Janos Bolyai
János Bolyai (1802–1860) Hungarian mathematician (artwork made by Attila Zsigmond) Memorial plaque of János Bolyai in Olomouc, (Czech Republic). János Bolyai (Hungarian: [ˈjaː.noʃ ˈbo.jɒ.i]; 15 December 1802 – 27 January 1860) or Johann Bolyai, was a Hungarian mathematician, one of the founders of non-Euclidean geometry — a geometry that differs from Euclidean geometry in its definition of parallel lines. The discovery of a consistent alternative geometry that might correspond to the structure of the universe helped to free mathematicians to study abstract concepts irrespective of any possible connection with the physical world.