3 papers
gr-qc2025
(2+1) Lorentzian quantum cosmology from spin-foams: opportunities and obstacles for semi-classicality
Alexander F. Jercher, José Diogo Simão, Sebastian Steinhaus
We construct an effective cosmological spin-foam model for a (2+1) dimensional spatially flat universe, discretized on a hypercubical lattice, containing both space- and time-like…
gr-qc2024
Investigations on Lorentzian Spin-foams and Semiclassical Space-times
José Diogo Simão
This thesis is developed in the context of the spin-foam approach to quantum gravity; all results are concerned with the Lorentzian theory and with semiclassical methods. A corresp…
gr-qc2024
Partial absence of cosine problem in 3d Lorentzian spin foams
Alexander F. Jercher, José Diogo Simão, Sebastian Steinhaus
We study the semi-classical limit of the recently proposed coherent spin foam model for (2+1) Lorentzian quantum gravity. Specifically, we analyze the gluing equations derived from…