Comments on the String dual to N=1 SQCD

We study the String dual to N=1 SQCD deformed by a quartic superpotential in the quark superfields. We present a unified view of the previous results in the literature and find new exact solutions and new asymptotic solutions. Then we study the Physics encoded in these backgrounds, giving among other things a resolution to an old puzzle related to the beta function and a sufficient criteria for screening. We also extend our results to the SO(Nc) case where we present a candidate for the Wilson loop in the spinorial representation. Various aspects of this line of research are critically analyzed.Comment: 50 pages plus appendixes. Three figures and two table

Supersymmetry and Bosonization in Three Dimensions

We discuss on the possible existence of a supersymmetric invariance in purely fermionic planar systems and its relation to the fermion-boson mapping in three-dimensional quantum field theory. We consider, as a very simple example, the bosonization of free massive fermions and show that, under certain conditions on the masses, this model displays a supersymmetric-like invariance in the low energy regime. We construct the purely fermionic expression for the supercurrent and the non-linear supersymmetry transformation laws. We argue that the supersymmetry is absent in the limit of massless fermions where the bosonized theory is non-local.Comment: 12 pages, LaTeX, no figures, to appear in Physics Letters

D6 branes and M theory geometrical transitions from gauged supergravity

We study the supergravity duals of supersymmetric theories arising in the world-volume of D6 branes wrapping holomorphic two-cycles and special Lagrangian three-cycles within the framework of eight dimensional gauged supergravity. When uplifted to 11d, our solutions represent M-theory on the background of, respectively, the small resolution of the conifold and a manifold with G_2 holonomy. We further discuss on the flop and other possible geometrical transitions and its implications.Comment: 16 pages, harvmac, one figure; references adde

A light scalar from walking solutions in gauge-string duality

We consider the type-IIB background generated by the strong-coupling limit of Nc D5 branes wrapped on S2, and focus our attention on a special class of solutions that exhibit walking behavior. We compute numerically the spectrum of scalar fluctuations around vacua of this class. Besides two cuts, and sequences of single poles converging on one of the branch points, the spectrum contains one isolated scalar, the mass of which is suppressed by the length of the walking region. Approximate scale-invariance symmetry in the walking region suggests that this be interpreted as a light dilaton, the pseudo-Goldstone boson of dilatations.Comment: 4 pages, 3 figures. Superpotential formalism replaced with effective potential. Main results unchange

Walking Dynamics from String Duals

Within the context of a String Theory dual to N=1 gauge theories with gauge group SU(Nc) and large Nc, we identify a class of solutions of the background equations for which a suitably defined dual of the gauge coupling exhibits the features of a walking theory. We find evidence for three distinct, dynamically generated scales, characterizing walking, symmetry breaking and confinement, and we put them in correspondence with field theory by an analysis of the operators driving the flow.Comment: 20 pages, 7 figure

Three-dimensional N=4 N=4 \mathcal{N}=4 linear quivers and non-Abelian T-duals

In this paper we construct a new Type IIB background with an AdS4 factor that preserves =4 Supersymmetry. This solution is obtained using a non-Abelian T-duality transformation on the Type IIA reduction of the AdS4×S7 background. We interpret our configuration as a patch of a more general background with localised sources, dual to the renormalisation fixed point of a Tρ̂ ρ(SU(N)) quiver field theory. This relates explicitly the AdS4 geometry to a D3-D5-NS5 brane intersection, illuminating what seems to be a more general phenomenon, relating AdSp+1 backgrounds generated by non-Abelian T-duality to Dp-D(p+2)-NS5 branes intersections

Massive flows in AdS6/CFT5

We study five-dimensional N=1 Superconformal Field Theories of the linear quiver type. These are deformed by a relevant operator, corresponding to a homogeneous mass term for certain matter fields. The free energy is calculated at arbitrary values of the mass parameter. After a careful regularisation procedure, the result can be put in correspondence with a calculation in the supergravity dual background. The F-theorem is verified for these flows, both in field theory and in supergravity. This letter presents some of the results in the companion paper [1]

The assignment game: core bounds for mixe-pair coalitions

In the assignment game framework, we try to identify those assignment matrices in which no entry can be increased without changing the core of the game. These games will be called buyerseller exact games and satisfy the condition that each mixedpair coalition attains the corresponding matrix entry in the core of the game. For a given assignment game, a unique buyerseller exact assignment game with the same core is proved to exist. In order to identify this matrix and to provide a characterization of those assignment games which are buyerseller exact in terms of the assignment matrix, attainable upper and lower core bounds for the mixedpair coalitions are found. As a consequence, an open question posed in Quint (1991) regarding a canonical representation of a 45olattice by means of the core of an assignment game can now be answered.core, exact games, assignment game