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Simple Stringy Dynamical SUSY Breaking

Description: We present simple string models which dynamically break supersymmetry without non-Abelian gauge dynamics. The Fayet model, the Polonyi model, and the O'Raifeartaigh model each arise from D-branes at a specific type of singularity. D-brane instanton effects generate the requisite exponentially small scale of supersymmetry breaking.
Date: August 8, 2007
Creator: Aharony, Ofer; /Weizmann Inst. /Stanford U., Phys. Dept. /SLAC; Kachru, Shamit; Silverstein, Eva & /Stanford U., Phys. Dept. /SLAC
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On Yang--Mills Theories with Chiral Matter at Strong Coupling

Description: Strong coupling dynamics of Yang-Mills theories with chiral fermion content remained largely elusive despite much effort over the years. In this work, we propose a dynamical framework in which we can address non-perturbative properties of chiral, non-supersymmetric gauge theories, in particular, chiral quiver theories on S{sub 1} x R{sub 3}. Double-trace deformations are used to stabilize the center-symmetric vacuum. This allows one to smoothly connect smaller(S{sub 1}) to larger(S{sub 1}) phys… more
Date: August 20, 2008
Creator: Shifman, M.; /Minnesota U., Theor. Phys. Inst. /Saclay, SPhT; Unsal, Mithat & /SLAC /Stanford U., Phys. Dept.
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Unitarity Constraints on Asymmetric Freeze-In

Description: This paper considers unitarity and CPT constraints on asymmetric freeze-in, the use of freeze-in to store baryon number in a dark sector. In this scenario, Sakharov's out of equilibrium condition is satisfied by placing the visible and hidden sectors at different temperatures while a net visible baryon number is produced by storing negative baryon number in a dark sector. It is shown that unitarity and CPT lead to unexpected cancellations. In particular, the transfer of baryon number cancels co… more
Date: August 15, 2011
Creator: Hook, Anson
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Deconfinement in Yang-Mills Theory through Toroidal Compactification

Description: We introduce field theory techniques through which the deconfinement transition of four-dimensional Yang-Mills theory can be moved to a semi-classical domain where it becomes calculable using two-dimensional field theory. We achieve this through a double-trace deformation of toroidally compactified Yang-Mills theory on R{sup 2} x S{sub L}{sup 1} x S{sub {beta}}{sup 1}. At large N, fixed-L, and arbitrary {beta}, the thermodynamics of the deformed theory is equivalent to that of ordinary Yang-Mil… more
Date: August 12, 2011
Creator: Simic, Dusan; Unsal, Mithat & /Stanford U., Phys. Dept. /SLAC
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New Dualities in Supersymmetric Chiral Gauge Theories

Description: We analyze the phase structure of supersymmetric chiral gauge theories with gauge group SU(N), an antisymmetric, and F {le} N + 3 flavors, in the presence of a cubic superpotential. When F = N + 3 the theory flows to a superconformal fixed point in the infrared, and new dual descriptions of this theory are uncovered. The theory with odd N admits a self-dual magnetic description. For general N, we find an infinite family of magnetic dual descriptions, characterized by arbitrarily large gauge gro… more
Date: August 15, 2011
Creator: Craig, Nathaniel; /Princeton, Inst. Advanced Study /Rutgers U., Piscataway; Essig, Rouven; Hook, Anson; Torroba, Gonzalo & /Stanford U., Phys. Dept. /SLAC
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2d Affine XY-Spin Model/4d Gauge Theory Duality and Deconfinement

Description: We introduce a duality between two-dimensional XY-spin models with symmetry-breaking perturbations and certain four-dimensional SU(2) and SU(2) = Z{sub 2} gauge theories, compactified on a small spatial circle R{sup 1,2} x S{sup 1}, and considered at temperatures near the deconfinement transition. In a Euclidean set up, the theory is defined on R{sup 2} x T{sup 2}. Similarly, thermal gauge theories of higher rank are dual to new families of 'affine' XY-spin models with perturbations. For rank t… more
Date: August 16, 2012
Creator: Anber, Mohamed M.; Poppitz, Erich; U., /Toronto; Unsal, Mithat & /SLAC /Stanford U., Phys. Dept. /San Francisco State U.
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The Simplicity of Perfect Atoms: Degeneracies in Supersymmetric Hydrogen

