Quantum Fields in a Big Crunch/Big Bang Spacetime
نویسندگان
چکیده
We consider quantum field theory on a spacetime representing the Big Crunch/Big Bang transition postulated in ekpyrotic or cyclic cosmologies. We show via several independent methods that an essentially unique matching rule holds connecting the incoming state, in which a single extra dimension shrinks to zero, to the outgoing state in which it re-expands at the same rate. For free fields in our construction there is no particle production from the incoming adiabatic vacuum. When interactions are included the particle production for fixed external momentum is finite at tree level. We discuss a formal correspondence between our construction and quantum field theory on de Sitter spacetime. Typeset using REVTEX
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