English

Entropy numbers of diagonal operators on Orlicz sequence spaces

Functional Analysis 2021-07-01 v1

Abstract

Let M1M_1 and M2M_2 be functions on [0,1][0,1] such that M1(t1/p)M_1(t^{1/p}) and M2(t1/p)M_2(t^{1/p}) are Orlicz functions for some p(0,1].p \in (0,1]. Assume that M21(1/t)/M11(1/t)M_2^{-1} (1/t)/M_1^{-1} (1/t) is non-decreasing for t1.t \geq 1. Let (αi)i=1(\alpha_i)_{i=1}^\infty be a non-increasing sequence of non-negative real numbers. Under some conditions on (αi)i=1,(\alpha_i)_{i=1}^\infty, sharp two-sided estimates for entropy numbers of diagonal operators Tα:M1M2T_\alpha :\ell_{M_1} \rightarrow \ell_{M_2} generated by (αi)i=1,(\alpha_i)_{i=1}^\infty, where M1\ell_{M_1} and M2\ell_{M_2} are Orlicz sequence spaces, are proved. The results generalise some works of Edmunds and Netrusov and hence a result of Cobos, K\"{u}hn and Schonbek.

Keywords

Cite

@article{arxiv.2106.15660,
  title  = {Entropy numbers of diagonal operators on Orlicz sequence spaces},
  author = {Thanatkrit Kaewtem and Yuri Netrusov},
  journal= {arXiv preprint arXiv:2106.15660},
  year   = {2021}
}