# 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} }

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…

## 19 Citations

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