Initial time singularities and admissible initial states for a system of coupled scalar fields
| Autor: | Jürgen Baacke, Nina Kevlishvili |
|---|---|
| Rok vydání: | 2010 |
| Předmět: |
High Energy Physics - Theory
Physics Nuclear and High Energy Physics Scalar (mathematics) FOS: Physical sciences General Relativity and Quantum Cosmology (gr-qc) General Relativity and Quantum Cosmology Fock space Bogoliubov transformation Classical mechanics High Energy Physics - Theory (hep-th) Stress–energy tensor ddc:530 Gravitational singularity Ground state Adiabatic process Quantum fluctuation |
| Zdroj: | Red Report (2009). Physical review / D 81(2), 023509 (2010). doi:10.1103/PhysRevD.81.023509 |
| ISSN: | 1550-2368 1550-7998 |
| DOI: | 10.1103/physrevd.81.023509 |
| Popis: | We discuss the problem of initial states for a system of coupled scalar fields out of equilibrium in the one-loop approximation. The fields consist of classical background fields, taken constant in space, and quantum fluctuations. If the initial state is the adiabatic vacuum, i.e., the ground state of a Fock space of particle excitations that diagonalize the mass matrix, the energy-momentum tensor is infinite at t=0, its most singular part behaves as 1/t. When the system is coupled to gravity this presents a problem that we solve by a Bogoliubov transformation of the naive initial state. As a side result we also discuss the canonical formalism and the adiabatic particle number for such a system. Most of the formalism is presented for Minkowksi space. Embedding the system and its dynamics into a flat FRW universe is straightforward and we briefly address the essential modifications. Comment: 26 pages, no figures; typos corrected, added 6 paragraphs et the end of section 3, and 1 paragraph at the end of section 5 |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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