Bubbles of Nothing and the Fastest Decay in the Landscape

TL;DR

This paper investigates vacuum decay rates in flux compactifications, revealing how the fastest decay mode depends on the flux landscape's structure, and introduces a new instanton mediating flux tunneling and decompactification.

Contribution

It provides explicit calculations of decay rates including gravitational effects and introduces a novel instanton describing combined flux tunneling and decompactification.

Findings

Fastest decay usually involves discharging one flux unit in uniform landscapes.

In diverse flux landscapes, the fastest decay discharges all fluxes simultaneously, creating a bubble of nothing.

A new instanton mediates simultaneous flux tunneling and decompactification.

Abstract

The rate and manner of vacuum decay are calculated in an explicit flux compactification, including all thick-wall and gravitational effects. For landscapes built of many units of a single flux, the fastest decay is usually to discharge just one unit. By contrast, for landscapes built of a single unit each of many different fluxes, the fastest decay is usually to discharge all the flux at once, which destabilizes the radion and begets a bubble of nothing. By constructing the bubble of nothing as the limit in which ever more flux is removed, we gain new insight into the bubble's appearance. Finally, we describe a new instanton that mediates simultaneous flux tunneling and decompactification. Our model is the thin-brane approximation to six-dimensional Einstein-Maxwell theory.