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تسجيل مستخدم جديدGelfand numbers of embeddings of Schatten classes
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Let $0<p,qleq infty$ and denote by $mathcal{S}_p^N$ and $mathcal{S}_q^N$ the corresponding Schatten classes of real $Ntimes N$ matrices. We study the Gelfand numbers of natural identities $mathcal{S}_p^Nhookrightarrow mathcal{S}_q^N$ between Schatten classes and prove asymptotically sharp bounds up to constants only depending on $p$ and $q$. This extends classical results for finite-dimensional $ell_p$ sequence spaces by E. Gluskin to the non-commutative setting and complements bounds previously obtained by B. Carl and A. Defant, A. Hinrichs and C. Michels, and J. Chavez-Dominguez and D. Kutzarova.
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Let $0<p,qleq infty$ and denote by $mathcal S_p^N$ and $mathcal S_q^N$ the corresponding Schatten classes of real $Ntimes N$ matrices. We study approximation quantities of natural identities $mathcal S_p^Nhookrightarrow mathcal S_q^N$ between Schatte
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