Gravitational Field of a Global Monopole in a Modified Gravity

TL;DR

This paper investigates the gravitational field of a global monopole within the framework of $f(R)$ gravity, deriving metric components under weak field approximation and comparing results with General Relativity and Brans-Dicke theory.

Contribution

It derives the gravitational field equations for a global monopole in $f(R)$ gravity and provides explicit metric components under weak field approximation.

Findings

Derived metric components for a global monopole in $f(R)$ gravity.

Compared $f(R)$ gravity results with General Relativity and Brans-Dicke theory.

Showed differences and similarities in gravitational fields across theories.

Abstract

In this paper we analyze the gravitational field of a global monopole in the context of $f(R)$ gravity. More precisely, we show that the field equations obtained are expressed in terms of $F(R)=\frac{df(R)}{dR}$. Since we are dealing with a spherically symmetric system, we assume that $F(R)$ is a function of the radial coordinate only. Moreover, adopting the weak field approximation, we can provide all components of the metric tensor. A comparison with the corresponding results obtained in General Relativity and in the Brans-Dicke theory is also made.