Test of hybrid metric-Palatini f(R)-gravity in binary pulsars

TL;DR

This paper develops a formalism for testing hybrid metric-Palatini f(R)-gravity using binary pulsar data, deriving constraints and predictions that suggest the theory remains viable in strong gravitational fields.

Contribution

The authors formulated a parameterized post-Keplerian approach for hybrid f(R)-gravity and applied it to pulsar data to constrain the theory's parameters and predict system masses.

Findings

Hybrid f(R)-gravity is not ruled out by current pulsar observations.

Predicted masses of pulsar system components are heavier than in General Relativity.

Constraints on the theory's parameters were derived from PSR J0737-3039 and PSR J1903+0327 data.

Abstract

We developed the parameterized post-Keplerian formalism for hybrid metric-Palatini $f(R)$-gravity. We obtained analytical expressions in the generel eccentric case for four PPK parameters: $\dot\omega$, $\dot P_{\rm b}$, $r$ and $s$. Using observational data of PSR J0737-3039 and PSR J1903+0327 we imposed restrictions on the parameters of hybrid f(R)-gravity and showed that this theory is not ruled out by the observations in strong field regime. In addition we obtained predictions for masses of systems components and found that considered astrophysical objects will be heavier than in GR.