Dynamical evolution of the Universe in the quark-hadron phase transition and possible nugget formation

TL;DR

This paper investigates the early Universe's first-order quark-hadron phase transition, focusing on nucleation, supercooling, and the potential formation and survival of quark nuggets as dark matter candidates.

Contribution

It provides a detailed analysis of phase transition dynamics, including nucleation scales and conditions for quark nugget formation and survival, linking to dark matter observations.

Findings

Estimates of nucleation scales and hadron fraction during transition

Conditions under which quark nuggets can survive

Potential connection between quark nuggets and dark matter objects

Abstract

We study the dynamics of first-order phase transition in the early Universe when it was $10-50 \mu s$ old with quarks and gluons condensing into hadrons. We look at how the Universe evolved through the phase transition in small as well as large super cooling scenario, specifically exploring the formation of quark nuggets and their possible survival. The nucleation of the hadron phase introduces new distance scales in the Universe, which we estimate along with the hadron fraction, temperature, nucleation time etc. It is of interest to explore whether there is a relic signature of this transition in the form of quark nuggets which might be identified with the recently observed dark objects in our galactic halo and account for the Dark Matter in the Universe at present.