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JOURNALS // Matematicheskii Sbornik // Archive

Mat. Sb., 2025 Volume 216, Number 12, Pages 125–144 (Mi sm10349)

Inversion of the Abel–Prym map in presence of an additional involution

O. K. Sheinman

Steklov Mathematical Institute of Russian Academy of Sciences, Moscow, Russia

Abstract: Unlike the Abel map of a symmetric power of a Riemann surface onto its Jacobian, the Abel–Prym map can generically not be inversed by means of conventional technique related to the Jacobi inversion problem and its main ingredient, namely Riemann's vanishing theorem. This occurs because replacing the Riemann theta function by the Prym one in this theorem gives twice as many zeros as the dimension of the Prym variety. However, if the Riemann surface has a second involution commuting with the one defining the Prym variety and satisfying a certain additional condition, an analogue of the Jacobi inversion can be defined, and expressed in terms of the Prym theta function. We formulate these conditions and refer to pairs of involutions satisfying them as pairs of the first type. We formulate necessary conditions for a pair of involutions to be a pair of the first type, and give a series of examples of curves with such pairs of involutions, which are mainly the spectral curves of Hitchin systems, and also the spectral curve of the Kovalevskaya system.
Bibliography: 14 titles.

Keywords: Abel–Prym transform, Jacobi inversion problem, Hitchin system, spectral curve.

MSC: Primary 14H40, 14H42, 14K20, 14K25; Secondary 70H06

Received: 21.05.2025 and 22.06.2025

DOI: 10.4213/sm10349


 English version:
Sbornik: Mathematics, 2025, 216:12, 1754–1772


© Steklov Math. Inst. of RAS, 2026