Properties of the transition matrix in bouncing cosmologies
نویسندگان
چکیده
منابع مشابه
On the "Causality argument" in bouncing cosmologies.
We exhibit a situation in which cosmological perturbations of astrophysical relevance propagating through a bounce are affected in a scale-dependent way. Involving only the evolution of a scalar field in a closed universe described by general relativity, the model is consistent with causality. Such a specific counterexample leads to the conclusion that imposing causality is not sufficient to de...
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Hèlios Sanchis-Alepuz Departamento de Fı́sica Teórica and IFIC, Centro Mixto Universidad de Valencia-CSIC. Facultad de Fı́sica, Universidad de Valencia, Burjassot-46100, Valencia, Spain and Fachbereich Theoretische Physik, Institut für Physik, Karl-Franzens-Universität Graz, Universitätsplatz 5, A-8010 Graz, Austria (Received 12 June 2009; published 16 July 2009) We consider the early time cosmol...
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ژورنال
عنوان ژورنال: Physical Review D
سال: 2004
ISSN: 1550-7998,1550-2368
DOI: 10.1103/physrevd.69.107301