OpenAI reports cotype–cotype equivalence under approximation

For a nonzero real Banach space with the ordinary approximation property, K-convexity holds if and only if both the space and its dual have finite Rademacher cotype, with possibly different exponents.

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Understanding the problem

Read the background

For a nonzero real Banach space with the ordinary approximation property, K-convexity holds if and only if both the space and its dual have finite Rademacher cotype, with possibly different exponents.

Why it matters

If correct, resolves the cotype–cotype conjecture for the broad class of Banach spaces with the approximation property.

What counts as progress

Do finite cotype of a Banach space and its dual characterize K-convexity under approximation?

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