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arXiv · 0706.4359

Existence of positive representations for complex weights

L. L. Salcedo
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Abstract

The necessity of computing integrals with complex weights over manifolds with a large number of dimensions, e.g., in some field theoretical settings, poses a problem for the use of Monte Carlo techniques. Here it is shown that very general complex weight functions P(x) on R^d can be represented by real and positive weights p(z) on C^d, in the sense that for any observable f, _P = _p, f(z) being the analytical extension of f(x). The construction is extended to arbitrary compact Lie groups.

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L. L. Salcedo. 2007-06-29. Existence of positive representations for complex weights. https://doi.org/10.1088/1751-8113%2F40%2F31%2F016

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