Geometry of horospheres in Kobayashi hyperbolic domains

Vikramjeet Singh Chandel; Nishith Mandal

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arXiv · 2409.14114

Geometry of horospheres in Kobayashi hyperbolic domains

Vikramjeet Singh Chandel·Nishith Mandal

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Abstract

For a Kobayashi hyperbolic domain, Abate introduced the notion of small and big horospheres of a given radius at a boundary point with a pole. In this article, we investigate which domains have the property that closed big horospheres and closed small horospheres centered at a given point and of a given radius intersect the boundary only at that point? We prove that any model-Gromov-hyperbolic domain have this property. To provide examples of non-Gromov-hyperbolic domains, we show that unbounded locally model-Gromov-hyperbolic domains and bounded, Dini-smooth, locally convex domains, that are locally visible, also have this property. Finally, using the geometry of the horospheres, we present a result about the homeomorphic extension of biholomorphisms and give an application of it.

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BibTeX RIS

Vikramjeet Singh Chandel, Nishith Mandal. 2024-09-21. Geometry of horospheres in Kobayashi hyperbolic domains. https://arxiv.org/abs/2409.14114

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