Consequences
The discovery of the Meissner effect led to the phenomenological theory of superconductivity by Fritz and Heinz London in 1935. This theory explained resistanceless transport and the Meissner effect, and allowed the first theoretical predictions for superconductivity to be made. However, this theory only explained experimental observations—it did not allow the microscopic origins of the superconducting properties to be identified. This was done successfully by the BCS theory in 1957, from which the penetration depth and the Meissner effect result.
-
A tin cylinder—in a Dewar flask filled with liquid helium—has been placed between the poles of an electromagnet. The magnetic field is about 8 milliteslas (80 G).
-
T=4.2 K, B=8 mT (80 G). Tin is in the normally conducting state. The compass needles indicate that magnetic flux permeates the cylinder.
-
The cylinder has been cooled from 4.2 K to 1.6 K. The current in the electromagnet has been kept constant, but the tin became superconducting at about 3 K. Magnetic flux has been expelled from the cylinder (the Meissner effect).
Read more about this topic: Meissner Effect
Famous quotes containing the word consequences:
“War is thus divine in itself, since it is a law of the world. War is divine through its consequences of a supernatural nature which are as much general as particular.... War is divine in the mysterious glory that surrounds it and in the no less inexplicable attraction that draws us to it.... War is divine by the manner in which it breaks out.”
—Joseph De Maistre (17531821)
“Every expansion of government in business means that government in order to protect itself from the political consequences of its errors and wrongs is driven irresistibly without peace to greater and greater control of the nations press and platform. Free speech does not live many hours after free industry and free commerce die.”
—Herbert Hoover (18741964)
“The horror of Gandhis murder lies not in the political motives behind it or in its consequences for Indian policy or for the future of non-violence; the horror lies simply in the fact that any man could look into the face of this extraordinary person and deliberately pull a trigger.”
—Mary McCarthy (19121989)