On tachyon and sub-quantum phantom cosmologies

TL;DR

This paper explores tachyon and sub-quantum dark energy models, showing that they can lead to a big rip singularity, with scalar fields needing to be Wick rotated to imaginary values for these regimes.

Contribution

It introduces analytical solutions for these models that satisfy all constraints and demonstrate the development of a big rip singularity in finite future.

Findings

Models predict a big rip singularity in finite time.

Scalar fields are Wick rotated to imaginary values for phantom regimes.

Analytical expressions satisfy all model constraints.

Abstract

This paper deals with dark and phantom energy in the tachyon and sub-quantum models for dark energy. We obtain that the simplest condition for such a regime to occur in these scenarios is that the scalar field be Wick rotated to imaginary values which correspond to an axionic field classically. By introducing analytical expressions for the scale factor or the Hubble parameter that satisfy all constraint equations of the used models we show that such models describe universes which develop a big rip singularity in the finite future.