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arXiv · 1007.3723

Vertex Expansion for the Bianchi I model

Miguel Campiglia·Adam Henderson·William Nelson
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Abstract

A perturbative expansion of Loop Quantum Cosmological transitions amplitudes of Bianchi I models is performed. Following the procedure outlined in [1,2] for isotropic models, it is shown that the resulting expansion can be written in the form of a series of amplitudes each with a fixed number of transitions mimicking a spin foam expansion. This analogy is more complete than in the isotropic case, since there are now the additional anisotropic degrees of freedom which play the role of `colouring' of the spin foams. Furthermore, the isotropic expansion is recovered by integrating out the anisotropies.

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Miguel Campiglia, Adam Henderson, William Nelson. 2010-07-21. Vertex Expansion for the Bianchi I model. https://doi.org/10.1103/physrevd.82.064036

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