## Shears for quasisymmetric maps

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**149**(2021), 2487-2499 Request permission

## Abstract:

We give an elementary proof of a theorem that characterizes quasisymmetric maps of the unit circle in terms of shear coordinates on the Farey tesselation. The proof only uses the normal family argument for quasisymmetric maps and some elementary hyperbolic geometry.## References

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## Additional Information

**Dragomir Šarić**- Affiliation: Department of Mathematics, CUNY Graduate Center, 365 Fifth Avenue, Room 4208, New York, New York 10016-4309; and Department of Mathematics, Queens College, The City University of New York, 237 Kiely Hall, 65-30 Kissena Blvd., Flushing, New York 11367
- Email: Dragomir.Saric@qc.cuny.edu
- Received by editor(s): April 6, 2020
- Received by editor(s) in revised form: August 22, 2020
- Published electronically: March 29, 2021
- Communicated by: David Futer
- © Copyright 2021 American Mathematical Society
- Journal: Proc. Amer. Math. Soc.
**149**(2021), 2487-2499 - MSC (2020): Primary 30F45, 30F60
- DOI: https://doi.org/10.1090/proc/15437
- MathSciNet review: 4246800