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arXiv · 1701.02680

A stochastic root finding approach: The Homotopy Analysis Method applied to Dyson-Schwinger Equations

Tobias Pfeffer·Lode Pollet
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Abstract

We present the construction and stochastic summation of rooted-tree diagrams, based on the expansion of a root finding algorithm applied to the Dyson-Schwinger equations (DSEs). The mathematical formulation shows superior convergence properties compared to the bold diagrammatic Monte Carlo approach and the developed algorithm allows one to tackle generic high-dimensional integral equations, to avoid the curse of dealing explicitly with high-dimensional objects and to access non-perturbative regimes. The sign problem remains the limiting factor, but it is not found to be worse than in other approaches. We illustrate the method for $\phi^4$ theory but note that it applies in principle to any model.

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BibTeXRIS

Tobias Pfeffer, Lode Pollet. 2017-01-10. A stochastic root finding approach: The Homotopy Analysis Method applied to Dyson-Schwinger Equations. https://doi.org/10.1088/1367-2630/aa631f

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