Massive Compact Stars Beyond the General Relativity Limit in Finslerian Gravity: A Possible Explanation for the GW190814 Secondary
Massive Compact Stars Beyond the General Relativity Limit in Finslerian Gravity: A Possible Explanation for the GW190814 Secondary
Praveen J, Rajesh Kumar, Sadaf Fatima, S K Narasimhamurthy
AbstractThe existence of an upper mass limit for compact stars is one of the fundamental predictions of general relativity (GR), with important implications for the outcome of compact binary mergers and the nature of the proposed neutron star black hole mass gap. The LIGO Virgo collaboration announced the discovery of a compact binary merger, GW190814, containing a compact star with mass 2.5 to 2.67 $M_\odot$ [R. Abbott et al.(2020) ApJ Lett., 896, L44], which provided an exciting new stimulus to the ongoing debate on whether a gap exists between the maximum mass of NS and the minimum mass of black hole. Such GW detection has also challenged conventional stellar models and renewed interest in exploring whether modified theories of gravity can accommodate such ultra-massive compact objects without invoking black hole formation. The present work investigated the structure and physical properties of compact stars within the framework of Finslerian gravity, employing the Heintzmann IIa gravitational potentials and showed that the our model can substantially enhance the maximum mass of compact stars upto $2.67 M_{\odot}$, thereby offering a plausible explanation for massive compact objects such as the secondary component of GW190814. In addition, the moment of inertia is found to increase, indicating stronger rotational support and a redistribution of the internal mass profile. The analysis focuses on key astrophysical observables, including the mass radius and moment of inertia mass relations, and a detailed comparison with the GR counterpart is performed. Assuming a linear equation of state, we construct a class of physically viable anisotropic stellar models and analyze their behavior under the influence of Finslerian corrections. The physical viability of the model is rigorously tested through stability criteria.