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arXiv · 1506.09066

Rotation number and lifts of a Fuchsian action of the modular group on the circle

Yoshifumi Matsuda
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Abstract

We characterize the semi-conjugacy class of a Fuchsian action of the modular group on the circle in terms of rotation numbers of two standard generators and that of their product. We also show that among lifts of a Fuchsian action of the modular group, only 5-fold lift admits a similar characterization. These results indicate similarity and difference between rotation number and linear character.

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Yoshifumi Matsuda. 2015-06-30. Rotation number and lifts of a Fuchsian action of the modular group on the circle. https://arxiv.org/abs/1506.09066

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