Constraining the time variation of Newton's constant $G$ with gravitational-wave standard sirens and supernovae

TL;DR

This paper proposes a method to constrain the possible time variation of Newton's constant G over different redshifts by combining gravitational-wave standard sirens from binary neutron star mergers with Type Ia supernovae data, achieving a 1.5% precision.

Contribution

It introduces a model-independent approach using GW standard sirens and SNIa to measure G's variation across redshifts, enhancing previous methods.

Findings

Achieves 1.5% constraint on G/G0 over redshift range

Demonstrates the effectiveness of combining GW and SNIa data

Provides a new way to test fundamental physics with upcoming observations

Abstract

The intrinsic peak luminosity of Type Ia supernovae (SNIa) depends on the value of Newton's gravitational constant $G$, through the Chandrasekhar mass $M_{\rm Ch}\propto G^{-3/2}$. If the luminosity distance can be independently determined, the SNIa can be treated as a tracker to constrain the possible time variation of $G$ in different redshift ranges. The gravitational-wave (GW) standard sirens, caused by the coalescence of binary neutron stars, provide a model-independent way to measure the distance of GW events, which can be used to determine the luminosity distances of SNIa by interpolation, provided the GW and SNIa samples have similar redshift ranges. We demonstrate that combining the GW observations of third-generation detectors with SNIa data provides a powerful and model-independent way to measure $G$ in a wide redshift range, which can constrain the ratio $G/G_0$, where $G$ and $G_0$ are respectively the values in the redshift ranges $z>0.1$ and $z<0.1$, at the level of $1.5\%$.