Lorentzian Vacuum Transitions with a Generalized Uncertainty Principle

TL;DR

This paper develops a semi-classical method to compute vacuum transition probabilities in cosmological models, incorporating a Generalized Uncertainty Principle, and analyzes how it affects transition likelihoods in various metrics.

Contribution

It introduces a generalized approach to calculate vacuum transition probabilities using the Wheeler-DeWitt equation with GUP effects in different cosmological models.

Findings

GUP enhances initial transition probabilities but causes faster decay at larger scales.

Anisotropy influences transition probabilities compared to isotropic models.

Transition probabilities vary significantly when GUP is considered, affecting cosmological evolution.

Abstract

The vacuum transition probabilities between to minima of a scalar field potential in the presence of gravity are studied using the Wentzel-Kramers-Brillouin approximation. First we propose a method to compute these transition probabilities by solving the Wheeler-DeWitt equation in a semi-classical approach for any model of superspace that contains terms of squared as well as linear momenta in the Hamiltonian constraint generalizing in this way previous results. Then we apply this method to compute the transition probabilities for a Friedmann-Lemaitre-Robertson-Walker metric with positive and null curvature and for the Bianchi III metric when the coordinates of minisuperspace obey a Standard Uncertainty Principle and when a Generalized Uncertainty Principle is taken into account. In all cases we compare the results and found that the effect of considering a Generalized Uncertainty Principle is that the probability is enhanced at first but it decays faster so when the corresponding scale factor is big enough the probability is reduced. We also consider the effect of anisotropy and compare the result of the Bianchi III metric with the flat FLRW metric which corresponds to its isotropy limit and comment the differences with previous works.