Moment transport equations for the primordial curvature perturbation

@article{Mulryne2011MomentTE,
  title={Moment transport equations for the primordial curvature perturbation},
  author={David J. Mulryne and D avid Seery and Daniel H. Wesley},
  journal={Journal of Cosmology and Astroparticle Physics},
  year={2011},
  volume={2011},
  pages={030-030}
}
In a recent publication, we proposed that inflationary perturbation theory can be reformulated in terms of a probability transport equation, whose moments determine the correlation properties of the primordial curvature perturbation. In this paper we generalize this formulation to an arbitrary number of fields. We deduce ordinary differential equations for the evolution of the moments of ζ on superhorizon scales, which can be used to obtain an evolution equation for the dimensionless bispectrum… 

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