Distance Ratio Metric

  • Vesna Todorčević


The basic distortion results about quasiconformal mappings such as the Schwarz lemma and the Gehring–Osgood theorem say that these mappings are Hölder continuous with respect to the hyperbolic and the quasihyperbolic metric respectively. In this chapter we analyze the modulus of continuity in the case of the distance ratio metric. The natural question is to find Lipschitz constants for this metric under Möbius transformations or arbitrary holomorphic mappings. The domains we work with here are the unit ball, the punctured ball, and the upper half space.


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Authors and Affiliations

  • Vesna Todorčević
    • 1
    • 2
  1. 1.Faculty of Organizational SciencesUniversity of BelgradeBelgradeSerbia
  2. 2.Mathematical InstituteSerbian Academy of Sciences and ArtsBelgradeSerbia

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