# Gravitational Radiation from Close Binaries with Time-Varying Masses

## TL;DR

This paper extends the understanding of gravitational waves from close binaries by including effects of time-varying masses, showing these can significantly amplify gravitational radiation beyond orbital contributions.

## Contribution

It introduces phase-dependent formulas for gravitational radiation from binaries with changing masses, expanding upon the classical Peters and Mathews model.

## Key findings

- Mass variation effects can dominate gravitational wave emission.
- Derived formulas reduce to classical results for constant masses.
- Mass changes can increase gravitational radiation by orders of magnitude.

## Abstract

In the quadrupole approximation of General Relativity in the weak-field limit, a time-varying quadrupole moment generates gravitational radiation. Binary orbits are one of the main mechanisms for producing gravitational waves and are the main sources and backgrounds for gravitational-wave detectors across the multi-band spectrum. In this Paper, we introduce additional contributions to the gravitational radiation from close binaries that arise from time-varying masses along with those produced by orbital motion. We derive phase-dependent formulae for these effects in the quadrupolar limit for binary point masses, which reduce to the formulae that Peters and Mathews (1963) derived when the mass of each component is taken to be constant. We show that gravitational radiation from mass variation can be orders of magnitude greater than that of orbital motion.