The Nature of the Compact X-Ray Source in Supernova Remnant RCW 103

The discovery of the 6.67 hr periodicity in the X-ray source 1E 161348-5055 associated with the supernova remnant RCW 103 has raised interesting questions about the nature of the X-ray source. Here we argue that in either accreting neutron star or magnetar model, a supernova fallback disk may be a critical ingredient in theoretical interpretations of 1E 161348-5055. We further emphasize the effect of fallback disks on the evolution of young compact objects in various ways and suggest that even SS 433 could also be powered by a fallback disk accretion process.