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arXiv · 0704.1568

Green functions and nonlinear systems: Short time expansion

Marco Frasca
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Abstract

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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Marco Frasca. 2007-10-02. Green functions and nonlinear systems: Short time expansion. https://doi.org/10.1142/s0217751x08038160

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