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Green functions and nonlinear systems: Short time expansion

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 نشر من قبل Marco Frasca
 تاريخ النشر 2007
  مجال البحث
والبحث باللغة English
 تأليف Marco Frasca




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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 field theory amounts to obtain the corresponding spectrum of the theory.



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