Improved Bounds on Violation of the Strong Equivalence Principle

TL;DR

This paper reports a 20-year timing study of a binary pulsar that sets new limits on dipolar gravitational radiation, testing the validity of the Strong Equivalence Principle in strong gravity regimes.

Contribution

It provides the first long-term observational bounds on violations of the Strong Equivalence Principle using pulsar timing data.

Findings

No evidence of dipolar gravitational radiation detected.

New constraints on violations of the Strong Equivalence Principle.

Extended timing data improves bounds on alternative gravity theories.

Abstract

I describe a unique, 20-year-long timing program for the binary pulsar B0655+64, the stalwart control experiment for measurements of gravitational radiation damping in relativistic neutron-star binaries. Observed limits on evolution of the B0655+64 orbit provide new bounds on the existence of dipolar gravitational radiation, and hence on violation of the Strong Equivalence Principle.