Black Hole.... Not so Black

Discussion in 'Astronomy, Exobiology, & Cosmology' started by RajeshTrivedi, Oct 1, 2014.

  1. RajeshTrivedi Valued Senior Member

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    you are a nice guy, but there is something amiss in your thinking...

    1. You claim to be a layman.
    2. But you have in your mind something beyond present day mainstream cosmology.
    3. You get exceedingly defensive about your knowledge and self, and generally get into copy - paste kind of posts.
    4. You are a die hard supporter of mainstream.

    I accept things but I have an independent thinking mind, and I am not afraid of bringing my opinion forward. I do not have the extreme acceptance of mainstream like you have and neither I boast of thinking beyond present day mainstream. you just contradicted yourself.
     
    Last edited: Dec 22, 2014
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  3. OnlyMe Valued Senior Member

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    The composition.., internal structure of a neutron star is hypothetical/theoretical, we have no direct evidence upon which to establish any statement of fact, with respect to anything we cannot observe and measure. Including language like that in bold below raises what might be a valid theoretical statement, to one verging on a statement of fact, or known reality.

    Here and in my earlier comment I am not disagreeing with the theory, which I make no comment one way or the other on, only on the inclusion of language that implies that what remains theory has somehow been proven.
     
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  5. RajeshTrivedi Valued Senior Member

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    I cannot dispute that, because in schwarzschild metric, the time becomes spatial inside EH and hence it must move towards singularity.

    My point one for the argument is that Schwarzschild radius is proportional to mass, that means the density of a star (just at Sch) is inversely proportional to the square of the mass, and it can be inferred that density of a corresponding BH reduces faster as the mass of the star increases. Theoretically it is imaginable that a BH density can be as low as the density of air in our living room, so what kind of force or pressure we are talking about inside Sch Radius with such a comfortable density. I feel lot more work is required before we say that BH is the ultimate natural object.
     
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  7. RajeshTrivedi Valued Senior Member

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    Think of it from different perspective, we reach to BH after surpassing neutron star, but the density of neutron star is always very very high (around 10^18), then how come density of BH be lower than of neutron star ?
     
  8. OnlyMe Valued Senior Member

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    Once the density of the mass within the event horizon is sufficient that the total mass required to result in the formation of an event horizon, is itself within the event horizon, density is no longer an issue... I.E. Once an event horizon has formed mass density only determines how far inside the event horizon the black hole surface is.
     
  9. paddoboy Valued Senior Member

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    Sure I do! As do many theoretical physicists....The difference which you cunningly ignore is I don't put them as fact...and neither do the professional physicists.

    Defensive? Die hard supporter???

    Please Register or Log in to view the hidden image!


    No not in any stretch of the imagination. I simply ask for genuine evidence supporting new concepts, insistence on following accepted scientific methodology, and getting it properly peer reviewed.
    All our current well accepted theories were at one time just hypothesis...They all had to run the gauntlet then undergo peer review.
    They were eventually accepted as mainstream models, because in the opinion of the majority, those new theories were the most logical and matched the observational and experimental data far better then any thing else.
    In most cases, applying common sense, logic and reason, I align with that majority.
    I don't automatically ignore accepted scientific models, just for the sake of being different and in promoting some "I thought of it myself" paranoia, that certain ill informed people like to wear as a badge of honour.
    But I'm sure you have been told all this before. So why do you continue to ignore it?


    You need to be more humble and accept the fact that the chances that you, as an unqualified, unprofessional amateur, just like myself, being right and usurping the experience professionals, that have at their disposal, state of the art technology like the HST, LHC, WMAP, Spitzer, Planck, and a myriad of other information gathering probes, while being non zero, is close to it.
    That's what you need to live with.



    No, its you who has contradicted yourself. I accept in the main, mainstream models, because they are best supported based on logic, reason and evidence.
    I also know the difference between accepted mainstream theories, and speculative scenarios that I may have, which are all beyond the range of applicability of those mainstream models. You do not it appears.
     
  10. paddoboy Valued Senior Member

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    Because the mass that makes up a BH, is squeezed to the quantum/Planck level we call a singularity. The rest is just critically curved spacetime.
    A Neutron star on the other hand is a solid ball of degenerate matter without an EH.
     
