Göttingen 2012 – scientific programme

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GR: Fachverband Gravitation und Relativitätstheorie

GR 15: Quantengravitation und Quantenkosmologie II

GR 15.2: Talk

Thursday, March 1, 2012, 17:05–17:25, ZHG 002

Decoherence in loop quantum cosmology with fermions — Claus Kiefer and •Christian Schell — Institut für Theoretische Physik, Universität zu Köln

Loop quantum cosmology employs triads of two different orientations. The theory allows them to occur in an arbitrary superposition. Here we show how such a superposition is rendered unobservable by decoherence - the irreversible interaction with an ``environment". Since a suitable environment must be able to distinguish between the two orientations, we introduce fermions for its description. Solving the total difference equation numerically and integrating out the fermions, we obtain the reduced density matrix for the triads. We discuss the degree of decoherence described by it and focus on the relevance of our results for interpretational issues in loop quantum cosmology.