Abstract
We examine the constraints on the construction of Fock spaces for scalar fields in spatially flat Robertson-Walker space-times imposed by requiring that the vacuum state of the theory have a two-point function possessing the Hadamard singularity structure required by standard renormalization theory. It is shown that any such vacuum state must be a second-order adiabatic vacuum. We discuss the global requirements on the two-point function for it to possess the Hadamard form at all times if it possesses it at one time.
Original language | English (US) |
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Pages (from-to) | 1942-1948 |
Number of pages | 7 |
Journal | Physical Review D |
Volume | 32 |
Issue number | 8 |
DOIs | |
State | Published - 1985 |
Externally published | Yes |
ASJC Scopus subject areas
- Physics and Astronomy (miscellaneous)