Improved binary pulsar constraints on the parametrized post-Einsteinian framework

Abstract

The parametrized post-Einsteinian formalism was developed to search for generic deviations from general relativity with gravitational waves. We here present constraints on this framework using Bayesian analysis of a set of binary pulsar observations. In particular, we use measurements of the Keplerian and post-Keplerian parameters of six different binary pulsar systems, and Markov-Chain Monte-Carlo exploration to calculate posteriors on the parametrized post-Einsteinian parameters and derive robust constraints. We find improvements of 1–2 orders of magnitude in the strength of constraints when combining all six observations, relative to what one can achieve when using only the double binary pulsar. We also find that the constraints are robust to any correlation with the binary’s component masses. The bounds on the parametrized post-Einsteinian framework derived here could be used as a prior in future Bayesian tests of general relativity with gravitational wave observations.