A new short proof of the following assertion is presented. Given an integer k and a sequence of closed linear subspaces of a Banach space, assume that the codimension of each subspace does not exceed k. Then the upper topological limit of this sequence contains a closed linear subspace with codimension not exceeding k.

Contact details are reproduced from the original publication and may be historical.

Aram V. Arutyunov

V. A. Trapeznikov Institute of Control Sciences, Russian Academy of Sciences, Moscow, Russia

arutyunov@cs.msu.ru
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A. V. Arutyunov. “Lower Bound of the Upper Topological Limit of a Sequence of Subspaces.” Journal of Convex Analysis 27 (2020), No. 1, 49–51. https://doi.org/10.68381/jca27004