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arXiv · 2109.15001

Attaining strong diameter two property for infinite cardinals

Stefano Ciaci·Johann Langemets·Aleksei Lissitsin
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Abstract

We extend the (attaining of) strong diameter two property to infinite cardinals. In particular, a Banach space has the 1-norming attaining strong diameter two property with respect to $\omega$ (1-ASD2P$_\omega$ for short) if every convex series of slices of the unit ball intersects the unit sphere. We characterize $C(K)$ spaces and $L_1(\mu)$ spaces having the 1-ASD2P$_\omega$. We establish dual implications between the 1-ASD2P$_\omega$, $\omega$-octahedral norms and Banach spaces failing the $(-1)$-ball-covering property. The stability of these new properties under direct sums and tensor products is also investigated.

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Stefano Ciaci, Johann Langemets, Aleksei Lissitsin. 2021-09-30. Attaining strong diameter two property for infinite cardinals. https://arxiv.org/abs/2109.15001

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