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arXiv · 1912.13312

A note on universal operators between separable Banach spaces

Joanna Garbulińska-Wegrzyn·Wieslaw Kubiś
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Abstract

We compare two types of universal operators constructed relatively recently by Cabello S\'anchez, and the authors. The first operator $\Omega$ acts on the Gurarii space, while the second one $P_S$ has values in a fixed separable Banach space $S$. We show that if $S$ is the Gurarii space, then both operators are isometric. We also prove that, for a fixed space $S$, the operator $P_S$ is isometrically unique. Finally, we show that $\Omega$ is generic in the sense of a natural infinite game.

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Joanna Garbulińska-Wegrzyn, Wieslaw Kubiś. 2019-12-31. A note on universal operators between separable Banach spaces. https://doi.org/10.1007/s13398-020-00878-4

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