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arXiv · 1308.3952

Automorphisms of surfaces of general type with q=1 acting trivially in cohomology

Jin-Xing Cai·Wenfei Liu
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Abstract

Let S be a complex minimal surface of general type with irregularity q(S)=1 and Aut_0(S) the subgroup of automorphisms acting trivially on the cohomology ring with rational coefficients. In this paper we show that |Aut_0(S)|<=4, and if the equality holds then $S$ is a surface isogenous to a product of unmixed type. Moreover, examples of surfaces with |Aut_0(S)|=4 and all possible values of the geometric genus are provided.

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Jin-Xing Cai, Wenfei Liu. 2013-08-19. Automorphisms of surfaces of general type with q=1 acting trivially in cohomology. https://doi.org/10.2422/2036-2145.201604_012

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