Four-dimensional spinfoam quantum gravity with a cosmological constant: Finiteness and semiclassical limit

  title={Four-dimensional spinfoam quantum gravity with a cosmological constant: Finiteness and semiclassical limit},
  author={Muxin Han},
  journal={Physical Review D},
  • Muxin Han
  • Published 31 August 2021
  • Physics, Mathematics
  • Physical Review D
We present an improved formulation of 4-dimensional Lorentzian spinfoam quantum gravity with cosmological constant. The construction of spinfoam amplitudes uses the state-integral model of PSL(2,C) Chern-Simons theory and the implementation of simplicity constraint. The formulation has 2 key features: (1) spinfoam amplitudes are all finite, and (2) With suitable boundary data, the semiclassical asymptotics of the vertex amplitude has two oscillatory terms, with phase plus or minus the 4… 
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