On the anticanonical complex

Abstract

The anticanonical complex has been introduced as a natural generalization of the toric Fano polytope and so far has been succesfully used for the study of varieties with a torus action of complexity one. In the present article we enlarge the area of application of the anticanonical complex to varieties with a torus action of higher complexity, for example, general arrangement varieties. As an application of our techniques we classify the three-dimensional canonical Fano intrinsic quadrics with automorphism group having a maximal torus of dimension one.