Theory of magnetars

The discovery of long periods and high period derivatives in soft gamma-ray repeaters (SGRs) over the past year has raised the possibility that magnet ars, neutron stars having magnetic fields above 10(14) G, may be real astro physical objects. Magnetars are possibly the first astrophysical sources to derive their primary radiation power from magnetic energy,which substantia lly exceeds their rotational energy. In addition, the physics of supercriti cal magnetic fields operates in a more exotic realm than even that of norma l pulsars. I will discuss acceleration and radiation models for the SGR. bu rsts and quiescent emission from SGRs and anomalous X-ray pulsars.