Symmetry (Aug 2023)

On Ulam Stability with Respect to 2-Norm

  • Janusz Brzdęk

DOI
https://doi.org/10.3390/sym15091664
Journal volume & issue
Vol. 15, no. 9
p. 1664

Abstract

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The Ulam stability of various equations (e.g., differential, difference, integral, and functional) concerns the following issue: how much does an approximate solution of an equation differ from its exact solutions? This paper presents methods that allow to easily obtain numerous general Ulam stability results with respect to the 2-norms. In four examples, we show how to deduce them from the already known outcomes obtained for classical normed spaces. We also provide some simple consequences of our results. Thus, we demonstrate that there is a significant symmetry between such results in classical normed spaces and in 2-normed spaces.

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