Posts by Eduard Grigoriciuc

Abstract

In this paper, our interest is devoted to study the convex combinations of the form \((1-\lambda)f+\lambda g\) where \(\lambda \in(0,1)\) of biholomorphic mappings on the Euclidean unit ball \({\mathbb B}^n\) the case of several complex variables. Starting from a result proved by S. Trimble [26] and then extended by P.N. Chichra and R. Singh [3, Th. 2] which says that if f is starlike such that \(Re[f'(z)]>0\) then \((1-\lambda)z+\lambda f(z)\) is also starlike, we are interested to extend this result to higher dimensions.

In the first part of the paper, we construct starlike convex combinations using the identity mapping on \({\mathbb B}^n\) and some particular starlike mappings on \({\mathbb B}^n\).

In the second part of the paper, we define the class \(L_{\lambda}^∗B^n\) and prove results involving convex combinations of normalized locally biholomorphic mappings and Loewner chains. Finally, we propose a conjecture that generalize the result proved by Chichra and Singh.

Authors

Eduard Stefan Grigoriciuc
Babes-Bolyai” University, Faculty of Mathematics and Computer Science, Cluj-Napoca, Romania
”Tiberiu Popoviciu” Institute of Numerical Analysis, Romanian Academy, Cluj-Napoca, Romania

Keywords

Biholomorphic mappings; Convex sums; Starlike mappings; Herglotz vector field; Loewner chains

Paper coordinates

E.S. Grigoriciuc, On some convex combinations of biholomorphic mappings in several complex variables, Filomat 36 (16) (2022), 5503-5519;
https://doi.org/10.2298/FIL226503G

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About this paper

Journal

Filomat

Publisher Name

Faculty of Sciences and Mathematics, University of Nis, Serbia

Print ISSN

2406-0933

Online ISSN

google scholar link

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