Energy conditions in new model of loop quantum cosmology

TL;DR

This paper analyzes how quantum corrections in a new loop quantum cosmology model violate standard energy conditions, especially around the bounce and de Sitter phases, impacting exotic spacetime constructions.

Contribution

It provides explicit calculations of energy condition violations in a new LQC model with a de Sitter epoch, highlighting the behavior of various energy conditions during cosmic evolution.

Findings

Null energy condition is violated during the bounce.

Dominant energy condition is violated only near the bounce.

Strong energy condition is violated throughout the bounce and de Sitter phases.

Abstract

Recently, a de-Sitter epoch has been found in the new model of loop quantum cosmology which is governed by the scalar constraint with both of Euclidean and Lorentz terms. The singularity free bounce in the new LQC model and the emergent cosmology constant strongly suggest that the effective stress energy tensor induced by quantum corrections must violate the standard energy conditions. In this paper, we do an explicit calculation to analyze the behaviours of specific representative energy conditions, i.e., average null, strong and dominant energy conditions. It turns out that the averaging null energy condition is violated while the dominant energy condition is violated only at a period around the bounce point. More specifically, the strong energy condition is violated not only at a period around the bounce point, but also the whole period from the bounce point to the classical phase corresponding to the de Sitter period. Our results is expected to shed some lights on construction of the wormhole and time machine which usually need exotic matters violate energy conditions.