Unified Model of k-Inflation, Dark Matter & Dark Energy

TL;DR

This paper introduces a unified scalar field model that explains early universe inflation, dark matter, and dark energy within a single framework, constrained by observational data.

Contribution

It proposes a novel extit{k}-essence model with a specific Lagrangian form that unifies inflation, dark matter, and dark energy, and analyzes observational constraints.

Findings

Model successfully unifies inflation, dark matter, and dark energy.

Observational data constrains model parameters effectively.

The model's late-time behavior matches cosmological observations.

Abstract

We present a \textit{k}-essence model where a single scalar field is responsible for the early expansion of the universe through the process of \textit{k}-inflation and at appropriate subsequent stages acts both as dark matter and dark energy. The Lagrangian contains a potential for the scalar field as well as a non-canonical kinetic term, and is of the form $F(X)V(\phi)$ which has been widely used as a \textit{k}-essence Lagrangian. After the period of inflation is over the model can be approximated as purely kinetic \textit{k}-essence, generating dark matter and dark energy at late times. We show how observational results are used to put constraints on the parameters of this model.