The End of the Universe: A Black Hole Solution?

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The discussion explores the potential fate of the universe, particularly regarding black holes and their role in consuming ordinary matter. It raises the question of whether all matter will eventually end up in black holes, with references to Sean M. Carroll's views on the topic. Participants debate the nature of dark matter and dark energy, suggesting they may not be actual forms of matter but placeholders for unknown phenomena. The conversation also touches on the long timescales involved in cosmic evolution and the implications of black holes on galactic structures. Ultimately, the fate of the universe remains uncertain, with various theories and speculations presented.
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If we proposed that the universe is expanding forever, will black holes eventually get rid of all ordinary matter? and what remains of the universe is just dark matter and dark energy ?
 
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If there is a black hole in the center of a galaxy, then it will probably suck the galaxy into it eventually, but I don't know if every galaxy has to have black hole in its center, or if it's not possible for a body to have stable orbit around such black hole.

Dark matter and dark energy are not necessarily actual matter and energy. These are just placeholder names for phenomena that we don't yet understand that look *like* it were matter and energy at work, that we can't see. It could turn out that it's not an additional matter, but that our equations were wrong, or that we were looking in wrong place/wrong way.
 
There are multiple ideas as to the ultimate fate of the universe such as the heat death.
jadeturners said:
I am not looking forward to witnessing the end of the universe. It's just so horrible.
Considering the time scales involved are on the order of 10100 years (ten thousand, trillion, trillion trillion, trillion, trillion, trillion, trillion, trillion times greater than the current age of the universe) I doubt anyone will be around to see it.
 
Cantstandit said:
If there is a black hole in the center of a galaxy, then it will probably suck the galaxy into it eventually, but I don't know if every galaxy has to have black hole in its center, or if it's not possible for a body to have stable orbit around such black hole.

Dark matter and dark energy are not necessarily actual matter and energy. These are just placeholder names for phenomena that we don't yet understand that look *like* it were matter and energy at work, that we can't see. It could turn out that it's not an additional matter, but that our equations were wrong, or that we were looking in wrong place/wrong way.

Sean M Carroll stated (in a talk on cosmology) that all matter would end up in black holes. I had previously ventured this opinion on these boards and was told 'no, that won't happen'. I currently have no idea who's right. This seems like a good thread to hammer it out.
 
salvestrom said:
Sean M Carroll stated (in a talk on cosmology) that all matter would end up in black holes. I had previously ventured this opinion on these boards and was told 'no, that won't happen'. I currently have no idea who's right. This seems like a good thread to hammer it out.
Why would you think it would? Note that black holes do not "suck". The gravity of a black hole is no different to the gravity of anything else, if the sun suddenly became a black hole it would make absolutely no difference to Earth's orbit (though it would get quite cold). To say that all matter will end up in black holes is to imply that over deep time all matter will at some point come into contact with a black hole. Without clear maths showing the probability of that it is an unfounded assertion especially considering the vanishingly small volume of the universe occupied by black holes.

See this section of the link I provided above.
 
Ryan_m_b said:
Why would you think it would? Note that black holes do not "suck". The gravity of a black hole is no different to the gravity of anything else, if the sun suddenly became a black hole it would make absolutely no difference to Earth's orbit (though it would get quite cold). To say that all matter will end up in black holes is to imply that over deep time all matter will at some point come into contact with a black hole. Without clear maths showing the probability of that it is an unfounded assertion especially considering the vanishingly small volume of the universe occupied by black holes.

See this section of the link I provided above.

Why I would think so isn't relevant. I was already shot down. The actual question is why did Sean M Carroll say it would.

EDiT: I actually read that link. It says 1-10% of a galaxy's content will end up in the black hole. The rest will be flung out into empty space and decay into photons.
 
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There is a black hole era, where most matter in galaxies will be concentrated (the rest will have decayed into photons and/or be ejected)

See

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

But eventually they too will decay away via Hawking radiation.

What happens after that point is a real puzzle. The approximations used in statistical mechanics start to break down when you deal with length and timescales of that magnitude, and all sorts of exotic effects start to become possible!
 
Wouldn't orbital energy be radiated away over huge timescales by gravity waves?
 
There are several effects at play. Stellar winds, accretion rate's of matter etc. But over long timescales black holes mostly grow until the CMB cools sufficiently at which point Hawking radiation will dominate.
 
