LATTICES OF MINIMUM COVOLUME IN CHEVALLEY GROUPS OVER LOCAL FIELDS OF POSITIVE CHARACTERISTIC

摘要

In. this article, we show that if G is a simply connected Chevalley group of either classical type of rank bigger than 1 or type E-6 and if q > 9 is a power of a prime number p > 5, then G = G(F-q((t(-1)))), up to an automorphism, has a unique lattice of minimum covolume, which is G(Fq[t]).