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arXiv · 2012.02016

Does a typical $\ell_p\,$-$\,$space contraction have a non-trivial invariant subspace?

Sophie Grivaux·Étienne Matheron·Quentin Menet
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Abstract

Given a Polish topology $\tau$ on ${{\mathcal{B}}_{1}(X)}$, the set of all contraction operators on $X=\ell_p$, $1\le p<\infty$ or $X=c_0$, we prove several results related to the following question: does a typical $T\in {{\mathcal{B}}_{1}(X)}$ in the Baire Category sense has a non-trivial invariant subspace? In other words, is there a dense $G_\delta$ set $\mathcal G\subseteq ({{\mathcal{B}}_{1}(X)},\tau)$ such that every $T\in\mathcal G$ has a non-trivial invariant subspace? We mostly focus on the Strong Operator Topology and the Strong$^*$ Operator Topology.

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Sophie Grivaux, Étienne Matheron, Quentin Menet. 2020-12-03. Does a typical $\ell_p\,$-$\,$space contraction have a non-trivial invariant subspace?. https://arxiv.org/abs/2012.02016

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