Tests of gravity theories with pulsar timing

TL;DR

Recent pulsar timing experiments have provided the most stringent tests of gravity theories, confirming the strong equivalence principle and constraining alternative models through precise measurements of binary pulsars.

Contribution

This paper reviews recent pulsar timing tests that significantly tighten constraints on violations of the strong equivalence principle and alternative gravity theories.

Findings

No deviations from the SEP detected

Stringent constraints on alternative gravity theories

Complementary to gravitational wave detector results

Abstract

Over the last few years, a set of new results from pulsar timing has introduced much tighter constraints on violations of the strong equivalence principle (SEP), either via a direct verification of the universality of free fall for a pulsar in a triple star system, or from tests of the nature of gravitational waves, in particular a search for dipolar gravitational wave emission in a variety of binary pulsars with different masses. No deviations from the SEP have been detected in our experiments. These results introduce some of the most stringent constraints on several classes of alternative theories of gravity and complement recent results from the ground-based gravitational wave detectors.