3 citations · 4 across the 5 of their papers we have counts for
5 papers
(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…
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…
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…
A new 2+1 coherent spin-foam vertex for quantum gravity
José Diogo Simão
We propose an explicit spin-foam amplitude for Lorentzian gravity in three dimensions, allowing for both space- and time-like boundaries. The model is based on two main requirement…
Biquaternions, Majorana spinors and time-like spin-foams
José Diogo Simão
This work is developed in the context of Lorentzian spin-foams with space- and time-like boundaries. It is argued that the equations describing the semiclassical regime of the vari…