Operators Reversing Orthogonality and Characterization of Inner Product Spaces
نویسنده
چکیده
In this short paper we answer a question posed by Chmieliński in [Adv. Oper. Theory 1 (2016), no. 1, 8–14]. Namely, we prove that among normed spaces of dimension greater than two, only inner product spaces admit nonzero linear operators which reverse the Birkhoff orthogonality.
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