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arXiv · 2309.11309

Pseudo $s$-Numbers of Embeddings of Gaussian Weighted Sobolev Spaces

Van Kien Nguyen
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Abstract

In this paper, we study the approximation problem for functions in the Gaussian-weighted Sobolev space $W^α_p(\mathbb{R}^d, γ)$ of mixed smoothness $α\in \mathbb{N}$ with error measured in the Gaussian-weighted space $L_q(\mathbb{R}^d, γ)$. We obtain the exact asymptotic order of pseudo $s$-numbers for the cases $1 \leq q< p < \infty$ and $p=q=2$. Additionally, we also obtain an upper bound and a lower bound for pseudo $s$-numbers of the embedding of $W^α_2(\mathbb{R}^d, γ)$ into $L_{\infty}^{\sqrt{g}}(\mathbb{R}^d)$. Our result is an extension of that obtained in Dinh Dũng and Van Kien Nguyen (IMA Journal of Numerical Analysis, 2023) for approximation and Kolmogorov numbers.

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Van Kien Nguyen. 2023-09-28. Pseudo $s$-Numbers of Embeddings of Gaussian Weighted Sobolev Spaces. https://arxiv.org/abs/2309.11309

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