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arXiv · 0802.1972

The quantum theory of scalar fields on the de Sitter expanding universe

Ion I. Cotaescu·Cosmin Crucean·Adrian Pop
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Abstract

New quantum modes of the free scalar field are derived in a special time-evolution picture that may be introduced in moving charts of de Sitter backgrounds. The wave functions of these new modes are solutions of the Klein-Gordon equation and energy eigenfunctions, defining the energy basis. This completes the scalar quantum mechanics where the momentum basis is well-known from long time. In this enlarged framework the quantization of the scalar field can be done in canonical way obtaining the principal conserved one-particle operators and the Green functions.

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Ion I. Cotaescu, Cosmin Crucean, Adrian Pop. 2008-02-14. The quantum theory of scalar fields on the de Sitter expanding universe. https://doi.org/10.1142/s0217751x08040494

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