Eugenio Beltrami
Eugenio Beltrami (16 November 1835 – 18 February 1900) was an Italian mathematician notable for his work on non-Euclidean geometry, electricity, and magnetism.
He was born in Cremona in Lombardy, then a part of the Austrian Empire, and now part of Italy. Beltrami first began studying mathematics at the University of Pavia in 1853, but was forced to discontinue his studies in 1856 because of financial hardship. He was appointed to the University of Bologna as a professor in 1862, the year he published his first paper. Beltrami later taught at universities in Pisa, Rome and Pavia. He died in Rome in 1900.
In 1868, (in Essay on an interpretation of non-Euclidean geometry) Beltrami gave the first model of hyperbolic geometry. In Beltrami's model, lines of hyperbolic geometry are represented by geodesics on the pseudosphere. Beltrami provided the first proof that Euclid's parallel postulate could not be derived from the other axioms of Euclidean geometry.