Black holes may not exist!

Discussion in 'Physics & Math' started by RJBeery, Jan 24, 2014.

  1. przyk squishy Valued Senior Member

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    You are trying to get me to commit to something that has no justification in general relativity. It's not that you can't get me to commit to anything. You have the whole of the theoretical foundation of general relativity to argue based on, and for the purpose of this discussion you can assume I am committed to that.

    And contrary to what you say earlier:

    if you need to treat a particular coordinate system as "special", you are rejecting GR.
     
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  3. Farsight Valued Senior Member

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    Oh phooey. See Kevin Brown's formation and growth of black holes:

    http://mathpages.com/rr/s7-02/7-02.htm

    "Incidentally, I should probably qualify my dismissal of the "frozen star" interpretation, because there's a sense in which it's valid, or at least defensible. Remember that historically the two most common conceptual models for general relativity have been the "geometric interpretation" (as originally conceived by Einstein) and the "field interpretation" (patterned after the quantum field theories of the other fundamental interactions). These two views are operationally equivalent outside event horizons, but they tend to lead to different conceptions of the limit of gravitational collapse. According to the field interpretation, a clock runs increasingly slowly as it approaches the event horizon (due to the strength of the field), and the natural "limit" of this process is that the clock just asymptotically approaches "full stop" (i.e., running at a rate of zero) as it approaches the horizon. It continues to exist for the rest of time, but it's "frozen" due to the strength of the gravitational field. Within this conceptual framework there's nothing more to be said about the clock's existence. This leads to the "frozen star" conception of gravitational collapse. In contrast, according to the geometric interpretation..."

    This GR interpretation is in line with what RJBeery is saying. As to whether that means the event horizon doesn't exist is another issue. I have no issue with black holes existing whatever the fine details of event horizons etc. They're massive, they're small, they're black. Light goes in and it doesn't come out.
     
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  5. RJBeery Natural Philosopher Valued Senior Member

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    I don't see it that way; it's that the concept of today lies outside the realm of GR. This is a point that you've already said you agree with. If GR cannot define "today" or "now" then it simply cannot address the question of whether or not black holes exist today.
     
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  7. RJBeery Natural Philosopher Valued Senior Member

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    *like*

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  8. nimbus Registered Senior Member

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    ''stopping at it'' ?
    You are taking the stance that there are special frames that are to be treated as absolute in GR.
    You old Newtonian.
     
  9. RJBeery Natural Philosopher Valued Senior Member

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    Umm, possibly because the entities deciding whether or not the EH exists today are in that frame?

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  10. paddoboy Valued Senior Member

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    A quantum leap
    But the problem is that general relativity and quantum mechanics just don't play well together. Simply put, the equations of quantum mechanics can't describe gravity, whereas general relativity can only handle gravity.

    To talk about them both in situations where gravity is strong and quantum mechanics cannot be ignored, the best we can do at the moment is sticky-tape the equations together. Until we have a unified theory of gravity and the other forces, this is the best we can do.

    Stephen Hawking undertook one of the most famous attempts at this in the early 1970s. He wondered about what was happening at the event horizon in terms of quantum mechanics, where empty space is a seething mass of particles popping in and out of existence. At the horizon, this process separates particles, with some sucked into the central singularity, while their partners escape into space.




    Read more at: http://phys.org/news/2014-01-grey-black-hole-stephen-hawking.html#jCp


    Like I said before, I'm sure Hawking still sees BH's and their EH as real as they ever were.
    This seems to be a case of someone latching onto some new theme in quantum mechanics, simply for the reason of supporting a long held belief about BH's
    The past, the present and the future all exist depending on ones FoR. Just as one views distant BH's in the past, is no reason to assume they are not there now. In fact I see it as clutching at straws.
     
  11. nimbus Registered Senior Member

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    129
    Well, here’s the non-quantum angle of Wheeler, Taylor and Bertschinger.
    From my last link to ‘Exploring Black Holes ‘’ pick chapter ‘’Diving’’ Page 6-19

    My bold.


    As I said before, classically, in the in-faller’s frame there is no event horizon to be in or out off.
    Your wig powder is getting in your eyes sir Issac.
     
  12. Walter L. Wagner Cosmic Truth Seeker Valued Senior Member

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    Also quoted from the link: "But that's not the way science works, and it is important to remember that, while Hawking is clearly very smart – to quote the immortal Tammy Wynette in Stand By Your Man, "after all, he's just a man" – and just because he says something does not make it so."
     
  13. Farsight Valued Senior Member

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    That's a popscience myth I'm afraid. Virtual particles are "field quanta", like you divide the field into chunks and say each one is a virtual particle. See Matt Strassler's blog. They aren't short-lived real particles that pop in and out of existence like magic. And they aren't the same thing as vacuum fluctuations. Besides, gravitational time dilation is said to be infinite at the event horizon. So any "fluctuations" would take an infinite duration to occur. And since we know there's small dark massive things out there, maybe the question shouldn't be whether black holes exist, but whether Hawking radiation exists.

