Nonequilibrium Dynamics of Quantum Fields in Inflationary Cosmology

  title={Nonequilibrium Dynamics of Quantum Fields in Inflationary Cosmology},
  author={Stephen A. Ramsey},
  journal={International Journal of Theoretical Physics},
  • S. Ramsey
  • Published 1 April 1999
  • Physics
  • International Journal of Theoretical Physics
We summarize a recent study (with B. L. Hu) ofthe nonequilibrium dynamics of an unbroken-symmetryinflaton field during postinflationary reheating, duringwhich the energy density contained in the expectation value of the inflaton field is rapidlytransferred to inhomogeneous quantum modes of theinflaton field. The coupled dynamics of the expectationvalue (mean field) of a scalar inflaton field with anunbroken global O(N) symmetry and its quantum varianceis studied using the leading-order, large… 
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