Black Hole.... Not so Black

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

  1. paddoboy Valued Senior Member

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    21,225
    Agreed....
    Just to add though, when we talk of a Singularity, we are not actually talking of any "infinite" quantities like spacetime curvature, or density, rather we are referring to a domain where it "MAY" lead to these infinite quantities.
     
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  3. paddoboy Valued Senior Member

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    Here's another nice descriptive link re Singularities.....

    http://www.einstein-online.info/spotlights/singularities
    where it says in part.....
    """"""""""""""""""""""""""""""""""""""""""""""""""""
    "According to the present standard definition, a spacetime singularity can be identified by examining particles in free fall - both ordinary matter particles and massless particles like photons. In general relativity, such freely falling particles, which by definition are only affected by gravity and by no other forces, move on the straightest possible lines through spacetime, on what mathematicians call geodesics. A spacetime singularity is said to occur wherever a freely falling particle suddenly pops out of existence! Since the particle travels through spacetime in the straightest possible way, namely on a geodesic, and since the abrupt end of the particle's existence corresponds to the unexpected end of that geodesic motion, this phenomenon is called geodesic incompleteness"."
    """"""""""""""""""""""""""""""""""""""""""""""""""""

    The above is by my reckoning saying that once this particle "pops out of existence" is the same as saying once our physical laws and GR are unable to predict at that level of spacetime curvature and gravity.....[quantum gravity and the Planck scale]
    Any comment on my Interpretation by anyone?



    and another here......
    http://www.askamathematician.com/2012/09/q-what-are-singularities-do-they-exist-in-nature/
    where it says.....
    """"""""""""""""""""""""""""""""""""""""""""""""""""""""""
    "I suspect that what we call the singularity in black holes either doesn’t exist (there is some law/effect we don’t know about) or, if cosmic censorship is true, the nature of that singularity both doesn’t matter and can’t be known, since it can never interact with the rest of the universe. There are some theories (guesses) that would fix the whole “black hole singularity problem” (like spacetime can only get so stretched, or some form of “quantum fuzziness”), but in all likelihood this is just one of those questions that may never be completely resolved".
    """"""""""""""""""""""""""""""""""""""""""""""""""""""""""

    Which seems to be agreeing with what Professor Carlip said. [and little old me

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    Last edited: Dec 31, 2014
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  5. paddoboy Valued Senior Member

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    And this.......
    http://en.wikipedia.org/wiki/Quantum_singularity
    where it says......

    "In science fiction, the term quantum singularity is used to refer to many different phenomena, which often approximately resemble a gravitational singularity in the scientific sense in that they are massive, localized distortions of space and time. The name invokes one of the most fundamental problems remaining in modern physics: the difficulty in merging Einstein's Theory of Relativity (which includes singularities within its models of black holes) and quantum mechanics. In fact, since singularities are infinitely small according to relativity, they are expected to be quantum mechanical by their nature; a theory of quantum gravity would be required to describe this behavior, and no such theory has yet been completed.[1] On the other hand, only one kind of singularity has ever been observed (black holes), and due to the mass dependent, stable radius of the connected event horizon, it is currently unknown if this kind of singularity actually approaches or even drops below scales relevant to quantum mechanics."
     
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  7. RajeshTrivedi Valued Senior Member

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    Everything else in your post is ok....but not the above part with respect to any singularity..

    Singularity is always mathematical, yes there is a physical manifestation of singularity inside EH, but even then it cannot be associated with any lengths or physical dimensions...
     
  8. OnlyMe Valued Senior Member

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    3,914
    Do you know how to read?
     
  9. paddoboy Valued Senior Member

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    21,225


    Your recommendation or otherwise holds no water as far as I'm concerned.
    The whole point is we do not know, plus the fact that the Planck/Quantum scale, and Singularity are the parameters of where our current best model and predictions break down.


    http://www.einstein-online.info/spotlights/singularities
    "According to the present standard definition, a spacetime singularity can be identified by examining particles in free fall - both ordinary matter particles and massless particles like photons. In general relativity, such freely falling particles, which by definition are only affected by gravity and by no other forces, move on the straightest possible lines through spacetime, on what mathematicians callgeodesics. A spacetime singularity is said to occur wherever a freely falling particle suddenly pops out of existence! Since the particle travels through spacetime in the straightest possible way, namely on a geodesic, and since the abrupt end of the particle's existence corresponds to the unexpected end of that geodesic motion, this phenomenon is called geodesic incompleteness".
    http://www.einstein-online.info/spotlights/singularities
     
  10. RajeshTrivedi Valued Senior Member

    Messages:
    1,366
    Paddoboy, I really admire your enthusiasm for mainstream and really appreciate the hard-work put in by you, in sourcing the references and links......None of the links supplied by you supports the view that singularity is associated with Planck's level..... By now you are very clear that singularity cannot be associated with length or any level...Pl do not push it further.

    If you care then I wish to clarify further with respect to BB / BH / Planck's level as below...this is not my theory, this is all mainstream..

    1. Planck's length can be simply derived from Schwarzschild (Rs) radius (Relativity) vis a viz De Broglie Wave Length (Lambda) (Quantum Mechanics) associated with a particle. If you note Rs is directly proportional to mass, while Lambda is inversely proportional to mass...so there must to be an inflection point where both Rs and lambda are same for a given mass...thats the hypothesis and by equating both Rs and Lambda we get the Lp, Mp and Tp. The problem got compounded by the fact that Lp and Tp are extremely small but Mp is not so small and there are sub atomic particles of lesser mass than Mp, this is a bottleneck in accepting Lp and Tp as the quanta (smallest discrete level for Lp and Tp).

