1999/08/05 by Sameer Gupta · 1 citation
Medicine · Physics and Astronomy · #Black Holes and Theoretical Physics #Neuroblastoma Research and Treatments #Noncommutative and Quantum Gravity Theories #gr-qc
paper · pdf · doi:10.1103/physrevd.61.064014
published as Phys.Rev. D61 (2000) 064014 · 19 pages, LaTeX2e, many eps figures
arxiv created 1999/08/05 · openalex publication_date 2000/02/24 · arxiv updated 2009/11/30 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We compute Teitelboim's causal propagator in the context of canonical loop quantum gravity. For the Lorentzian signature, we find that the resultant power series can be expressed as a sum over branched, colored two-surfaces with an intrinsic causal structure. This leads us to define a general structure which we call a ``causal spin foam.'' We also demonstrate that the causal evolution models for spin networks fall in the general class of causal spin foams.