Neutron Star to Black Hole

Discussion in 'Astronomy, Exobiology, & Cosmology' started by RajeshTrivedi, Jan 12, 2015.

  1. RajeshTrivedi Valued Senior Member

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    Ignoring the unnecessary noise made by you, possibly to save your friend Paddoboy....

    The entire Kerr Geometry Rotates ??? What all you are including in your Kerr Geometry ?? Do not say conveniently that you did not mean r <Rs (inner EH)..

    The Rotational Energy of the Neutron Star is with the rotating mass of the neutron Star, the rotational energy of the Kerr BH is associated with the Ergo Sphere, thats the point that......in the transition stage from NS to BH when star r>Rs, energy is within r, but when r < Rs.....where does this energy go ?? Many links now you will refer will tell you that the rotational energy of the Kerr BH is associated with ErgoSphere, but you guys never bothered to understand that how and under what process it so happens ??
     
    Last edited: Jan 13, 2015
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  3. RajeshTrivedi Valued Senior Member

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    Kerr Geometry...actually you are so glued to mathematics...that you have forgotten that angular momentum cannot be associated with a geometry unlike Energy.... and where is the mass in Black hole ?? So what are you associating angular momentum with ?? What is the physical significance of Rotating BH in a sense that mass is shrouded by EH ?? These are some of the questions..
     
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  5. OnlyMe Valued Senior Member

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    Look up the scientific definition of hypothesis. Penrose theorized a process through which energy could be extracted from a spinning black hole.

    In science a hypothesis must be testable. A theory, while it must still fall within the context of the scientific process, is not as restricted. We develop hypotheses to test a theory.

    We cannot test any mechanism that would extract energy from a black hole's angular momentum or any spin down of that angular momentum that might result.

    Penrose presented a theory supported by some scientific reasoning. What you have and seem to continue to present, is more in line with random speculation.

    As I have mentioned repeatedly, there is nothing wrong with speculation, as long as one knows that it is speculation. It is important to keep a firm grasp on the difference between what is known or proven to be and what is theoretical or logical speculation.., or just plain random speculation in this case.

    As example, I could offer some speculation about the implications of theoretical work suggesting a fundamental orgin of inertia and carry that even further via the equivalence principle, to suggest that graviation is emergent from inertia.., but all of that would be speculation, not even rising to the level of theory, and certainly never rising to the level of a testable hypothesis...

    Schwartzchild black holes are not known to exist and most of what we do know about black holes, apart from the orbital mechanics of stars observed to orbit what we believe are black holes, remains theoretical at best.

    I thought, because I do not study the thread discussion I cannot say with certainty.., that you were supporting the concept of a mathematical point singularity, as opposed to some other physical composition which might be associated with a black hole. If that is the case, you cannot discard the idea that spacetime itself inside of the event horizon, or even outside of it for that matter, has some angular momentum or something equivalent and reference Penrose, as you did.., because you cannot associate any angular momentum with a point, which is what a mathematical point singularity is... I won't carry that further as it opens a whole different can of worms...

    I am not sure you understand what you reference or even the implications of what you are saying. It seems to me that you are mismatching concepts, that don't really or easily get along.
     
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  7. paddoboy Valued Senior Member

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    My statements, all of them remain as is.
    Like you, I don't have any qualifications as I have often stated.
    Unlike you, in general I adhere to the accepted mainstream logical versions.
    One "out of context" statement, from one professor out of many, does not support your position.
    Now again, show some link or reference supporting your position, which obviously you cannot do.
    Again, my statements remain.
     
    Last edited: Jan 13, 2015
  8. paddoboy Valued Senior Member

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    Thanks brucep.....This soul Ravesh is obviously another constant theorist or chinglu.

    Please Register or Log in to view the hidden image!


    Has nothing, knows nothing, cannot accept mainstream links on his own admission, and obviously is just another fringe dwelling troll, envious of all that science/cosmology is, and has done, and will do.
     
  9. paddoboy Valued Senior Member

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    Interpretation:
    I'm not Interested in the truth, especially if it supports paddoboy.