  11. Q-reeus Valued Senior Member

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    You unfairly highlighted just one part of quoted passage, ignoring e.g. the very next sentence. And even that selective quote had in it the word 'almost'. You also made no comment on the 2nd linked article. I'm unclear as to your overall position here, but maybe you could tell me just what if anything in astronomy/cosmology you consider as proven beyond reasonable doubt. What about e.g. that stars shine via fusion in their cores? Only speculative theory? After all, no-one has sent an indestructible probe into even our sun's interior to prove fusion is powering it. Give us a list of what you think is proven beyond reasonable doubt.
     
  12. Q-reeus Valued Senior Member

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    BH surface inside EH? There is no surface to a BH. Only the EH boundary. And in fact that is considered the giveaway 'acid test' of 'proving' that accreting matter surrounding a candidate BH in-falls in a manner that indicates no physical surface exists. That some alternate gravity theories predict essentially the same observations as to spectral emissions is typically not mentioned, but that's another story.
     
  13. Q-reeus Valued Senior Member

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    Density of a BH is fairly meaningless given there is no 'stuff' present as there is for say a NS. Regardless though of how large is the supposed EH, according to Schwarzschild metric the proper acceleration required to hover at such EH is always infinite. Implying infinite stresses no material could withstand.
     
  14. paddoboy Valued Senior Member

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    Yep, agreed and what I said at post 167.
    You mention hovering at the EH, presumably just this side of it.
    Photons of light being emitted from an infalling body, directly radially away, would appear to be hovering near the EH, never secumbing, but never quite getting away.
    Light emitted at any other angle, will arc back and fall past the EH onto oblivion.
     
  15. theorist-constant12345 Banned Banned

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    2,660
    I think you have your quote from me and it was not me who wrote that , although I agree with it.

    ''You need to be more humble and accept the fact that the chances that you, as an unqualified, unprofessional amateur, just like myself, being right and usurping the experience professionals, that have at their disposal, state of the art technology like the HST, LHC, WMAP, Spitzer, Planck, and a myriad of other information gathering probes, while being non zero, is close to it.
    That's what you need to live with.''

    Well in answer to this, I know I am right, by simple observation and realism.
     
  16. OnlyMe Valued Senior Member

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    I perhaps too often get caught by the certainty I see in some posts. This case including "almost" in a statement that otherwise is about certainty does not change the underlying message... And the next sentence in that original post begins with, "All reasonable calculations..," which trivializes all other theoretical work involving the cores of neutron stars. It was not so long ago that we discussed here the implications of a paper that focused on the idea that the core of a neutron star consisted of cubic neutronim... Did not sound like a super fluid or super conductor....

    It may not have been your intent but that post did to me come across as a statement of absolutes and a rejection of all other theoretical work involving the composition of neutron Stars.

    You then jump to comparrison questions about fusion in stars.., fusion is something we have been able to work with. Fusion itself is no longer theoretical and we do know as a matter of experience that it can be associated with pressure and temperature. Things that extreme gravitational pressure would create. These are not equivalent issues. Yes there is much about the internal dynamics of even a common star we do not understand, but it is not even in the same ballpark.., theoretically as is the composition of a neutron star.
     
    Last edited: Dec 23, 2014
  17. OnlyMe Valued Senior Member

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    A point singularity has no surface... True! But you won't find many physicists today that believe the point singularity exists anywhere other than, as a theory. Even GR can't resolves the problems that arise from the concept of point singularities.

    In some sense your above statement as it begins, is accurate. However, it is pure speculation at this time to even try to imagine what lies within the event horizon of a black hole. For us now, the event horizon is the line where theory becomes consumed by imagination/speculation. The laws of physics as we know them do not seem to be the same.., theoretically.., inside of an event horizon....., so how can we know with certainty, exactly what the composition of the mass involved is?

    You do agree, that a black hole does still have mass, right?... We just cannot say what form that mass is in that results in what we call a black hole. We don't even know the exact nature of the composition of a neutron star, after all.

