it attrackts light and deforms the time-space continuum. why are you guys questionning proven physical theories? large black holes such as quasars have an extremely long lifespan. this is due to their giantic mass. a black hole loses mass through hawking radiation, which is emitted from the event horizon (no radiation can escape gravity from within the event horizon). when the hole has lost all its mass, it will simply disappear. the smaller the hole, the faster it will collaps due to weight loss. so, this tiny little hole will of course be very dangerous with its lifespan of some nanoseconds.