strings@ar

XXXVI Encuentro de la red strings@ar.
Viernes 24 de abril de 2009, IAFE

PROGRAMA

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

	Viernes 24 de abril de 2009 IAFE, Ciudad Universitaria, Buenos Aires
11h20 - 11h30	Apertura
11h30 - 12h30	Ezequiel Álvarez (Univ. de Buenos Aires) Featuring the Lee-Wick Standard Model
12h30 - 14h00	Almuerzo
14h00 - 15h00	Franco Fiorini (IAFE, Buenos Aires) A type of regular Born-Infeld gravity
15h00 - 15h15	Café
15h15 - 16h15	Hideki Maeda (CECS, Valdivia) Dynamical black holes with symmetry in Einstein-Gauss-Bonnet gravity
16h15 - 16h30	Café
16h30 - 17h30	Gerardo Aldazábal (Instituto Balseiro) Fluxes and string compactifications

Ezequiel Álvarez (Univ. de Buenos Aires)
Featuring the Lee-Wick Standard Model
El Lee-Wick Standard Model (LWSM) es un modelo del 2007 que soluciona el problema de la jerarquía a costo de introducir partículas nuevas con signos inusuales en los terminos cinéticos. Voy a presentar el modelo y contar dos tabajos realizados al respecto. El primero trata de realizarle los ElectroWeak Precision Tests (EWPT) al modelo para acotar su espacio de parámetros; y el segundo trata de buscar observables de acausalidad característicos del LWSM que puedan ser observados en el LHC.

Franco Fiorini (IAFE, Buenos Aires)
A type of regular Born-Infeld gravity
Born-Infeld deformation strategy to smooth theories having divergent solutions is applied to the teleparallel equivalent of General Relativity. The equivalence between teleparallelism and General Relativity is exploited to obtain a deformed theory of gravity based on second order differential equations, since teleparallel Lagrangian is built just from first derivatives of the vierbein. We show that Born-Infeld teleparallelism cures the initial singularity in a spatially flat FRW universe; moreover, it provides a natural inflationary stage without resorting to an inflaton field. The Born-Infeld parameter λ bounds the dynamics of Hubble parameter H(t) and establishes a maximum attainable spacetime curvature. We conclude the talk discussing certain preliminary results concerning three dimensional black holes in vacuum.

Hideki Maeda (CECS, Valdivia)
Dynamical black holes with symmetry in Einstein-Gauss-Bonnet gravity
We explore various aspects of dynamical black holes defined by a future outer trapping horizon in n(≥ 5)-dimensional Einstein-Gauss-Bonnet gravity. We assume that the spacetime has symmetries corresponding to the isometries of an (n-2)-dimensional maximally symmetric space and the Gauss-Bonnet coupling constant is non-negative. Depending on the existence or absence of the general relativistic limit, solutions are classified into GR and non-GR branches, respectively. Assuming the null energy condition on matter fields, we show that a future outer trapping horizon in the GR branch possesses the same properties as that in general relativity. In contrast, that in the non-GR branch is shown to be non-spacelike with its area non-increasing into the future. We can recognize this peculiar behavior to arise from a fact that the null energy condition necessarily leads to the null convergence condition for radial null vectors in the GR branch, but not in the non-GR branch. The energy balance law yields the first law of a trapping horizon, from which we can read off the entropy of a trapping horizon reproducing Iyer-Wald's expression. The entropy of a future outer trapping horizon is shown to be non-decreasing in both branches along its generator.