Black Holes What will happen?

[Dicer]

So I know there are a ton of theories about black holes and how there made and what they do but i was wondering about something that is bothering me. I came to this Question just by chance. I was watching the science channel and it was a episode about the big bang and how everything started. After that show was an episode on black holes. Anyways here is my question. If the universe started at singularity and black holes suck up everything into singularity. Would that not mean that black holes will eventually suck up the entire universe into singularity again? Ultimately starting the universe all over again with a big bang? This could be way of base but or just another crazy theory. Let me know what you think?

 

[MeteorWayne]

No black holes don't suck anything other than by their gravitational effect. Sure some are very massive, but they are just objects with a certain amount of mass like anything else in the Universe.

 

[sacr3]

No black holes don't suck anything other than by their gravitational effect. Sure some are very massive, but they are just objects with a certain amount of mass like anything else in the Universe.

Lets assume a massive black hole is created, the gravitational effects are so huge that near by galaxies would feel it.. with it consuming so much mass, wouldn't gravity become so strong it would space/time itself into it?

Is that a possibility?

 

[Dicer]

I know that black holes are not big enough to pull everything in now but even now as we watch two black holes are fighting to eat one another to become even greater in size. Would it not mean that black holes will grow indefinitely as long as they have materials to consume? Thus growing so big and massive that they can then pull in space dust and even other galaxies from greater distances. Or could it be that a singular black hole will never eat up the entire universe but instead all the black holes throughout the universe will eat up their portion of the universe and eventually turning everything back into the plasma soup the the universe started as and then starting it all over with a big bang? Either way my original thought is still that black holes are what bring the universe back to its original form and eventually set it up for another big bang.

 

[MeteorWayne]

Again, black holes only "eat" material that comes close enough. Otherwise it just acts like a single mass. Even in Galaxies with a supermassive black hole at the center, the galaxy surrounding it has many times the mass of the black hole itself. All the other stars in the galaxy are in orbit around the center of mass of the entire galaxy, black hole and all. Almost none will ever come close enough to the black hole to be consumed. There are few quasars in the Universe relative to the number of galaxies; that shows how rare an event it is for a black hole to absorb much mass at all.

 

[Saiph]

Part of the answer lies in how the universe will end, via expansion, or contraction. If the universe continues to expand, what will be left will be clusters of black holes, and cold dead stellar cinders, with inert lumps of rock (dead planets) roaming about. Given the chaotic nature of multi-body systems, this may shrink over time, but that's what your left with, because these are the final, stable end products of stellar (and planetary) evolution.

If in contracts...well, you'll get the giant cosmic black hole only because you can't BE anywhere else, but this is far different from normal BH's that I wouldn't call it a single BH swallowing everything. This was the main idea for a cyclical universe, before modern observations have sent the field leaning towards my first example.

But a key underlying concept, which cannot be stressed enough, is that BH's from a reasonable distance (say an AU away or so) are absolutely no different than any other body of equivalent mass. If you have two galaxy sized BH's...then they'll treat eachother, and other objects, as if they were two galaxies (gravitationally)

 

[Dicer]

Again, black holes only "eat" material that comes close enough. Otherwise it just acts like a single mass. Even in Galaxies with a supermassive black hole at the center, the galaxy surrounding it has many times the mass of the black hole itself. All the other stars in the galaxy are in orbit around the center of mass of the entire galaxy, black hole and all. Almost none will ever come close enough to the black hole to be consumed. There are few quasars in the Universe relative to the number of galaxies; that shows how rare an event it is for a black hole to absorb much mass at all.

But is it not black holes that make galaxies bring in all things toward its center into its event horizon:?: and because of this eating all that it can?

 

[Dicer]

Part of the answer lies in how the universe will end, via expansion, or contraction. If the universe continues to expand, what will be left will be clusters of black holes, and cold dead stellar cinders, with inert lumps of rock (dead planets) roaming about. Given the chaotic nature of multi-body systems, this may shrink over time, but that's what your left with, because these are the final, stable end products of stellar (and planetary) evolution.

If in contracts...well, you'll get the giant cosmic black hole only because you can't BE anywhere else, but this is far different from normal BH's that I wouldn't call it a single BH swallowing everything. This was the main idea for a cyclical universe, before modern observations have sent the field leaning towards my first example.

But a key underlying concept, which cannot be stressed enough, is that BH's from a reasonable distance (say an AU away or so) are absolutely no different than any other body of equivalent mass. If you have two galaxy sized BH's...then they'll treat eachother, and other objects, as if they were two galaxies (gravitationally)

But is that not going under the assumption that all black holes are the same size and have the same gravitational pull?

