Janos Bolyai — Hungarian Mathematician born on December 15, 1802, died on January 27, 1860
János Bolyai 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... (wikipedia)