    You mentioned "observations of spectral emissions". If you included a link I missed it, but... Keep in mind that even the conclusions drawn from that sort of cosmological observation, are heavily influenced and even sometimes distorted by the theoretical basis, the observers start with. What that sort of observational evidence originates from is itself theoretical. Whether it tells us something about the black hole itself or just something more about what is happening outside the event horizon, is not really known. It is theorized!
     
  18. RajeshTrivedi Valued Senior Member

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    Planck level is not at all singularity ? Neither we can associate singularity with Planck level.
     
  19. RajeshTrivedi Valued Senior Member

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    Kindly authenticate this statement...
     
  20. RajeshTrivedi Valued Senior Member

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    Where have you put ??

    you are missing something again paddoboy.....these HST,LHC, WMAP they are instruments for observations, for collecting data. Science works both way...that is theorise and then observe extensively......observation and then theorise....Give some explicit respect to our forefathers who had exemplary knowledge of cosmology centuries ago without all these high tech instruments.



    What do you mean ?? How can a self claimed layman think beyond the mainstream models ? This is the contradiction in you which I was referring to.
     
  21. paddoboy Valued Senior Member

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    The world knows you are wrong, by the same simple observational data that you misinterpret or manufacture for your cause...whatever that is.
     
  22. paddoboy Valued Senior Member

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    Ignoring the obvious as to what I put as theory or near fact, when it is down many times in black and white, is really dumb.
    But that seems to be relevant with most of your posts....Ignoring what is known.


    No, once again, I'm missing nothing, and you are continually being obtuse.
    Once again, the instruments I have mentioned, are available to the professional scientists, and not to rank amateurs with delusions of grandeur like yourself. They then logically deduce and predict outcomes, and formulise theories via the scientific method and then peer review, which you avoid.
    Part of that scientific method is standing on the shoulders of giants of the present and past, or the knowledge of our forefathers that you hypocritically raised, since you like our other troubled alternative hypothesis nuts, ignore that same knowledge, when it contradicts what fairy tales you yourself have dreamed up.




    Easy, as any level headed logical person would know. eg: I have speculative thoughts as I have told you about what the BB is, and the how and why of it.
    I also have speculative thoughts on BH Singularities, ERB's and baby Universes off shoots.
    They are just speculation. I do not claim them as faitre comlei certainties.
    Why can you not see that? How can you see that as any contradiction? Contradicting what? Why are you so confused?



    You really seem to not want to understand like that other nut that is infesting the forum of late...
    The statement by Q-reeus that "Density of a BH is fairly meaningless" refers to the information I have already given you, that in line with GR, any mass that collapses to its Schwarzchild radius, will have no other choice then to keep collapsing to the Planck/Quantum level.
    So once again, as I have also told you before, a BH in essence is nothing but critically curved spacetime, with a point Singularity at the center, where all the mass is.
    Again, since this has been mentioned to you at least three times from memory, one can only deduce you are again being obviously obtuse.

    Who said the Planck level was a Singularity?
    I did say, "Because the mass that makes up a BH, is squeezed to the quantum/Planck level we call a singularity. The rest is just critically curved spacetime."
    Let me detail in as simplistic as possible terms.
    [1] The mass of a BH is squeezed within the Planck/Quantume level.[ see my Schwarzchild radius comment]
    [2] GR fails at the Planck/Quantum level, or to put that another way, the Planck/Quantum level is outside the parameters of GR.
    [3] Therefor we call it a mathematical Singularity.
    [4] Most mainstream cosmologists also believe that once we have a QGT that can be observationally or experimentally validated, it will reveal a surface of sorts beyond that Planck/Quantum level, and either eliminate the present mathematical Singularity, or push it back even further.
    [5] Other cosmologists [and humble layman such as myself] have also speculated that maybe this mathematical Singularity at the Planck/Quantum level, may lead via a ERB to an out pouring [white hole] of spacetime and matter/energy, creating another bubble Universe.

    Surely even you can understand that?
     
  23. paddoboy Valued Senior Member

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    And even the EH is not a surface of any sort, just the parameter at which the escape velocity of light exceeds "c"
    Any possible surface, is within the Planck/Quantum scale and the Singularity.
    A future validated QGT may reveal a surface of sorts. I'm sure that is what "Only Me" is inferring.
     

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