Quantum cosmology and the value of $\Lambda$

TL;DR

This paper investigates a simple quantum cosmology model with a cosmological constant, analyzing how different boundary conditions influence the predicted value of Lambda, revealing varied results and behaviors.

Contribution

It compares the effects of different boundary conditions on the value of Lambda in quantum cosmology models, highlighting discrepancies with previous findings.

Findings

HH boundary conditions yield exp(1/Lambda) factor but are badly behaved for negative Lambda

Tunneling boundary conditions suggest a large initial Lambda

Considering only Lorentzian regions also indicates a large Lambda

Abstract

We analyse a simple model with just a $\Lambda$ term present. Differing results are obtained depending on the boundary conditions applied. HH boundary conditions give the factor exp(1/Lambda) but in agreement with Rubakov et al. is badly behaved for negative lambda. Tunneling boundary conditions suggests a large initial lambda. If only a Lorentzian region is considered all boundary conditions suggest a large value of Lambda. This differs from the result of Strominger for such models.