IA/U.Lisboa Seminar - Progresses on expansion/collapse separation: Matter Trapping Surfaces (...) - 28 junho 2016

Instituto de Física Teorica, Universidade Estadual de São Paulo

 

 

Hypersurfaces separating expanding and collapsing regions of cosmological spacetime were previously defined as Matter Trapping Surfaces (MTS). So far spherically symmetric models and perfect to general fluids were discussed. The separating surface conserves the Misner-Sharp mass and combines a generalisation of the Tolman-Oppenheimer-Volkoff equilibrium with turnaround conditions, balancing between the pressure gradients, isotropic and anisotropic, and field strength induced by the inner Misner-Sharp mass and pressure fluxes. Causal thermodynamics motivates heat flux, so extra conditions on its vanishing, together its evolution at the surface, are required. Gauge invariant conditions relate intrinsic spacetime quantities to properties of the matter source and are connected to spacetime cracking and thermal peeling. Connections are finally made with dual null formalism and Trapping Horizons (TH) for perfect fluids.