[What the heck is a "dormant" black hole. It either is or isn't a black hole I would think and once it's a black hole it stays a black hole.]
I thought the same thing. I am trying to picture a dormant tornado or hurricane. How does this work?
By "dormant" they mean that their is simply nothing
close enough at this time for the black hole to
grab in it's gravity hold....JJ61
"[What the heck is a "dormant" black hole. It either is or isn't a black hole I would think and once it's a black hole it stays a black hole.]
I thought the same thing. I am trying to picture a dormant tornado or hurricane. How does this work?"
A black hole that is not currently (or when viewed) pulling in any mass from outside to inside the vent horizon.
It is easy to infer the existence of a black hole, cygnus x-1, IIRC, is a good example. You have a star orbiting around in a tight orbit, clearly affected by a very dense, but unseen object. Nothing known could have that much mass (mass which is evident by it's effects on the orbiting bright star) except a black hole.
A star would just orbit around in a circle out in space for no reason, that type of motion infers a very, very dense, unseen object which has that start gravitationally locked in. Were that star to nudge close enough to the black hole, it too would pass the 'point of no return' and eventually get pulled inside the event horizon.