Viable model of anisotropic ultra-dense pulsars $$PSR~J0348+0432$$ and $$PSR~J0030+0451$$ in modified gravity

Abstract This study explores the role of f ( R , T ) gravity in modeling massive pulsars, with particular attention to potential contributions from dark matter effects. We consider a static, spherically symmetric spacetime and derive the modified Einstein field equations for the specific functional form $$ f(R, T) = R + 2\xi T $$ f ( R , T ) = R + 2 ξ T , where $$ \xi $$ ξ denotes the matter-geometry coupling constant. The matter distribution is modeled using a modified Chaplygin equation of state (EoS) to relate the energy density and radial pressure. To observe the physical relevance and viability of the model, two well-known pulsars: $$PSR~J0348+0432$$ P S R J 0348 + 0432 and $$PSR ~J0030+0451$$ P S R J 0030 + 0451 are used. Our analysis demonstrates that for coupling values $$\xi $$ ξ = $$-$$ - 0.1, $$-$$ - 0.2, $$-$$ - 0.3, the central densities range from $$3.43\times 10^{15}\,\textrm{g}~\textrm{cm}^{-3}$$ 3.43 × 10 15 g cm - 3 to $$3.98\times 10^{15}\,\textrm{g}~\textrm{cm}^{-3}$$ 3.98 × 10 15 g cm - 3 , while the surface densities remain near $$1.98\times 10^{15}\,\textrm{g}~\textrm{cm}^{-3}$$ 1.98 × 10 15 g cm - 3 . The central pressure $$p_{r}(0)\sim 3.5\times 10^{34} \,\textrm{dyne}~\textrm{cm}^{-2}$$ p r