A toy model based analysis on the effect of the Lee-Wick partners in the evolution of the early universe

TL;DR

This paper explores how Lee-Wick partners influence early universe evolution using a simplified toy model, revealing potential deviations from standard cosmology and conditions for transition to the conventional universe.

Contribution

It introduces a toy model incorporating Lee-Wick partners to analyze early universe thermodynamics and evolution, highlighting challenges and possible pathways to standard cosmology.

Findings

Analytical time-temperature relation in early universe with Lee-Wick partners.

Conditions under which Lee-Wick dominated universe transitions to standard cosmology.

Potential for negative energy densities in Lee-Wick extended models.

Abstract

In the present article the thermodynamic results of the Lee-Wick partner infested universe have been applied in a toy model where there is one Lee-Wick partner to each of the standard model particle and more over the longitudinal degrees of freedom of the massive partners of the standard massless gauge bosons are neglected at high temperatures. For practical purposes, the chiral fermionic sector of Lee-wick theories requires two Lee-Wick partners per fermion which opens up the possibility for a negative energy density of the early universe. A toy Lee-Wick model with one fermionic partner relaxes such oddities and hence easy to deal with. In a similar way, the longitudinal degrees of freedom of the massive gauge boson partners also have the potential to yield negative energy densities and thus those will be neglected in a toy model study. In such a toy model one can analytically calculate the time-temperature relation in the very early radiation dominated universe which shows interesting new physics. The article also tries to point out how a Lee-Wick particle dominated early cosmology transforms into the standard cosmological model. Based on the results of this toy model analysis a brief discussion on the more realistic model, which can accommodate two Lee-Wick partners for each standard fermionic field and the longitudinal degree of freedom of partners of the gauge fields, is presented. It has been shown that such an universe is mostly very difficult to attain but there are certain conditions where one can indeed think of such an universe which can evolve into the standard cosmological universe in a short time duration.