  • #10
Haelfix said:
There is a black hole era, where most matter in galaxies will be concentrated (the rest will have decayed into photons and/or be ejected)

See

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

But eventually they too will decay away via Hawking radiation.

What happens after that point is a real puzzle. The approximations used in statistical mechanics start to break down when you deal with length and timescales of that magnitude, and all sorts of exotic effects start to become possible!
As I see it electrical charges are stripped out of their atoms and ejected from black holes as high energy cosmic rays. The ultimate fate of the universe is charged particles and radiation. I suspect gravitational fields separate oppositely charged particles until the electrostatic forces overcome gravitational forces. Charged particles come together and annihilate, causing the quark-gluon plasma to be formed and another big bang.
 
  • #11
While most mass may eventually reside in black holes, it is unlikely all of it has this destiny. Even an extraordinarily thin gruel of matter dispersed throughout space creates havoc with most bounce models - unless you are willing to settle for gazillion of years between bounces.
 
  • #12
ynot1 said:
As I see it electrical charges are stripped out of their atoms and ejected from black holes as high energy cosmic rays. The ultimate fate of the universe is charged particles and radiation. I suspect gravitational fields separate oppositely charged particles until the electrostatic forces overcome gravitational forces. Charged particles come together and annihilate, causing the quark-gluon plasma to be formed and another big bang.

I'm sorry, none of this makes any sense.
 
  • #13
ynot1 said:
As I see it electrical charges are stripped out of their atoms and ejected from black holes as high energy cosmic rays. The ultimate fate of the universe is charged particles and radiation. I suspect gravitational fields separate oppositely charged particles until the electrostatic forces overcome gravitational forces. Charged particles come together and annihilate, causing the quark-gluon plasma to be formed and another big bang.

"As I see it" and "I suspect" are not helpful arguments and your statements are utter nonsense. Read some physics.
 
  • #14
phinds said:
"As I see it" and "I suspect" are not helpful arguments and your statements are utter nonsense. Read some physics.
I'm not a lawyer. I'm not here to litigate. I'm here to propose what I view as a most plausible scenario. You might try reading up on Van de Graf generators. Imagine an outer shell of positrons and an inner shell of electrons. Do you understand electrostatic attraction between unlike charges? What would happen in that case?
 
  • #15
phinds said:
Now THERE'S something you and I can agree on (although not the "we" part). You are dealing not just in speculation but in unsubstantiated speculation that is absurd. A Van deGraff generator as a model of a black hole? REALLY?

Look, I'm coming across as rude in this and that's not actually my intent. It's just that I see your proposals as having no relation to actual physics except that you have mashed up some buzz words that are used in physics.

I mean take the thought

"gravitational fields separate oppositely charged particles"


I was not aware that charge has any effect on gravitational attraction. Do you have any references for this?
The Van de Graff generator is used as an analogy of the universe after the black holes have long gone. Sorry for the confusion.

Certainly charge has no affect on gravitational attraction. Only matter. Charged particles do have mass, I believe. And gravity has effect on mass. I'm suggesting gravity has an attractive force on matter and a repulsive force on antimatter. Positrons, being I believe antimatter, would then be repelled by gravity. Electrons, of course, attracted. So as long as gravity is around it will separate positrons and electrons. I know it's is a bit indirect. Difficult to understand I guess. But I wouldn't waste time looking for any references about charge having any effect on gravitational attraction. Could be though. I just never thought about it I guess.
 
  • #16
Ryan_m_b said:
Why would you think it would? Note that black holes do not "suck". The gravity of a black hole is no different to the gravity of anything else, if the sun suddenly became a black hole it would make absolutely no difference to Earth's orbit (though it would get quite cold). To say that all matter will end up in black holes is to imply that over deep time all matter will at some point come into contact with a black hole. Without clear maths showing the probability of that it is an unfounded assertion especially considering the vanishingly small volume of the universe occupied by black holes.

See this section of the link I provided above.
I understand even the proton decays, but before that time it would most likely be recycled by a black hole.
 
  • #17
ynot1 said:
Certainly charge has no affect on gravitational attraction. Only matter. Charged particles do have mass, I believe. And gravity has effect on mass. I'm suggesting gravity has an attractive force on matter and a repulsive force on antimatter. Positrons, being I believe antimatter, would then be repelled by gravity. Electrons, of course, attracted. So as long as gravity is around it will separate positrons and electrons. I know it's is a bit indirect. Difficult to understand I guess. But I wouldn't waste time looking for any references about charge having any effect on gravitational attraction. Could be though. I just never thought about it I guess.

