Extended Set Difference : Inverse Operation of Minkowski Summation
Arie Beresteanu, Behrooz Moosavi Ramezanzadeh
TL;DR
The paper addresses the lack of a genuine inverse for Minkowski summation by introducing the extended set difference $A \ominus_e B$, defined as the collection of minimizers of the Hausdorff distance $d_H(A, B \oplus X)$ over $X \in \mathcal{K}^d_{kc}$. Existence of minimizers is established, and the authors analyze properties, symmetry, convergence, and bounds, while presenting a unique solution strategy via strictly convex perturbations. A practical, LP-based computation framework in the space of support functions is developed, enabling efficient approximation of $A \ominus_e B$ by convex polygons and successful application to multiple geometric configurations. The approach provides a robust, constructive tool for set-valued arithmetic in higher dimensions with potential applications in optimization, computer vision, and geometric analysis.
Abstract
This paper introduces the extended set difference, a generalization of the Hukuhara and generalized Hukuhara differences, defined for compact convex sets in $\mathbb{R}^d$. The proposed difference guarantees existence for any pair of such sets, offering a broader framework for set arithmetic. The difference may not be necessarily unique, but we offer a bound on the variety of solutions. The definition of the extended set difference is formulated through an optimization problem, which provides a constructive approach to its computation. The paper explores the properties of this new difference, including its stability under orthogonal transformations and its robustness to perturbations of the input sets. We propose a method to compute this difference through a formulated linear optimization problem.
