Degravitation of the Cosmological Constant and Graviton Width

TL;DR

This paper explores a mechanism to decouple gravity from vacuum energy by modifying Newton's constant into a high-pass filter, analyzing its physical consistency and implications for graviton properties.

Contribution

It introduces a framework where gravity's coupling to vacuum energy is suppressed at large scales, linking this to graviton mass or resonance width, and examines the theory's consistency.

Findings

Decoupling gravity from vacuum energy is feasible with a high-pass filter approach.

Graviton must be either massive with scale 1/L or a resonance of similar width.

The theory's consistency requires absence of ghosts at the linear level.

Abstract

We study the possibility of decoupling gravity from the vacuum energy. This is effectively equivalent to promoting Newton's constant to a high-pass filter that degravitates sources of characteristic wavelength larger than a certain macroscopic (super) horizon scale L. We study the underlying physics and the consistency of this phenomenon. In particular, the absence of ghosts, already at the linear level, implies that in any such theory the graviton should either have a mass 1/L, or be a resonance of similar width. This has profound physical implications for the degravitation idea.