Description: Supersymmetric QED hydrogen-like bound states are remarkably similar to non-supersymmetric hydrogen, including an accidental degeneracy of the fine structure and which is broken by the Lamb shift. This article classifies the states, calculates the leading order spectrum, and illustrates the results in several limits. The relation to other non-relativistic bound states is explored. Supersymmetric bound states provide a laboratory for studying dynamics in supersymmetric theories. Bound states lik… more
Date: August 19, 2011
Creator: Rube, Tomas; /Stanford U., ITP; Wacker, Jay G. & /SLAC /Stanford U., ITP
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Towards a Holographic Marginal Fermi Liquid

Description: We present an infinite class of 2+1 dimensional field theories which, after coupling to semi-holographic fermions, exhibit strange metallic behavior in a suitable large N limit. These theories describe lattices of hypermultiplet defects interacting with parity-preserving supersymmetric Chern-Simons theories with U(N) x U(N) gauge groups at levels {+-}k. They have dual gravitational descriptions in terms of lattices of probe M2 branes in AdS{sub 4} x S{sup 7}/Z{sub k} (for N >> 1,N >&gt… more
Date: August 15, 2011
Creator: Jensen, Kristan; Kachru, Shamit; Karch, Andreas; Polchinski, Joseph & Silverstein, Eva
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What is Science?

Description: Helen Quinn is a theoretical particle physicist at SLAC. Throughout her career, she has been passionately involved in science education and public understanding of science. In talking about science, whether to the public or to students, we scientists often assume that they share with us a common idea of science. In my experience that is often not the case. To oversimplify, scientists think of science both as a process for discovering properties of nature, and as the resulting body of knowledge,… more
Date: August 3, 2009
Creator: Quinn, H
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Adventures in Holographic Dimer Models

Description: We abstract the essential features of holographic dimer models, and develop several new applications of these models. Firstly, semi-holographically coupling free band fermions to holographic dimers, we uncover novel phase transitions between conventional Fermi liquids and non-Fermi liquids, accompanied by a change in the structure of the Fermi surface. Secondly, we make dimer vibrations propagate through the whole crystal by way of double trace deformations, obtaining nontrivial band structure.… more
Date: August 12, 2011
Creator: Kachru, Shamit; /Stanford U., Phys. Dept. /SLAC; Karch, Andreas; /Washington U., Seattle; Yaida, Sho & /Stanford U., Phys. Dept.
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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.; Boucher-Veronneau, C. & Johansson, H.
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Topological Twisted Sigma Model with H-flux Revisited

Description: In this paper we revisit the topological twisted sigma model with H-flux. We explicitly expand and then twist the worldsheet Lagrangian for bi-Hermitian geometry. we show that the resulting action consists of a BRST exact term and pullback terms, which only depend on one of the two generalized complex structures and the B-field. We then discuss the topological feature of the model.
Date: August 18, 2006
Creator: Chuang, Wu-yen
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AdS/CFT and Large-N Volume Independence

Description: We study the Eguchi-Kawai reduction in the strong-coupling domain of gauge theories via the gravity dual of N=4 super-Yang-Mills on R{sup 3} x S{sup 1}. We show that D-branes geometrize volume independence in the center-symmetric vacuum and give supergravity predictions for the range of validity of reduced large-N models at strong coupling.
Date: August 26, 2010
Creator: Poppitz, Erich; U., /Toronto; Unsal, Mithat & /SLAC /Stanford U., Phys. Dept.
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The Complete Four-Loop Four-Point Amplitude in N

Description: We present the complete four-loop four-point amplitude in N = 4 super-Yang-Mills theory, for a general gauge group and general D-dimensional covariant kinematics, and including all non-planar contributions. We use the method of maximal cuts - an efficient application of the unitarity method - to construct the result in terms of 50 four-loop integrals. We give graphical rules, valid in D-dimensions, for obtaining various non-planar contributions from previously-determined terms. We examine the u… more
Date: August 25, 2010
Creator: Bern, Z.; Carrasco, J.J.M.; /UCLA; Dixon, Lance J.; /CERN, /SLAC; Johansson, H. et al.
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Large-N reduction in QCD-like theories with massive adjoint fermions

