so(4) Plebanski Action and Relativistic Spin Foam Model

TL;DR

This paper explores the connection between the so(4) Plebanski action and the relativistic spin foam model, revealing four phases including gravity and proposing a new spin foam model related to self-dual gravity.

Contribution

It establishes the continuum correspondence between the so(4) Plebanski model and the relativistic spin foam model, and introduces a new discretization linked to self-dual gravity.

Findings

The Plebanski model has four phases, including gravity.

The model exhibits a discrepancy with Euclidean gravity.

A new spin foam model related to self-dual gravity is proposed.

Abstract

In this note we study the correspondence between the ``relativistic spin foam'' model introduced by Barrett, Crane and Baez and the so(4) Plebanski action. We argue that the $so(4)$ Plebanski model is the continuum analog of the relativistic spin foam model. We prove that the Plebanski action possess four phases, one of which is gravity and outline the discrepancy between this model and the model of Euclidean gravity. We also show that the Plebanski model possess another natural dicretisation and can be associate with another, new, spin foam model that appear to be the $so(4)$ counterpart of the spin foam model describing the self dual formulation of gravity.