The current view of science is that both matter and antimatter follow the same laws regarding gravity. It is "possible" that antimatter would be repelled, but by possible I mean that we simply haven't tested it conclusively yet.
 
  • #18
ynot1 said:
I understand even the proton decays, but before that time it would most likely be recycled by a black hole.

WHY? Where do you get this nonsense?
 
  • #19
phinds said:
He does, but I think the consensus is that that is just a math thing that gives good answers but stuff doesn't REALLY travel backwards in time. I not positive about that.
Perhaps an interesting observation about this speculation, consistent with Einstein's idea about time being treated on an equal footing with spatial dimensions would be that particles coexist moving in opposite directions in space. So they should coexist moving in opposite directions in time. But note since time is only one dimension particles can coexist for extended periods only if moving in opposite directions beginning with their creation. Otherwise they would collide and annihilate, similar to annihilation when they meet in space. Actually as I remember there are instances of time reversibility in Feynman diagrams but I think it only lasts for a fleeting moment until another collision. I doubt if you could get any bonus points in your relativity class for mentioning this observation. You might even get laughed at. So please don't tell them where you heard this idea.
 
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  • #20
phinds said:
WHY? Where do you get this nonsense?

A number of GUTS, as well as the disproved Steady State, call for proton decay. Experiments, such as the various water tanks in deep underground mines, have never seen proton decay, and have placed the lower limit on the half life of the proton at 1.01×10^34 years. That's 24 orders of magnitude greater than the current age of the universe.
 
  • #21
phinds said:
WHY? Where do you get this nonsense?
You're right. Probably. So do they get recycled by black holes? My guess is they may be ejected in cosmic rays. More nonsense?
 
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  • #22
ynot1 said:
You're right. Probably. So do they get recycled by black holes? My guess is their charge is stripped off on entry to the event horizon and their charges are ejected in cosmic rays. More nonsense?

Yep.
 
  • #23
Drakkith said:
The current view of science is that both matter and antimatter follow the same laws regarding gravity. It is "possible" that antimatter would be repelled, but by possible I mean that we simply haven't tested it conclusively yet.
Note matter attracts matter and I should think antimatter attracts antimatter. Also like charges repel. Therefore clouds of charged particles exist in a stable configuration, if such is possible, only if the gravitational attraction is balanced by electrostatic repulsion. If this isn't possible then my idea about clouds of electrons and positrons sinks. However if it is possible then the stable configurations would allow spacetime to shed its entropy. More nonsense I guess.
 
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  • #24
Antimatter has been created and stored for as long as 16 minutes.

If antimatter possesed reverse gravity, it would have been noted already.
 
  • #25
ynot1 said:
As I see it electrical charges are stripped out of their atoms and ejected from black holes as high energy cosmic rays. The ultimate fate of the universe is charged particles and radiation. I suspect gravitational fields separate oppositely charged particles until the electrostatic forces overcome gravitational forces. Charged particles come together and annihilate, causing the quark-gluon plasma to be formed and another big bang.

Gravity is an attractive force...
 
  • #26
ibysaiyan said:
Gravity is an attractive force...
The point of debate is for antimatter.
 
  • #27
alexg said:
Antimatter has been created and stored for as long as 16 minutes.

If antimatter possesed reverse gravity, it would have been noted already.
I believe it has been noted already. If antimatter didn't possesses reverse gravity (or positive gravity, for that matter) on the surface of the Earth they wouldn't have to use magnetic confinement. In orbit, now that would be an interesting experiment.
 
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  • #28
ynot1 said:
I believe it has been noted already. If antimatter didn't possesses reverse gravity on the surface of the Earth they wouldn't have to use magnetic confinement. In orbit, now that would be an interesting experiment.
Magnetic confinement in orbit might be a good idea though. Just in case.
 
  • #29
ynot1 said:
Note matter attracts matter and I should think antimatter attracts antimatter. Also like charges repel. Therefore clouds of charged particles exist in a stable configuration, if such is possible, only if the gravitational attraction is balanced by electrostatic repulsion. If this isn't possible then my idea about clouds of electrons and positrons sinks. However if it is possible then the stable configurations would allow spacetime to shed its entropy. More nonsense I guess.
I don't think like charges will ever be attracted by gravity and so this idea sinks. However it suggests a possible mechanism for CP violation in pair production - the gravitational field.
 
