 |
| Titel |
The choice of the concept of magnetic field lines or of electric current lines: Alfvén medal lecture |
| VerfasserIn |
S.-I. Akasofu |
| Medientyp |
Artikel
|
| Sprache |
Englisch
|
| ISSN |
0992-7689
|
| Digitales Dokument |
URL |
| Erschienen |
In: Annales Geophysicae ; 29, no. 7 ; Nr. 29, no. 7 (2011-07-04), S.1215-1232 |
| Datensatznummer |
250017056
|
| Publikation (Nr.) |
 copernicus.org/angeo-29-1215-2011.pdf |
|
|
|
|
|
| Zusammenfassung |
| In 1967, at the Birkeland Symposium in Sandefjord, Norway, Professor Hannes
Alfvén stated that the second approach (in solving unsolved problems by the
standard MHD theory) to cosmic electrodynamics is to "thaw" the
"frozen-in" magnetic field lines. "We can illustrate essential properties
of the electromagnetic state of space either by depicting the magnetic field lines
or by depicting electric current lines," he said. There has been much
progress in space physics since the Birkeland Symposium more than 40 years
ago, but unfortunately our scientific community has not really succeeded in
thawing the frozen-in field lines. Instead, it has pursued magnetic
reconnection, a concept that Alfvén had been critical of. It is shown here
that we have to study many unsolved problems and problems thought to be
solved in terms of both the magnetic field line concept and the current system
concept. In taking Alfvén's approach, we must consider the whole system,
including the power supply (dynamo process) and its transmission and
distribution (electric currents) and observed phenomena (power dissipation
processes). Such a consideration can provide physical insight into many of
our unsolved problems and problems thought to be solved. In this paper, we
consider substorm onset processes, the substorm current system, sunspots,
solar flares, coronal mass ejections, the interplanetary current sheet, and
the magnetic field configuration of the heliosphere in terms of the current
system concept. In particular, it is shown that a study of the current
system is essential in substorm studies, more than changes of the magnetic
field configuration in the magnetotail. |
| |
|
| Teil von |
|
|
|
|
|
|
|
|