Palatini wormholes and energy conditions from the prism of General Relativity

TL;DR

This paper explores Palatini wormholes within modified gravity theories, analyzing their energy condition violations and how these relate to their interpretation in standard General Relativity.

Contribution

It introduces wormhole solutions derived from Palatini gravity actions and reinterprets them within the framework of General Relativity, examining energy condition violations.

Findings

Wormholes violate energy conditions in standard GR.

Modified gravity can alter the perceived matter sources.

Energy condition violations vary with different Palatini models.

Abstract

Wormholes are hypothetical shortcuts in spacetime that in General Relativity unavoidably violate all of the pointwise energy conditions. In this paper, we consider several wormhole spacetimes that, as opposed to the standard \emph{designer} procedure frequently employed in the literature, arise directly from gravitational actions including additional terms resulting from contractions of the Ricci tensor with the metric, and which are formulated assuming independence between metric and connection (Palatini approach). We reinterpret such wormhole solutions under the prism of General Relativity and study the matter sources that thread them. We discuss the size of violation of the energy conditions in different cases, and how this is related to the same spacetimes when viewed from the modified gravity side.