Geometric structures of Morris-Thorne wormhole metric in $f(R,L_m)$ gravity and energy conditions

TL;DR

This paper explores traversable wormhole geometries in $f(R,L_m)$ gravity, demonstrating that certain models can satisfy energy conditions without exotic matter, and provides geometric visualizations for these wormholes.

Contribution

It investigates multiple $f(R,L_m)$ gravity models for wormholes, showing the possibility of satisfying energy conditions without exotic matter, which is a novel insight.

Findings

Null energy condition is satisfied in some models, eliminating the need for exotic matter.

Different $f(R,L_m)$ models produce viable wormhole geometries.

Embedding diagrams illustrate the wormhole structures.

Abstract

The aim of this manuscript is to study the traversable wormhole (WH) geometries in the curvature matter coupling gravity. We investigate static spherically symmetric Morris-Thorne WHs within the context of $f(R,L_m)$ gravity. To accomplish this, we examine the WH model in four different cases (i) linear $f(R,L_m)$ model, $f(R,L_m)=\alpha R+\beta L_m$ with anisotropic matter distribution having the relation $p_r=m p_t$ (ii) linear $f(R,L_m)$ model having anisotropic matter distribution along with the equation of state parameter, $p_r=\omega \rho$, (iii) non-linear model $f(R,L_m)=\dfrac{1}{2}R+L_m^\eta$ with specific form of energy density and (iv) non-linear $f(R,L_m)$ model, $f(R,L_m)=\dfrac{1}{2}R+(1+\xi R)L_m$ with isotropic matter distribution and having the linear relation between pressure and energy density, $p=\omega \rho$. Additionally, in the latter case, we consider a specific power-law shape function $b(r)=r_0 \left(\dfrac{r_0}{r}\right)^n$. Furthermore, we analyze the energy conditions for each WH model to verify their physical viability. As a novel outcome, we can see the validation of the null energy condition for the $f(R,L_m)$ model that suggests ruling out the necessity of exotic matter for the traversability of the WH. At last, an embedding diagram for each model is illustrated that describes the WH geometry.