Numerical Evaluation of Tunneling Probabilities for the Birth of Universes with Radiation, Cosmological Constant, and Ad-hoc Potential

Oliveira-Neto et al. (Eur. Phys. J. Plus 138, 400 2023) recently investigated the birth of Friedmann-Lema & iuml;tre-Robertson-Walker (FLRW) universes with flat (k=0\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$k=0$$\end{document}) and hyperbolic (k=-1\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$k=-1$$\end{document}) curvatures of their spatial sections, with material contents composed of radiation, a positive cosmological constant and an ad-hoc potential, solving the Wheeler-DeWitt equation and calculating tunneling probabilities for the birth of those universes as functions not only of the wave packet energy, but also of the system parameters, via the semi-classical WKB approximation. In this article we review that analysis using a more general and accurate numerical method for calculating tunneling probabilities. Larger probabilities than those obtained by the WKB approximation have been obtained for the birth of such universes.