1,378 research outputs found
Perturbative Computation of Glueball Superpotentials
Using N=1 superspace techniques in four dimensions we show how to
perturbatively compute the superpotential generated for the glueball superfield
upon integrating out massive charged fields. The technique applies to arbitrary
gauge groups and representations. Moreover we show that for U(N) gauge theories
admitting a large N expansion the computation dramatically simplifies and we
prove the validity of the recently proposed recipe for computation of this
quantity in terms of planar diagrams of matrix integrals.Comment: 15 Pages, 2 Figure
On the Matter of the Dijkgraaf--Vafa Conjecture
With the aim of extending the gauge theory -- matrix model connection to more
general matter representations, we prove that for various two-index tensors of
the classical gauge groups, the perturbative contributions to the glueball
superpotential reduce to matrix integrals. Contributing diagrams consist of
certain combinations of spheres, disks, and projective planes, which we
evaluate to four and five loop order. In the case of with antisymmetric
matter, independent results are obtained by computing the nonperturbative
superpotential for and 8. Comparison with the Dijkgraaf-Vafa approach
reveals agreement up to loops in matrix model perturbation theory, with
disagreement setting in at loops, being the dual Coxeter number.
At this order, the glueball superfield begins to obey nontrivial relations
due to its underlying structure as a product of fermionic superfields. We
therefore find a relatively simple example of an gauge theory
admitting a large expansion, whose dynamically generated superpotential
differs from the one obtained in the matrix model approach.Comment: 20 pages, harvmac. v2: added comments and reference
Planar Gravitational Corrections For Supersymmetric Gauge Theories
In this paper we discuss the contribution of planar diagrams to gravitational
F-terms for N=1 supersymmetric gauge theories admitting a large N description.
We show how the planar diagrams lead to a universal contribution at the
extremum of the glueball superpotential, leaving only the genus one
contributions, as was previously conjectured. We also discuss the physical
meaning of gravitational F-terms.Comment: 20 pages, 4 figure
Constructing Gauge Theory Geometries from Matrix Models
We use the matrix model -- gauge theory correspondence of Dijkgraaf and Vafa
in order to construct the geometry encoding the exact gaugino condensate
superpotential for the N=1 U(N) gauge theory with adjoint and symmetric or
anti-symmetric matter, broken by a tree level superpotential to a product
subgroup involving U(N_i) and SO(N_i) or Sp(N_i/2) factors. The relevant
geometry is encoded by a non-hyperelliptic Riemann surface, which we extract
from the exact loop equations. We also show that O(1/N) corrections can be
extracted from a logarithmic deformation of this surface. The loop equations
contain explicitly subleading terms of order 1/N, which encode information of
string theory on an orientifolded local quiver geometry.Comment: 52 page
Geometric transitions and integrable systems
We consider {\bf B}-model large duality for a new class of noncompact
Calabi-Yau spaces modeled on the neighborhood of a ruled surface in a
Calabi-Yau threefold. The closed string side of the transition is governed at
genus zero by an Hitchin integrable system on a genus Riemann surface
. The open string side is described by a holomorphic Chern-Simons
theory which reduces to a generalized matrix model in which the eigenvalues lie
on the compact Riemann surface . We show that the large planar
limit of the generalized matrix model is governed by the same Hitchin
system therefore proving genus zero large duality for this class of
transitions.Comment: 70 pages, 1 figure; version two: minor change
A Farey Tail for Attractor Black Holes
The microstates of 4d BPS black holes in IIA string theory compactified on a
Calabi-Yau manifold are counted by a (generalized) elliptic genus of a (0,4)
conformal field theory. By exploiting a spectral flow that relates states with
different charges, and using the Rademacher formula, we find that the elliptic
genus has an exact asymptotic expansion in terms of semi-classical
saddle-points of the dual supergravity theory. This generalizes the known
"Black Hole Farey Tail" of [1] to the case of attractor black holes.Comment: 36 pages, 3 figures, note adde
On Effective Superpotentials and Compactification to Three Dimensions
We study four dimensional N=2 SO/SP supersymmetric gauge theory on R^3\times
S^1 deformed by a tree level superpotential. We will show that the exact
superpotential can be obtained by making use of the Lax matrix of the
corresponding integrable model which is the periodic Toda lattice. The
connection between vacua of SO(2N) and SO(2kN-2k+2) can also be seen in this
framework. Similar analysis can also be applied for SO(2N+1) and SP(2N).Comment: 18 pages, latex file, v2: typos corrected, refs adde
Topological Phase Transitions and Holonomies in the Dimer Model
We demonstrate that the classical dimer model defined on a toroidal hexagonal
lattice acquires holonomy phases in the thermodynamic limit. When all
activities are equal the lattice sizes must be considered mod 6 in which case
the finite size corrections to the bulk partition function correspond to a
massless Dirac Fermion in the presence of a flat connection with nontrivial
holonomy. For general bond activities we find that the phase transition in this
model is a topological one, where the torus degenerates and its modular
parameter becomes real at the critical temperature. We argue that these
features are generic to bipartite dimer models and we present a more general
lattice whose continuum partition function is that of a massive Dirac Fermion.Comment: 7 pages, 4 figures. Minor corrections with additional figure
Combinatorial Identities and Quantum State Densities of Supersymmetric Sigma Models on N-Folds
There is a remarkable connection between the number of quantum states of
conformal theories and the sequence of dimensions of Lie algebras. In this
paper, we explore this connection by computing the asymptotic expansion of the
elliptic genus and the microscopic entropy of black holes associated with
(supersymmetric) sigma models. The new features of these results are the
appearance of correct prefactors in the state density expansion and in the
coefficient of the logarithmic correction to the entropy.Comment: 8 pages, no figures. To appear in the European Physical Journal
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