Avui, dilluns 8 de juny, el Dipòsit Digital no estarà operatiu de 15:00 a 17:00 h per tasques de manteniment. Disculpeu les molèsties.
Hoy, lunes 8 de junio, el Dipòsit Digital no estará operativo de 15:00 a 17:00 h debido a tareas de mantenimiento. Disculpen las molestias.
Today, Monday, Jun 8th, the Digital Repository will be unavailable due to a system update.

Document type

Article

Version

Published version

Publication date

All rights reserved

Please use this identifier to cite or link to this item: https://hdl.handle.net/2445/12331

Massless minimally coupled fields in de Sitter space: O(4)-symmetric states versus de Sitter invariant vacuum

Journal Title

Director/Tutor

Journal ISSN

Volume Title

Abstract

The issue of de Sitter invariance for a massless minimally coupled scalar field is examined. Formally, it is possible to construct a de Sitterinvariant state for this case provided that the zero mode of the field is quantized properly. Here we take the point of view that this state is physically acceptable, in the sense that physical observables can be computed and have a reasonable interpretation. In particular, we use this vacuum to derive a new result: that the squared difference between the field at two points along a geodesic observers spacetime path grows linearly with the observers proper time for a quantum state that does not break de Sitter invariance. Also, we use the Hadamard formalism to compute the renormalized expectation value of the energy-momentum tensor, both in the O(4)-invariant states introduced by Allen and Follaci, and in the de Sitterinvariant vacuum. We find that the vacuum energy density in the O(4)-invariant case is larger than in the de Sitterinvariant case.

Subject (English)

Citation

Citation

KIRSTEN, Klaus and GARRIGA TORRES, Jaume. Massless minimally coupled fields in de Sitter space: O(4)-symmetric states versus de Sitter invariant vacuum. Physical Review D. 1993. Vol. 48, num. 2, pags. 567-577. ISSN 0556-2821. [consulted: 9 of June of 2026]. Available at: https://hdl.handle.net/2445/12331

Export metadata

JSON - METS

Share record