Noncommutative-geometry wormholes without exotic matter

TL;DR

This paper demonstrates that noncommutative geometry, related to string theory, can support wormholes without exotic matter by acting as a special case of $f(R)$ gravity, which violates the NEC effectively.

Contribution

It shows that noncommutative geometry can sustain wormholes without exotic matter, linking it to $f(R)$ gravity and providing a new perspective on wormhole physics.

Findings

Noncommutative geometry can be viewed as a special case of $f(R)$ gravity.

Wormholes can be sustained without exotic matter in this framework.

The effective stress-energy tensor violates NEC while matter satisfies it.

Abstract

A fundamental property of Morris-Thorne wormholes is the so-called flare-out condition that automatically results in a violation of the null energy condition (NEC) in classical general relativity. By contrast, in $f(R)$ modified gravity, the material threading the wormhole may actually satisfy the NEC, while, at the same time, the effective stress-energy tensor arising from the modified theory violates the NEC, thereby sustaining the wormhole. It is shown in this paper that noncommutative geometry, an offshoot of string theory, can be viewed as a special case of $f(R)$ gravity and can therefore sustain a wormhole without the use of exotic matter. It also provides a motivation for the choice of $f(R)$ in the modified gravitational theory.