Quantum models of space-time based on recoupling theory

Thesis

Models of geometry that are intrinsically quantum-mechanical in nature arise from the recoupling theory of space-time symmetry groups. Roger Penrose constructed such a model from SU(2) recoupling in his theory of spin networks; he showed that spin measurements in a classical limit are necessarily consistent with a three-dimensional Euclidian vector space. T. Regge and G. Ponzano expressed the semi-classical limit of this spin model in a form resembling a path integral of the Einstein-Hilbert action in three Euclidian dimensions. This thesis gives new proofs of the Penrose spin geometry theorem and of the Regge-Ponzano decomposition theorem. We then consider how to generalize these two approaches to other groups that give rise to new models of quantum geometries. In particular, we show how to construct quantum models of four-dimensional relativistic space-time from the re-coupling theory of the Poincare group.

Authors: Moussouris, J

• Publication date: 1984
• Type of award: DPhil
• Level of award: Doctoral
• Awarding institution: University of Oxford
• Language: English
• Keywords: penrose; racah; spin networks; quantum; relativity; groups; geometry; poincare group; regge; ponzano; recoupling
• Subjects: Quantum theory (mathematics); Geometry; Combinatorics; Theoretical physics; Group theory and generalizations (mathematics); Mechanics of particles and systems (mathematics)