The Running of the Cosmological and the Newton Constant controlled by the Cosmological Event Horizon

TL;DR

This paper investigates how the cosmological and Newton constants evolve with the universe's horizon size, revealing stable de Sitter states and potential catastrophic futures like big crunches or big rips.

Contribution

It introduces a novel approach linking the renormalisation scale to the cosmological event horizon, analyzing its impact on universe evolution and stability.

Findings

Stable de Sitter solutions identified

Possible big crunch and big rip scenarios

Dependence of outcomes on model parameters

Abstract

We study the renormalisation group running of the cosmological and the Newton constant, where the renormalisation scale is given by the inverse of the radius of the cosmological event horizon. In this framework, we discuss the future evolution of the universe, where we find stable de Sitter solutions, but also "big crunch"-like and "big rip"-like events, depending on the choice of the parameters in the model.