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A New Axiomatics for Masures

Published online by Cambridge University Press:  29 January 2019

Auguste Hébert*
Affiliation:
Université de Lyon, UJM-Saint-Etienne CNRS, UMR CNRS 5208, F-42023, Saint-Etienne, France Email: [email protected]

Abstract

Masures are generalizations of Bruhat–Tits buildings. They were introduced by Gaussent and Rousseau to study Kac–Moody groups over ultrametric fields that generalize reductive groups. Rousseau gave an axiomatic definition of these spaces. We propose an equivalent axiomatic definition, which is shorter, more practical, and closer to the axiom of Bruhat–Tits buildings. Our main tool to prove the equivalence of the axioms is the study of the convexity properties in masures.

Type
Article
Copyright
© Canadian Mathematical Society 2019

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Footnotes

The author was partially supported by ANR grant ANR-15-CE40-0012.

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