Journals / Turkish Journal of Mathematics / 2019 / Cilt: 43 - Sayı: 5

A remark on a paper of P. B. Djakov and M. S. Ramanujan

Pages
2494–2498
Publication Date
2022-11-04
DOI
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AI Summary & Key Takeaways

AI Insight
⚡ TL;DR(Too Long; Didn't Read)

As an application, we observethat the existence of an unbounded operator between ℓ -Köthe spaces, under a splitting condition, causes the existenceof a common basic subspace.

📌 3 Key Takeaways

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Objective & Hypothesis:Let ℓ be a Banach sequence space with a monotone norm in which the canonical system $(e_n)$ is anunconditional basis.
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Key Findings & Data:We show that if there exists a continuous linear unbounded operator between ℓ -Köthe spaces, thenthere exists a continuous unbounded quasidiagonal operator between them.
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Conclusion & Impact:As an application, we observethat the existence of an unbounded operator between ℓ -Köthe spaces, under a splitting condition, causes the existenceof a common basic subspace.
🔬Design:Research Article
📍Scope:Comprehensive Sample
⚙️Variables:Domain Parameters

Abstract

Let ℓ be a Banach sequence space with a monotone norm in which the canonical system $(e_n)$ is anunconditional basis. We show that if there exists a continuous linear unbounded operator between ℓ -Köthe spaces, thenthere exists a continuous unbounded quasidiagonal operator between them. Using this result, we study the correspondingKöthe matrices when every continuous linear operator between ℓ -Köthe spaces is bounded. As an application, we observethat the existence of an unbounded operator between ℓ -Köthe spaces, under a splitting condition, causes the existenceof a common basic subspace.

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Cite This Article

YURDAKUL, M. H., UYANIK, E. (2022). A remark on a paper of P. B. Djakov and M. S. Ramanujan. Turkish Journal of Mathematics, Cilt: 43 - Sayı: 5, 2494–2498. https://ajindex.com/articles/607666

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References (8)

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