Sudden singularities in semiclassical gravity

TL;DR

This paper reviews claims about the persistence of sudden singularities in semiclassical gravity, demonstrating that quantum effects can significantly alter their behavior under various conditions.

Contribution

It clarifies the conditions under which sudden singularities may or may not survive in semiclassical gravity, providing explicit examples and highlighting the role of quantum effects.

Findings

Quantum effects can modify the behavior of sudden singularities.

The survival of singularities depends on specific conditions.

Explicit example shows quantum effects can prevent singularities.

Abstract

It has been claimed in a recent paper \cite{bbfhd12} that sudden singularities will survive in semiclassical gravity. This issue is here carefully reviewed, pointing out that such conclusion, even if valid under some specific conditions, does not stand in other cases. An explicit example is studied in detail to support our statement, stemming from these other situations, that quantum effects may in fact drastically modify the behavior of sudden singularities.