Slow uniform rotation reduces the critical adiabatic exponent for the stability of gaseous stars

Abstract: We prove that any sufficiently slow uniform rotation stabilizes the supermassive star under axi-symmetric perturbations, and the stability persists for every adiabatic exponent in a left neighborhood of the mass-critical one. The key new ingredient of the linear analysis is a structural property of the self-similar family inherited from the mass-critical scaling: the associated self-similar direction becomes a reduced kernel direction of a modified linearized operator.