Abstract In this paper, we review some anisotropic stellar spheres in the framework of modified f ( R , G ) gravity. For this purpose, we have capitalized the Tolman-Kuchowicz spacetime Tolman (1939) ; Kuchowicz (1968) . The equations of motion have been formulated by considering anisotropic matter distribution along with metric potentials, a = B r 2 + 2 l n C and b = l n ( 1 + α r 2 + β r 4 ) . To determine the new constraints, observational data of 4 U 1538 − 52 , H e r X − 1 and S A X J 1808.4 − 3658 have been pre-owned. Dynamical equations have been evaluated by making use of Starobinsky model f ( R , G ) = R + λ R 2 + G 2 . Many physical aspects have been enlightened, such as energy density, pressure evolutions, adiabatic index, TOV equations and surface redshift. The credibility of our presented model has been confirmed by observing the evolution of some physical aspects and it is concluded that our system is free from all singularities and is physically stable.

中文翻译：

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具有托尔曼-库乔维奇时空的 f(R,G) 重力各向异性球体

摘要 本文在修正f ( R , G ) 引力的框架内回顾了一些各向异性的恒星球体。为此，我们将 Tolman-Kuchowicz 时空 Tolman (1939) 大写；库乔维奇 (1968)。通过考虑各向异性物质分布和度量势，a = B r 2 + 2 ln C 和 b = ln ( 1 + α r 2 + β r 4 ) 已经制定了运动方程。为了确定新的约束条件，4 U 1538 − 52 、H er X − 1 和SAXJ 1808.4 − 3658 的观测数据已经被预先拥有。动力学方程已通过使用 Starobinsky 模型 f ( R , G ) = R + λ R 2 + G 2 进行评估。许多物理方面已经得到启发，例如能量密度、压力演化、绝热指数、TOV 方程和表面红移。