On Vorontsov's theorem on K3 surfaces

K. Oguiso; D. -Q. Zhang

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On Vorontsov's theorem on K3 surfaces

K. Oguiso·D. -Q. Zhang

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Abstract

Let X be a K3 surface with the Neron-Severi lattice S_X and transcendental lattice T_X. Nukulin considered the kernel H_X of the natural representation Aut(X) ---> O(S_X) and proved that H_{X} is a finite cyclic group with phi(h(X))) | t(X) and acts faithfully on the space H^{2,0}(X) = C omega_{X}, where h(X) = ord(H_X), t(X) = rank T_X and phi(.) is the Euler function. Consider the extremal case where phi(h(X)) = t(X). In the situation where T_{X} is unimodular, Kondo has determined the list of t(X), as well as the actual realizations, and showed that t(X) alone uniquely determines the isomorphism class of X (with phi(h(X)) = t(X)). We settle the remaining situation where T_X is not unimodular. Together, we provide the proof for the theorem announced by Vorontsov.

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BibTeX RIS

K. Oguiso, D. -Q. Zhang. 1999-06-01. On Vorontsov's theorem on K3 surfaces. https://arxiv.org/abs/math/9906006

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