A1 Refereed original research article in a scientific journal

On quasi-inversions




AuthorsKalaj D, Vuorinen M, Wang GD

PublisherSPRINGER WIEN

Publication year2016

Journal:Monatshefte für Mathematik

Journal name in sourceMONATSHEFTE FUR MATHEMATIK

Journal acronymMONATSH MATH

Volume180

Issue4

First page 785

Last page813

Number of pages29

ISSN0026-9255

DOIhttps://doi.org/10.1007/s00605-016-0919-8


Abstract
Given a bounded domain strictly starlike with respect to we define a quasi-inversion w.r.t. the boundary We show that the quasi-inversion is bi-Lipschitz w.r.t. the chordal metric if and only if every "tangent line" of is far away from the origin. Moreover, the bi-Lipschitz constant tends to 1, when approaches the unit sphere in a suitable way. For the formulation of our results we use the concept of the -tangent condition due to Gehring and Vaisala (Acta Math 114:1-70,1965). This condition is shown to be equivalent to the bi-Lipschitz and quasiconformal extension property of what we call the polar parametrization of . In addition, we show that the polar parametrization, which is a mapping of the unit sphere onto , is bi-Lipschitz if and only if D satisfies the -tangent condition.



Last updated on 2024-26-11 at 23:22