    Nimbus: there some material kicking around which has excellent credentials. But nevertheless is wrong. We've spoken about this before, see this. The issue with the "standard explanation" is that the infalling observer goes to the end of time and back and is in two places at once.
     
  14. dumbest man on earth Real Eyes Realize Real Lies Valued Senior Member

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    Not 100% sure here, but I don't believe the future actually exists - YET!

    Even, "depending on ones FoR" - "ones FoR" of any future is a mental construct or idea, basically - that has no Physical Reality.

    The Past seems to have existed - most of us can agree to that.

    The Present (or Now) seems to be currently existing - most of us can agree to that.

    The Future does not YET exist - in Physical Reality - in any way, shape or form...YET!

    Just as WLW pointed out in his Post (Bold by dmoe) :
     
    Last edited: Feb 2, 2014
  15. paddoboy Valued Senior Member

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    21,647

    All FoR's are valid whether a mental construct or not. Just as thought experiments to illustrate a point are valid.
    Past, present and future also all exist, although we can only ever be aware of one at a time.
    That possibility especially with the future, is well illustrated with thought experiments and actual experiments.
    The past present and future are part of the time line, and maybe accessed from different FoR's, depending on ones speed.

    ps: I wouldn't be too hard on yourself with the Tammy Wynette quote, [even though you quoted it dishonestly and insidiously and not as intended by Walter]...You have been known on the odd occasion to utter something that really is so.....take it easy ol chum!
     
    Last edited: Feb 2, 2014
  16. paddoboy Valued Senior Member

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    But of course Hawking isn't the only one that supports the reality of GR BH's...almost all reputable cosmologists do. [and continue to do]
    The latest 'thought experiment by Hawking is just a quantum artifact and even if shown to be true, [which it hasn't] does nothing at all to distract/discredit the BH concept, aside from the journalistic inspired sensationalist headlines.
    Why even Hawking radiation is yet to be confirmed.

    Our old mate Stephen does have a funny sense of humour at times.
     
  17. krash661 [MK6] transitioning scifi to reality Valued Senior Member

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    i have not read the actual paper yet (because it is advise to rather than all these media headliners articles), but i do not think hawking said black holes do not exist, but rather than the event horizon.
     
  18. paddoboy Valued Senior Member

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  19. paddoboy Valued Senior Member

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    It is probably also true that with any SMBH, and any infalling Astronaut, would have no indication or physical effects relating to the Astronaut crossing the EH, and probably would not be obvious even inside the EH. The gravitational tidal effects due to the space/time curvature is not as critical or as pronounced until a lot closer to the Singularity.
     
    Last edited: Feb 1, 2014
  20. paddoboy Valued Senior Member

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    And of course considering that all a BH effectively is, is space/time curvature caused by mass/density, and the EH is the circumference of where the escape velocity equals 300,000Kms/sec, so in the classical sense the EH most certainly exists, despite quantum connotations, as long as a GR BH is valid.
    And I have not yet seen anyone with any evidence to falsify the GR BH, or any evidence supporting a more likely concept based on the observations we see.
     
  21. dumbest man on earth Real Eyes Realize Real Lies Valued Senior Member

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    paddoboy, what, and also, how many future "FoR's are NOT a mental construct?

    Yes, thought experiments to illustrate a point are valid.

    However, a thought experiment - just like every other mental construct, or thought, idea or even dream - has no Physical Reality.

    When are "we" able to be "aware of" the Future, in any Physically Real Form - prior to the future becoming the present, or now, in Physical Reality?

    What actual experiments, in Physical Reality - utilize the future, in that they are completed and that future no longer utilized - prior to that future becoming the present, or now, in Physical Reality?

    Wow...so...reaching over and accessing my Guitar that I made some 20-years ago, and playing a song that I wrote at about the same time, in the Past - is somehow impossible, and "is even beyond the bounds of SR"?

    Other than the obvious proceeding into the future with the passage of "time" - how often and how "easy" is it for you to "access the future" - prior to the future becoming the present, or now, in Physical Reality?

    Without even getting into how...igno, err, no, I won't say that...stu, um, no, I won't say that, either...wrong the ^^above quoted^^ is. I mean because, in all actuality, I quoted : Walter L. Wagner's Post!

    Well...how can it NOT to be taken as anything than:
    - the ^^above quoted^^ is from : http://www.sciforums.com/announcement.php?f=30
     
    Last edited: Feb 2, 2014
  22. paddoboy Valued Senior Member

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    21,647

    My FoR at this moment...the FoR of the Astronauts occupying the ISS at this time....the FoR relevant to Curiosity and Opportunity.....The FoR relevant to New Horizons....





