Local Conformal Instability and Local Non-Collapsing in the Ricci flow of Quantum Spacetime

TL;DR

This paper investigates conformal instability in quantum spacetime using Ricci flow within the Quantum Spacetime Reference Frame, showing local stability conditions and that such instability does not lead to spacetime collapse, ensuring overall stability.

Contribution

It introduces a framework combining Ricci flow and quantum spacetime to analyze conformal stability and proves local non-collapsing results ensuring global spacetime stability.

Findings

Local conformal instability depends on the eigenvalues of an associated operator.

Local non-collapsing theorem prevents spacetime collapse despite instability.

Total effective action remains positive and bounded, ensuring overall stability.

Abstract

It is known that the conformal instability or bottomless problem rises in the path integral method in quantizing the general relativity. Does quantum spacetime itself really suffer from such conformal instability? If so, does the conformal instability cause the collapse of local spacetime region or even collapse the whole spacetime? The problems are studied in the framework of the Quantum Spacetime Reference Frame (QSRF) and induced spacetime Ricci flow. We find that if the lowest eigenvalue of an operator, associated with the F-functional in a local compact (closed and bounded) region, is positive, the local region is conformally unstable and will tend to volume-shrinking and curvature-pinching along the Ricci flow-time t; if the eigenvalue is negative or zero, the local region is conformally stable up to a trivial rescaling. However, the local non-collapsing theorem in the Ricci flow proved by Perelman ensures that the instability will not cause the local compact spacetime region collapse into nothing. The total effective action is also proved positive defined and bounded from below keeping the whole spacetime conformally stable, which can be considered as a generalization of the classical positive mass theorem of gravitation to the quantum level.