Julius Petersen (nonfiction)

Julius Peter Christian Petersen.

Julius Peter Christian Petersen (16 June 1839, Sorø, West Zealand – 5 August 1910, Copenhagen) was a Danish mathematician. His contributions to the field of mathematics led to the birth of graph theory.

Petersen's interests in mathematics were manifold, including: geometry, complex analysis, 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".

In cryptography and mathematical economics he made contributions which today are seen as pioneering.

He published a systematic treatment of geometrical constructions (with straightedge and compass) in 1880.

Petersen, as he claimed, had a very independent way of thinking. In order to preserve this independence he made a habit to read as little as possible of other people’s mathematics, pushing it to extremes. The consequences for his lack of knowledge of the literature of the time were severe. He spent a significant part of his time rediscovering already known results, in other cases already existing results had to be removed from a submitted paper and in other more serious cases a paper did not get published at all.

He started from very modest beginnings, and by hard work, some luck and some good connections, moved steadily upward to a station of considerable importance. In 1891 his work received royal recognition through the award of the Order of the Dannebrog. Among mathematicians he enjoyed an international reputation. At his death –which was front page news in Copenhagen– the socialist newspaper Social-Demokraten correctly sensed the popular appeal of his story: here was a kind of Hans Christian Andersen of science, a child of the people who had made good in the intellectual world.

Nonfiction cross-reference

• Mathematician (nonfiction)
• Petersen family (nonfiction)

External links:

• Julius Petersen @ Wikipedia