Julius Peter Christian Petersen (16 June 1839, Sorø, West Zealand – 5 August 1910, Copenhagen) was a Danish mathematician.
Petersen's interests in mathematics were manifold (geometry, function theory, number theory, mathematical physics, mathematical economics, cryptography and graph theory). His famous paper Die Theorie der regulären graphs was a fundamental contribution to modern graph theory as we know it today. In 1898, he presented a counterexample to Tait's claimed theorem about 1-factorability of 3-regular graphs, which is nowadays known as the "Petersen Graph".
He published a systematic treatment of geometrical constructions (with straightedge and compass) in 1880. A French translation was reprinted in 1990.
A special issue of Discrete Mathematics has been dedicated to the 150th birthday of Petersen, in which a very precise biography may be found.
- ^ Petersen, J. (1891). "Die Theorie der regulären graphs". Acta Mathematica 15 (1): 193–220. doi:10.1007/BF02392606.
- ^ Lützen, J.; Sabidussi, G. and Toft, B. (1992). "Julius Petersen 1839–1910 a biography". Discrete Mathematics 100 (1–3): 9–82. doi:10.1016/0012-365X(92)90636-T.