Separating expansion and collapse in general fluid models with heat flux

Morgan Le Delliou (1, 2) , José Pedro Mimoso (2, 3) , Filipe C. Mena (4, 5) , Michele Fontanini (1) , Daniel C. Guariento (1) , Elcio Abdalla (1)

1 DFMA/IF-USP - Departamento de Física-Matemática, Instituto de Física da USP
2 CAAUL - Centro de Astronomia e Astrofísica da Universidade de Lisboa
3 DFUL - Departamento de Fı́sica, Faculdade de Ciências [University of Lisbon]
4 CMAT - Centro de Matemática [Minho]
5 DFT-IF-UERJ - Departamento de Fisica Teórica, Instituto de Física, Universidade do Estado do Rio de Janeiro

In this letter we consider spherically symmetric general fluids with heat flux and give the appropriate set of conditions that define the divide between expansion and collapse in the cases in which heat flux and its evolution vanish at the separating surface. We extend previous works with a fully non-linear analysis in the $3 + 1$ splitting, and present gauge-invariant results. The definition of the separating surface is inspired by the conservation of the Misner-Sharp mass, and is obtained by generalizing the Tolman-Oppenheimer-Volkoff equilibrium and turnaround conditions. We emphasize the non-local character of these conditions as found in previous works and discuss connections to the phenomena of spacetime cracking and thermal peeling.

Domaines: Relativité Générale et Cosmologie Quantique [gr-qc]; Cosmologie et astrophysique extra-galactique [astro-ph.CO]; Cosmologie et astrophysique extra-galactique [astro-ph.CO]; Physique des Hautes Energies - Théorie [hep-th]

Morgan Le Delliou, José Pedro Mimoso, Filipe C. Mena, Michele Fontanini, Daniel C. Guariento, et al.. Separating expansion and collapse in general fluid models with heat flux. 2013. ⟨hal-00822567⟩