On discrete subgroups of Euclidean spaces (Lenny Fukshansky, CMC)
Roberts North 105, CMC 320 E. 9th St., Claremont, CA, United StatesLet x_1,...,x_n be an overdetermined spanning set for the Euclidean space R^k, where n > k. Let L be the integer span of these vectors. Then L is an additive subgroup of R^n. When is it discrete in R^n? Naturally, this depends on the choice of the spanning set, but in which way? We will […]