# Cosmological Solutions in Multiscalar Field Theory

## TL;DR

This paper explores exact cosmological solutions in a multiscalar field theory with mixed kinetic terms, revealing conditions for unified dark matter and dark energy scenarios.

## Contribution

It introduces a methodology linking scalar field functions to scale factor behavior and identifies conditions for unified dark sector solutions.

## Key findings

- Existence of exact cosmological solutions with mixed scalar fields.
- Conditions for scalar functions to admit dark matter and dark energy unification.
- Methodology relating scale factor evolution to scalar field functions.

## Abstract

We consider a cosmological model with two scalar fields minimally coupled to gravity which have a mixed kinetic term. Hence, Chiral cosmology is included in our analysis. The coupling function and the potential function, which depend on one of the fields, characterize the model we study. We prove the existence of exact solutions that are of special interest for the cosmological evolution. Furthermore, we provide with a methodology that relates the scale factor behaviour to the free functions characterizing the scalar field kinetic term coupling and potential. We derive the necessary conditions that connect these two functions so that the relative cosmological solutions can be admitted. We find that unified dark matter and dark energy solutions are allowed by the theory in various scenarios involving the aforementioned functions.