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arXiv · 1904.00489

Discriminant and Hodge classes on the space of Hitchin's covers

Mikhail Basok
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Abstract

We continue the study of the rational Picard group of the moduli space of Hitchin's spectral covers started in P. Zograf's and D. Korotkin's work [11]. In the first part of the paper we expand the ``boundary'', ``Maxwell stratum'' and ``caustic'' divisors introduced in [11] via the set of standard generators of the rational Picard group. This generalizes the result of [11], where the expansion of the full discriminant divisor (which is a linear combination of the classes mentioned above) was obtained. In the second part of the paper we derive a formula that relates two Hodge classes in the rational Picard group of the moduli space of Hitchin's spectral covers.

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Mikhail Basok. 2019-03-31. Discriminant and Hodge classes on the space of Hitchin's covers. https://doi.org/10.1007/s11005-020-01303-y

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