Positive cones of dual cycle classes

Abstract

We study generalizations for higher codimension cycles of several well-known definitions of the nef cone of divisors on a projective variety. These generalizations fix some of the pathologies exhibited by the classical nef cone of higher codimension classes. As an application, we recover the expected properties of the pseudoeffective cones ${\overline{Eff}}_k(X)$ for all k.

25 pages, v2: minor changes