Massive particle pair production and oscillation in Friedman Universe: dark energy and matter interaction

TL;DR

This paper investigates how quantum particle pair production and oscillation in a Friedman universe influence dark energy and matter interaction, providing a mechanism for cosmic coincidence and proposing new effective models for dark energy.

Contribution

It introduces a quantum field approach to particle production in cosmology, linking microscopic pair dynamics to macroscopic dark energy-matter interactions and cosmic evolution.

Findings

Particle-antiparticle pairs are produced and oscillate on microscopic time scales.

A massive pair plasma forms, affecting the Friedman equations and cosmic dynamics.

Dark energy tracks radiation in the early universe and transitions to positive in the matter epoch.

Abstract

The classical Friedman equations of time-varying Hubble function $H$, dark-energy and matter densities couple to quantised field equations for massive modes $M\gg H$. Numerically solving these equations, we show the particle-antiparticle pairs production and oscillation in microscopic time scale ${\mathcal O}(M^{-1})$. A massive pair plasma state is formed in macroscopic time scale ${\mathcal O}(H^{-1})$. Its density and pressure introduce the interaction of matter and dark energy densities in the Friedman equations. Focusing on epochs after reheating, we show that the negative dark energy tracks down the radiation energy in the radiation epoch. Such tracking dynamics ends, and dark energy becomes positive in the matter epoch. The matter converts to dark energy, and their present values are comparable, explaining the cosmic coincidence. As a result, a class of effective interacting dark energy models is advocated to confront cosmological observations.