GREEN FUNCTIONS AND NONLINEAR SYSTEMS: SHORT TIME EXPANSION

@article{Frasca2007GREENFA,
  title={GREEN FUNCTIONS AND NONLINEAR SYSTEMS: SHORT TIME EXPANSION},
  author={Marco Frasca},
  journal={International Journal of Modern Physics A},
  year={2007},
  volume={23},
  pages={299-308}
}
  • M. Frasca
  • Published 12 April 2007
  • Physics, Mathematics
  • International Journal of Modern Physics A
We show that Green function methods can be straightforwardly applied to nonlinear equations appearing as the leading order of a short time expansion. Higher-order corrections can be then computed giving a satisfactory agreement with numerical results. The relevance of these results relies on the possibility of fully exploiting a gradient expansion in both classical and quantum field theory granting the existence of a strong coupling expansion. Having a Green function in this regime in quantum… 

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