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arXiv · 1111.3040

A Field Range Bound for General Single-Field Inflation

Daniel Baumann·Daniel Green
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Abstract

We explore the consequences of a detection of primordial tensor fluctuations for general single-field models of inflation. Using the effective theory of inflation, we propose a generalization of the Lyth bound. Our bound applies to all single-field models with two-derivative kinetic terms for the scalar fluctuations and is always stronger than the corresponding bound for slow-roll models. This shows that non-trivial dynamics can't evade the Lyth bound. We also present a weaker, but completely universal bound that holds whenever the Null Energy Condition (NEC) is satisfied at horizon crossing.

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Daniel Baumann, Daniel Green. 2011-11-13. A Field Range Bound for General Single-Field Inflation. https://doi.org/10.1088/1475-7516%2F2012%2F05%2F017

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