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arXiv · 2601.17453

Nested ansatz method for Baker-Akhiezer functions

A. Mironov·A. Morozov·A. Popolitov
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Abstract

We explain that the logic behind the derivation of the Noumi-Shiraishi function can be applied directly to the Baker-Akhiezer function (BAF). This amounts to changing an ansatz for BAF to a nested one, where the BAF of N + 1 variables is recursively expressed as a sum over BAFs of N variables. This may be seen as a generalization of symmetrization trick from [1], but for the generally non-symmetric BAF. We demonstrate that, for usual non-twisted (a = 1) BAFs, this method correctly reproduces the Noumi-Shiraishi formula directly from linear equations, resolving the ambiguity related to non-simple roots. For the first non-trivial twisted case (N = 3, a = 2) this method also fixes this ambiguity, moreover, answers for the first few layers of coefficients are in the form of direct quantization of [1].

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A. Mironov, A. Morozov, A. Popolitov. 2026-01-24. Nested ansatz method for Baker-Akhiezer functions. https://arxiv.org/abs/2601.17453

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