Like a rotating planet bulging at the equator, the sphere deforms into a squashed spheroid depending on its rotation. Explaining this deformation requires external causes in a frame of reference in the spheroid it is not rotating, and these external causes may be taken as "absolute rotation" in classical physics and special relativity.[1] In general relativity no external causes are invoked. The rotation is relative to the local geodesics, and since the local geodesics eventually channel information from the distant stars, there appears to be absolute rotation relative to these stars.[2]