The Plebanski sectors of the EPRL vertex

作者：Engle Jonathan^*

来源：Classical and Quantum Gravity, 2011, 28(22): 225003.

DOI：10.1088/0264-9381/28/22/225003

Modern spin-foam models of four-dimensional gravity are based on a discrete version of the Spin(4) Plebanski formulation. Beyond what is already in the literature, we clarify the meaning of different Plebanski sectors in this classical discrete model. We show that the linearized simplicity constraint used in the EPRL and FK models are not sufficient to impose a restriction to a single Plebanski sector, but rather, three Plebanski sectors are mixed. We propose this as the reason for certain extra 'undesired' terms in the asymptotics of the EPRL vertex analyzed by Barrett et al. This explanation for the extra terms is new and different from that sometimes offered in the spin-foam literature thus far.

• 出版日期2011-11-21