We study the determination of finite subsets of the integer lattice Zn, n â‰¥ 2, by X-rays. In this context, an X-ray of a set in a direction u gives the number of points in the set on each lineâ€¦ (More)

This paper studies the complexity of computing (or approximating, or bounding) the various inner and outer radii of an n-dimensional convex polytope in the space N" equipped with an gp norm or aâ€¦ (More)

This is the first part of a broaaer survey of computational convexity, an area of mathematics that has crystallized around a variety of results, problems and applications involving interactions amongâ€¦ (More)

This paper is concerned with the various inner and outer radii of a convex body C in a d-dimensional normed space. The inner j-radius rj(C) is the radius of a largest j-ball contained in C, and theâ€¦ (More)

This paper gives various (positive and negative) results on the complexity of the problem of computing and approximating mixed volumes of polytopes and more general convex bodies in arbitraryâ€¦ (More)

The paper gives strong instability results for a basic reconstruction problem of discrete tomography, an area that is particularly motivated by demands from material sciences for the reconstructionâ€¦ (More)