The Cosmological Constant and the Deconstruction of Gravity

TL;DR

This paper explores how arguments for a zero cosmological constant in 2+1 dimensions can be extended to 3+1 dimensions, suggesting potential pathways for a consistent quantum theory of gravity.

Contribution

It demonstrates a deconstruction approach that generalizes Witten's argument from 2+1 to 3+1 dimensions, proposing a possible UV completion of gravity.

Findings

Deconstruction of 2+1D gravity arguments to 3+1D

Potential for a well-defined UV completion of gravity

Insights into the cosmological constant problem

Abstract

Witten has presented an argument for the vanishing of the cosmological constant in 2+1 dimensions. This argument is crucially tied to the specific properties of (2+1)-dimensional gravity. We argue that this reasoning can be deconstructed to 3+1 dimensions under certain conditions. Our observation is also tied to a possibility that there exists a well-defined UV completion of (3+1)-dimensional gravity.