) symmetry is dynamically broken to U(n_f), but with no description in terms of a weakly coupled local field theory. In both SU(n_c) and USp(2 n_c) theories, with larger numbers of quark flavors, besides the vacua with these properties, there exist also vacua with no flavor symmetry breaking.
Date: January 7, 2000
Creator: Carlino, Giuseppe; Konishi, Kenichi & Murayama, Hitoshi
Partner: UNT Libraries Government Documents Department

N >= 4 Supergravity Amplitudes from Gauge Theory at One Loop

Description: We expose simple and practical relations between the integrated four- and five-point one-loop amplitudes of N {ge} 4 supergravity and the corresponding (super-)Yang-Mills amplitudes. The link between the amplitudes is simply understood using the recently uncovered duality between color and kinematics that leads to a double-copy structure for gravity. These examples provide additional direct confirmations of the duality and double-copy properties at loop level for a sample of different theories.
Date: August 19, 2011
Creator: Bern, Z.; /UCLA; Boucher-Veronneau, C.; /SLAC; Johansson, H. & /Saclay
Partner: UNT Libraries Government Documents Department

Soft Contribution to Form Factors of Gamma<sup>*</sup> p -> Delta<sup>+</sup> Transition

Description: The purely nonperturbative soft contribution to the gamma<sup>*</sup> p -> delta<sup>+</sup> transition form factors is estimated using the local quark-hadron duality approach. Our results show that the soft contribution is dominated by the magnetic transition: the ratio G<sup>*</sup> <sub>E</sub> Q<sup>2</sup>/ G<sup>*</sup><sub>M</sub> Q<sup>2</sup> is small for all accessible Q<sup>2</sup>, in contrast to pQCD expectations that G<sup>*</sup><sub>E</sub> (Q<sup>2</sup>) -> -G<sup>*</sup><sub>M</sub> (Q<sup>2</sup>). We also found that the soft contribution to the magnetic form factor is large enough to explain the magnitude of existing experimental data.
Date: September 1, 1995
Creator: Radyushkin, Anatoly & Belyaev, Vladimir
Partner: UNT Libraries Government Documents Department

Quark-Hadron Duality and Intrinsic Transverse Momentum

Description: It is demonstrated in several exclusive processes involving the pion that a local quark-hadron duality prescription is equivalent to using an effective (bar)qq (two-body) light-cone wave function Psi (sup) (LD) (x, k (sub)perpendicular) for the pion. This wave function models soft dynamics of all higher (bar)qG...Gq Fock components of the standard light-cone approach. Contributions corresponding to higher Fock components in a hard regime appear in this approach as radiative corrections and are suppressed by powers of alpha(sub)s / Pi.
Date: November 1, 1995
Creator: Radyushkin, Anatoly
Partner: UNT Libraries Government Documents Department

Fourier Transforms of Functions on a Finite Abelian Group

Description: This paper presents a theory of Fourier transforms of complex-valued functions on a finite abelian group and investigates two applications of this theory. Chapter I is an introduction with remarks on notation. Basic theory, including Pontrvagin duality and the Poisson Summation formula, is the subject of Chapter II. In Chapter III the Fourier transform is viewed as an intertwining operator for certain unitary group representations. The solution of the eigenvalue problem of the Fourier transform of functions on the group Z/n of integers module n leads to a proof of the quadratic reciprocity law in Chapter IV. Chapter V addresses the, use of the Fourier transform in computing.
Date: August 1982
Creator: Currey, Bradley Norton
Partner: UNT Libraries

Quark-Hadron Duality in Inclusive Electron-Nucleus Scattering

Description: Recent inclusive electron-nucleus scattering data have been utilized for precision tests of quark-hadron duality. The data are in the resonance and quasielastic regions and cover a range in Q{sup 2} from 0.5 to 7 (GeV/c){sup 2}. The Q{sup 2} dependence of the moments of the F{sub 2} structure function were investigated and indicate that duality holds for nuclei, even at low Q{sup 2}.
Date: March 1, 2002
Creator: Arrington, J.; Crowder, J.; Ent, R.; Keppel, C. & Niculescu, I.
Partner: UNT Libraries Government Documents Department

Gaugino condensation, loop corrections and S-duality constraint

Description: 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.
Date: November 1, 1996
Creator: Saririan, K.
Partner: UNT Libraries Government Documents Department

Duality in supersymmetric Yang-Mills theory

Description: 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.
Date: February 1, 1997
Creator: Peskin, M.E.
Partner: UNT Libraries Government Documents Department

Flavor decomposition of the nucleon

Description: The author reviews some recent developments in the study of quark flavor distribution in the nucleon, including (1) valence quark distributions and quark-hadron duality prediction for the x {yields} 1 F{sup n}{sub 2}/F{sup p}{sub 2} ration (2) sea quark asymmetries and electromagnetic form factors (3) strange quarks in the nucleon.
Date: June 1, 1999
Creator: Melnitchouk, W.
Partner: UNT Libraries Government Documents Department

Explicit quark-hadron duality in 1+1 dimensions

Description: Explicit quark-hadron duality in the limit of heavy quark mass is studied using the 't Hooft model, where both partonic and hadronic amplitudes may be computed exactly. Results for weak decays of heavy mesons are presented for both standard spectator decays, where the duality limit is convincingly approached, and annihilation decays of the valence quark-antiquark pair, where the approach to asymptotic duality is much less precise.
Date: June 1, 1998
Creator: Lebed, Richard F.
Partner: UNT Libraries Government Documents Department

Pauli Interference in the 't Hooft model: Heavy quark expansion and quark-hadron duality

Description: Pauli Interference in decays of heavy flavor mesons, a genuinely nonleptonic nonperturbative effect, is considered in the 't Hooft model. Analytic summation of the exclusive decay widths yields the same expression as obtained in the OPE-based approach. Threshold-related violations of local duality in PI are found to be suppressed. A novel case is identified where the OPE effect is completely saturated by a single final state.
Date: March 1, 1999
Creator: Bigi, Ikaros & Uraltsev, Nikolai
Partner: UNT Libraries Government Documents Department