On Harder-Narasimhan filtrations and their compatibility with tensor products

Christophe Cornut

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arXiv · 1703.08047

On Harder-Narasimhan filtrations and their compatibility with tensor products

Christophe Cornut

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Abstract

We attach buildings to modular lattices and use them to develop a metric approach to Harder-Narasimhan filtrations. Switching back to a categorical framework, we establish an abstract numerical criterion for the compatibility of these filtrations with tensor products. We finally verify our criterion in three cases, one of which is new.

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Christophe Cornut. 2019-11-08. On Harder-Narasimhan filtrations and their compatibility with tensor products. https://arxiv.org/abs/1703.08047

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