Self-bound isotropic models in f(Q) gravity and effect of f(Q) parameter on mass–radius relation and stability of compact objects

Abstract

The present article investigates the effect of $f\left(Q\right)$ parameters on two classes of exact spherically symmetric self-bound isotropic solutions for compact objects. The field equation in $f\left(Q\right)$ gravity is solved using Korkina–Orlyanskii and Buchdahl models. The physical validity of both models has been verified using regularity, stability, and hydrostatic equilibrium tests. We have also shown the effect of $f\left(Q\right)$ gravity parameter $\alpha$ on the stability and mass–radius relation. We predicted the radii of observable compact objects GW 190814, PSR J0740+6620 PSR J1614, 2230, Cen X-3, and LMC X-4. In the absence of $\beta$, the massive neutron star GW 190814 is detected at greater values of $\alpha =1.5$ and 1.2 for models I and II respectively. The corresponding estimated radii for both models are $15.30_{-0.29}^{+0.18}\mathrm{km}$ and $15.03_{-0.25}^{+0.17}\mathrm{km}$. Additionally, as the non-metricity scalar $\alpha$ increases, the mass–radius decreases, and when $\beta$ increases with fix $\alpha$, the reverse scenario arises. Our finding indicates that a lower $mass-gap$ can be achieved in $f\left(Q\right)$ gravity theory as compared to the standard theory of gravity.