Formation of Cylindrical Gravastars in Modified Gravity

Abstract

In this paper, we analyze a few physical characteristics of gravastar with cylindrical geometry in f (R, T ) theory, where R is the Ricci scalar and T is the trace of energymomentum tensor. The gravastar is generally considered to be a substitute of a black hole with three different regions. In the present work, we examine the formulation of gravastar-like cylindrical structures in f (R, T ) theory. By using Darmois and Israel matching conditions, we formulate a mass function of a thin shell. We calculate the different physical characteristics of gravastar, in particular, entropy within the thin shell, proper length of the intermediate thin shell as well as energy of the shell.

Gravastar configuration in non-conservative Rastall gravity

“…So a number of modified theories have been proposed successively such as f (R), f (T), f (R, T), f (G), f (G, T) and f (R, G) theories etc. A lot of work has been done for the models of gravastar in these theories by many researchers in [41][42][43][44][45]. In 1972, an alternative of GR was proposed by Rastall [46], which recently has captured more attention in the literature due to some beneficial understandings, such as it is stable on gravitational lensing occurrence and deals with entropy and universe age problem in cosmic era.…”