how can there be a black hole in all galaxies?

if there is a black hole in the centre of all galaxies, does that mean that eventually all matter in the universe will be sucked in to these and there will be nothing left?

if there is a black hole in the centre of all galaxies, does that mean that eventually all matter in the universe will be sucked in to these and there will be nothing left?

nothing but blackholes that is. Then they will evaporate and there will just be big seas of nothingness. At least that's our current best guess.

Rather depressing but there you have it!

what about the jets of particles that shoot out from black holes when their anti particle is pulled over the event horizon? will the universe just be filled with a pile of particles floating around? also, what happens to matter in a black hole? does it simply disappear, squashed into nothingness?

what about the jets of particles that shoot out from black holes when their anti particle is pulled over the event horizon? will the universe just be filled with a pile of particles floating around? also, what happens to matter in a black hole? does it simply disappear, squashed into nothingness?

I've never heard of the jets being caused by anti-particles. Our universe is pretty much exclusively matter so there are no anti-particles around! The jets are a result of the conservation of angular momentum. These should ensure that not all matter is swallowed up but there would be very little left and it would not be dense enough to form stars or galaxies.

The matter in a black hole does not cease to exist. If it did then a black hole would not have the huge gravity that it does. Over time matter actually leaks out of a black hole via a form of quantum tunneling called Hawking Radiation. So, in effect blackholes evaporate over billions of years.

Now, as to what happens in the longer term it all comes down to the rate of expansion of the universe. If there is enough matter in the universe all the black holes will get pulled into each other and reverse the expansion of the universe and basically cause a 'big crunch', if on the other hand there is not enough matter in the universe to slow and reverse the expansion then the universe will expand so rapidly that the stuff that evaporates from the blackholes will be spread out so thinly that the whole universe will essentially become empty. The latter is what current measurements of the expansion seem to be implying.

Nobody really knows whats in the centre of a black hole.
Our knowledge of Physics breaks down at a "singularity".
It'll probably take a "new physics" to explain it.

Anyway new physics comes along every few centuries and all the rules are re-written.

In a thousand years time it will all be tame stuff which we "ancients" were too thick to understand !

to explain the jets of particles, from my understanding, particles are just "appearing" in the universe all the time, but these particles and their antiparticles obliterate eachother, and so its as if they dont exist, but at a black hole, some of the anti particles get sucked over the event horison , leaving the particles as they wont get obliterated by their opposite. these particles are then spewed out of the black hole by this angular momentum. thats how i understand it. and this is what is hawking radiation.