Jørg Tofte Jebsen
Encyclopedia
Jørg Tofte Jebsen was a Norwegian physicist
who discovered and published an important theorem concerning general relativity
which is now known as Birkhoff's theorem
. This result was rediscovered by George David Birkhoff
a few years later.
Jebsen was born in a small town near Oslo
and majored in physics at the University of Oslo
. After graduate study in Berlin, where he worked on X-ray
s, he returned to Norway, worked on a master's degree in Oslo, and contemplated extending it to a Ph. D. At this time, Albert Einstein
's then new theory of gravitation, the general theory of relativity, was the subject of much enthusiasm among the graduate students, although the faculty was more cautious, apparently feeling out of their depth. Jebsen's thesis was on electrodynamics within Einstein's special theory and was referred to the closest thing they could find as an "outside expert" on relativity, Carl Wilhelm Oseen
at Uppsala University
.
Oseen, apparently sensing Jebsen's talent, pointed out some errors and asked Jebsen to resubmit his work after making improvements. This became Jebsen's master thesis. Furthermore, he was in 1919 invited to Uppsala by Oseen and it was here he started his work on general relativity and in particular his generalization of the Schwarzschild solution. The result was written up for publication in the spring of 1920. Unfortunately, Jebsen had been diagnosed with an aggressive case of the then chronic and fatal affliction of tuberculosis
. Seeking to prolong his life, he moved to Italy, where he died in 1922.
Oseen apparently sought to helped finance publication of the (German language) paper by the impoverished Jebsen, mentioned the theorem in his own 1921 English language review, and kept up a correspondence with the younger man until Jebsen's death. Despite Oseen's efforts, it seems that Jebsen's work sank like a stone and when the famous mathematician G. D. Birkhoff rediscovered and published the theorem in 1923 (without knowing of Jebsen's prior work), it was named for Birkhoff.
Physicist
A physicist is a scientist who studies or practices physics. Physicists study a wide range of physical phenomena in many branches of physics spanning all length scales: from sub-atomic particles of which all ordinary matter is made to the behavior of the material Universe as a whole...
who discovered and published an important theorem concerning general relativity
General relativity
General relativity or the general theory of relativity is the geometric theory of gravitation published by Albert Einstein in 1916. It is the current description of gravitation in modern physics...
which is now known as Birkhoff's theorem
Birkhoff's theorem (relativity)
In general relativity, Birkhoff's theorem states that any spherically symmetric solution of the vacuum field equations must be static and asymptotically flat. This means that the exterior solution must be given by the Schwarzschild metric....
. This result was rediscovered by George David Birkhoff
George David Birkhoff
-External links:* − from National Academies Press, by Oswald Veblen....
a few years later.
Jebsen was born in a small town near Oslo
Oslo
Oslo is a municipality, as well as the capital and most populous city in Norway. As a municipality , it was established on 1 January 1838. Founded around 1048 by King Harald III of Norway, the city was largely destroyed by fire in 1624. The city was moved under the reign of Denmark–Norway's King...
and majored in physics at the University of Oslo
University of Oslo
The University of Oslo , formerly The Royal Frederick University , is the oldest and largest university in Norway, situated in the Norwegian capital of Oslo. The university was founded in 1811 and was modelled after the recently established University of Berlin...
. After graduate study in Berlin, where he worked on X-ray
X-ray
X-radiation is a form of electromagnetic radiation. X-rays have a wavelength in the range of 0.01 to 10 nanometers, corresponding to frequencies in the range 30 petahertz to 30 exahertz and energies in the range 120 eV to 120 keV. They are shorter in wavelength than UV rays and longer than gamma...
s, he returned to Norway, worked on a master's degree in Oslo, and contemplated extending it to a Ph. D. At this time, Albert Einstein
Albert Einstein
Albert Einstein was a German-born theoretical physicist who developed the theory of general relativity, effecting a revolution in physics. For this achievement, Einstein is often regarded as the father of modern physics and one of the most prolific intellects in human history...
's then new theory of gravitation, the general theory of relativity, was the subject of much enthusiasm among the graduate students, although the faculty was more cautious, apparently feeling out of their depth. Jebsen's thesis was on electrodynamics within Einstein's special theory and was referred to the closest thing they could find as an "outside expert" on relativity, Carl Wilhelm Oseen
Carl Wilhelm Oseen
Carl Wilhelm Oseen was a theoretical physicist in Uppsala and Director of the Nobel Institute for Theoretical Physics in Stockholm....
at Uppsala University
Uppsala University
Uppsala University is a research university in Uppsala, Sweden, and is the oldest university in Scandinavia, founded in 1477. It consistently ranks among the best universities in Northern Europe in international rankings and is generally considered one of the most prestigious institutions of...
.
Oseen, apparently sensing Jebsen's talent, pointed out some errors and asked Jebsen to resubmit his work after making improvements. This became Jebsen's master thesis. Furthermore, he was in 1919 invited to Uppsala by Oseen and it was here he started his work on general relativity and in particular his generalization of the Schwarzschild solution. The result was written up for publication in the spring of 1920. Unfortunately, Jebsen had been diagnosed with an aggressive case of the then chronic and fatal affliction of tuberculosis
Tuberculosis
Tuberculosis, MTB, or TB is a common, and in many cases lethal, infectious disease caused by various strains of mycobacteria, usually Mycobacterium tuberculosis. Tuberculosis usually attacks the lungs but can also affect other parts of the body...
. Seeking to prolong his life, he moved to Italy, where he died in 1922.
Oseen apparently sought to helped finance publication of the (German language) paper by the impoverished Jebsen, mentioned the theorem in his own 1921 English language review, and kept up a correspondence with the younger man until Jebsen's death. Despite Oseen's efforts, it seems that Jebsen's work sank like a stone and when the famous mathematician G. D. Birkhoff rediscovered and published the theorem in 1923 (without knowing of Jebsen's prior work), it was named for Birkhoff.