    2. Regarding BB before 10^-43 Sec.....

    You have been quoting this figure of 10^-43 in many threads and many posts.... This 10^-43 seconds is actually Tp...and we are hopeful that one day this Tp may be theorized and accepted as absolute time quanta...so it makes no sense to talk about a time between 0 to 10^-43 seconds.. So as you say we do not know anything about T < 10^-43 seconds is fine.....but you have many times stated that may be QGT as and when comes will tell us prior to this time....it may not....simply because this Tp may be taken as the smallest quanta of time and time can be accepted as discrete instead of continuous variable....


    3. Regarding BH Singularity

    Once the radius of an object is less than Rs (EH Boundary), we really do not know where the mass goes...because mathematics yields singularity...which cannot interact with Physical world...so we have to contend with the shroud of EH....

    Now suppose we hypothesize and accept that (Planck's Length) Lp is the lowest quanta of length....then the natural corollary is that the entire mass will go and reside inside a sphere of Lp......No singularity..... So in either case we cannot associate singularity with any dimension or any level.....It is purely mathematical expression...possibly as on date our inability to understand the physical world in that domain...
     
  11. OnlyMe Valued Senior Member

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    3,914
    I can't extract text from a quote in another post on my iPad, but tashja, posted a reply from Prof. Carlip in another thread, that at least in part addresses your mistake. You can find the professor's answer to a different question.., that I believe overlaps the issue discussed here, in tashja's post quote below. (Don't see much of the post here, but the link to the original post should work.)

     
  12. tashja Registered Senior Member

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    715
    See this very interesting reply from a moderator on another forum:

     
  13. RajeshTrivedi Valued Senior Member

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    1,366
    I thought you wrote everything in English !! Sorry my friends told me that in fact it was greek..
     
  14. OnlyMe Valued Senior Member

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    Tashja, that is an example where Peter was talking from a purely mathematical and theoretical postion.

    Even though Prof. Carlip never used the word singularity his comments about quantum gravity and lengths, can and in some cases are relevant to how the word singularity is used. Rajesh is just stuck on the mathematical definition and use.

    Definitions, ideas and even how we use words evolve over time.
     
  15. tashja Registered Senior Member

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    715
    So Rajesh's mathematical definition and usage of a singularity is correct?
     
  16. paddoboy Valued Senior Member

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    21,225
    My enthusiasm for mainstream cosmology is supported by the evidence and data available from state of the art probes and other vast engineering projects, rather then some inane desire to posture and present some long faded aspect of thinking for yourself...yourself meaning you.
    When you have some qualifications, when you accept that the knowledge of giants of the present and past, will always surpass your miserable thimble full knowledge, you may begin to realise that people are laughing at you.
    The BH Singularity presents itself when our current best model fails, which happens to be at the Planck/Quantum realm.
    .


    The rest of your unsupported diatribe is not worth commenting on, until at least you are able to supply a reference or link.
    The following sums up fairly well....

    "In science fiction, the term quantum singularity is used to refer to many different phenomena, which often approximately resemble agravitational singularity in the scientific sense in that they are massive, localized distortions of space and time. The name invokes one of the most fundamental problems remaining in modern physics: the difficulty in merging Einstein's Theory of Relativity (which includes singularities within its models of black holes) and quantum mechanics. In fact, since singularities are infinitely small according to relativity, they are expected to be quantum mechanical by their nature; a theory of quantum gravity would be required to describe this behavior, and no such theory has yet been completed.[1] On the other hand, only one kind of singularity has ever been observed (black holes), and due to the mass dependent, stable radius of the connected event horizon, it is currently unknown if this kind of singularity actually approaches or even drops below scales relevant to quantum mechanics."
    http://en.wikipedia.org/wiki/Quantum_singularity


    Oh and by the way...No effort at all supplying the links supporting what I have said...They are everywhere.
    Better luck on your next anti mainstream "I think for myself campaign" crusade.
     
  17. paddoboy Valued Senior Member

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    21,225

    It's one narrow definition that ignores many other theoretical aspects.
     
  18. tashja Registered Senior Member

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    715
    The topic is about BHs, so my understanding is that Rajesh is referring to transplanckian singularities, no?
     
  19. paddoboy Valued Senior Member

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    21,225

    Rajesh's claim is that a BH Singularity [and the BB Singularity] has no connection with the Planck/Quantum scale.
    He is totally wrong and that is evident from Professor Carlip's reply and the many links I have given.
     
  20. paddoboy Valued Senior Member

    Messages:
    21,225

    In all honesty, I'm not sure what he is claiming, but this thread 235 posts ago, reflected his opinion that BH's do not exist, and like our other doubters, he could still not give any cause or reason as to what could cause the effects on spacetime and matter/energy, that leads us to accept BH's [Gravitationally Completely Collapsed Objects] as reality.

    And the most outstanding aspect of his ranting, is despite me asking many many times, he has been unable to supply any link supporting his concept.
     
  21. paddoboy Valued Senior Member

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    21,225
    I failed to mention his other great error in judgement.
    He refuses to accept that a future QGT, may well eliminate the Singularity, or push it back further. He seems to think that the Planck ultimate minimal quantities are an absolute fact of life.
    We are all pushing shit up hill, until at least we can get him to realise his error in that rather elementary bit.
    [That has also been supported [the fact that the Planck quantities are only hypothetical] in one of my many links.
     
  22. tashja Registered Senior Member

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    715
    lol. OK. Let's wait for Rajesh to clarify his position and maybe I can ask a Prof. to help us with some answers.

    Rajesh, see if these answers help:

     
  23. RajeshTrivedi Valued Senior Member

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    1,366
    Pl re read my post # 227...It is not what you are stating as above..Pl do not quote or misrepresent other's views to justify your stand..
     

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