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arXiv · 1912.13236

Fractional Dehn twists and modular invariants

Xiao-Lei Liu
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Abstract

In this note, we establish a relationship between fractional Dehn twist coefficients of Riemann surface automorphisms and modular invariants of holomorphic families of algebraic curves. Specially, we give a characterization of pseudo-periodic maps with nontrivial fractional Dehn twist coefficients. We also obtain some uniform lower bounds of non-zero fractional Dehn twist coefficients.

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Xiao-Lei Liu. 2019-12-31. Fractional Dehn twists and modular invariants. https://arxiv.org/abs/1912.13236

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