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arXiv · 1010.0502

Local spinfoam expansion in loop quantum cosmology

Adam Henderson·Carlo Rovelli·Francesca Vidotto·Edward Wilson-Ewing
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Abstract

The quantum dynamics of the flat Friedmann-Lemaitre-Robertson-Walker and Bianchi I models defined by loop quantum cosmology have recently been translated into a spinfoam-like formalism. The construction is facilitated by the presence of a massless scalar field which is used as an internal clock. The implicit integration over the matter variable leads to a nonlocal spinfoam amplitude. In this paper we consider a vacuum Bianchi I universe and show that by choosing an appropriate regulator a spinfoam expansion can be obtained without selecting a clock variable and that the resulting spinfoam amplitude is local.

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Adam Henderson, Carlo Rovelli, Francesca Vidotto, Edward Wilson-Ewing. 2010-11-19. Local spinfoam expansion in loop quantum cosmology. https://doi.org/10.1088/0264-9381%2F28%2F2%2F025003

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