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arXiv · 2610.18041

Completely symmetric subspaces of noncommutative $L_p$-spaces

Jinghao Huang
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Abstract

Let $2<p<\infty$. We prove that every infinite-dimensional closed subspace $F$ of a noncommutative $L_p$-space contains a subspace completely isomorphic to $\ell_p$, $C_p$, $R_p$, or $C_p\cap R_p$ and completely complemented in $F$. This answers the question of Junge and Xu on the existence of completely symmetric basic sequences.

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Jinghao Huang. 2026-10-13. Completely symmetric subspaces of noncommutative $L_p$-spaces. https://arxiv.org/abs/2610.18041

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