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arXiv · 1212.4135

Relations between canonical and non-canonical inflation

Rhiannon Gwyn·Markus Rummel·Alexander Westphal
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Abstract

We look for potential observational degeneracies between canonical and non-canonical models of inflation of a single field $ϕ$. Non-canonical inflationary models are characterized by higher than linear powers of the standard kinetic term $X$ in the effective Lagrangian $p(X,ϕ)$ and arise for instance in the context of the Dirac-Born-Infeld (DBI) action in string theory. An on-shell transformation is introduced that transforms non-canonical inflationary theories to theories with a canonical kinetic term. The 2-point function observables of the original non-canonical theory and its canonical transform are found to match in the case of DBI inflation.

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Rhiannon Gwyn, Markus Rummel, Alexander Westphal. 2014-02-27. Relations between canonical and non-canonical inflation. https://doi.org/10.1088/1475-7516%2F2013%2F12%2F010

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