Gravitational collapse, shear-free anisotropic radiating star

TL;DR

This paper derives exact solutions for shear-free, anisotropic radiating stars undergoing gravitational collapse, matching interior metrics with exterior Vaidya spacetime, and analyzes their thermodynamic and observational properties during collapse.

Contribution

It introduces a new class of exact Einstein solutions for shear-free anisotropic radiating stars that evolve from static configurations to black hole horizons.

Findings

Interior solutions satisfy physical and thermodynamic conditions.

Luminosity and temperature are zero at the start and horizon formation.

Solutions describe a realistic collapse process leading to black hole formation.

Abstract

We present a class of exact solutions of Einstein field equations for a shear-free spherically symmetric anisotropic fluid undergoing radial heat flow. The interior metric fulfilled all the relevant physical and thermodynamic conditions and matched with Vaidya exterior metric over the boundary. Initially the interior solutions represent a static configuration of dissipative fluid which then gradually starts evolving into radiating collapse. The apparent luminosity observed by the distant observer at rest at infinity and the effective surface temperature are zero in remote past at the instance when collapse begins and at the stage when collapsing configuration reach the horizon of the black hole.