Functional bosonization of a Dirac field in 2 + 1 dimensions, in the presence of a boundary

We apply the functional bosonization procedure to a massive Dirac field defined on a 2+1 dimensional spacetime which has a non-trivial boundary. We find the form of the bosonized current both for the bulk and boundary modes, showing that the gauge field in the bosonized theory contains a perfect-conductor boundary condition on the worldsheet spanned by the boundary. We find the bosonized action for the corresponding boundary modes.Fil: Fosco, Cesar Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Comisión Nacional de Energía Atómica. Centro Atómico Bariloche; ArgentinaFil: Schaposnik, Fidel Arturo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Física La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de Física La Plata; Argentin

Explicit R-symmetry breaking and metastable vacua

We consider O'Raifeartaigh-like models with explicit R-symmetry breaking and analyze the vacuum landscape. Taking such models as candidates for the hidden sector, we analyze the gauge mediation of the supersymmetry breaking, focusing on the effects produced by R-symmetry breaking. First, we construct families of non-R-symmetric models containing only singlet chiral superfields, and determine the conditions under which SUSY vacua, runaway directions and (longlived) metastable vacua exist. We then extend the results to the case in which some of the chiral fields are in the 5⊕5 representation of SU(5). Gauging this symmetry, we compute soft masses for gauginos and sfermions, and analyze several issues such as doublet/triplet splitting, unification of coupling constants and CP violation phases.Facultad de Ciencias Exacta

Vortex solutions of an Abelian Higgs model with visible and hidden sectors

We study vortex solutions in a theory with dynamics governed by two weakly coupled Abelian Higgs models, describing a hidden sector and a visible sector. We analyze the radial dependence of the axially symmetric solutions constructed numerically and discuss the stability of vortex configurations for different values of the model parameters, studying in detail vortex decay into lower energy configurations. We find that even in a weak coupling regime vortex solutions strongly depend on the parameters of both the visible and hidden sectors. We also discuss on qualitative grounds possible implications of the existence of a hidden sector in connection with superconductivity and dark matter (dark strings).Facultad de Ciencias Exacta

Lifshitz holography with a probe Yang-Mills field

Taking as a probe an SU(2) gauge field with Yang-Mills action in a 3 + 1 dimensional Lifshitz black hole background, we use the gauge/gravity correspondence to discuss finite temperature effects in the dual theory defined on the boundary. In order to test the dependence of results on the anisotropic scaling exponent z we consider two analytical black hole solutions with z=2 and z=4. Apart from solving the equations of motion in the bulk using a numerical approach, we also apply an analytical approximation allowing the determination of the phase transition character, the critical exponent and the critical temperature behavior as a function of z.Facultad de Ciencias ExactasInstituto de Física La Plat

La historia clínica en medicina interna : Pasado y presente

La Historia, ontológicamente considerada, es un ente móvil, con una velocidad de aceleración creciente, es decir, con una acumulación cada vez más rápida de cambios significativos sociales, culturales, políticos y científicos. Si extendemos a la Medicina la analogía que estableció el filósofo argentino García Venturini entre la Historia y la teoría general de la relatividad de Einstein, podemos afirmar que la Medicina, en su continuo movimiento de progreso, está sometida a un registro de aceleración creciente, a la vez que aumenta la masa de sus conocimientos y la energía cinética, vale decir, la implicación universal, la fuerza expansiva de cada nuevo descubrimiento. De la misma manera, la historia clínica ha experimentado profundas modificaciones en su concepto y contenido específico, acompasadamente con las corrientes médicas de cada época.Facultad de Ciencias Médica

Explicit R-symmetry breaking and metastable vacua

We consider O'Raifeartaigh-like models with explicit R-symmetry breaking and analyze the vacuum landscape. Taking such models as candidates for the hidden sector, we analyze the gauge mediation of the supersymmetry breaking, focusing on the effects produced by R-symmetry breaking. First, we construct families of non-R-symmetric models containing only singlet chiral superfields, and determine the conditions under which SUSY vacua, runaway directions and (longlived) metastable vacua exist. We then extend the results to the case in which some of the chiral fields are in the 5⊕5 representation of SU(5). Gauging this symmetry, we compute soft masses for gauginos and sfermions, and analyze several issues such as doublet/triplet splitting, unification of coupling constants and CP violation phases.Facultad de Ciencias Exacta

A comment on bosonization in d ≥ 2 dimensions

We discuss recent results on bosonization in d ≥ 2 space-time dimensions by giving a very simple derivation for the bosonic representation of the original free fermionic model both in the abelian and non-abelian cases. We carefully analyse the issue of symmetries in the resulting bosonic model as well as the recipes for bosonization of fermion currents.Facultad de Ciencias ExactasComisión de Investigaciones Científicas de la provincia de Buenos Aire

Noncommutative solitons and instantons

I review different approaches to the construction of vortex and instanton solutions in noncommutative field theories.Facultad de Ciencias Exacta

Quantum mechanics in non(anti)commutative superspace

We consider non(anti)commutative (NAC) deformations of d ≤ 1 ≤ 2 superspace. We find that, in the chiral base, the deformation preserves only a half of the original (linearly realized) supercharge algebra, as it usually happens in NAC field theories. We obtain in terms of a real supermultiplet a closed expression for a deformed Quantum Mechanics Lagrangian in which the original superpotential is smeared, similarly to what happens for the two dimensional deformed sigma model. Quite unexpectedly, we find that a second conserved charge can be constructed which leads to a nonlinear field realization of the supersymmetry algebra, so that finally the deformed theory has as many conserved supercharges as the undeformed one. The quantum behavior of these supercharges is analyzed.Facultad de Ciencias Exacta

Vortices in fracton type gauge theories

We consider a vector gauge theory in 2+1 dimensions of the type recently proposed by Radzihovsky and Hermele [1] to describe fracton phases of matter. The theory has U(1)×U(1) vector gauge fields coupled to an additional vector field with a non conventional gauge symmetry. We added to the theory scalar matter in order to break the gauge symmetry. We analyze non trivial configurations by reducing the field equations to first order self dual (BPS) equations which we solved numerically. We have found vortex solutions for the gauge fields which in turn generate for the extra vector field non-trivial configurations that can be associated to magnetic dipoles.Fil: Lozano, Gustavo Sergio. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Física de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Física de Buenos Aires; ArgentinaFil: Schaposnik, Fidel Arturo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Física La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de Física La Plata; Argentin