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arXiv · 0911.3097

On the spinfoam expansion in cosmology

Carlo Rovelli·Francesca Vidotto
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Abstract

We consider the technique introduced in a recent work by Ashtekar, Campiglia and Henderson, which generate a spinfoam-like sum from a Hamiltonian theory. We study the possibility of using it for finding the generalized projector of a constraint on physical states, without first deparametrising the system. We illustrate this technique in the context of a very simple example. We discuss the infinities that appear in the calculation, and argue that they can be appropriately controlled. We apply these ideas to write a spinfoam expansion for the "dipole cosmology".

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Carlo Rovelli, Francesca Vidotto. 2010-02-17. On the spinfoam expansion in cosmology. https://doi.org/10.1088/0264-9381%2F27%2F14%2F145005

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