Isotropization and complexity analysis of decoupled solutions in $$f({\mathbb {R}},{\mathbb {T}})$$ theory

Abstract

This paper formulates some new exact solutions to the field equations by means of minimal gravitational decoupling in the context of \(f({\mathbb {R}},{\mathbb {T}})\) gravity. For this purpose, we consider anisotropic spherical matter distribution and add an extra source to extend the existing solutions. We apply the transformation only on the radial metric potential that results in two different sets of the modified field equations, each of them corresponding to their parent source. The initial anisotropic source is represented by the first set, and we consider two different well-behaved solutions to close that system. On the other hand, we impose constraints on the additional source to make the second set solvable. We, firstly, employ the isotropization condition which leads to an isotropic system for a particular value of the decoupling parameter. We then use the condition of zero complexity of the total configuration to obtain the other solution. The unknowns are determined by smoothly matching the interior and exterior spacetimes at the hypersurface. The physical viability and stability of the obtained solutions are analyzed by using the mass and radius of a compact star \(4U 1820-30\). It is concluded that both of our extended solutions meet all the physical requirements for considered values of the coupling/decoupling parameters.