Further inequalities for the (generalized) Wills functional

Abstract

The Wills functional $\mathcal{W}(K)$ of a convex body $K$, defined as the sum of its intrinsic volumes $\mathrm{V}_i(K)$, turns out to have many interesting applications and properties. In this paper we make profit of the fact that it can be represented as the integral of a log-concave function, which, furthermore, is the Asplund product of other two log-concave functions, and obtain new properties of the Wills functional (indeed, we will work in a more general setting). Among others, we get upper bounds for $\mathcal{W}(K)$ in terms of the volume of $K$, as well as Brunn-Minkowski and Rogers-Shephard type inequalities for this functional. We also show that the cube of edge-length 2 maximizes $\mathcal{W}(K)$ among all $0$-symmetric convex bodies in John position, and we reprove the well-known McMullen inequality $\mathcal{W}(K)\leq e^{\mathrm{V}_1(K)}$ using a different approach.