Solution to the Cosmological Constant Problem in a Regge Quantum Gravity Model

TL;DR

This paper proposes a solution to the cosmological constant problem within a Regge quantum gravity framework by adjusting a free parameter in the path-integral measure to match observed values.

Contribution

It introduces a novel approach using the effective action and a special measure in Regge calculus to naturally cancel the cosmological constant.

Findings

The effective cosmological constant can be tuned to match observations.

The classical and matter cosmological constants are balanced to isolate the quantum gravity contribution.

A free parameter in the measure allows for the observed small value of the cosmological constant.

Abstract

We show that it is possible to solve the cosmological constant (CC) problem in a discrete quantum gravity theory based on Regge calculus by using the effective action approach and a special path-integral measure. The effective cosmological constant is given as a sum of 3 terms: the classical CC, the quantum gravity CC and the matter CC. Since the observations can only measure the sum of these 3 terms, we can choose the classical CC to be equal to the negative value of the matter CC. Hence the effective CC is given only by the quantum gravity CC, which is determined by the path-integral measure. Since the path-integral measure depends on a free parameter, this parameter can be chosen such that the effective CC gives the observed value.