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arXiv · 1405.4499

Ordinal indices for complemented subspaces of l_p

S. Dutta·D. Khurana
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Abstract

We provide complete isomorphic invariance of a class of translation invariant complemented subspaces of L_p constructed by Bourgain, Rosenthal and Schechtman. We compute ordinal L_p-indices for this class. We further show that the isometric index of a tree subspace over a well founded tree is an invariance for the order of the tree. Finally we provide a dichotomy for the subspaces of L_p with small ordinal indices.

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S. Dutta, D. Khurana. 2014-05-18. Ordinal indices for complemented subspaces of l_p. https://arxiv.org/abs/1405.4499

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