Presentation and uniqueness of Kac-Moody groups over local rings

Timothée Marquis, Bernhard Mühlherr

To any generalised Cartan matrix (GCM) $A$ and any ring $R$, Tits associated a Kac-Moody group ${\mathfrak{G}}_A(R)$ defined by a presentation à la Steinberg. For a domain $R$ with f…