On extreme contractions between real Banach spaces
نویسندگان
چکیده
We completely characterize extreme contractions between two-dimensional strictly convex and smooth real Banach spaces, perhaps for the very first time. In order to obtain desired characterization, we introduce notions of (weakly) compatible point pair (CPP) μ-compatible (μ-CPP) in geometry spaces. As a concrete application our abstract results, describe all rank one L(ℓ42,ℓ42) L(ℓ42,H), where H is any Hilbert space. also prove that there does not exist L(H,ℓp2), whenever p even Finally, spaces among terms CPP, substantiates motivation behind introducing these new geometric notions.
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ژورنال
عنوان ژورنال: Expositiones Mathematicae
سال: 2021
ISSN: ['1878-0792', '0723-0869']
DOI: https://doi.org/10.1016/j.exmath.2019.09.004