8 papers
Global Integrated Null Energy Contribution : Classification of Traversable Wormholes
Soumya Chakrabarti
We argue that the local violation of null energy condition at the throat of a traversable wormhole does not necessarily indicate that the total volume integrated null energy contri…
On The Regularized McVittie Black Bounce and a Family of Traversable Wormholes
Soumya Chakrabarti, Chiranjeeb Singha
The McVittie metric describes a self-gravitating compact object embedded in an expanding universe. It inherits two singularities: a curvature singularity at and a cosmolo…
Gravitational Collapse of a Chiellini Integrable Scalar Field
Mohamed Aarif A, Soumya Chakrabarti
We study the gravitational collapse of a non-interacting mix of perfect fluid and a spatially homogeneous scalar field within a Chiellini-integrable framework. We choose an extende…
Oppenheimer-Snyder Collapse in f(R) Gravity : Stalemate or Resolution?
Soumya Chakrabarti, Apratim Ganguly, Radouane Gannouji +1
We study the Oppenheimer--Snyder (OS) collapse problem in metric gravity by matching a homogeneous dust Friedmann--Lemaître--Robertson--Walker (FLRW) interior to a generaliz…
On the stability of the objects of limiting compactness: Black hole and Buchdahl star
Soumya Chakrabarti, Chiranjeeb Singha, Naresh Dadhich
In General Relativity, there exist two objects of limiting compactness, one with a null boundary defining the horizon of a black hole and the other with a timelike boundary definin…
On the Limitations of a Generalized Vaidya Metric
Soumya Chakrabarti, Naresh Dadhich, Chiranjeeb Singha
We prove that there can not be a smooth matching of the Generalized Vaidya metric with an exterior Schwarzschild/Vaidya patch across a finite boundary hypersurface unless the mass…
Traversable Wormholes with Spontaneous Symmetry Breaking
Soumya Chakrabarti, Chiranjeeb Singha
We argue that a spherically symmetric traversable wormhole solution of the Einstein field equations can be supported by minimally coupled self-interacting scalar field which allows…
Self-Similar Collapse in Painleve-Gullstrand Coordinates
Soumya Chakrabarti, Chiranjeeb Singha
We report a family of self-similar exact solutions in General Relativity. The solutions are found in a Painleve-Gullstrand coordinate system but can also be transformed smoothly in…