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Imre Bárány

Publications and source records attributed to Imre Bárány.

39 records · Page 3Linked to original sources

Random points, convex bodies, lattices

Assume $K$ is a convex body in $R^d$, and $X$ is a (large) finite subset of $K$. How many convex polytopes are there whose vertices come from $X$? What is the typical shape of such a polytope? How well the largest such polytope (which is actually $\conv X$) approximates $K$? We are interested in these questions mainly in two cases. The first is when $X$ is a random sample of $n$ uniform, independent points from $K$ and is motivated by Sylvester's four-point problem, and by the theory of random polytopes. The second case is when $X=K \cap Z^d$ where $Z^d$ is the lattice of integer points in $R^d$. Motivation comes from integer programming and geometry of numbers. The two cases behave quite similarly.

math.CO↗

Covering lattice points by subspaces

We find tight estimates for the minimum number of proper subspaces needed to cover all lattice points in an n-dimensional convex body symmetric about the origin. We also find the order of magnitude of the number of (n-1)-dimensional subspaces induced by the lattice points in a large n-dimensional ball centered at the origin.

math.NT↗

Universal Counting of Lattice Points in Polytopes

Given a lattice polytope $P$ (with underlying lattice $\lo$), the universal counting function $\uu_P(\lo')=|P\cap \lo'|$ is defined on all lattices $\lo'$ containing $\lo$. Motivated by questions concerning lattice polytopes and the Ehrhart polynomial, we study the equation $\uu_P=\uu_Q$.

math.CO↗