On the spinfoam expansion in cosmology

Carlo Rovelli (1) , Francesca Vidotto (1, 2)

1 HCTLab - Human Computer Technology Laboratory
2 Dipartimento di Fisica Nucleare e Teorica

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 ".

Mots clés: Physical Sciences

Carlo Rovelli, Francesca Vidotto. On the spinfoam expansion in cosmology. Classical and Quantum Gravity, 2010, 27 (14), pp.145005. ⟨10.1088/0264-9381/27/14/145005⟩. ⟨hal-00610061⟩