Abstract
We study the weak convergence of a greedy algorithm of approximation by a given set in a Banach space. It is proved that the greedy algorithm of approximation by a strongly norm-reducing set in a uniformly smooth Banach space with the WN-property weakly converges. In an arbitrary separable Banach space without the WN-property, we construct an example of a strongly norm-reducing set such that the greedy algorithm of approximation by this set does not weakly converge for some initial element.
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References
S. J. Dilworth, D. Kutzarova, K. L. Shuman, V. N. Temlyakov, and P. Wojtaszczyk, “Weak convergence of greedy algorithms in Banach spaces,” J. Fourier Anal. Appl. 14 (5–6), 609–628 (2008).
V. Temlyakov, Greedy Approximation (Cambridge Univ. Press, Cambridge, 2011).
V. N. Temlyakov, “Nonlinear methods of approximation,” Found. Comput. Math. 3 (1), 33–107 (2003).
V. N. Temlyakov, “Greedy approximation in Banach spaces,” in Banach Spaces and Their Applications in Analysis (de Gruyter, Berlin, 2007), pp. 193–208.
E. D. Livshits, “Convergence of greedy algorithms in Banach spaces,” Math. Notes 73 (3), 342–358 (2003).
P. A. Borodin, “Greedy approximation by arbitrary sets,” Izv. Math. 84 (2), 246–261 (2020).
J. Diestel, Geometry of Banach Spaces (Springer, Berlin–New York, 1975).
V. I. Bogachev and O. G. Smolyanov, Real and Functional Analysis (Regular and Chaotic Dynamics, Moscow–Izhevsk, 2020) [in Russian].
Funding
This work was supported by the Russian Science Foundation under grant no. 22-21-00415.
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Translated from Matematicheskie Zametki, 2023, Vol. 113, pp. 483–488 https://doi.org/10.4213/mzm13667.
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Borodin, P.A. Weak Convergence of a Greedy Algorithm and the WN-Property. Math Notes 113, 475–479 (2023). https://doi.org/10.1134/S0001434623030197
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DOI: https://doi.org/10.1134/S0001434623030197