Thermodynamics of irreversible particle creation phenomena and its cosmological consequence

TL;DR

This paper explores the thermodynamics of irreversible particle creation in cosmology, proposing it as a potential explanation for both early universe reheating and late-time cosmic acceleration without dark energy.

Contribution

It develops a thermodynamic framework for irreversible particle creation and analyzes its implications for cosmic evolution, offering an alternative to dark energy and modified gravity theories.

Findings

Particle creation can drive late-time cosmic acceleration.

Reheating of the universe can be explained by particle creation after inflation.

Cosmic evolution can be modeled without dark energy or modified gravity.

Abstract

The study of particle creation phenomena at the expense of the gravitational field is of great research interest. It might solve the cosmological puzzle single-handedly, without the need for either dark energy or the modified theory of gravity. In the early universe, following graceful exit from inflationary phase, it serves the purpose of reheating the cold universe, which gave way to the hot Big-Bang model. In the late universe, it led to late time cosmic acceleration, without affecting stand-ard Big-Bang-Nucleosynthesis (BBN), Cosmic Microwave Background Radiation (CMBR), or Structure Formation. In this chapter, we briefly review the present status of cosmic evolution, develop the thermodynamics for irreversible particle creation phenomena and study its consequences at the early as well as in the late universe.