Publication at Faculty of Mathematics and Physics |
2007
Abstract
(This paper is an extended abstract.) We say that two point sets A,B have identical X-rays in direction u if every line parallel to u contains the same number of points of A as points of B. We define F(k) as the maximum n such that there exist k directions for which no two n-point sets have the same X-rays in all of these k directions.
We give almost matching upper and lower bounds on F(k) by a combination of linear-algebraic, combinatorial, and probabilistic methods.