166 citations · 427 across the 9 of their papers we have counts for
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Scalar wave scattering from Schwarzschild black holes in modified gravity
Dan B. Sibandze, Rituparno Goswami, Sunil D. Maharaj +2
We consider the scattering of gravitational waves off a Schwarzschild black hole in gravity. We show that the reflection and transmission coefficients for tensor waves are t…
Buchdahl-Bondi limit in modified gravity: Packing extra effective mass in relativistic compact stars
Rituparno Goswami, Sunil D. Maharaj, Anne Marie Nzioki
We generalise the Buchdahl-Bondi limit for the case of static, spherically symmetric, relativistic compact stars immersed in Schwarzschild vacuum in f(R)-theory of gravity, subject…
Collapsing spherical stars in f(R) gravity
Rituparno Goswami, Anne Marie Nzioki, Sunil. D. Maharaj +1
We perform a careful investigation of the problem of physically realistic gravitational collapse of massive stars in f(R)-gravity. We show that the extra matching conditions that a…
Vibrating Black Holes in f(R) gravity
Anne Marie Nzioki, Rituparno Goswami, Peter K. S. Dunsby
We consider general perturbations of a Schwarzschild black holes in the context of f(R) gravity. A reduced set of frame independent master variables are determined, which obey two…
Jebsen-Birkhoff theorem and its stability in f(R) gravity
Anne Marie Nzioki, Rituparno Goswami, Peter K. S. Dunsby
We prove a Jebsen-Birkhoff like theorem for f(R) theories of gravity in order to to find the necessary conditions required for the existence of the Schwarzschild solution in these…
On the absence of the usual weak-field limit, and the impossibility of embedding some known solutions for isolated masses in cosmologies with f(R) dark energy
Timothy Clifton, Peter Dunsby, Rituparno Goswami +1
The problem of matching different regions of spacetime in order to construct inhomogeneous cosmological models is investigated in the context of Lagrangian theories of gravity cons…
On Shear-Free perturbations of FLRW Universes
Anne Marie Nzioki, Rituparno Goswami, Peter K. S. Dunsby +1
A surprising exact result for the Einstein Field Equations is that if pressure-free matter is moving in a shear-free way, then it must be either expansion-free or rotation-free. It…
A Geometrical Approach to Strong Gravitational Lensing in f(R) Gravity
Anne Marie Nzioki, Peter K. S. Dunsby, Rituparno Goswami +1
We present a framework for the study of lensing in spherically symmetric spacetimes within the context of f(R) gravity. Equations for the propagation of null geodesics, together wi…
A new framework for studying spherically symmetric static solutions in f(R) gravity
Anne Marie Nzioki, Sante Carloni, Rituparno Goswami +1
We develop a new covariant formalism to treat spherically symmetric spacetimes in metric} f(R) theories of gravity. Using this formalism we derive the general equations for a stati…