ON THE MOTION OF A TEST PARTICLE AROUND A GLOBAL MONOPOLE IN A MODIFIED GRAVITY

In this paper we suggest an approach to analyze the motion of a test particle in the spacetime of a global monopole within a f(R)-like modified gravity. The field equations are written in a simplified form in terms of F (R) = df(R)/dR. Since we are dealing with a spherically symmetric metric, we express F(R) as a function of the radial coordinate only, e.g., F(r) = F (R(r)). So, the choice of a specific form for f(R) will be equivalent to adopt an Ansatz for F(r). By choosing an explicit functional form for F(r), we obtain the weak field solutions for the metric tensor also compute the time-like geodesics and analyze the motion of a massive test particle. An interesting feature is an emerging attractive force exerted by the monopole on the particle.