As first discovered by Choptuik, the black hole threshold in the space of initial data for
general relativity shows both surprising structure and surprising simplicity. Universality …

In general relativity black holes can be formed from regular initial data that do not contain a
black hole already. The space of regular initial data for general relativity therefore splits …

We study here images of thin accretion disks around black holes and two classes of naked
singularity spacetimes and compare these scenarios. The naked singularity models which …

In this paper, we derive the solutions of orbit equations for a class of naked singularity
spacetimes and compare these with timelike orbits, that is, particle trajectories in the …

We give a model of the higher-dimensional spherically symmetric gravitational collapse of a
dust cloud including the perturbative effects of quantum gravity. The n (≥ 5)-dimensional …

Naked singularities are hypothetical astrophysical objects, characterized by a gravitational
singularity without an event horizon. Penrose has proposed a conjecture, according to which …

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 …

The process of the gravitational collapse might lead not only to a black hole but also to
naked singularity formation. In this paper, we consider the generalized Vaidya spacetime …

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 …

The final fate of the spherically symmetric collapse of a perfect fluid which follows the γ-law
equation of state and adiabatic condition is investigated. Full general relativistic …