A test of gravity with Pulsar Timing Arrays

被引：16

作者：

Liang, Qiuyue ^{[1
]}

Lin, Meng-Xiang ^{[1
]}

Trodden, Mark ^{[1
]}

机构：

[1] Univ Penn, Ctr Particle Cosmol, Dept Phys & Astron, Philadelphia, PA 19104 USA

来源：

JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS | 2023年 / 11期

关键词：

gravitational waves / theory; Gravitational waves in GR and beyond: theory; particle physics-cosmology connection;

D O I：

10.1088/1475-7516/2023/11/042

中图分类号：

P1 [天文学];

学科分类号：

0704 ;

摘要：

A successful measurement of the Stochastic Gravitational Wave Background (SGWB) in Pulsar Timing Arrays (PTAs) would open up a new window through which to test the predictions of General Relativity (GR). We consider how these measurements might reveal deviations from GR by studying the overlap reduction function - the quantity that in GR is approximated by the Hellings-Downs curve - in some sample modifications of gravity, focusing on the generic prediction of a modified dispersion relation for gravitational waves. We find a distinct signature of such modifications to GR - a shift in the minimum angle of the angular distribution - and demonstrate that this shift is quantitatively sensitive to any change in the phase velocity. In a given modification of gravity, this result can be used, in some regions of parameter space, to distinguish the effect of a modified dispersion relation from that due to the presence of extra polarization modes.

引用

页数：19