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arXiv · 1108.6059

2-point functions in quantum cosmology

Steffen Gielen
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Abstract

We discuss the path-integral formulation of quantum cosmology with a massless scalar field as a sum-over-histories, with particular reference to loop quantum cosmology. Exploiting the analogy with the relativistic particle, we give a complete overview of the possible two-point functions, deriving vertex expansions and composition laws they satisfy. We clarify the tie between definitions using a group averaging procedure and those in a deparametrised framework. We draw some conclusions about the physics of a single quantum universe and multiverse field theories where the role of these sectors and the inner product are reinterpreted.

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Steffen Gielen. 2011-08-30. 2-point functions in quantum cosmology. https://doi.org/10.1088/1742-6596/360/1/012029

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