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Energy, blackholes and whiteholes

  1. Jan 3, 2010 #1
    if a black hole absorbs mass and makes it dissapear from this universe. Where is the missing energy from that mass in the universe, considering that the total energy is a constant.
    Could it be white holes the answer?
  2. jcsd
  3. Jan 3, 2010 #2


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    It doesn't make mass disappear. When a BH absorbs something, it (the Black Hole) increases in mass...
  4. Jan 5, 2010 #3
    The same problem was asked in the time of einstein, what happens to the energy and mass of the black hole, then in other not the violate the conservation of energy, it was considered viable to introduce the whitehole concept. So the energy is not loast instead it is released in the other end of the whitehole so everything is balanced in the universe. this is the easiest explanation i can give you.
  5. Jan 6, 2010 #4
    White holes were really cooked up as a way to explain Quasars. At the time when some research was being done, the age of the universe (relating therefore to distance) was calculated to be less than it is now. The apparent "brightness" of the objects seemed impossible for any known body, and it was postulated (although never widely accepted) that these could White Holes, where the matter that was seemingly lost in a Black Hole was blasted back into the universe.

    I would hasten to correct one statement however; the notion that a black hole "absorbs mass and makes it disappear from this universe" is very much a topic of current debate. This is a central issue in theoretical physics called "The Information Paradox", popularly. For any Unitary system, which quantum physics currently is telling us we're in, information is never LOST. This has led to various ideas being floated, from the absurd to the likely.

    The leading candidates are that, yes, Black Holes are unique regions of spacetime and in that place matter is crushed out of existence, to be emitted as Hawking Radiation which would violate Unitarity. The other is that the information is "encoded" so to speak, in minute fluctuations of the event horizon of the black hole. Others have posited (as they do since Einstein's equations predicted Black Holes) that Black Holes don't exist. Instead there are arguments for the notion that a black hole is always JUST prevented from forming as the star collapses. This generally involves models of inhomogeneous gasses and their collapse, vs. expected vacuum pressure, etc, and are not widely accepted or even fully formulated.

    Finally, as always, there are those who believe that in defiance of many laws that would say otherwise, the information lost inside a black hole is only lost until it evaporates... leaving a super dense remnant. This... is frankly silly from my point of view based on my limited understanding of how much information can be encoded in a given region, but it seems unlikely. Thorne or Hawking... pick a side lol. Oh, as for how a black hole LOSES its mass, that is currently believed to be through a process called Hawking Radiation, but that is entirely theoretical as well and depends on a particular understanding of how particle anti-particle pairs/particles moving through time in the region of the black hole. Right now to be blunt, they are thought to evaporate in a thermodynamic process in accordance with GR, but not The Standard Model
  6. Jan 6, 2010 #5
    According to history specifically( the book blackholes) White holes appear as part of the vacuum solution to the Einstein field equations describing a Schwarzschild wormhole. One end of this type of wormhole is a black hole, drawing in matter, and the other is a white hole, emitting matter. But While this gives the impression that black holes in our universe may connect to white holes elsewhere, in reality, this is untrue, for two reasons. First, Schwarzschild wormholes are unstable, disconnecting as soon as they form. Second, Schwarzschild wormholes are only a solution to the Einstein field equations in vacuum (when no matter interacts with the hole). Real black holes are formed by the collapse of stars. So basically in reality Blackholes are very bad stuffs to mess with because they basically throw you off course. There hasnt been any real explanation of how balckholes work just speculations.A more recently proposed view of black holes might be interpreted as shedding some light on the nature of classical white holes. Some researchers proposed that when a black hole forms, a big bang occurs at the core, which creates a new universe that expands into extra dimensions outside of the parent universe. All pointing towards the same direction that mainstream science is still battling the concept of blackholes.
  7. Jan 21, 2010 #6
    what if there were 2 black holes end to end
  8. Jan 21, 2010 #7
    I know what you're trying to say, but even that is essentially meaningless. Two black holes "overlapping" in space-time would be... THE SAME BLACK HOLE. Scifi sometimes likes to take that idea and say that any two black holes can be made to "join" in some mystical way. There is no evidence of this, although there are solutions in theoretical models that allow for that kind of geometry, it seems not to exist in this universe at any point in its known history.

