strings@ar

XXXI Encuentro de la red strings@ar.
Martes 12 de agosto de 2008, DF-UNLP

PROGRAMA

XXXI Encuentro de la red strings@ar - Programa (póster para imprimir)

	Martes 12 de agosto de 2008 DF-UNLP, La Plata
09h50 - 10h00	Apertura
10h00 - 11h00	Nicolás Grandi (Instituto de Física de La Plata) Compact self-gravitating solutions of K-fields in brane cosmology
11h00 - 11h30	Café
11h30 - 12h30	Fernando Lombardo (Universidad de Buenos Aires) Quantum dissipative effects in moving mirrors: particle creation and decoherence
12h30 - 14h00	Almuerzo
14h00 - 15h00	José Edelstein (Universidad de Santiago de Compostela) Sources for Chern-Simons theories
15h00 - 15h30	Café
16h00 - 17h00	Norberto Scoccola (CNEA & CONICET & Universidad Favaloro) Hadronic and quark matter under extreme conditions of temperature and/or density

Nicolás Grandi (Instituto de Física de La Plata)
Compact self-gravitating solutions of K-fields in brane cosmology
Recently we proposed that K fields, that is, fields with a non-standard kinetic term, may provide a mechanism for the generation of thick branes, based on the following observations. Firstly, K field theories allow for soliton solutions with compact support, i.e., compactons. Compactons in 1+1 dimensions may give rise to topological defects of the domain wall type and with finite thickness in higher dimensions. Secondly, propagation of linear perturbations is confined inside the compacton domain wall. Further, these linear perturbations inside the topological defect are of the standard type, in spite of the non-standard kinetic term. Thirdly, when gravity is taken into account, location of gravity in the sense of Randall--Sundrum works for these compacton domain walls provided that the backreaction of gravity does not destabilize the compacton domain wall. It is the purpose of the present paper to investigate in detail the existence and stability of compacton domain walls in the full K field and gravity system, using both analytical and numerical methods. We find that the existence of the domain wall in the full system requires a correlation between the gravitational constant and the bulk cosmological constant, which is thoroughly analyzed.

Fernando Lombardo (Universidad de Buenos Aires)
Quantum dissipative effects in moving mirrors: particle creation and decoherence
We use a functional approach to study various aspects of the quantum effective dynamics of moving, planar, dispersive mirrors, coupled to scalar or Dirac fields. We first compute the Euclidean effective action, and use it to derive the imaginary part of the 'in-out' effective action. We also obtain, for the case of the real scalar field in 1 + 1 dimensions, the Schwinger-Keldysh effective action and a semiclassical Langevin equation that describes the motion of the mirror including noise and dissipative effects due to its coupling to the quantum fields.

José Edelstein (Universidad de Santiago de Compostela)
Sources for Chern-Simons theories
The coupling between Chern-Simons theories and matter sources defined by branes of different dimensionalities is examined. It is shown that the standard coupling to membranes, such as the one found in supergravity or in string theory, does not operate in the same way for CS theories; the only p-branes that naturally couple seem to be those with p=2n; these p-branes break the gauge symmetry (and supersymmetry) in a controlled and sensible manner.

Norberto Scoccola (CNEA & CONICET & Universidad Favaloro)
Hadronic and quark matter under extreme conditions of temperature and/or density
El comportamiento de la materia hadrónica y de quarks en condiciones extremas de temperatura y/o densidad se ha transformado en una de las cuestiones más importantes de la física de las interacciones fuertes. Un conocimiento detallado del correspondiente diagrama de fases es de gran importancia para entender fenómenos relacionados con, por ejemplo, el Universo temprano, el interior de las estrellas de neutrones y las colisiones entre iones pesados relativistas. En esta presentación se expondrán algunos aspectos de los avances logrados en la descripción de este tipo de materia utilizando modelos efectivos de QCD.