Enhanced power of gravitational waves and rapid coalescence of black hole binaries through dark energy accretion

TL;DR

This paper investigates how dark energy accretion onto black hole binaries enhances gravitational wave emission and accelerates their coalescence, suggesting observable effects in gravitational wave astronomy.

Contribution

It introduces a model of dark energy accretion that significantly increases black hole masses and gravitational wave power, reducing binary coalescence times.

Findings

Dark energy accretion increases black hole masses.

Enhanced gravitational wave power observed.

Binary coalescence occurs faster due to accretion.

Abstract

We consider the accretion of dark energy by constituent black holes in binary formations during the present epoch of the Universe. In the context of an observationally consistent dark energy model, we evaluate the growth of black holes' masses due to accretion. We show that accretion leads to faster circularization of the binary orbits. We compute the average power of the gravitational waves emitted from binaries, which exhibits a considerable enhancement due to the effect of growth of masses as a result of accretion. This in turn, leads to a significant reduction of the coalescence time of the binaries. We present examples pertaining to various choices of the initial masses of the black holes in the stellar mass range and above, in order to clearly establish a possible observational signature of dark energy in the emerging era of gravitational wave astronomy.