    Edit: Another answer I or anyone here could have given would be "They don't have ends", "That is a meaningless question/statement", and "What if pigs could fly, so what then?!". Just saying, your question reveals a fundamental ignorance. I don't mean that as an insult, but a spur to learn. BHs are fascinating, but they're not really the starting point for all physics.
  9. Jan 23, 2010 #8
    Woudn't that be a wormhole
  10. Jan 23, 2010 #9
  11. Feb 12, 2010 #10
    Have you ever heard of the reflection geometry? It is 2 black holes end 2 end. It is a swartzchild wormhole just with 2 black holes.
  12. Feb 12, 2010 #11
    Or what about a naked singularity. A singularity without a hole would not be deadly. It would probably create a wormhole. None have been discovered.
  13. Feb 12, 2010 #12
    Read my posts after yours online. At physicsforums.
  14. Feb 12, 2010 #13
    Pherhaps a whitehole is just a black hole of exotic negative matter. Maybe that is just anti matter gravitons.
  15. Feb 12, 2010 #14
    I don't know what's occured between the 23'rd of last month and today that made you feel the need to quadruple post within a five minute span. I am going to politely bow out of this, as I have to be blunt; your question has been answered and I am not the person to be 'polite' in these situations. Better a PF mentor handle this, if each question is to be fully answered.

    MY answer is that you've brought borderline/actual science-FICTION to the table now. I have no comment on purely wild theory. CAN you formulate an inhomogeneous star, accounting for gas pressures and imagine a naked singularity forming on paper? Yes. Does it hold universally for more massive bodies and is it STABLE?! NO. The appearence of observed objects believed to be BHs appear to act in line with expectations of a BH with an EH, and even those proponants of sub-EH collapse aren't talking about naked singularities.

    As for exotic negative matter... cite some of that please. Outside of quantum effects regarding POSSIBLE negative energy density (and maybe Komar Mass) I've only heard the term 'negative MATTER' in a purely scifi context. Always, this is used as a means of 'holding open' an Einstein-Rosen Bridge and violate causality.

    As for posts #10 and #12, they are eqaully unilluminating. Finally, anti matter gravitons?! ARE YOU HIGH? Did you not go back to the intial point that 'white holes' are NOT an accepted theory? White Holes were pure conjecture to explain a brief period of uncertainty regarding the nature of Quasars.

    If you want to believe in traversable wormholes, or you need ideas for writing scifi, I'm all for it! (the latter more than former)...

    That's not for THIS area however.
  16. Feb 13, 2010 #15
    You're just combining concepts randomly which really don't belong together.

    Firstly, a whitehole is a time-reversed black-hole and doesn't have anything to do with the exotic matter discussions of Kip Thorne & later theorists. 'Negative matter' isn't exotic matter - it's a speculative concept from Robert Forward, but presently doesn't have a lot of theoretical support. He uses to good fictional effect as a means of keeping Thorne-style wormholes open and as part of an unusual space-drive, but it doesn't really have a place in physics as we know it. Exotic matter has slightly more theoretical basis, but not much.

    Now as for "antimatter gravitons"... *sigh* It's hard to say what that even means. Two possibilities - antimatter baryons & leptons have gravitational mass just like regular matter so their gravitons are no different. But you might mean anti-gravitons - but gravitons are probably just like photons and their antiparticles are also gravitons, just like an 'anti-photon' is just a photon.
  17. Feb 13, 2010 #16
    You sir, should be considered for sainthood. At what point do we stop answering questions and just scream, "NUTS!!!!". Keep in mind I have one degree in clinical psychology, so I don't use the term 'nuts' lightly. He MISSED the Douglas Adams (Author) reference about the cake and RAN with the concept. :cry:
  18. Feb 13, 2010 #17
    Hey, me too! Though I never did Honours and specialised. My B.Sc was a Psych double major. Main thing I remembered was all the stuff on "Active Listening" that they did so well in Social/Organisational Psych. Psychopathology has never looked the same ever since I spent time socialising with victims of drug psychosis & schizophrenics.

    Sometimes the best insights come from parody & humour. But yes our interlocutor was excessively earnest and missed the lighter side.
  19. Feb 14, 2010 #18
    Well said on both counts! :)
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