
Linear Combinations of Composition Operators on Weighted Dirichlet Spaces 
Time:20151127 
CHEN Peng School of Mathematics and Statistic, Wuhan University, Wuhan 430072, Hubei, China 
Abstract:In this paper, linear combinations of composition operators acting on weighted Dirichlet spaces are studied. By using the first derivative of the kernel function, we obtain a lower estimate for the essential norms of these operators acting on the Dirichlet space D and S2 . For general weighted Dirichlet space, by using complex interpolation methods, we characterize the compactness of these operators induced by linear fractional selfmaps of the disk. 
Key words:linear combinations of composition operator; compact operator; weighted Dirichlet spaces; complex interpolation 
CLC number:O 177.92 

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