## Discontinuity of a degenerating escape rate

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- by Laura DeMarco and Yûsuke Okuyama PDF
- Conform. Geom. Dyn.
**22**(2018), 33-44 Request permission

## Abstract:

We look at degenerating meromorphic families of rational maps on $\mathbb {P}^1$—holomorphically parameterized by a punctured disk—and we provide examples where the bifurcation current fails to have a bounded potential in a neighborhood of the puncture. This is in contrast to the recent result of Favre-Gauthier that we always have continuity across the puncture for families of polynomials; and it provides a counterexample to a conjecture posed by Favre in 2016. We explain why our construction fails for polynomial families and for families of rational maps defined over finite extensions of the rationals $\mathbb {Q}$.## References

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## Additional Information

**Laura DeMarco**- Affiliation: Department of Mathematics, Northwestern University, 2033 Sheridan Road, Evanston, Illinois 60208
- MR Author ID: 677013
- Email: demarco@math.northwestern.edu
**Yûsuke Okuyama**- Affiliation: Division of Mathematics, Kyoto Institute of Technology, Sakyo-ku, Kyoto 606-8585, Japan
- Email: okuyama@kit.ac.jp
- Received by editor(s): October 4, 2017
- Received by editor(s) in revised form: January 31, 2018
- Published electronically: May 8, 2018
- Additional Notes: This research was partially supported by JSPS Grant-in-Aid for Scientific Research (C), 15K04924, and the National Science Foundation DMS-1600718.
- © Copyright 2018 American Mathematical Society
- Journal: Conform. Geom. Dyn.
**22**(2018), 33-44 - MSC (2010): Primary 37F45; Secondary 37P30
- DOI: https://doi.org/10.1090/ecgd/318
- MathSciNet review: 3798915