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arXiv · 0804.4291

Effective Field Theory for Inflation

Steven Weinberg
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Abstract

The methods of effective field theory are used to study generic theories of inflation with a single inflaton field. For scalar modes, the leading corrections to the ${\cal R}$ correlation function are found to be purely of the $k$-inflation type. For tensor modes the leading corrections to the correlation function arise from terms in the action that are quadratic in the curvature, including a parity-violating term that makes the propagation of these modes depend on their helicity. These methods are also briefly applied to non-generic theories of inflation with an extra shift symmetry, as in so-called ghost inflation.

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Steven Weinberg. 2008-05-15. Effective Field Theory for Inflation. https://doi.org/10.1103/physrevd.77.123541

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