A Brief analysis of isotropic Karmarkar models in modified gravity theory

Feng Y., Naseer T., Ashraf A., SOFUOĞLU D., Abdullayeva I.

Chinese Journal of Physics, vol.90, pp.372-386, 2024 (SCI-Expanded) identifier

  • Publication Type: Article / Article
  • Volume: 90
  • Publication Date: 2024
  • Doi Number: 10.1016/j.cjph.2024.05.019
  • Journal Name: Chinese Journal of Physics
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, INSPEC, zbMATH
  • Page Numbers: pp.372-386
  • Keywords: Compact model, Geometric deformation, Modified gravity
  • Istanbul University Affiliated: Yes


This investigation explores the nature of charged compact stars within the modified theory whose functional depends on the Ricci scalar, Lagrangian density of the matter and trace of the energy–momentum tensor. The methodology involves starting with a static spherical spacetime filled with the isotropic fluid. The field equations are then formulated corresponding to a specific minimal model of this extended theory. While developing these equations, we also take into account different choices of the fluid Lagrangian density. Further, we use the Karmarkar condition to deal with the extra degrees of freedom in the equations of motion and construct their corresponding solutions. The metric components obtained from the Karmarkar condition possess three constants which are evaluated through the matching conditions of the interior spherical geometry with the exterior vacuum spacetime. Further, we explore the obtained models for different values of the parameters through a comprehensive graphical analysis. Conclusively, our results agree well with the physical conditions and thus advance our understanding of the impact of the considered gravity theory on the internal composition of stellar objects.