51 research outputs found
Good IR Duals of Bad Quiver Theories
The infrared dynamics of generic 3d N=4 bad theories (as per the
good-bad-ugly classification of Gaiotto and Witten) are poorly understood.
Examples of such theories with a single unitary gauge group and fundamental
flavors have been studied recently, and the low energy effective theory around
some special point in the Coulomb branch was shown to have a description in
terms of a good theory and a certain number of free hypermultiplets. A
classification of possible infrared fixed points for bad theories by Bashkirov,
based on unitarity constraints and superconformal symmetry, suggest a much
richer set of possibilities for the IR behavior, although explicit examples
were not known. In this note, we present a specific example of a bad quiver
gauge theory which admits a good IR description on a sublocus of its Coulomb
branch. The good description, in question, consists of two decoupled quiver
gauge theories with no free hypermultiplets.Comment: 20 pages, 3 figures. Discussion of the Coulomb branch singularities
is further extende
Large-N Solution of the Heterotic Weighted Non-Linear Sigma-Model
We study a heterotic two-dimensional N=(0,2) gauged non-linear sigma-model
whose target space is a weighted complex projective space. We consider the case
with N positively and N^~=N_F - N negatively charged fields. This model is
believed to give a description of the low-energy physics of a non-Abelian
semi-local vortex in a four-dimensional N=2 supersymmetric U(N) gauge theory
with N_F > N matter hypermultiplets. The supersymmetry in the latter theory is
broken down to N=1 by a mass term for the adjoint fields. We solve the model in
the large-N approximation and explore a two-dimensional subset of the mass
parameter space for which a discrete Z_{N-N^~} symmetry is preserved.
Supersymmetry is generically broken, but it is preserved for special values of
the masses where a new branch opens up and the model becomes super-conformal.Comment: 34 pages, 10 figures, references adde
On Three-Dimensional Quiver Gauge Theories of Type B
We study three-dimensional supersymmetric quiver gauge theories with a
non-simply laced global symmetry primarily focusing on framed affine
quiver theories. Using a supersymmetric partition function on a three sphere,
and its transformation under S-duality, we study the three-dimensional ADHM
quiver for instantons with a half-integer Chern-Simons coupling. The
theory after S-duality has no Lagrangian, and can not be represented by a
single quiver, however its partition function can be conveniently described by
a collection of framed affine quivers. This correspondence can be
conjectured to generalize three-dimensional mirror symmetry to theories with
nontrivial Chern-Simons terms. In addition, we propose a formula for the
superconformal index of a theory described by a framed affine quiver.Comment: 39 pages, 7 figure
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