Interacting fluids generating identical, dual and phantom cosmologies

TL;DR

This paper explores symmetry transformations in flat FRW cosmologies with interacting fluids, revealing dualities between different expansion scenarios including phantom and superaccelerated universes, and analyzes their effects on various scalar field models.

Contribution

It identifies a symmetry group linking different cosmological solutions and examines its impact on scalar field models like quintessence and k-essence.

Findings

Discovered a symmetry group connecting identical, dual, and phantom cosmologies.

Established dualities between contracting and superaccelerated expansion.

Analyzed the symmetry group's action on scalar field cosmologies.

Abstract

We find the group of symmetry transformations generated by interacting fluids in spatially flat Friedmann-Robertson-Walker (FRW) spacetime which links cosmologies with the same scale factor {\it (identity)} or with scale factors $a$ and $a^{-1}$ {\it (duality)}. There exists a duality between contracting and superaccelerated expanding scenarios associated with {\it (phantom)} cosmologies. We investigate the action of this symmetry group on self-interacting minimally(conformally) coupled quintessence and $k$-essence cosmologies.