2 papers
gr-qc2025
On quantum creation of a toroidal universe
Alan H. Guth, Alexander Vilenkin
We consider the quantum creation of a universe with flat spatial sections and the topology of a 3-torus, taking into account the effect of Casimir energy. We show that the correspo…
gr-qc2024
Global String Instantons
Jose J. Blanco-Pillado, Georgios Fanaras, Alexander Vilenkin
We study the formation of gravitating global strings through quantum mechanical tunneling. The instantons that describe the nucleation process are characterized by two parameters:…