The different kinds of self-similarity in general relativity are discussed, with special emphasis
on similarity of thefirst'kind, corresponding to spacetimes admitting a homothetic vector. We …

The aim of this study is to analyze the role of modification of gravity on some dynamical
properties of spherically symmetric relativistic systems. In this settings, the mathematical …

We examine, in a general manner, the role played by the initial density and velocity
distributions in the gravitational collapse of a spherically symmetric inhomogeneous dust …

An outstanding problem in gravitation theory and relativistic astrophysics today is to
understand the final outcome of an endless gravitational collapse. Such a continual collapse …

We consider Lemaitre-Tolman-Bondi spacetimes from the point of view of a tilted observer,
ie one with respect to which the fluid is radially moving. The imperfect fluid and the …

We obtain covariant expressions that generalize the growing and decaying density modes of
linear perturbation theory of dust sources by means of the exact density perturbation from …

The action for a relativistic free particle of mass m receives a contribution− m R (x, y) from a
path of length R (x, y) connecting the events xi and y i. Using this action in a path integral …

In this study, we investigate the collapsing scenario for the k-essence emergent Vaidya
spacetime in the context of massive gravity's rainbow. For this study, we consider that the …

Generalizing earlier results on the initial data and the final fate of dust collapse, we study
here the relevance of the initial state of a spherically symmetric matter cloud towards …

We study fluid distributions endowed with hyperbolic symmetry, which share many common
features with Lemaitre–Tolman–Bondi (LTB) solutions (eg, they are geodesic, shearing, and …