Editing Magnetic reconnection (section)

=== Physical interpretation ===
The qualitative description of the reconnection process is such that [[magnetic field lines]] from different magnetic domains (defined by the field line connectivity) are spliced to one another, changing their patterns of connectivity with respect to the sources.  It is a violation of an approximate conservation law in plasma physics, called [[Alfvén's theorem]] (also called the "frozen-in flux theorem") and can concentrate mechanical or magnetic energy in both space and time. Solar flares, the largest explosions in the [[Solar System]], may involve the reconnection of large systems of magnetic flux on the [[Sun]], releasing, in minutes, energy that has been stored in the magnetic field over a period of hours to days.  Magnetic reconnection in [[Earth]]'s [[magnetosphere]] is one of the mechanisms responsible for the [[Aurora (astronomy)|aurora]], and it is important to the science of controlled [[nuclear fusion]] because it is one mechanism preventing [[magnetic confinement]] of the fusion fuel.

In an electrically conductive [[Plasma (physics)|plasma]], magnetic field lines are grouped into 'domains'— bundles of field lines that connect from a particular place to another particular place, and that are topologically distinct from other field lines nearby.  This topology is approximately preserved even when the magnetic field itself is strongly distorted by the presence of variable currents or motion of magnetic sources, because effects that might otherwise change the magnetic topology instead induce [[eddy current]]s in the plasma; the eddy currents have the effect of canceling out the topological change.