Description: Large-N QCD with heavy adjoint fermions emulates pure Yang-Mills theory at long distances. We study this theory on a four- and three-torus, and analytically argue the existence of a large-small volume equivalence. For any finite mass, center symmetry unbroken phase exists at sufficiently small volume and this phase can be used to study the large-volume limit through the Eguchi-Kawai equivalence. A finite temperature version of volume independence implies that thermodynamics on R3 x S1 can be st… more
Date: August 26, 2010
Creator: Azeyanagi, Tatsuo; U., /Kyoto; Hanada, Masanori; Inst., /Weizmann; Unsal, Mithat; /Weizmann Inst. /SLAC /Stanford U., Phys. Dept. et al.
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Large-N volume independence in conformal and confining gauge theories

Description: Consequences of large N volume independence are examined in conformal and confining gauge theories. In the large N limit, gauge theories compactified on R{sup d-k} x (S{sup 1}){sup k} are independent of the S{sup 1} radii, provided the theory has unbroken center symmetry. In particular, this implies that a large N gauge theory which, on R{sup d}, flows to an IR fixed point, retains the infinite correlation length and other scale invariant properties of the decompactified theory even when compac… more
Date: August 26, 2010
Creator: Unsal, Mithat & Yaffe, Laurence G.
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Conformality or Confinement (II): One-flavor CFTs and Mixed-Representation QCD

Description: We study QCD-like four dimensional theories in the theoretically controlled framework of deformation theory and/or twisted partition function on S{sup 1} x R{sup 3}. By using duality, we show that a class of one-flavor theories exhibit new physical phenomena: discrete chiral symmetry breaking ({chi}SB) induced by the condensation of topological disorder operators, and confinement and the generation of mass gap due to new non-selfdual topological excitations. In the R{sup 4} limit, we argue that… more
Date: August 26, 2010
Creator: Poppitz, Erich; U., /Toronto; Unsal, Mithat & /SLAC /Stanford U., Phys. Dept.
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'Insightful D-branes'

Description: We study a simple model of a black hole in AdS and obtain a holographic description of the region inside the horizon. A key role is played by the dynamics of the scalar fields in the dual gauge theory. This leads to a proposal for a dual description of D-branes falling through the horizon of any AdS black hole. The proposal uses a field-dependent time reparameterization in the field theory. We relate this reparametrization to various gauge invariances of the theory. Finally, we speculate on inf… more
Date: August 26, 2010
Creator: Horowitz, Gary; /UC, Santa Barbara; Lawrence, Albion; /Brandeis U. /Santa Barbara, KITP; Silverstein, Eva & /SLAC /Stanford U., Phys. Dept. /Santa Barbara, KITP
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Generalized Attractor Points in Gauged Supergravity

Description: The attractor mechanism governs the near-horizon geometry of extremal black holes in ungauged 4D N=2 supergravity theories and in Calabi-Yau compactifications of string theory. In this paper, we study a natural generalization of this mechanism to solutions of arbitrary 4D N=2 gauged supergravities. We define generalized attractor points as solutions of an ansatz which reduces the Einstein, gauge field, and scalar equations of motion to algebraic equations. The simplest generalized attractor geo… more
Date: August 15, 2011
Creator: Kachru, Shamit; /Stanford U., Phys. Dept. /SLAC; Kallosh, Renata; /Stanford U., Phys. Dept.; Shmakova, Marina & /KIPAC, Menlo Park /SLAC /Stanford U., Phys. Dept.
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Stimulated Superconductivity at Strong Coupling

Description: Stimulating a system with time dependent sources can enhance instabilities, thus increasing the critical temperature at which the system transitions to interesting low-temperature phases such as superconductivity or superfluidity. After reviewing this phenomenon in non-equilibrium BCS theory (and its marginal fermi liquid generalization) we analyze the effect in holographic superconductors. We exhibit a simple regime in which the transition temperature increases parametrically as we increase th… more
Date: August 12, 2011
Creator: Bao, Ning; Dong, Xi; Silverstein, Eva; Torroba, Gonzalo & /Stanford U., ITP /Stanford U., Phys. Dept. /SLAC
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