Curvature and isocurvature perturbations in two-field inflation

@article{Lalak2007CurvatureAI,
  title={Curvature and isocurvature perturbations in two-field inflation},
  author={Zygmunt Lalak and David Langlois and Stefan Pokorski and Krzysztof Turzyński},
  journal={Journal of Cosmology and Astroparticle Physics},
  year={2007},
  volume={2007},
  pages={014 - 014}
}
We study cosmological perturbations in two-field inflation, allowing for non-standard kinetic terms. We calculate analytically the spectra of curvature and isocurvature modes at Hubble crossing, up to first order in the slow-roll parameters. We also compute numerically the evolution of the curvature and isocurvature modes from well within the Hubble radius until the end of inflation. We show explicitly for a few examples, including the recently proposed model of ‘roulette’ inflation, how… 

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