Environmental cosmic acceleration from a phase transition in the dark sector

TL;DR

This paper proposes a scalar tensor gravity-based mechanism that triggers a phase transition in the dark sector, leading to cosmic acceleration without a cosmological constant, and explains late-time cosmology.

Contribution

It introduces a novel degravitation mechanism within scalar tensor gravity that eliminates constant potential contributions, enabling a new explanation for cosmic acceleration.

Findings

The mechanism effectively removes constant potential terms from the Friedmann equation.

A density-triggered phase transition can produce late-time acceleration consistent with observations.

The model's parameters can be tuned to match current cosmological data.

Abstract

A new degravitation mechanism within the framework of scalar tensor gravity is postulated and included by prescription. The mechanism eliminates all constant contributions from the potential to the Friedmann equation, leaving only the kinematic and the dynamic terms of the potential to drive cosmic acceleration. We explore a scenario involving a density-triggered phase transition in the late-time universe, and argue that the resulting effective energy density and equation of state parameter can explain late-time cosmology when extrapolated to a region of the parameter space.