Teichmüller's problem in space

: Klen R, Todorcevic V, Vuorinen M

Publisher: ACADEMIC PRESS INC ELSEVIER SCIENCE

: 2017

: Journal of Mathematical Analysis and Applications

: JOURNAL OF MATHEMATICAL ANALYSIS AND APPLICATIONS

: J MATH ANAL APPL

: 455

: 1-2

: 1297

: 1316

: 20

: 0022-247X

DOI: https://doi.org/10.1016/j.jmaa.2017.06.026

Quasiconformal homeomorphisms of the whole space, onto itself normalized at one or two points are studied. In particular, the stability theory, the case when the maximal dilatation tends to 1, is in the focus. Our main result provides a spatial analogue of a classical result due to Teichmuller. Unlike Teichmuller's result, our bounds are explicit. Explicit bounds are based on two sharp well-known distortion results: the quasiconformal Schwarz lemma and the bound for linear dilatation. Moreover, Bernoulli type inequalities and asymptotically sharp bounds for special functions involving complete elliptic integrals are applied to simplify the computations. Finally, we discuss the behavior of the quasihyperbolic metric under quasiconformal maps and prove a sharp result for quasiconformal maps of R-n {0} onto itself. (C) 2017 Elsevier Inc. All rights reserved.