Nonlinear superhorizon curvature perturbation in generic single-field inflation

@article{Takamizu2013NonlinearSC,
  title={Nonlinear superhorizon curvature perturbation in generic single-field inflation},
  author={Yu-ichi Takamizu and Tsutomu Kobayashi},
  journal={Progress of Theoretical and Experimental Physics},
  year={2013},
  volume={2013}
}
is more general than k-inflation, and is called G-inflation. A general nonlinear solution for the metric and the scalar field is obtained at second order in gradient expansion. We derive a simple master equation governing the large-scale evolution of the nonlinear curvature perturbation. It turns out that the nonlinear evolution equation is deduced as a straightforward extension of the corresponding linear equation for the curvature perturbation on uniform φ hypersurfaces. 
8 Citations

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  • 2013

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