Imre Z. Ruzsa

Imre Z. Ruzsa ( born July 23, 1953 in Budapest) is a Hungarian mathematician who deals with combinatorics, number theory and probability theory.

Ruzsa won a silver medal in 1969 and 1970 and 1971 gold medals ( with best scores ) at the International Mathematical Olympiad. He studied at the Lorand Eötvös University in Budapest with the conclusion of 1976. Afterwards he was at the Alfred Renyi Institute of the Hungarian Academy of Sciences.

In 1987 he proved a theorem on the minimum number of elements in the essential components, a concept of additive number theory derived from Alexander Khinchin and sets of natural numbers called, which adds to quantities with Schnirelmann densities (after Lew Genrichowitsch Schnirelman ) between 0 and 1, these densities increase. Essential components have by the theorem of Ruzsa least elements less than or equal to x ( also he proved that there is an essential component for each of these properties).

In 1994, he gave a new proof of the theorem of Gregory Freiman in the additive number theory.

In 1988 he was awarded the Rollo Davidson Prize. He was invited speaker at the International Congress of Mathematicians in Madrid 2006 ( Additive Combinatorics and Geometry of Numbers ) and at the European Congress of Mathematicians in Stockholm in 2004. He is a Fellow of the American Mathematical Society.

Writings

• With Endre Szemerédi 'Triple systems with no six points carrying three triangles, Colloq. Math Soc. János Bolyai, Vol 18, North -Holland, Amsterdam - New York, 1978, pp. 939-945.
• Essential components, Proceedings of the London Mathematical Society, Volume 54, 1987, p.38 - 56th
• Generalized arithmetical progressions and sumsets, Acta Mathematica Hungarica, Volume 65 1994, pp. 379-388 ( set of Freiman )
• The Brunn - Minkowski inequality and nonconvex sets, Geometriae Dedicata, Vol.67, 1997, pp. 337-348
• Gábor Székely with J. Algebraic Probability Theory, Wiley 1988