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arXiv · 2510.12136

Nevanlinna-Pick interpolation from uncertain data

Sarah Fields·Norman Christ
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Abstract

The calculation of inclusive processes that involve the production of many particles is a challenge for lattice QCD, a Euclidean-space method that is far removed from real-time, multiparticle production. A new approach to this problem based on Nevanlinna-Pick interpolation has been proposed by Bergamaschi et al. Here we extend their method by exploring the propagation of the statistical and systematic errors that accompany a lattice QCD calculation through this interpolation process. A simplified example of a multiparticle spectral function is studied with a focus on the possible applications of these methods to the calculation of inclusive heavy-particle decays.

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Sarah Fields, Norman Christ. 2025-10-14. Nevanlinna-Pick interpolation from uncertain data. https://doi.org/10.1103/brwx-k3xf

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