# q-Deformed spin foam models of quantum gravity

## TL;DR

This paper numerically investigates q-deformed Barrett-Crane spin foam models of Riemannian quantum gravity, revealing a discontinuous limit as the deformation parameter approaches 1 through roots of unity.

## Contribution

It extends numerical techniques to handle q-deformed models and arbitrary triangulations, providing new insights into their behavior and observable expectations.

## Key findings

- Discontinuous limit as q approaches 1 through roots of unity
- Computed expectation values of key observables
- Analyzed spin-spin correlation functions

## Abstract

We numerically study Barrett-Crane models of Riemannian quantum gravity. We have extended the existing numerical techniques to handle q-deformed models and arbitrary space-time triangulations. We present and interpret expectation values of a few selected observables for each model, including a spin-spin correlation function which gives insight into the behaviour of the models. We find the surprising result that, as the deformation parameter q goes to 1 through roots of unity, the limit is discontinuous.