Classifying and avoiding singularities in the alternative gravity dark energy models

TL;DR

This paper classifies finite-time singularities in alternative gravity dark energy models, analyzes conditions for avoiding them, and explores modifications to prevent singularities, with implications for relativistic star formation.

Contribution

It provides a detailed classification of singularities in gravity dark energy models and proposes methods to avoid them using higher-order curvature corrections.

Findings

Singularities can occur even in flat spacetime for certain potentials.

Conditions for avoiding finite-time singularities are identified.

Higher-order curvature corrections can cure singularities.

Abstract

The future finite-time singularities emerging in alternative gravity dark energy models are classified and studied in Jordan and Einstein frames. It is shown that such singularity may occur even in flat spacetime for the specific choice of the effective potential. The conditions for the avoidance of finite-time singularities are presented and discussed. The problem is reduced to the study of a scalar field evolving on an effective potential by using the conformal transformations. Some viable modified gravity models are analyzed in detail and the way to cure singularity is considered by introducing the higher-order curvature corrections. These results maybe relevant for the resolution of the conjectured problem in the relativistic star formation in such modified gravity where finite-time singularity is also manifested.