Charged stars in 4D Einstein–Gauss–Bonnet gravity

Abstract

An alternative gravity theory that has attracted considerable attention recently is the novel four-dimensional Einstein–Gauss–Bonnet (4EGB) gravity. This idea was proposed to bypass the Lovelock’s theorem and to permit nontrivial higher curvature effects on the four-dimensional local gravity. In this approach, the Gauss–Bonnet (GB) coupling constant $$\alpha $$ α is rescaled by a factor of $$\alpha /(D -4)$$ α / ( D - 4 ) in D dimensions and taking the limit $$D \rightarrow 4$$ D → 4 . In this article, we analyze the effects of charge on static compact stars in the regularized 4D EGB gravity theory. Two classes of new exact solutions are found for a particular choice of the gravitational potential and assuming a relationship between the electric field intensity and the spatial potential. A graphical analysis indicates that the matter and electromagnetic variables are well behaved for specific values of the parameter space. Finally, based on physical grounds appropriate bounds on the model parameters we show that compact objects with the value of adiabatic index $$\gamma $$ γ is consistent with expectations.

Relativistic wormhole surrounded by dark matter halos in symmetric teleparallel gravity

“…It is relevant to mention that some of us had recently calculated new traversable wormhole families of solutions in $$f(Q)$$ [ 81,82 ] by using the embedded spacetime and non‐commutative geometry within the conformal symmetry. Later, Banerjee and his coauthors [ 83 ] systematically studied the field equations for wormhole solutions and found the violation of null energy conditions in the throat neighborhood. Recently, Sharma and Mishra [ 84 ] have discussed the traversable wormhole solutions with non‐exotic fluid in $$f(Q)$$ gravity.…”

Black Hole Solutions with Dark Matter Halos in the Four‐Dimensional Einstein‐Gauss‐Bonnet Gravity

“…Invoking the partial waves approach Lima Junior et al [38] showed that the cross-section of planar scalar massless waves are impacted by the GB coupling constant in 4D EGB. Charged stars, [39] wormholes, [40] gravitational lensing, [41] isotropic perfect fluids [42] and Born-Infeld BHs [43] have been investigated recently. Wang and Ge [44] considered the coupling of 4D EGB-charged BHs with a scalar field.…”

Anisotropic Compact Stars in D → 4 Limit of Gauss–Bonnet Gravity

“…The Kaluza-Klein reduction method of the limit D → 4 yields a special class of scalar-tensor theories in the Horndeski family [97,98]. Similar method was used in [88,99,100] by adding a counter term in D-dimensions and then taking D → 4 limit. Furthermore, many projects have been analyzed the previous issues coming from the new 4-dimensions EGB gravity.…”