Cosmological Constant in LQG Vertex Amplitude

  title={Cosmological Constant in LQG Vertex Amplitude},
  author={Muxin Han},
  journal={Physical Review D},
  • Muxin Han
  • Published 11 May 2011
  • Mathematics
  • Physical Review D
A new q-deformation of the Euclidean EPRL/FK vertex amplitude is proposed by using the evaluation of the Vassiliev invariant associated with a 4-simplex graph (related to two copies of quantum SU(2) group at different roots of unity) embedded in a 3-sphere. We show that the large-j asymptotics of the q-deformed vertex amplitude gives the Regge action with a cosmological constant. In the end we also discuss its relation with a Chern-Simons theory on the boundary of 4-simplex. 

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