Gravitational collapse inf(R) theories

Abstract

We study the gravitational collapse in modified gravitational theories. In particular, we analyze a general f (R) model with uniformly collapsing cloud of self-gravitating dust particles. This analysis shares analogies with the formation of large-scale structures in the early Universe and with the formation of stars in a molecular cloud experiencing gravitational collapse. In the same way, this investigation can be used as a first approximation to the modification that stellar objects can suffer in these modified theories of gravity. We study concrete examples, and find that the analysis of gravitational collapse is an important tool to constrain models that present late-time cosmological acceleration.

Influence of modification of gravity on the dynamics of radiating spherical fluids

“…Starobinsky [15] suggested that quadratic Ricci scalar corrections, i.e., f (R) = R + αR 2 in the field equations could be helpful to cause exponential early universe expansion. Several relativisticts [46] adopted this formulation not only for an inflationary constitute but also as a substitute for dark matter (DM) for α = [48]. This is the minimum value of M which follows from Cavendish-type laboratory tests of the Newton law of gravity.…”

Gravitational Dust Collapse in f (R) Gravity

“…Spherically symmetric perfect fluid gravitational collapse has been discussed in metric f (R) gravity by Sharif and Kausar [39]. Cembranos et al [40] analyzed a general f (R) model with uniformly collapsing cloud of self-gravitating dust particles.…”

Influence of $$f\,(R)$$ f ( R ) models on the existence of anisotropic self-gravitating systems

“…Cembranos et al [64] examined GC of non-static inhomogeneous gravitational sources and studied the large-scale structure formation for an early-time cosmos in different f (R) gravity theories. Modified gravity theories are likely to host massive celestial objects with smaller radii as compared to GR [65][66][67][68][69][70].…”