    Thought experiments are ways used to investigate the nature of everyday things and to gain knowledge to take us closer to reality...

    The quote that you referenced from Walter was not the full quote either......
    ""But that's not the way science works, and it is important to remember that, while Hawking is clearly very smart – to quote the immortal Tammy Wynette in Stand By Your Man, "after all, he's just a man" – and just because he says something does not make it so."
    The above was what was said in the article and was throwing water on the sensationalist headlines re BH's not existing.


    Out of the goodness of my heart I have taken the time to answer a couple of your questions, inspite of your agenda.
    The rest of the confused inane codswallop is not worthy of a science forum, and in effect is trolling. Unlike you, I do not need to highlight any part of my posts to illustrate its genuine nature.
    In effect, in this thread now, as well as the other one you have seen the need to troll, they are showing to all an sundry, that you really have some problem that needs attending to.



    As we all know, the paper and sensationalist headlines have not changed anything.
    BH's and their EH's do exist, in the past, now, and in the future.
    [At least Until someone describes the effects we see with a better model]


    Again, I truly doubt you have fooled or are fooling anyone.
     
    Last edited: Feb 2, 2014
  23. paddoboy Valued Senior Member

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    21,647
    Just released 5 hrs ago!

    Why Hawking is Wrong About Black Holes
    by BRIAN KOBERLEIN on FEBRUARY 1, 2014


    A recent paper by Stephen Hawking has created quite a stir, even leading Nature News to declare there are no black holes. As I wrote in an earlier post, that isn’t quite what Hawking claimed. But it is now clear that Hawking’s claim about black holes is wrong because the paradox he tries to address isn’t a paradox after all.

    It all comes down to what is known as the firewall paradox for black holes. The central feature of a black hole is its event horizon. The event horizon of a black hole is basically the point of no return when approaching a black hole. In Einstein’s theory of general relativity, the event horizon is where space and time are so warped by gravity that you can never escape. Cross the event horizon and you are forever trapped.

    This one-way nature of an event horizon has long been a challenge to understanding gravitational physics. For example, a black hole event horizon would seem to violate the laws of thermodynamics. One of the principles of thermodynamics is that nothing should have a temperature of absolute zero. Even very cold things radiate a little heat, but if a black hole traps light then it doesn’t give off any heat. So a black hole would have a temperature of zero, which shouldn’t be possible.

    Then in 1974 Stephen Hawking demonstrated that black holes do radiate light due to quantum mechanics. In quantum theory there are limits to what can be known about an object. For example, you cannot know an object’s exact energy. Because of this uncertainty, the energy of a system can fluctuate spontaneously, so long as its average remains constant. What Hawking demonstrated is that near the event horizon of a black hole pairs of particles can appear, where one particle becomes trapped within the event horizon (reducing the black holes mass slightly) while the other can escape as radiation (carrying away a bit of the black hole’s energy).

    While Hawking radiation solved one problem with black holes, it created another problem known as the firewall paradox. When quantum particles appear in pairs, they are entangled, meaning that they are connected in a quantum way. If one particle is captured by the black hole, and the other escapes, then the entangled nature of the pair is broken. In quantum mechanics, we would say that the particle pair appears in a pure state, and the event horizon would seem to break that state.


    Last year it was shown that if Hawking radiation is in a pure state, then either it cannot radiate in the way required by thermodynamics, or it would create a firewall of high energy particles near the surface of the event horizon. This is often called the firewall paradox because according to general relativity if you happen to be near the event horizon of a black hole you shouldn’t notice anything unusual. The fundamental idea of general relativity (the principle of equivalence) requires that if you are freely falling toward near the event horizon there shouldn’t be a raging firewall of high energy particles. In his paper, Hawking proposed a solution to this paradox by proposing that black holes don’t have event horizons. Instead they have apparent horizons that don’t require a firewall to obey thermodynamics. Hence the declaration of “no more black holes” in the popular press.

    But the firewall paradox only arises if Hawking radiation is in a pure state, and a paper last month by Sabine Hossenfelder shows that Hawking radiation is not in a pure state. In her paper, Hossenfelder shows that instead of being due to a pair of entangled particles, Hawking radiation is due to two pairs of entangled particles. One entangled pair gets trapped by the black hole, while the other entangled pair escapes. The process is similar to Hawking’s original proposal, but the Hawking particles are not in a pure state.


    So there’s no paradox. Black holes can radiate in a way that agrees with thermodynamics, and the region near the event horizon doesn’t have a firewall, just as general relativity requires. So Hawking’s proposal is a solution to a problem that doesn’t exist.

    http://www.universetoday.com/108870/why-hawking-is-wrong-about-black-holes/


    Please note: Permission has been previously obtained from "Universe Today" to post full articles as long as they are referenced,
     

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