  • #30
ynot1 said:
I don't think like charges will ever be attracted by gravity and so this idea sinks. However it suggests a possible mechanism for CP violation in pair production - the gravitational field.
However note protons do attract protons at subatomic distances per
 
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  • #31
alexg said:
A number of GUTS, as well as the disproved Steady State, call for proton decay. Experiments, such as the various water tanks in deep underground mines, have never seen proton decay, and have placed the lower limit on the half life of the proton at 1.01×10^34 years. That's 24 orders of magnitude greater than the current age of the universe.

I was not talking about proton decay. I was talking about

it would most likely be recycled by a black hole

I cannot see any foundation for such a statement.
 
  • #32
phinds said:
I was not talking about proton decay. I was talking about

"it would most likely be recycled by a black hole"

I cannot see any foundation for such a statement.
Very interesting. Ergo black holes do not recycle protons (back into radiation). So protons will be part of the end game along with the leptons.
 
  • #33
ynot1 said:
I believe it has been noted already. If antimatter didn't possesses reverse gravity (or positive gravity, for that matter) on the surface of the Earth they wouldn't have to use magnetic confinement. In orbit, now that would be an interesting experiment.

Magnetic confinement is used, not to prevent the antimatter for falling upward, but to keep it from contact with normal matter.

Antimatter does not have reverse gravity.
 
  • #34
ynot1 said:
Very interesting. Ergo black holes do not recycle protons (back into radiation). So protons will be part of the end game along with the leptons.

No, my point is not that black holes would not recycle them ... I'm not even commenting on that. My point is that they aren't going to fall into black holes in the first place.

Why do you think everything will go into a black hole at some point?
 
  • #35
phinds said:
No, my point is not that black holes would not recycle them ... I'm not even commenting on that. My point is that they aren't going to fall into black holes in the first place.

Why do you think everything will go into a black hole at some point?
Are you serious? Here is the second sentence of the post you are referencing: "So protons will be part of the end game along with the leptons." To me that leaves protons and the leptons not falling into black holes.
 
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  • #36
alexg said:
Magnetic confinement is used, not to prevent the antimatter for falling upward, but to keep it from contact with normal matter.

Antimatter does not have reverse gravity.
Except in the southern part of the inner Van Allen belt where it's also trapped by magnetic confinement. Seems strange.
 
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  • #37
ynot1 said:
Except in the southern part of the inner Van Allen belt where it's also trapped by magnetic confinement. Seems strange.

What are you talking about? There is no antimatter held in the Van Allen belt. Where do you come up with this?
 
  • #38
alexg said:
What are you talking about? There is no antimatter held in the Van Allen belt. Where do you come up with this?
Really? Check out http://www.physicstoday.org/resource/1/phtoad/v64/i10/p16_s1?isAuthorized=no&view=print
 
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  • #39
ynot1 said:
Are you serious? Here is the second sentence of the post you are referencing: "So protons will be part of the end game along with the leptons." To me that leaves protons and the leptons not falling into black holes.
That is interesting. It means when stars collapse to form black holes they lose about 50% of their mass from their protons which don't fall into the black hole.
 
  • #40
ynot1 said:
Note matter attracts matter and I should think antimatter attracts antimatter. Also like charges repel. Therefore clouds of charged particles exist in a stable configuration, if such is possible, only if the gravitational attraction is balanced by electrostatic repulsion. If this isn't possible then my idea about clouds of electrons and positrons sinks. However if it is possible then the stable configurations would allow spacetime to shed its entropy. More nonsense I guess.

Again, the current view of physics is that both matter and antimatter are attracted by gravity. Anything is mostly speculation at this point and should be avoided unless you are talking about a specific model, which you are not. Furthermore, please stop posting about your "ideas", as they don't make any sense usually and could be considered to be against PF rules.

ynot1 said:
I believe it has been noted already. If antimatter didn't possesses reverse gravity (or positive gravity, for that matter) on the surface of the Earth they wouldn't have to use magnetic confinement. In orbit, now that would be an interesting experiment.

As has been pointed out they use magnetic confinement because if they didn't the particles would impact the walls of the containment vessel and annihilate with normal matter.

ynot1 said:
I don't think like charges will ever be attracted by gravity and so this idea sinks. However it suggests a possible mechanism for CP violation in pair production - the gravitational field.

