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Hannes Alfvén

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File:Hannes-alfven.jpg
Hannes Alfvén (1908-1995), winning the Nobel Prizing for his work on magnetohydrodynamics [1].

Hannes Olof Gösta Alfvén (May 30, 1908; Norrköping, Sweden - April 2, 1995; Djursholm, Sweden) is known as a Swedish plasma physicist who won the Nobel Prize in 1970 for his work developing magnetohydrodynamics theory. He trained as, and considered himself to be, an electrical power engineer, taught physics at university, became professor of electromagnetic theory, and accepted the Chair of Plasma Physics. Later he worked in universities in America. He died aged 86 years old.

Introduction

Considered an outsider and a heretic by many of his peers, the engineer made significant contributions to plasma physics, including the aurorae, Van Allen radiation belts, the effect of magnetic storms on the Earth's magnetic field, the magnetosphere, the formation of comet tails, the formation of the solar system, and the dynamics of plasmas in our galaxy (plasma cosmology).

In 1937, when interstellar space was thought to be a vacuum and consequently unable to support an electrical current, he argued that if plasma pervaded the universe, then it could carry electric currents that could generate a galactic magnetic field. After winning his Nobel Prize for magnetohydrodynamics, it is said that he spent the rest of his life trying to convince scientists that magnetic fields were only half the story, and that electric currents played a more significant role in the universe. In 1974, his theoretical work on field-aligned electric currents in the aurora, based on earlier work by Kristian Birkeland, was confirmed by satellite, and Birkeland currents were discovered. Plasma Cosmology, an alternative theory to the Big Bang, is based on Alfvén's work.

Education

Alfvén received a PhD from the University of Uppsala in 1934. His thesis was entitled "Investigations of the Ultra-short Electromagnetic Waves."

Early years

In 1934, he taught physics at both the University of Uppsala and the Nobel Institute for Physics in Stockholm. In 1940, he became professor of electromagnetic theory and electrical measurements at the Royal Institute of Technology in Stockholm. In 1945, he acquired the nonappointive Chair of Electronics at Royal Institute of Technology in Stockholm. It was changed to a Chair of Plasma Physics in 1963. In 1967, after leaving Sweden and spending some time in the Soviet Union, he moved to America. He worked in the departments of electrical engineering at two universities, the University of California, San Diego and the University of Southern California.

Alfvén considered himself an electrical power engineer. During his scientific career, prior to winning the Nobel Prize, Alfvén was not generally recognized as a leading innovator in the scientific community (though they were using his work). He enjoyed the assertion that he was guilty of a fault or offence by the entry into areas not previously explored in astrophysics leveled by other cosmologists and theoreticians.

Research, awards, and contributions

His work was continuously disputed for many years by the senior scientist in space physics, the British-American geophysicist Sydney Chapman. Alfvén had trouble with the peer review system. He did not in any circumstance benefit without volition the acceptance generally afforded senior scientists in scientific journals. Alfvén once submitted a paper on the theory of magnetic storms and auroras to the leading American journal Terrestrial Magnetism and Atmospheric Electricity and the paper was 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. He was often forced to publish his papers in obscure journals.

He was awarded the Nobel Prize in Physics in 1970 for his work with magnetohydrodynamics (MHD). In 1988, Alfvén was awarded by the American Geophysical Union the Bowie medal, for his work on comets and plasmas in the solar system.

Awards

File:NGC 6543 outer halo.jpg
In 1963, Alfvén predicted large scale filamentary structure of the universe, and suggested that such filaments, such as the ones seen here around the Cat's Eye Nebula, were Birkeland Currents

Alfvén has also been awarded:

Gold Medal of the Royal Astronomical Society (1967)
Gold Medal of the Franklin Institute (1971)
Lomonosov Gold Medal of the USSR Academy of Sciences (1971)

Memberships

Academies and institutes with Alfvén in their membership:

Royal Swedish Academy of Sciences
Royal Swedish Academy of Engineering Sciences
Institute of Electrical and Electronics Engineers (life fellow)
European Physical Society
American Academy of Arts and Sciences
Yugoslav Academy of Sciences
Pugwash Conferences on Science and World Affairs

A creative and intuitive intellect of the 20th century, Alfvén was one of the few scientists who was a foreign member of both the U.S. and Soviet Academies of Sciences.

