The paper “The stability of a radially stretching disc beneath a uniformly rotating fluid” co-authored by Matt Turner and Patrick Weidman (University of Colorado) has been accepted for publication in Physical Review Fluids. The paper investigates the temporal and absolute instability properties for a flow that consists of a radially stretching plate under a rigidly rotating flow at a constant angular velocity.  In particular the results in the paper show that a stretching plate tends to stabilize the flow while a shrinking plate destabilizes it.  Full abstract available on the PRF website here. The figure below from the paper shows a schematic of the flow field.