Table 'celebmem_joomla.jos_Stalytics_config' doesn't exist SQL=SELECT name,value FROM jos_Stalytics_configTable 'celebmem_joomla.jos_Stalytics_config' doesn't exist SQL=SELECT name,value FROM jos_Stalytics_configTable 'celebmem_joomla.jos_Stalytics_config' doesn't exist SQL=SELECT name,value FROM jos_Stalytics_configTable 'celebmem_joomla.jos_Stalytics_bots' doesn't exist SQL=SELECT SQL_BIG_RESULT bot_string as _string, bot_name as _name FROM jos_Stalytics_bots ORDER BY idTable 'celebmem_joomla.jos_Stalytics_visitors_count' doesn't exist SQL=INSERT INTO jos_Stalytics_visitors_count (hour, year_day, month_day, week_day, week, month, year,stamp) VALUES (HOUR(FROM_UNIXTIME(1513416099)),DAYOFYEAR(FROM_UNIXTIME(1513416099)), DAYOFMONTH(FROM_UNIXTIME(1513416099)), DAYOFWEEK(FROM_UNIXTIME(1513416099)), WEEK(FROM_UNIXTIME(1513416099),1),MONTH(FROM_UNIXTIME(1513416099)), YEAR(FROM_UNIXTIME(1513416099)),FROM_UNIXTIME(1513416099))Table 'celebmem_joomla.jos_Stalytics_provider_count' doesn't exist SQL=INSERT INTO jos_Stalytics_provider_count (provider_name,month_day,month,year,visit_date) VALUES ("compute-1.amazonaws.com",DAYOFMONTH(NOW()),MONTH(NOW()),YEAR(NOW()),CURDATE())Table 'celebmem_joomla.jos_Stalytics_visitors' doesn't exist SQL=INSERT into jos_Stalytics_visitors (session_id,start_time,ip,host,language,country, os,browser,is_robot,referer,phrases_words, number_of_PI, last_action,referrerFullPath) VALUES('0f4098a8890a6db8de5ea739b7451c84',NOW(),'54.227.51.103','compute-1.amazonaws.com','','', '','', 0,'','', 1, NOW(), '')Table 'celebmem_joomla.jos_Stalytics_PI_count' doesn't exist SQL=INSERT INTO jos_Stalytics_PI_count (site_name,month_day,month,year,visit_date) VALUES ("Hannes Alfvén 1908-1995 - celebmemorial.com",DAYOFMONTH(NOW()),MONTH(NOW()),YEAR(NOW()),CURDATE()) Table 'celebmem_joomla.jos_Stalytics_visitors_recurrent_count' doesn't exist SQL=INSERT INTO jos_Stalytics_visitors_recurrent_count (visit_date) VALUES (CURDATE())Table 'celebmem_joomla.jos_Stalytics_config' doesn't exist SQL=SELECT name,value FROM jos_Stalytics_config
A
B
C
D
E
F
G
H
I
J
K
L
M
N
O
P
Q
R
S
T
U
V
W
X
Y
Z
You are here:

H » H » Celebrities


Hannes Alfvén 1908-1995
 


Country : Physicist
Profession : Norrköping, Sweden
Date of birth : 1908-05-30
Date of death : 1995-04-02
Cause of Death : Unspecified

Warning: simplexml_load_file(http://gdata.youtube.com/feeds/base/videos?q=Hannes+Alfv%C3%A9n&client=ytapi-youtube-search&v=2) [function.simplexml-load-file]: failed to open stream: HTTP request failed! HTTP/1.0 410 Gone in /home/celebmem/public_html/components/com_content/views/article/tmpl/default.php on line 151

Warning: simplexml_load_file() [function.simplexml-load-file]: I/O warning : failed to load external entity "http://gdata.youtube.com/feeds/base/videos?q=Hannes+Alfv%C3%A9n&client=ytapi-youtube-search&v=2" in /home/celebmem/public_html/components/com_content/views/article/tmpl/default.php on line 151

256px-Hannes-alfvenportrait

Hannes Olof Gösta Alfvén (30 May 1908; Norrköping, Sweden – 2 April 1995; Djursholm, Sweden) was a Swedish plasma physicist and Nobel laureate for his work on the theory of magnetohydrodynamics. He was originally trained as an electrical power engineer and later moved to research and teaching in the fields of plasma physics. 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.