I have no idea what you are talking about. Gravity has nothing to do with charge according to standard science.

ynot1 said:
However note protons do attract protons at subatomic distances per


Protons attract because of the strong force, not because of anything else. Please stop posting links to this guy. At minimum it doesn't meet the requirements for being the "standard model" and shouldn't be discussed here.

ynot1 said:
That is interesting. It means when stars collapse to form black holes they lose about 50% of their mass from their protons which don't fall into the black hole.

A large part of the mass of a star is blown outwards in the supernova process. Are you referring to this process or something intrinsic to the black hole formation? And why do you keep quoting yourself? It's very confusing.

ynot1 said:
Except in the southern part of the inner Van Allen belt where it's also trapped by magnetic confinement. Seems strange.

Why would this be strange? Antimatter is charged and obeys the same electromagnetic laws that normal matter does. It is far from strange.
 
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  • #41
Drakkith said:
Why would this be strange? Antimatter is charged and obeys the same electromagnetic laws that normal matter does. It is far from strange.
Yes except antimatter travels in reverse time. So its electrical and gravitational charge (actually curvature in spacetime) are reversed. Same electromagnetic laws, same gravitational laws, only in reverse time. Note opposite charges curve in opposite directions in an electromagnetic field. I assume matter and antimatter do the same in a gravitational field. It's a matter of symmetry, actually. Sorry about all those obscure posts. I'll try to make them more understandable. Thanks.
 
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  • #42
ynot1 said:
Yes except antimatter travels in reverse time. So its electrical and gravitational charge (actually curvature in spacetime) are reversed. Same electromagnetic laws, same gravitational laws, only in reverse time. Sorry about all those obscure posts. I'll try to make them more understandable. Thanks.

No, the standard view is that it does NOT travel backwards in time. Please, try to learn the standard view of physics before jumping into things that are "beyond" the standard model. Just because one physicist says that the math shows it might travel backwards in time does not mean it is true.
 
  • #43
the transition of the universe from the degenerate era to the black hole era and finally to the dark era depends upon whether or not proton decay occurs. If it occurs, it will be relatively soon, if it doesn't occur, it will be much much longer.

http://en.wikipedia.org/wiki/Timeline_of_the_far_future
 
  • #44
Drakkith said:
No, the standard view is that it does NOT travel backwards in time. Please, try to learn the standard view of physics before jumping into things that are "beyond" the standard model. Just because one physicist says that the math shows it might travel backwards in time does not mean it is true.
Sorry about the standard model. I'd really prefer to go with Einstein, Feynman, and Dirac, if you don't mind.
 
  • #45
Dremmer said:
the transition of the universe from the degenerate era to the black hole era and finally to the dark era depends upon whether or not proton decay occurs. If it occurs, it will be relatively soon, if it doesn't occur, it will be much much longer.

http://en.wikipedia.org/wiki/Timeline_of_the_far_future
Per your reference,

"All predictions of the future of the Earth, the Solar System and the Universe must account for the second law of thermodynamics, which states that entropy, or a loss of the energy available to do work, must increase over time.[1]"

True for time moving in the forward direction. It seems the opposite would hold for time moving backwards. The universe, being symmetrical, has to do both simultaneously. There is not an arrow of time, there are arrows of time, pointing inwards or outwards depending on your reference. Apologies to you standard model devotees. Call it heresy, or at least non-standard, if you wish.
 
  • #46
But, there are no observational examples where time appears to be moving backwards, which places your postulate in the realm of unsupported speculation.
 
  • #47
Chronos said:
But, there are no observational examples where time appears to be moving backwards, which places your postulate in the realm of unsupported speculation.
I believe instances of time reversal are quite common in particle physics as used in Feynman diagrams.
 
  • #48
Chronos said:
But, there are no observational examples where time appears to be moving backwards, which places your postulate in the realm of unsupported speculation.
On macroscopic scales such time reversals are possible but very improbable per Feynman. Feynman goes on to explain how a mechanical ticking clock can run backwards. He says there's no physical laws to prevent this, and explains exactly how it could happen. The laws of probability (for example, thermodynamics) are not laws of physics. Note however that Feynman explains time reversibility using causality (how you would explain anything with anti-causality mystifies me). Ergo the arrows of time or causality point in both directions. Antimatter is just as much subject to causality as matter.
 
  • #49
Er, so do you have an actual observation to cite as opposed to theoretical possibilites?
 
  • #50
Chronos said:
Er, so do you have an actual observation to cite as opposed to theoretical possibilites?
Yes I think I mentioned something about that with the Feynman diagrams.
 

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