Existence of non-exotic traversable wormholes in squared trace extended gravity theory

TL;DR

This paper investigates the existence of non-exotic matter traversable wormholes within a squared trace extended gravity framework, analyzing energy conditions for different geometries and identifying narrow parameter ranges where such wormholes could exist.

Contribution

It introduces a modified gravity model with linear and quadratic trace terms and explores conditions under which non-exotic wormholes can be realized.

Findings

Non-exotic wormholes may satisfy null energy conditions depending on geometry.

Existence of such wormholes is sensitive to model parameters and geometry.

Possible only within narrow parameter ranges for specific equations of state.

Abstract

An extended gravity theory is used to explore the possibility of non-exotic matter traversable wormholes. In the extended gravity theory, additional terms linear and quadratic in the trace of the energy momentum tensor are considered in the Einstein-Hilbert action. Obviously, such an addition leads to violation of the energy-momentum tensor. The model parameters are constrained from the structure of the field equations. Non-exotic matter wormholes tend to satisfy the null energy conditions. We use two different traversable wormhole geometries namely an exponential and a power law shape functions to model the wormholes. From a detailed analysis of the energy conditions, it is found that, the existence of non-exotic matter traversable wormholes is not obvious in the model considered and its possibility may depend on the choice of the wormhole geometry. Also, we found that, non-exotic wormholes are possible within the given squared trace extended gravity theory for a narrow range of the chosen equation of state parameter.