Pure double layers in quadratic F(R) theories (presentación oral, expositor)

ERNESTO F. EIROA; GRISELDA FIGUEROA AGUIRRE; JOSE M. M. SENOVILLA

Córdoba

Conferencia; Grav19; 2019

FAMAF, Universidad de Córdoba, Argentina

One of the most popular modified gravity theories is obtained by adopting a lagrangian which is a function F(R) of the scalar curvature R. Here we present the construction of spherically symmetric bubbles, by matching a vacuum solution with an exterior one having a non null mass, within the framework of quadratic F(R) theories. Each of these regions have a constant value of the curvature scalar, different from one another, that can be interpreted as different cosmological constants. We use the junction formalism in F(R) for the construction, which in the quadratic case results in a hypersurface that gathers both the characteristics of a thin shell and a gravitational double layer. We show that for a particular set of values of the parameters, it is possible to obtain a pure double layer, so that the surface energy density and the pressure are both null at the shell. This is the first explicit example of a pure double layer in a gravitational theory.