Stellar Oscillations in Tensor-Vector-Scalar Theory

TL;DR

This paper investigates neutron star oscillations within TeVeS gravity, revealing potential observational signatures in gravitational waves that could distinguish it from general relativity.

Contribution

It provides the first analysis of neutron star oscillation spectra in TeVeS theory using the Cowling approximation, highlighting differences from general relativity in strong-field regimes.

Findings

Fundamental mode frequencies are higher in TeVeS than in GR.

Higher overtone frequencies show stronger dependence on the gravitational theory.

Potential gravitational wave signatures could confirm the scalar field presence.

Abstract

An alternative theory of gravity has recently been proposed by Bekenstein, named Tensor-Vector-Scalar (TeVeS) theory, which can explain many galactic and cosmological observations without the need for dark matter. Whilst this theory passes basic solar system tests, and has been scrutinized with considerable detail in other weak-field regimes, comparatively little has been done in the strong-field limit of the theory. In this article, with Cowling approximation, we examine the oscillation spectra of neutron stars in TeVeS. As a result, we find that the frequencies of fundamental modes in TeVeS could become lager than those expected in general relativity, while the dependence of frequency of higher overtone on gravitational theory is stronger than that of lower modes. These imprints of TeVeS make it possible to distinguish the gravitational theory in strong-field regime via the observations of gravitational waves, which can provide unique confirmation of the existence of scalar field.