Phantom cosmologies

TL;DR

This paper explores a class of phantom cosmological models with unusual singularities and reveals a duality symmetry with standard matter models, expanding understanding of alternative universe scenarios.

Contribution

It introduces a new class of phantom cosmologies with unique singularity behavior and uncovers a duality relation with standard matter models.

Findings

Singularities occur at infinite scale factor values.

Phantom models exhibit different singularity types compared to standard cosmology.

A duality symmetry links phantom and standard matter cosmologies.

Abstract

We discuss a class of phantom ($p < - \varrho$) cosmological models. Except for phantom we admit various forms of standard types of matter and discuss the problem of singularities for these cosmologies. The singularities are different from those of standard matter cosmology since they appear for infinite values of the scale factor. We also find an interesting relation between the phantom models and standard matter models which is like the duality symmetry of string cosmology.