Physics of modes in a differentially rotating system -analysis of the shearing sheet

An analysis is given of the linear non-vortical modes of the shearing sheet, a model compressible two-dimensional fluid system with constant density, constant shear, and Coriolis force. This model has several features found in differentially rotating systems of interest in astrophysics, such as disc galaxies, accretion tori, planetary rings, protostellar nebulae, and possibly even rotating stars. (author)