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Consider a feeding, growing black hole. We never observe any matter to cross the event horizon, because time stops there. All matter would be "stuck" in a sphere around the event horizon, slowly approaching it, but it would take an infinite amount of time to actually reach it. On the other hand a black hole can grow in size in a finite amount of time if we feed it. So while particles are "stuck" just outside the event horizon, the event horizon itself will "cross" these particles. Would these particles end-up inside the event horizon? What would happen to them? Which direction would they move or would they stand still at the position they encountered the event horizon?