Maximal neutron star mass and the resolution of the hyperon puzzle in modified gravity

The so-called "hyperon puzzle" in the theory of neutron stars is considered in the framework of modified f(R) gravity. We show that for simple hyperon equations of state, it is possible to obtain the maximal neutron star mass which satisfies the recent observational data for PSR J1614-2230, in higher-derivative models with power-law terms as f(R)=R +γR²+βR³. The soft hyperon equation of state under consideration is usually treated as unrealistic in the standard general relativity. The numerical analysis of the mass-radius relation for massive neutron stars with a hyperon equation of state in modified gravity turns out to be consistent with observations. Thus, we show that the same modified gravity can solve at once three problems: a consistent description of the maximal mass of a neutron star, a realistic mass-radius relation, and a method to account for hyperons in the equation of state.