Abstract
On every subspace of l ∞(ℕ) which contains an uncountable ω-independent set, we construct equivalent norms whose Banach-Mazur distance is as large as required. Under Martin’s Maximum Axiom (MM), it follows that the Banach-Mazur diameter of the set of equivalent norms on every infinite-dimensional subspace of l ∞(ℕ) is infinite. This provides a partial answer to a question asked by Johnson and Odell.
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Godefroy, G. On the diameter of the Banach-Mazur set. Czech Math J 60, 95–100 (2010). https://doi.org/10.1007/s10587-010-0021-7
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DOI: https://doi.org/10.1007/s10587-010-0021-7