Edgar Krahn
Encyclopedia
Edgar Krahn was an Estonia
n mathematician
.
Krahn was born in Sootage, district Laiuse
, Estonia
, as a member of the Baltic German minority. He died in Rockville
, Maryland
, US
.
Krahn studied at the University of Tartu
and the University of Göttingen.
He graduated at Tartu in 1918, received his doctoral degree at Göttingen in 1926, with Richard Courant
as his advisor, and his habilitation
took place at Tartu in 1928.
He is co-author of the Rayleigh–Faber–Krahn inequality.
Krahn worked in Estonia, Germany
, the UK
, and the US in the following areas of pure
and applied
mathematics:
Estonia
Estonia , officially the Republic of Estonia , is a state in the Baltic region of Northern Europe. It is bordered to the north by the Gulf of Finland, to the west by the Baltic Sea, to the south by Latvia , and to the east by Lake Peipsi and the Russian Federation . Across the Baltic Sea lies...
n mathematician
Mathematician
A mathematician is a person whose primary area of study is the field of mathematics. Mathematicians are concerned with quantity, structure, space, and change....
.
Krahn was born in Sootage, district Laiuse
Laiuse
Laiuse is a small borough in Estonia. It is located in Jõgeva County and is a part of Jõgeva Parish. is one of the oldest in Estonia, being established in 1822. Laiuse is the location of the medieval Laiuse church. The church was first mentioned in 1319...
, Estonia
Estonia
Estonia , officially the Republic of Estonia , is a state in the Baltic region of Northern Europe. It is bordered to the north by the Gulf of Finland, to the west by the Baltic Sea, to the south by Latvia , and to the east by Lake Peipsi and the Russian Federation . Across the Baltic Sea lies...
, as a member of the Baltic German minority. He died in Rockville
Rockville, Maryland
Rockville is the county seat of Montgomery County, Maryland, United States. It is a major incorporated city in the central part of Montgomery County and forms part of the Baltimore-Washington Metropolitan Area. The 2010 U.S...
, Maryland
Maryland
Maryland is a U.S. state located in the Mid Atlantic region of the United States, bordering Virginia, West Virginia, and the District of Columbia to its south and west; Pennsylvania to its north; and Delaware to its east...
, US
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
.
Krahn studied at the University of Tartu
University of Tartu
The University of Tartu is a classical university in the city of Tartu, Estonia. University of Tartu is the national university of Estonia; it is the biggest and highest-ranked university in Estonia...
and the University of Göttingen.
He graduated at Tartu in 1918, received his doctoral degree at Göttingen in 1926, with Richard Courant
Richard Courant
Richard Courant was a German American mathematician.- Life :Courant was born in Lublinitz in the German Empire's Prussian Province of Silesia. During his youth, his parents had to move quite often, to Glatz, Breslau, and in 1905 to Berlin. He stayed in Breslau and entered the university there...
as his advisor, and his habilitation
Habilitation
Habilitation is the highest academic qualification a scholar can achieve by his or her own pursuit in several European and Asian countries. Earned after obtaining a research doctorate, such as a PhD, habilitation requires the candidate to write a professorial thesis based on independent...
took place at Tartu in 1928.
He is co-author of the Rayleigh–Faber–Krahn inequality.
Krahn worked in Estonia, Germany
Germany
Germany , officially the Federal Republic of Germany , is a federal parliamentary republic in Europe. The country consists of 16 states while the capital and largest city is Berlin. Germany covers an area of 357,021 km2 and has a largely temperate seasonal climate...
, the UK
United Kingdom
The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...
, and the US in the following areas of pure
Pure mathematics
Broadly speaking, pure mathematics is mathematics which studies entirely abstract concepts. From the eighteenth century onwards, this was a recognized category of mathematical activity, sometimes characterized as speculative mathematics, and at variance with the trend towards meeting the needs of...
and applied
Applied mathematics
Applied mathematics is a branch of mathematics that concerns itself with mathematical methods that are typically used in science, engineering, business, and industry. Thus, "applied mathematics" is a mathematical science with specialized knowledge...
mathematics:
- Differential geometry
- Differential equations
- Bausparmathematik, which is distantly related to insurance mathematicsActuarial scienceActuarial science is the discipline that applies mathematical and statistical methods to assess risk in the insurance and finance industries. Actuaries are professionals who are qualified in this field through education and experience...
- Probability theoryProbability theoryProbability theory is the branch of mathematics concerned with analysis of random phenomena. The central objects of probability theory are random variables, stochastic processes, and events: mathematical abstractions of non-deterministic events or measured quantities that may either be single...
- Gas dynamicsGas dynamicsGas dynamics is a branch of fluid dynamics concerned with studying the motion of gases and its consequent effects. Gas dynamics combines the principles of fluid mechanics and thermodynamics...
- Elasticity theory