Extreme variability in quasars

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I am studying extreme variability in quasars. Quasars are the most luminous objects in the universe, and in some cases their brightness can vary by an order of magnitude on timescales of months. There are a number of mechanisms that could cause this activity and I am focusing on one such mechanism - tidal disruption events (TDEs). This is when a star gets ripped apart by the tidal forces of the supermassive black hole that powers the quasar, temporarily causing a huge increase in mass falling onto the black hole. This leads to a flare up which we can observe. Studying these extreme events provides a unique testbed for physics in the region close to the central black hole and for accretion physics in general, which, though poorly understood, is relevant to a number of astrophysical phenomena.