Smooth separated Deligne–Mumford stack of finite type over Spec ℤ, describing elliptic curves of a specified genus g with a specified number n of marked points, which fails to be a scheme due to nontrivial automorphisms of elliptic curves
smooth separated Deligne–Mumford stack of finite type over Spec ℤ, describing elliptic curves of a specified genus g with a specified number n of marked points, which fails to be a scheme due to nontrivial automorphisms of elliptic curves (en)