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arXiv · 0704.0278

q-Deformed spin foam models of quantum gravity

Igor Khavkine·J. Daniel Christensen
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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.

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Igor Khavkine, J. Daniel Christensen. 2007-04-02. q-Deformed spin foam models of quantum gravity. https://doi.org/10.1088/0264-9381%2F24%2F13%2F009

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