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arXiv · hep-ph/0104083

Curvature perturbation at the local extremum of the inflaton's potential

Jun'ichi Yokoyama·Shogo Inoue
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Abstract

The spectrum of curvature perturbation generated during inflation is studied in the case the inflation-driving scalar field (inflaton) $ϕ$ crosses over its potential extremum. It is shown that the nondecaying mode of perturbation has a finite value and a proper formula is given. The result is also extended to more general cases where $\ddotϕ$ is non-negligible.

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Jun'ichi Yokoyama, Shogo Inoue. 2001-11-29. Curvature perturbation at the local extremum of the inflaton's potential. https://doi.org/10.1016/s0370-2693(01)01369-7

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