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arXiv · 1703.10141

Polynomial complexity despite the fermionic sign

R. Rossi·N. Prokof'ev·B. Svistunov·K. Van Houcke·F. Werner
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Abstract

It is commonly believed that in quantum Monte Carlo approaches to fermionic many- body problems, the infamous sign problem generically implies prohibitively large computational times for obtaining thermodynamic-limit quantities. We point out that for convergent Feynman diagrammatic series evaluated with the Monte Carlo algorithm of [Rossi, arXiv:1612.05184], the computational time increases only polynomially with the inverse error on thermodynamic-limit quantities.

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R. Rossi, N. Prokof'ev, B. Svistunov, K. Van Houcke, F. Werner. 2017-03-29. Polynomial complexity despite the fermionic sign. https://doi.org/10.1209/0295-5075%2F118%2F10004

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