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arXiv · 1102.0681

Widths of embeddings in weighted function spaces

Shun Zhang·Gensun Fang
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Abstract

We study the asymptotic behaviour of the approximation, Gelfand and Kolmogorov numbers of the compact embeddings of weighted function spaces of Besov and Triebel-Lizorkin type in the case where the weights belong to a large class. We obtain the exact estimates in almost all nonlimiting situations where the quasi-Banach setting is included. At the end we present complete results on related widths for polynomial weights with small perturbations, in particular the sharp estimates in the case $\alpha=d(\frac 1{p_2}-\frac 1{p_1})>0$ therein.

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Shun Zhang, Gensun Fang. 2011-02-03. Widths of embeddings in weighted function spaces. https://doi.org/10.1016/j.jat.2012.11.011

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