Locally finite root systems

We develop the basic theory of root systems R in a real vector space X which are defined in analogy to the usual finite root systems, except that finiteness is replaced by local finiteness: The intersection of R with every finite-dimensional subspace of X is finite. The main topics are Weyl groups, parabolic subsets and positive systems, weights, and gradings.

AMS subject classification: 17B10, 17B20, 20F55

(This paper has appeared in Memoirs Amer. Math. Soc. 171 (2004), no. 811)


O. Loos < ottmar.loos@uibk.ac.at >

E. Neher < neher@uottawa.ca >