Axion Flux Monodromy Discharges Relax the Cosmological Constant

TL;DR

This paper proposes a model using axion monodromy with flux discharges to naturally relax the cosmological constant to a small, finite value consistent with dark energy observations.

Contribution

It introduces a flux discharge mechanism within axion monodromy models that can dynamically reduce the cosmological constant to a tiny, finite value, aligning with observed dark energy scale.

Findings

The mechanism relaxes the cosmological constant toward a small attractor value.

Finite flux range leads to a tiny but non-zero cosmological constant.

The model can incorporate matter sector phase transitions.

Abstract

Linear axion monodromy models modulated with higher powers of fields naturally realize the quantum-mechanical flux discharge mechanism for relaxing the cosmological constant toward zero. Working with multiple copies of superposed linear and quadratic flux monodromies, each copy spanned by a pair of fluxes, we show that when the axion is very massive and so effectively decoupled, the membrane discharges relax the cosmological constant toward an attractor $0 < \Lambda/\mpl^4 \ll 1$. If we restrict the flux variations and the intermediate flux values to never venture beyond a finite flux range, the terminal value of the cosmological constant will be tiny but finite. We show how it can reproduce the observed scale of dark energy, and explain how to incorporate matter sector phase transitions.