# New Kaluza-Klein Instantons and Decay of AdS Vacua

## TL;DR

This paper generalizes Witten's Kaluza-Klein instanton to higher dimensions, demonstrating that certain non-supersymmetric AdS_5 vacua in M theory are unstable due to bubble of nothing solutions, supporting conjectures about their inherent instability.

## Contribution

It introduces a new class of Kaluza-Klein instantons involving higher-dimensional spheres, extending the understanding of vacuum decay in M theory.

## Key findings

- Non-supersymmetric AdS_5 vacua are unstable due to bubble of nothing solutions.
- The instanton involves a higher-dimensional sphere collapsing to zero size.
- Supports the conjecture that all non-supersymmetric flux-supported AdS vacua are unstable.

## Abstract

We construct a generalization of Witten's Kaluza-Klein instanton, where a higher-dimensional sphere (rather than a circle as in Witten's instanton) collapses to zero size and the geometry terminates at a bubble of nothing, in a low energy effective theory of M theory. We use the solution to exhibit instability of non-supersymmetric AdS_5 vacua in M Theory compactified on positive Kaehler-Einstein spaces, providing a further evidence for the recent conjecture that any non-supersymmetric anti-de Sitter vacuum supported by fluxes must be unstable.