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DOE OSTI · 2420020

Noise effects on Padé approximants and conformal maps

Costin, Ovidiu·Dunne, Gerald V.·Meynig, Max
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Abstract

Here, we analyze the properties of Padé and conformal map approximants for functions with branch points, in the situation where the expansion coefficients are only known with finite precision or are subject to noise. We prove that there is a universal scaling relation between the strength of the noise and the expansion order at which Padé or the conformal map breaks down. We illustrate this behavior with some physically relevant model test functions and with two non-trivial physical examples where the relevant Riemann surface has complicated structure.

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97 MATHEMATICS AND COMPUTINGPade approximantsPainleveconformal mapsnoisequantum field theory

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Costin, Ovidiu, Dunne, Gerald V., Meynig, Max. 2022-11-25. Noise effects on Padé approximants and conformal maps. https://doi.org/10.1088/1751-8121%2Faca303

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