Biography

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 magnetohydrodynamics, 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 by satellite observations, in 1974, resulting in the discovery of Birkeland currents.

Education

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

Early years

In 1934, Alfvén taught physics at both the University of Uppsala and the Nobel Institute for Physics in Stockholm, Sweden. 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 position of Chair of Electronics. His title was changed to Chair of Plasma Physics in 1963. In 1954-1955, Alfvén was a Fulbright Scholar at the University of Maryland, College Park. In 1967, after leaving Sweden and spending time in the Soviet Union, he moved to the United States. Alfvén worked in the departments of electrical engineering at both the University of California, San Diego and the University of Southern California.

Alfvén considered himself an electrical engineer foremost. 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.[citation needed]

Research, awards, and contributions

Alfvén's work was disputed for many years by the senior scientist in space physics, the British-American 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 and his 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, 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.

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

Awards

Alfvén was also 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

  • 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
  • International Academy of Science

Alfvén was one of the few scientists who was a foreign member of both the United States and Soviet Academies of Sciences.

Research

Alfvén 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.

Applications of Alfvén's research in space science include:

  • Van Allen radiation belt theory
  • Reduction of the Earth's magnetic field 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's views followed those of 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 the aurora and polar magnetic disturbances.

Areas of technology benefiting from Alfvén's contributions include:

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

Contributions to astrophysics:

  • Galactic magnetic field (1937)
  • Identified nonthermal synchrotron radiation from astronomical sources (1950)

Alfvén waves (low frequency hydromagnetic plasma oscillations) are named in his honor. Many of his theories about the solar system were verified as late as the 1980s through external measurements of cometary and planetary magnetospheres. But Alfvén himself noted that astrophysical textbooks poorly represented known plasma phenomena:

A study of how a number of the most used textbooks in astrophysics treat important concepts such as double layers, critical velocity, pinch effects, and circuits is made. It is found that students using these textbooks remain essentially ignorant of even the existence of these concepts, despite the fact that some of them have been well known for half a century (e.g, double layers, Langmuir, 1929; pinch effect, Bennet, 1934).

Alfvén reported that of 17 of the most used textbooks on astrophysics, none mention the pinch effect, none mentioned critical ionization velocity, only two mentioned circuits, and three mentioned double layers.

Alfvén's cosmological model

Main article: plasma cosmology

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, rather than starting from known observable phenomena. He also considered the Big Bang to be a scientific myth devised to explain creation.

Alfvén and colleagues proposed the Alfvén-Klein model as an alternative cosmological theory to both the Big Bang and steady state theory cosmologies.

Later years

In 1991, Alfvén retired as 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 adult life alternating between California and Sweden. He died at the age of 86.

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, oriental philosophy, and religion. He spoke Swedish, English, German, French, and Russian, and some Spanish and Chinese. He expressed great concern about the difficulties of permanent high-level radioactive waste management." Alfvén was also interested in problems in cosmology and all aspects of auroral physics, and used Schröder's well known book on aurora, Das Phänomen des Polarlichts. Letters of Alfvén, Treder, and Schröder were published on the occasion of Treder's 70th birthday. A long paper on changes in auroral theories was published by Wilfried Schröder in honor of Hannes Alfvén's 80th birthday in the German scientific journal Gerlands Beiträge zur Geophysik in 1988. The relationships between Hans-Jürgen Treder, Hannes Alfvén and Wilfried Schröder were discussed in detail by Schröder in his publications.

Alfvén was married for 67 years to his wife Kerstin. They raised five children, one boy and four girls. His son became a physician, while one daughter became a writer and another a lawyer in Sweden. The composer Hugo Alfvén was Hannes Alfvén's uncle.

Bibliography

Full List

  • Cosmical Electrodynamics, International Series of Monographs on Physics, Oxford: Clarendon Press, 1950. (See also 2nd Ed. 1963, co-authored with Carl-Gunne Fälthammar)
  • 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).
  • Cosmic Plasma, Astrophysics and Space Science Library, Vol. 82 (1981) Springer Verlag. ISBN 90-277-1151-8
  • Schröder, Wilfried, and Hans Jürgen Treder. 2007. Theoretical physics and geophysics: Recollections of Hans-Jürgen Treder (1928 - 2006). Potsdam: Science Editions.

Comments (0)Add Comment

Write comment

security code
Write the displayed characters


busy