Univalency of convolutions of harmonic mappings

被引:13
作者
Boyd, Z. [1 ]
Dorff, M. [1 ]
Nowak, M. [2 ]
Romney, M. [3 ]
Woloszkiewicz, M. [2 ]
机构
[1] Brigham Young Univ, Dept Math, Provo, UT 84602 USA
[2] Marie Curie Sklodowska Univ, Dept Math, PL-20031 Lublin, Poland
[3] Univ Illinois, Dept Math, Urbana, IL 61801 USA
关键词
Harmonic mappings; Convolutions; Univalence;
D O I
10.1016/j.amc.2014.01.162
中图分类号
O29 [应用数学];
学科分类号
070104 ;
摘要
We consider the convolution or Hadamard product of planar harmonic mappings that are the vertical shears of the canonical half-plane mapping phi(z)=z/(1-z)with respective dilatations -xz and -yz, where vertical bar x vertical bar = vertical bar y vertical bar = 1. We prove that any such convolution is univalent. Furthermore, in the case that x = y = -1, we show the resulting convolution is convex. (C) 2014 Elsevier Inc. All rights reserved.
引用
收藏
页码:326 / 332
页数:7
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