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arXiv · 1212.4646

Strong Banach property (T), after Vincent Lafforgue

Benben Liao
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Abstract

This text takes, with more details and simplifying a proof in section 3, the parts of [Laf08] and [Laf09] treating p-adic groups. We prove that $SL_{3}$ over a non archimedian local field $F$ has strong Banach property (T). The applications are as follows: any connected almost $F$-simple algebraic group $G$ over $F$ whose Lie algebra contains $sl_3(F)$ has strong Banach property (T), the family of expanders constructed from a lattice of $G(F)$ do not embed uniformly in any Banach space of type $>1,$ and any isometric affine action of $G(F)$ on a Banach space of type $>1$ admits a fix point.

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Benben Liao. 2012-12-19. Strong Banach property (T), after Vincent Lafforgue. https://arxiv.org/abs/1212.4646

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