Strange stars in $f(R)$ theories of gravity in the Palatini formalism

Understand

In the present work we study strange stars in $f(R)$ theories of gravity in the Palatini formalism.

• We consider two concrete well-known cases, namely the $R+R^2/(6 M^2)$ model as well as the $R-\mu^4/R$ model for two different values of the mass parameter $M$ or $\mu$.
• We integrate the modified Tolman-Oppenheimer-Volkoff equations numerically, and we show the mass-radius diagram for each model separately.
• The standard case corresponding to the General Relativity is also shown in the same figure for comparison.