Abstract
In this paper we study the existence and uniqueness of solutions of the Beltrami equationf -z (z) =Μ(z)f z (z), whereΜ(z) is a measurable function defined almost everywhere in a plane domain ‡ with ‖ΜΜ∞ = 1-Here the partialsf z andf z of a complex valued functionf z exist almost everywhere. In case ‖Μ‖∞ ≤9 < 1, it is well-known that homeomorphic solutions of the Beltrami equation are quasiconformal mappings. In case ‖Μ‖∞= 1, much less is known. We give sufficient conditions onΜ(z) which imply the existence of a homeomorphic solution of the Beltrami equation, which isACL and whose partial derivativesf z andf z are locally inL q for anyq < 2. We also give uniqueness results. The conditions we consider improve already known results.
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Brakalova, M.A., Jenkins, J.A. On solutions of the Beltrami equation. J. Anal. Math. 76, 67–92 (1998). https://doi.org/10.1007/BF02786930
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DOI: https://doi.org/10.1007/BF02786930