Hadamard states and adiabatic vacua.
نویسنده
چکیده
A proof is presented that in a spatially flat Robertson-Walker spacetime the adia-batic vacuum of scalar quantum field is a Hadamard state only if it is of infinite order and vice versa every Hadamard state lies in the Fock space based on an adiabatic vacuum.
منابع مشابه
3 v 1 2 1 A ug 1 99 8 Not all adiabatic vacua are physical states
Adiabatic vacua are known to be Hadamard states. We show, however that the energy-momentum tensor of a linear Klein-Gordon field on Robertson-Walker spaces developes a generic singularity on the initial hypersurface if the adiabatic vacuum is of order less than four. Therefore, adiabatic vacua are physically reasonable only if their order is at least four. A certain non-local large momentum exp...
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Adiabatic vacua are known to be Hadamard states. We show, however that the energy-momentum tensor of a linear Klein-Gordon eld on Robertson-Walker spaces developes a generic singularity on the initial hypersurface if the adiabatic vacuum is of order less than four. Therefore, adiabatic vacua are physically reasonable only if their order is at least four. A certain non-local large momentum expan...
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عنوان ژورنال:
- Physical review. D, Particles and fields
دوره 48 8 شماره
صفحات -
تاریخ انتشار 1993