Developed and researched

He played a central role in the development of:

Plasma physics
Charged particle beams
Interplanetary physics
Magnetospheric physics
Magnetohydrodynamics
Solar phenomena investigation (such as the solar wind)
Aurorae science

In 1939, Alfvén proposed the theory of magnetic storms and auroras and the theory of plasma dynamics in the earth's magnetosphere. Electric charges spiraling in magnetic fields caused the motions of electrons and ions.

Applications of his research in space science include:

Van Allen radiation belt explanations
Earth's magnetic field reduction during magnetic storms
Magnetosphere (protective plasma covering the earth)
Formation of comet tails
Formation of the solar system
Dynamics of plasmas in the galaxy
Fundamental nature of the universe

Alfvén conducted interplanetary and magnetospheric physics research.

Alfvén's views followed the founder of magnetospheric physics, Kristian Birkeland. At the end of the nineteenth century, Birkeland proposed (backed by extensive data) that electric currents flowing down along the earth's magnetic fields into the atmosphere caused of the aurora and polar magnetic disturbances.

Alfvén's contributions helped develop:

Particle beam accelerators
Controlled thermonuclear fusion
Hypersonic flight
Rocket propulsion
Reentry braking of space vehicles

Alfvén's contributions to astrophysics:

Galactic magnetic field forms - Cosmic Magnetism (1937)
Identify nonthermal radiation (synchrotron radiation) from astronomical sources (1950)

In 1963, Alfvén first predicted the large scale filamentary structure of the universe based on his experience of the filamentary nature of plasma. This discovery perplexed astrophysicists in 1991.

Alfvén waves (low frequency hydromagnetic plasma oscillations) are named in his honor. Many of his theories about the solar system have been verified as late as the 1980's through measurements of cometary and planetary magnetospheres by satellites and probes. Alfvén's theories gained acceptance only two or three decades after their publication. He is also known for developing plasma cosmology, a non-standard alternative to the big bang. Among physicists today, there is a general lack of awareness of some of Alfvén's contributions to fields of plasma physics (eg. the electric field description of plasmas, Birkeland currents, plasma circuits), and his ideas have routinely been used without recognition (eg. see the History of the discover of Birkeland currents, and Stephen G. Brush's article "Alfvén's Programme in Solar System Physics" (IEEE Trans. Plasma Science, Vol. 20 No. 6, Dec 1992).).

Alfvén versus the Big Bang

Alfvén and colleagues proposed an alternative cosmological theory, the Alfvén-Klein model to both the Steady State and the Big Bang cosmologies. There is also an Ambiplasma version. Alfvén believed the problem with the Big Bang was that astrophysicists tried to extrapolate the origin of the universe from mathematical theories developed on the blackboard. The Big Bang was a myth according to Alfvén. This myth was devised to explain creation according to Alfvén. He confided with close friends that he felt the theory tried to make science compatible with the authoritative religious declaration of creatio ex nihilo or creation out of nothing.

Alfvén proposed a "plasma universe". This theory is called Plasma cosmology and after receiving a cold reception in the wider scientific community, stated that he thought 'the theory may take time to be accepted by the popular consciousness'.

Later years

In 1991, Alfvén retired his posts of professor of electrical engineering at the University of California, San Diego and professor of plasma physics at the Royal Institute of Technology in Stockholm .

Alfvén spent his life alternating between California and Sweden. He died when he was 86 years old.

The asteroid 1778 Alfvén was named in his honour.

Personal life

Alfvén had a good sense of humor and he participated in a variety of social issues and worldwide disarmament movements. He had a long-standing distrust of computers. Alfvén studied the history of science and oriental philosophy and religion. He spoke Swedish, English, German, French, and Russian, and some Spanish and Chinese.

Hannes Alfvén was married for 67 years to Kirsten. They raised five children, one boy and four girls. The son became a physician. One daughter became a writer in Sweden and one a lawyer.

Alfvén wrote popular science books:

Worlds-Antiworlds: Antimatter in Cosmology (1966)
The Great Computer: A Vision (1968) (a political-scientific satire under the pen name: Olof Johannesson, publ. Gollancz, ISBN 05750-0059-7)
Atom, Man, and the Universe: A Long Chain of Complications (1969)
Living on the Third Planet (1972).

Obituary

Online Bibliography

File:Alfven-book-covers.jpg
Hannes Alfvén's seminal books, Cosmic Plasma (1981) and Cosmical Electrodynamics (1963, co-authored with Carl-Gunn Fälthammar)

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