A graviton propagator for inflation
نویسندگان
چکیده
We construct the scalar and graviton propagator in quasi de Sitter space up to first order in the slow roll parameter ǫ ≡ −Ḣ/H2. After a rescaling, the propagators are similar to those in de Sitter space with an ǫ correction to the effective mass. The limit ǫ → 0 corresponds to the E(3) vacuum that breaks de Sitter symmetry, but does not break spatial isotropy and homogeneity. The new propagators allow for a self-consistent, dynamical study of quantum back-reaction effects during inflation.
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