Karel Petr (; 14 June 1868, Zbyslav,

Austria-Hungary Austria-Hungary, also referred to as the Austro-Hungarian Empire, the Dual Monarchy or the Habsburg Monarchy, was a multi-national constitutional monarchy in Central Europe#Before World War I, Central Europe between 1867 and 1918. A military ...

– 14 February 1950,

Prague Prague ( ; ) is the capital and List of cities and towns in the Czech Republic, largest city of the Czech Republic and the historical capital of Bohemia. Prague, located on the Vltava River, has a population of about 1.4 million, while its P ...

Czechoslovakia Czechoslovakia ( ; Czech language, Czech and , ''Česko-Slovensko'') was a landlocked country in Central Europe, created in 1918, when it declared its independence from Austria-Hungary. In 1938, after the Munich Agreement, the Sudetenland beca ...

) was a mathematician from Bohemia in

and later

Biography

Petr is known for the Petr–Douglas–Neumann theorem in plane geometry, which he proved in 1905 (in Czech) and in 1908 (in German). It was independently rediscovered by Jesse Douglas in 1940 and by B H Neumann in 1941. Eduard Čech was a doctoral student of Petr at Charles University in Prague. Petr's doctoral students also included Bohumil Bydžovský and Václav Hlavatý.

References

External links

* 1868 births 1950 deaths People from Kutná Hora District Czechoslovak mathematicians Mathematicians from Bohemia Charles University alumni Academic staff of Charles University Mathematicians from Austria-Hungary {{Scientist-stub