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Is this a new thought? Seems like natural thinking to me... Not an expert so would love someone more knowledgeable to chime in.

walru 12y ago
It does seem like natural thought - that at some point even a black hole reaches it's maximum density. However, I do seem to recall (some) black holes shoot a stream of particles from either pole (eg. an Astrophysical Jet (http://en.wikipedia.org/wiki/Astrophysical_jet http://en.wikipedia.org/wiki/Astrophysical_jet). In that case, it's plausible that it doesn't take on additional mass and thus never reaches a maximum stress point, thus doesn't explode. Of course there's another theory that they're dumping that matter elsewhere.. but who knows. I imagine much of what we currently believe will be disproved in the decades and centuries to come.
- privong 12y ago
  > In that case, it's plausible that it doesn't take on additional mass and thus never reaches a maximum stress point, thus doesn't explode. In the current understanding of jets from black holes, the jets originate from outside the black hole. So the jets are not reducing the mass of the black hole. The amount of material launched in a jet is smaller than the amount of material which falls into the black hole. So black holes with jets would gain mass, rather than losing mass or staying the same mass.
- pingou 12y ago
  Is it a natural thought? I'm not an expert but I thought it would just bigger and bigger. For the dumping matter part, they talk in the article of the hawking radiation, I think the astrophysical jet wouldn't reduce the mass of a black hole but only slow its rotation, as the matter haven't reached the event horizon it would not be considered part of it. Again, I'm no expert, so you shouldn't trust me.
- Udo 12y ago
  > It does seem like natural thought - that at some point even a black hole reaches it's maximum density. There is no compelling reason, neither theoretical nor observational, that black holes should have a maximum mass. In fact, we've observed some extraordinarily heavy black holes and so far no upper bound has become visible other than factors stemming from the amount of time active and the environment in their vicinity that allowed those holes to grow. > However, I do seem to recall (some) black holes shoot a stream of particles from either pole That happens whenever a lot of matter accretes around a source of gravity - a hot disk is formed and matter is accelerated out of the poles. It happens with heavy objects other than black holes as well. The ejected matter comes from the accreted stuff, not from the black hole itself. > In that case, it's plausible that it doesn't take on additional mass and thus never reaches a maximum stress point, thus doesn't explode No, only a small part of the accreted matter is ejected. > Of course there's another theory that they're dumping that matter elsewhere.. There is no plausible theory at this point that suggests anything of that nature. Matter as we know it ceases to exist in a black hole, it becomes compressed in a way that its usual properties are lost - so much so that in fact, how and if information loss happens in a black hole is still a matter of debate and has led to some credible theories on how information and entropy might be preserved at the border to ordinary space. There is also nothing to suggest that black holes are losing mass at any appreciable rate, other than possibly through Hawking radiation. Combined with the fact that the known cosmos does not exhibit any regions where measurable amounts of matter simply come into existence, the idea that opposite of every black hole is a white hole spewing out the stuff both ignores the fact that black holes get bigger by ingestion and the lack of any evidence for matter spewers. Of course that does not prove it's not happening, but there is zero reason at the moment to believe this is going on. And that pertains to this article as well, the content being presented here is not supported by any evidence or current theoretical modeling.
  - Tyrant505 12y ago
    So will the universe eventually just have black holes?
    - Udo 12y ago
      Not strictly speaking. Black holes are just ordinary gravity wells. They're strong, and stuff falls into them, but they don't actively suck stuff in anymore than planets or stars do. However, over very long time spans, orbiting systems should lose energy by radiating gravitational waves. That means after an inordinately long period of time, and after ejecting a lot of its mass, each galaxy will likely end up just one big black hole. But there is always stuff traveling through the universe that is not gravitationally bound to anything, and since space itself is expanding, a lot of the matter in the universe will just keep on drifting without ever colliding with anything ever again. Not that it matters from a practical perspective. Once the last stars have gone cold, that's pretty much as good a definition of "the end" as any other, and that will happen long before maximum entropy is reached. There might not be a definite end state to the universe itself, but there are certainly some thresholds past which everything will become so boring that we may just as well consider them to be final.
thret 12y ago
TL;DR? This was covered on the show Red Dwarf. https://www.youtube.com/watch?v=TxWN8AhNER0 https://www.youtube.com/watch?v=TxWN8AhNER0 Natural question: was the big bang a white hole?
- bellerocky 12y ago
  > Natural question: was the big bang a white hole? The big bang theory describes the early moments in the Universe's expansion of space, not the projection of matter from a single point in space.
  - ck2 12y ago
    White hole could maybe also create its own universe with that matter projecting into it. The sheer volume and energy/speed perhaps.
    - bellerocky 12y ago
      I don't have any idea, but to me it sounds like you're just making things up now.

