Shearing, dissipative collapse influenced by an equation of state

Abstract

We make use of a perturbative scheme to implement an equation of state guided, gravitational collapse of a compact stellar object. General relativity is used in which a spherically symmetric spacetime in Schwarzschild coordinates is assumed with an appropriate energy–momentum tensor allowing for heat-flux. For the dissipative collapse, the Vaidya metric is used for the exterior with the required matching to the interior metric. An initial static configuration is firstly set up and then a linear equation of state is used to assist in closing the system of equations for the perturbative part. The resulting model is physically viable and the effect of shearing stresses are examined in terms of the luminosity. We see that shearing augments the luminosity and duration of the collapse process. Further improvements in the modelling process are believed possible by using more sophisticated gravitational potentials and equations of state.