Best constants for Lipschitz embeddings of metric spaces into c
نویسندگان
چکیده
We answer a question of Aharoni by showing that every separable metric space can be Lipschitz 2-embedded into c0 and this result is sharp; this improves earlier estimates of Aharoni, Assouad and Pelant. We use our methods to examine the best constant for Lipschitz embeddings of the classical `p-spaces into c0 and give other applications. We prove that if a Banach space embeds almost isometrically into c0, then it embeds linearly almost isometrically into c0. We also study Lipschitz embeddings into c + 0 .
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