Cylindrical Collapse and Gravitational Waves

TL;DR

This paper investigates the matching conditions in anisotropic cylindrical gravitational collapse, revealing that radial pressure on the surface is non-zero and proportional to the time-dependent gravitational field, akin to radiation effects in spherical collapse.

Contribution

It provides a detailed analysis of the surface pressure behavior in anisotropic cylindrical collapse, highlighting its proportionality to the collapsing fluid's gravitational field.

Findings

Radial pressure is non-zero on the cylinder surface.

Radial pressure is proportional to the time-dependent gravitational field.

Resembles radiation effects in spherical collapsing fluids.

Abstract

We study the matching conditions for a collapsing anisotropic cylindrical perfect fluid, and we show that its radial pressure is non zero on the surface of the cylinder and proportional to the time dependent part of the field produced by the collapsing fluid. This result resembles the one that arises for the radiation - though non-gravitational - in the spherically symmetric collapsing dissipative fluid, in the diffusion approximation.