walru 12y ago

It does seem like natural thought - that at some point even a black hole reaches it's maximum density. However, I do seem to recall (some) black holes shoot a stream of particles from either pole (eg. an Astrophysical Jet (http://en.wikipedia.org/wiki/Astrophysical_jet http://en.wikipedia.org/wiki/Astrophysical_jet). In that case, it's plausible that it doesn't take on additional mass and thus never reaches a maximum stress point, thus doesn't explode. Of course there's another theory that they're dumping that matter elsewhere.. but who knows. I imagine much of what we currently believe will be disproved in the decades and centuries to come.

privong 12y ago
> In that case, it's plausible that it doesn't take on additional mass and thus never reaches a maximum stress point, thus doesn't explode. In the current understanding of jets from black holes, the jets originate from outside the black hole. So the jets are not reducing the mass of the black hole. The amount of material launched in a jet is smaller than the amount of material which falls into the black hole. So black holes with jets would gain mass, rather than losing mass or staying the same mass.
pingou 12y ago
Is it a natural thought? I'm not an expert but I thought it would just bigger and bigger. For the dumping matter part, they talk in the article of the hawking radiation, I think the astrophysical jet wouldn't reduce the mass of a black hole but only slow its rotation, as the matter haven't reached the event horizon it would not be considered part of it. Again, I'm no expert, so you shouldn't trust me.
Udo 12y ago
> It does seem like natural thought - that at some point even a black hole reaches it's maximum density. There is no compelling reason, neither theoretical nor observational, that black holes should have a maximum mass. In fact, we've observed some extraordinarily heavy black holes and so far no upper bound has become visible other than factors stemming from the amount of time active and the environment in their vicinity that allowed those holes to grow. > However, I do seem to recall (some) black holes shoot a stream of particles from either pole That happens whenever a lot of matter accretes around a source of gravity - a hot disk is formed and matter is accelerated out of the poles. It happens with heavy objects other than black holes as well. The ejected matter comes from the accreted stuff, not from the black hole itself. > In that case, it's plausible that it doesn't take on additional mass and thus never reaches a maximum stress point, thus doesn't explode No, only a small part of the accreted matter is ejected. > Of course there's another theory that they're dumping that matter elsewhere.. There is no plausible theory at this point that suggests anything of that nature. Matter as we know it ceases to exist in a black hole, it becomes compressed in a way that its usual properties are lost - so much so that in fact, how and if information loss happens in a black hole is still a matter of debate and has led to some credible theories on how information and entropy might be preserved at the border to ordinary space. There is also nothing to suggest that black holes are losing mass at any appreciable rate, other than possibly through Hawking radiation. Combined with the fact that the known cosmos does not exhibit any regions where measurable amounts of matter simply come into existence, the idea that opposite of every black hole is a white hole spewing out the stuff both ignores the fact that black holes get bigger by ingestion and the lack of any evidence for matter spewers. Of course that does not prove it's not happening, but there is zero reason at the moment to believe this is going on. And that pertains to this article as well, the content being presented here is not supported by any evidence or current theoretical modeling.
- Tyrant505 12y ago
  So will the universe eventually just have black holes?
  - Udo 12y ago
    Not strictly speaking. Black holes are just ordinary gravity wells. They're strong, and stuff falls into them, but they don't actively suck stuff in anymore than planets or stars do. However, over very long time spans, orbiting systems should lose energy by radiating gravitational waves. That means after an inordinately long period of time, and after ejecting a lot of its mass, each galaxy will likely end up just one big black hole. But there is always stuff traveling through the universe that is not gravitationally bound to anything, and since space itself is expanding, a lot of the matter in the universe will just keep on drifting without ever colliding with anything ever again. Not that it matters from a practical perspective. Once the last stars have gone cold, that's pretty much as good a definition of "the end" as any other, and that will happen long before maximum entropy is reached. There might not be a definite end state to the universe itself, but there are certainly some thresholds past which everything will become so boring that we may just as well consider them to be final.

thret 12y ago

TL;DR? This was covered on the show Red Dwarf. https://www.youtube.com/watch?v=TxWN8AhNER0 https://www.youtube.com/watch?v=TxWN8AhNER0 Natural question: was the big bang a white hole?

bellerocky 12y ago
> Natural question: was the big bang a white hole? The big bang theory describes the early moments in the Universe's expansion of space, not the projection of matter from a single point in space.
- ck2 12y ago
  White hole could maybe also create its own universe with that matter projecting into it. The sheer volume and energy/speed perhaps.
  - bellerocky 12y ago
    I don't have any idea, but to me it sounds like you're just making things up now.