Magnetorotational Instability in Accretion Disks

Zoom into a local co-rotating patch of an accretion disk around a black hole and watch the magnetorotational instability (MRI) at work — the Balbus-Hawley mechanism that lets a weak magnetic field turn smooth Keplerian shear into exponentially growing turbulence. Tune the magnetic field strength and perturbation wavelength to move through the instability's growth-rate curve, find the fastest-growing mode at k·v_A ≈ Ω where the growth rate peaks at the rigorous value (3/4)Ω, and see live readouts for growth rate, perturbation amplitude and the resulting outward angular-momentum transport that drives real accretion.