Rajes Ghosh

Black hole solutions of general relativity exhibit a symmetry for the static perturbations around these spacetimes, known as “ladder symmetry.” This symmetry proves useful in constructing a tower of solutions for perturbations and elucidating their general properties. Specifically, the presence of this symmetry leads to the vanishing of the tidal Love number associated with black holes.

We investigate the ergoregion instability of area-quantized rotating quantum black holes (QBH) under gravitational perturbation. We show that the instability can be avoided in binary systems that include QBHs if the separation between the inspiraling components at the onset of black hole formation is less than a critical value.

The second postulate of special relativity states that the speed of light in vacuum is independent of the emitter’s motion. The test of this postulate so far remains unexplored for gravitational radiation. We analyze data from the LIGO-Virgo detectors to test this postulate within the ambit of a model where the speed of the emitted GWs (c′) from a binary depends on a characteristic velocity v˜ proportional to that of the reduced one-body system as c′=c+kv˜, where k is a constant.