One Loop Back Reaction On Power Law Inflation
نویسندگان
چکیده
We consider quantum mechanical corrections to a homogeneous, isotropic and spatially flat geometry whose scale factor expands classically as a general power of the co-moving time. The effects of both gravitons and the scalar inflaton are computed at one loop using the manifestly causal formalism of Schwinger [1] with the Feynman rules recently developed by Iliopoulos et al. [2]. We find no significant effect, in marked contrast with the result obtained by Mukhanov et al. [3, 4] for chaotic inflation based on a quadratic potential. By applying the canonical technique of Mukhanov et al. to the exponential potentials of power law inflation, we show that the two methods produce the same results, within the approximations employed, for these backgrounds. We therefore conclude that the shape of the inflaton potential can have an enormous impact on the one loop back-reaction. PACS numbers: 04.60.-m, 98.80.Cq ∗ Address after May 1, 1999: Theoretische Physik, Ludwig Maximilians Universität, Theresienstr. 37, D-80333 MÜNCHEN, GERMANY † e-mail: [email protected] ‡ e-mail: [email protected]
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