Friday 29 May 2015

30-MAY-1908 :- Birth Of Hannes Alfvén , Nobel Prize winner.

Hannes Olof Gösta Alfvén 
( 30 May 1908 – 2 April 1995) was a Swedish electrical engineerplasma physicist and winner of the 1970 Nobel Prize in Physics for his work on magneto hydro dynamics (MHD). He described the class of MHD waves now known as Alfvén waves. He was originally trained as an electrical power engineer and later moved to research and teaching in the fields of plasma physics and electrical engineering. Alfvén made many contributions to plasma physics, including theories describing the behavior of aurorae, the Van Allen radiation belts, the effect of magnetic storms on the Earth's magnetic field, the terrestrial magnetosphere, and the dynamics of plasmas in the Milky Way galaxy.

In 1937, Alfvén argued that if plasma pervaded the universe, it could then carry electric currents capable of generating a galactic magnetic field. After winning the Nobel Prize for his works in magneto hydro dynamics, he emphasized that:
"In order to understand the phenomena in a certain plasma region, it is necessary to map not only the magnetic but also the electric field and the electric currents. Space is filled with a network of currents which transfer energy and momentum over large or very large distances. The currents often pinch to filamentary or surface currents. The latter are likely to give space, as also interstellar and intergalactic space, a cellular structure."
His theoretical work on field-aligned electric currents in the aurora (based on earlier work by Kristian Birkeland) was confirmed in 1967, these currents now being known as Birkeland currents.
Alfvén's work was disputed for many years by the senior scientist in space physics, the British mathematician and geophysicist Sydney Chapman. Alfvén's disagreements with Chapman stemmed in large part from trouble with the peer review system. Alfvén rarely benefited from the acceptance generally afforded senior scientists in scientific journals. He once submitted a paper on the theory of magnetic storms and auroras to the American journal Terrestrial Magnetism and Atmospheric Electricity only to have his paper rejected on the ground that it did not agree with the theoretical calculations of conventional physics of the time. He was regarded as a person with unorthodox opinions in the field by many physicists, R. H. Stuewer noting that "... he remained an embittered outsider, winning little respect from other scientists even after he received the Nobel Prize..."and was often forced to publish his papers in obscure journals. Alfvén recalled:
"When I describe the [plasma phenomena] according to this formulism most referees do not understand what I say and turn down my papers. With the referee system which rules US science today, this means that my papers are rarely accepted by the leading US journals.'

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