Preheating and Dark Sector of Universe

TL;DR

This paper explores a model where particles from preheating act as dark matter, influencing the universe's expansion by creating a false vacuum that mimics dark energy, with dynamics constrained by cosmological observations.

Contribution

It proposes a novel scenario linking preheating-produced particles to dark energy and dark matter, with detailed analysis of the field dynamics and observational constraints.

Findings

False vacuum can drive late-time cosmic acceleration.

Dark matter particle density affects the transition to true vacuum.

Model parameters are constrained by dark energy and halo observations.

Abstract

Regarding long life particles produced during preheating after inflation as dark matter, we find that its back reaction on the field $\phi$ could lock $\phi$ in a false vacuum up to today. This false vacuum can drive the accelerated expansion of universe at late time and play the role of dark energy. When the number density of dark matter particles is dilute to some value, the field $\phi$ becomes tachyonic and rolls to its true minima rapidly, and the acceleration of universe ceases. We discuss the constraints on the parameters of model from the observations of dark energy and dark matter halos on subgalactic scale.