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On the Existence of an Element with Given Deviations from an Expanding System of Subspaces

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Abstract

We expand the class of deviation sequences for which the problem on the existence of an element of a Banach space with these deviations from a system of nested subspaces is solved positively regardless of the space and the system of subspaces. This result is used to narrow the gap between the weak asymptotics constants in S. V. Konyagin’s theorem on the existence of an element whose deviations are asymptotically close to given ones.

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References

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Acknowledgments

The author thanks P. A. Borodin for valuable remarks.

Funding

This work was financially supported by the Russian Science Foundation (project 23-71-30001, https://rscf.ru/en/project/23-71-30001/) at Lomonosov Moscow State University.

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Correspondence to Yu. A. Skvortsov.

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The author of this work declares that he has no conflicts of interest.

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Translated from Matematicheskie Zametki, 2023, Vol. 114, pp. 780–788 https://doi.org/10.4213/mzm13982.

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Skvortsov, Y.A. On the Existence of an Element with Given Deviations from an Expanding System of Subspaces. Math Notes 114, 949–956 (2023). https://doi.org/10.1134/S0001434623110299

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  • DOI: https://doi.org/10.1134/S0001434623110299

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