The abrupt reconnection of magnetic flux lines embedded in plasmas is an important mechanism for transferring energy from the magnetic field to the motion of plasma particles. Magnetic reconnection manifests itself spectacularly on diverse scales: solar flares, auroras from the penetration of solar wind into Earth’s magnetosphere, and containment failures in laboratory tokamaks. And reconnection is suspected in neutron-star quakes, gamma-ray bursts, and jet formation in black-hole accretion disks.
When there’s magnetic field in a plasma, the cyclotron gyration of electrons and ions effectively binds them to individual flux lines. The result is that the field lines are generally frozen into the plasma, riding along with its bulk motion. For example, in the solar wind—a plasma of electrons and ions (mostly protons) from the Sun—embedded magnetic field lines ride Earthward at several hundred kilometers per second.
Magnetic reconnection is a striking exception to the general plasma picture of frozen-in field...
