13,597 research outputs found
Universal RG Flows Across Dimensions and Holography
We study RG flows between superconformal field theories living in different
spacetime dimensions which exhibit universal properties, independent of the
details of the UV and IR theories. In particular, when the UV and IR theories
are both even-dimensional we establish exact universal relations between their
conformal anomaly coefficients. We also provide strong evidence for similar
relations between appropriately defined free energies for RG flows between
odd-dimensional theories in the large limit. Holographically, these RG
flows across dimensions are described by asymptotically AdS black branes in a
gauged supergravity theory, which we exhibit explicitly. We also discuss the
uplift of these solutions to string and M-theory and comment on how the entropy
of such black branes is captured by the dual field theory.Comment: 64 pages, 2 figures; v2: additional comments and references, typos
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On gauged linear sigma models with torsion
We study a broad class of two dimensional gauged linear sigma models (GLSMs)
with off-shell N=(2,2) supersymmetry that flow to nonlinear sigma models
(NLSMs) on noncompact geometries with torsion. These models arise from coupling
chiral, twisted chiral, and semichiral multiplets to known as well as to a new
N=(2,2) vector multiplet, the constrained semichiral vector multiplet (CSVM).
We discuss three kinds of models, corresponding to torsionful deformations of
standard GLSMs realizing Kahler, hyperkahler, and Calabi-Yau manifolds. The
(2,2) supersymmetry guarantees that these spaces are generalized Kahler. Our
analysis of the geometric structure is performed at the classical level, but we
also discuss quantum aspects such as R-symmetry anomalies. We provide an
explicit example of a generalized Kahler structure on the conifold.Comment: 39 pages, 1 figure. v2: References adde
Non-toric Cones and Chern-Simons Quivers
We obtain an integral formula for the volume of non-toric tri-Sasaki Einstein
manifolds arising from nonabelian hyperkahler quotients. The derivation is
based on equivariant localization and generalizes existing formulas for Abelian
quotients, which lead to toric manifolds. The formula is particularly valuable
in the context of AdS vacua of M-theory and their field
theory duals. As an application, we consider 3d Chern-Simons
theories with affine ADE quivers. While the series corresponds to
toric , the and series are non-toric. We
compute the volumes of the corresponding seven-manifolds and compare to the
prediction from supersymmetric localization in field theory, finding perfect
agreement. This is the first test of an infinite number of non-toric
AdS/CFT dualities.Comment: 2+24 pages. v2: Minor improvements to the text. Matches published
versio
Kagome lattice antiferromagnets and Dzyaloshinsky-Moriya interactions
We study the consequences of in-plane (D_p) and out-of-plane (D_z)
Dzyaloshinsky-Moriya (DM) interactions on the thermodynamic properties of
spin-1/2} Heisenberg model on the kagome lattice using numerical linked cluster
expansions and exact diagonalization, and contrast them with those of other
perturbations such as exchange anisotropy and dilution. We find that different
combinations of the DM anisotropies lead to a wide variety of thermodynamic
behavior, which are quite distinct from those of most other perturbations. We
argue that the sudden upturn seen experimentally in the susceptibility of the
material ZnCu3(OH)6Cl2 can be understood in terms of Dzyaloshinsky-Moriya
anisotropies with D_p>|D_z|. We also show that the measured specific heat of
the material puts further constraints on the allowed DM parameters.Comment: 12 pages, 15 figures. Content, references, and comments on recent
experiments have been added. Published versio
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