Maximum-rank root subsystems of hyperbolic root systems
Maximum-rank root subsystems of hyperbolic root systems
A Kac-Moody algebra is called hyperbolic if it corresponds to a generalized Cartan matrix of hyperbolic type.We study root subsystems of root systems of hyperbolic algebras.In this paper, we classify maximal rank regular hyperbolic subalgebras of hyperbolic Kac-Moody algebras.