Avoiding the blue spectrum and the fine-tuning of initial conditions in hybrid inflation

@article{Clesse2008AvoidingTB,
  title={Avoiding the blue spectrum and the fine-tuning of initial conditions in hybrid inflation},
  author={S{\'e}bastien Clesse and Jonathan Rocher},
  journal={Physical Review D},
  year={2008},
  volume={79},
  pages={103507}
}
Hybrid inflation faces two well-known problems: the blue spectrum of the non-supersymmetric version of the model and the fine-tuning of the initial conditions of the fields leading to sufficient inflation to account for the standard cosmological problems. They are investigated by studying the exact two-fields dynamics instead of assuming slow-roll. When the field values are restricted to be less than the reduced Planck mass, a non-negligible part of the initial condition space (around 15… 

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