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arXiv · 1907.00834

The CR Ahlfors derivative and a new invariant for spherically equivalent CR maps

Bernhard Lamel·Duong Ngoc Son
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Abstract

We study a CR analogue of the Ahlfors derivative for conformal immersions of Stowe [23] that generalizes the CR Schwarzian derivative studied earlier by the second-named author [21]. This notion possesses several important properties similar to those of the conformal counterpart and provides a new invariant for spherically equivalent CR maps from strictly pseudoconvex CR manifolds into a sphere. The invariant is computable and distinguishes many well-known sphere maps. In particular, it vanishes precisely when the map is spherically equivalent to the linear embedding of spheres.

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Bernhard Lamel, Duong Ngoc Son. 2020-10-30. The CR Ahlfors derivative and a new invariant for spherically equivalent CR maps. https://doi.org/10.5802/aif.3438

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