Discrete Gravity Models and Loop Quantum Gravity: a Short Review

SIGMA 04/2012; DOI:10.3842/SIGMA.2012.052
Source: arXiv

ABSTRACT We review the relation between Loop Quantum Gravity on a fixed graph and
discrete models of gravity. We compare Regge and twisted geometries, and
discuss discrete actions based on twisted geometries and on the discretization
of the Plebanski action. We discuss the role of discrete geometries in the spin
foam formalism, with particular attention to the definition of the simplicity

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