 

[MeteorWayne]

But is it not black holes that make galaxies bring in all things toward its center into its event horizon:?: and because of this eating all that it can?

No. black holes do not "bring everything in to the center". Everything in the galaxy (even the black hole itself) orbits around the center of mass of the galaxy, of which the black hole is only a small part. The same as in the solar system, everything, including the sun orbits around the center of mass of the solar system.
In fact in the solar system, the sun is more than 99% of the mass, but it still orbits abound the center of mass of the whole system.

 

[MeteorWayne]

But is that not going under the assumption that all black holes are the same size and have the same gravitational pull?

It doesn't make any difference how big and or massive the black hole is. It just is a certain amount of mass, either large or small. The only difference is that in the black hole all that mass is concentrated in a very small area. But unless you are very close, that makes no difference.

Say you have a 10 million solar mass cluster at the center of a galaxy made of millions of stars. And say you have a 10 million solar mass black hole, the size of the solar system. Once you are light year away (much closer than the nearest star is to us), It makes no difference if it's a black hole or a cluster of stars. It's still just a certain amount of mass, with a certain amount of gravity.

 

[DrRocket]

But is that not going under the assumption that all black holes are the same size and have the same gravitational pull?

Black holes are NOT all the same size and have the same gravitational pull.

All that a black hole is is a bit of space-time which is so highly curved that light (hence nothing else) can escape from it. That is due to very high mass density, not high mass. In theory black holes can be quite small (sub-atomic).

Associated with a black hole is a sphere called the event horizon The event horizon is that surface at which the escape velocity, calculated according to ordinary Newtonian gravitational theory equals the speed of light. What it inside the event horizon stays inside the event horizon. Outside of the event horizon an observer sees ordinary gravity as though the source is a mass equal to the mass of the black hole located at the center of the black hole. So a black hole, outside of the event horizon, has normal gravitational attraction as would normally be associated with whatever mass has gone into the hole. Nothing more and nothing less.

There is a phenomena associated with black holes, a quantum phenomena discovered and predicted by Stephen Hawking, that is of some interest. It is called Hawking radiation. Basically virtual particle pairs near the event horizon can contribute one-half of the pair to the blackhole, while the second half moves away from the horizon. The net result is a loss of mass to the black hole. Eventually the black hole can evaporate. This is a VERY slow process for large black holes, but would be very quick for sub-atomic black holes.

If you would like to read a good exposition for a general audience, Kip Thorne's book Black Holes and Time Warps, Einstein's Outrageous Legacy is highly recommended. If you want a presentation in terms of real physics you might try Gravitation by Misner, Thorne and Wheeler or Chandrasekhar's The Mathematical Theory of Black Holes.

 

[Dicer]

But is that not going under the assumption that all black holes are the same size and have the same gravitational pull?

It doesn't make any difference how big and or massive the black hole is. It just is a certain amount of mass, either large or small. The only difference is that in the black hole all that mass is concentrated in a very small area. But unless you are very close, that makes no difference.

Say you have a 10 million solar mass cluster at the center of a galaxy made of millions of stars. And say you have a 10 million solar mass black hole, the size of the solar system. Once you are light year away (much closer than the nearest star is to us), It makes no difference if it's a black hole or a cluster of stars. It's still just a certain amount of mass, with a certain amount of gravity.

AWwwww i did not think this through enough aparently thank you all for you info

 

[Saiph]

No problem Dicer. Just glad to be able to help the curious

BTW, I took care of your double post.

 

[Boris_Badenov]

Big Crunch
From Wikipedia, the free encyclopedia

In physical cosmology, the Big Crunch is one possible scenario for the ultimate fate of the universe, in which the metric expansion of space eventually reverses and the universe recollapses, ultimately ending as a black hole singularity.

http://en.wikipedia.org/wiki/Big_Crunch

 

[Dicer]

Big Crunch
From Wikipedia, the free encyclopedia

In physical cosmology, the Big Crunch is one possible scenario for the ultimate fate of the universe, in which the metric expansion of space eventually reverses and the universe recollapses, ultimately ending as a black hole singularity.

http://en.wikipedia.org/wiki/Big_Crunch

You know wikipedia is not the best source for info but ill check out some other sites for that

 

[Dicer]

No problem Dicer. Just glad to be able to help the curious

BTW, I took care of your double post.

thanks i was trying to fix my spelling and did the double post lol

 

[Saiph]

I agree that wikipedia isn't the best source, but like the ink and paper tomes of the ole' days it is a good place to start. It'll give you a reasonably accurate overview on most subjects, and the nomenclature with which to continue a more thorough search for the information you want.

 

[MeteorWayne]

Alos wikipedia usually provides references at the bottom of the article which lead to the orignal sources.