# The WKB approximation and tunneling in theories with non-canonical kinetic terms

## TL;DR

This paper develops a detailed theoretical framework for calculating quantum tunneling rates in theories with non-canonical kinetic terms, extending the understanding of metastability and early universe phenomena beyond traditional models.

## Contribution

It introduces a rigorous method for analyzing tunneling in non-canonical kinetic theories, filling a gap in the existing quantum mechanics and cosmology literature.

## Key findings

- Framework successfully applied to multiple examples
- Provides new insights into tunneling in non-canonical theories
- Enhances understanding of metastability in early universe models

## Abstract

Tunneling is a fascinating aspect of quantum mechanics that renders the local minima of a potential meta-stable, with important consequences for particle physics, for the early hot stage of the universe, and more speculatively, for the behavior of the putative multiverse. While this phenomenon has been studied extensively for systems which have canonical kinetic terms, many theories of fundamental physics contain fields with non-canonical kinetic structures. It is therefore desirable to have a detailed framework for calculating tunneling rates and initial states after tunneling for these theories. In this work, we present such a rigorous formulation and illustrate its use by applying it to a number of examples.