# Critical Number of Fields in Stochastic Inflation.

@article{Vennin2017CriticalNO, title={Critical Number of Fields in Stochastic Inflation.}, author={Vincent Vennin and Hooshyar Assadullahi and Hassan Firouzjahi and Mahdiyar Noorbala and David Wands}, journal={Physical review letters}, year={2017}, volume={118 3}, pages={ 031301 } }

Stochastic effects in generic scenarios of inflation with multiple fields are investigated. First passage time techniques are employed to calculate the statistical moments of the number of inflationary e-folds, which give rise to all correlation functions of primordial curvature perturbations through the stochastic δN formalism. The number of fields is a critical parameter. The probability of exploring arbitrarily large-field regions of the potential becomes nonvanishing when more than two…

## 45 Citations

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Abstract
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