Blackett effect
Encyclopedia
The Blackett effect, also called gravitational magnetism, is the hypothetical generation of a magnetic field
by an uncharged, rotating body. This effect has never been observed.
-British
physicist
Arthur Schuster
as an explanation for the magnetic field
of the Earth
, but was found nonexistent in a 1923 experiment by H. A. Wilson. The hypothesis was revived by the British
physicist
P. M. S. Blackett in 1947 when he proposed that a rotating body should generate a magnetic field proportional to its angular momentum
. This was never generally accepted, and by the 1950s even Blackett felt it had been refuted., pp. 39–43
The Blackett effect was used by the science fiction
writer James Blish
in his series Cities in Flight
(1955–1962) as the basis for his fictional stardrive
, the spindizzy
.
Magnetic field
A magnetic field is a mathematical description of the magnetic influence of electric currents and magnetic materials. The magnetic field at any given point is specified by both a direction and a magnitude ; as such it is a vector field.Technically, a magnetic field is a pseudo vector;...
by an uncharged, rotating body. This effect has never been observed.
History
Gravitational magnetism was proposed by the GermanGermany
Germany , officially the Federal Republic of Germany , is a federal parliamentary republic in Europe. The country consists of 16 states while the capital and largest city is Berlin. Germany covers an area of 357,021 km2 and has a largely temperate seasonal climate...
-British
United Kingdom
The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...
physicist
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...
Arthur Schuster
Arthur Schuster
Sir Franz Arthur Friedrich Schuster FRS was a German-born British physicist known for his work in spectroscopy, electrochemistry, optics, X-radiography and the application of harmonic analysis to physics...
as an explanation for the magnetic field
Magnetic field
A magnetic field is a mathematical description of the magnetic influence of electric currents and magnetic materials. The magnetic field at any given point is specified by both a direction and a magnitude ; as such it is a vector field.Technically, a magnetic field is a pseudo vector;...
of the Earth
Earth
Earth is the third planet from the Sun, and the densest and fifth-largest of the eight planets in the Solar System. It is also the largest of the Solar System's four terrestrial planets...
, but was found nonexistent in a 1923 experiment by H. A. Wilson. The hypothesis was revived by the British
United Kingdom
The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...
physicist
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...
P. M. S. Blackett in 1947 when he proposed that a rotating body should generate a magnetic field proportional to its angular momentum
Angular momentum
In physics, angular momentum, moment of momentum, or rotational momentum is a conserved vector quantity that can be used to describe the overall state of a physical system...
. This was never generally accepted, and by the 1950s even Blackett felt it had been refuted., pp. 39–43
The Blackett effect was used by the science fiction
Science fiction
Science fiction is a genre of fiction dealing with imaginary but more or less plausible content such as future settings, futuristic science and technology, space travel, aliens, and paranormal abilities...
writer James Blish
James Blish
James Benjamin Blish was an American author of fantasy and science fiction. Blish also wrote literary criticism of science fiction using the pen-name William Atheling, Jr.-Biography:...
in his series Cities in Flight
Cities in Flight
Cities in Flight is an omnibus volume of four novels written by James Blish, originally published between 1955 and 1962, which became known over time collectively as the 'Okie' novels. The novels feature entire cities that are able to fly through space using an anti-gravity device, the spindizzy...
(1955–1962) as the basis for his fictional stardrive
Inertialess drive
The inertialess drive is a fictional means of accelerating to close to the speed of light or faster-than-light travel, originally used in Triplanetary and the Lensman series by E.E. "Doc" Smith, and later by Robert A...
, the spindizzy
Spindizzy
The Dillon-Wagoner Graviton Polarity Generator, known colloquially as the spindizzy is a fictitious anti-gravity device imagined by James Blish for his series Cities in Flight...
.