    The EH is not a physical thing. It is simply a limit, or parameter of critically curved spacetime, where the escape velocity equals "c"
     
  10. brucep Valued Senior Member

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    You're making a fool of yourself. Put a cork in it. I've studied the physics and understand it. You haven't so your opinion is bullshit nonsense. Troll on idiot wind.
     
  11. brucep Valued Senior Member

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    Last edited: Jan 13, 2015
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  12. brucep Valued Senior Member

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    Deleted
     
  13. brucep Valued Senior Member

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    Deleted.
    It's a theoretical prediction whether it's empirically testable or not. The prediction process is important because it lets us know we might want to test it empirically if possible. Most being possible. The ring singularity is a consequence of the rotation and because of it's geometry 'all geodesics do not end there'. The Penrose process is a theoretical prediction. If you could mine all the rotational energy so that it no longer rotates it would be a Schwarzschild black hole. That would be the prediction.
     
  14. OnlyMe Valued Senior Member

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    Bruce I don't have any real issue with your above post but a question and a comment.

    The question, what's the difference in meaning between using theorized in that context and theoretically testable? My intent in that post was to distinguish between hypothesis and theory, in the post I responded to.

    The comment is and was that there is no way to test the theory. That was not meant as invalidating. It again was in reference to the post I was responding to.

    Too often the in some of these discussions the words speculate, theory and hoypothesis are used interchangeably and sometime it is not clear that the author understands the differences.
     
  15. KilljoyKlown Whatever Valued Senior Member

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    I've read that neutron stars do lose some rotational energy over a great deal of time. We would probably need millions of years to measure it. As far as the size goes thanks for correcting me. I was only using that as a (ballpark) example and didn't feel the need to look it up. The question about BH's being able to lose all their rotational energy might be a useful math concept the same as a BH evaporating via Hawking radiation until it was gone.
     
  16. brucep Valued Senior Member

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    It's a theoretical prediction derived from the theory. Such as the prediction for Einstein orbits. They always precess while the prediction derived from Newton says they never precess. The actual physics. I always say and mean the theoretical prediction based on the actual physics. I don't have any hypothesis so it doesn't get mentioned much from me. I should have said naturally precess. Any other precessing is associated with perturbations. Based on the actual physics that Einstein orbits naturally precess we can calculate the famous prediction for Mercury.
    BTW that's a major problem for the cranks. Their predictions are never based on actual physics. Instead on some illiterate hypothesis.
     
    Last edited: Jan 13, 2015
  17. RajeshTrivedi Valued Senior Member

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    I have no reason to disbelieve that you have studied Physics. I am not making a fool of myself, a person who asks questions may not be a fool or dumb, I am asking question from a lower level of understanding and you are answering from a "self assumed" teacherescue position of understanding....chances of your making a fool yourself are much higher and you have almost triggered the process.

    I understand, many a times our response/opinion is off the cuff, out of memory, and there may be some slips/mistakes/oversight and even pure lack of understanding (old notion), but as soon as it is brought to notice or comes to notice it must be corrected...like you may wish to correct your statement that Entire Kerr Geometry Spins. You have an option to glue to this statement the way Paddoboy is gluing to his Plancks Level..first he said singularity is at Planck's Length, then he shifted to Planck's level, then he brought in quantum level, then he shifted to Plancks/Quantum Level, then he brought in region around Planck's scale, then he ...what not...Now 'OnlyMe" is also attempting to tell him that QM/PL has no business with singularity...but Paddo is still stuck......See how he cling to your me bashing post, he listens to you, if you have studied Physics then tell him that singularity in the context has no business with PL, that inside of EH does not spin, that ring singularity does not shift to r = 0 when BH stops spinning....

    And one last thing...You cannot win an argument by calling others name...you are trying that.
     
  18. RajeshTrivedi Valued Senior Member

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    I must reframe the main point of discussion...

    Neutron Star has great amount of Rotational Kinetic Energy and Angular Momentum. The collapse to BH (lets focus on due to accretion by Neutron Star) takes less than a second and of course at first a Rotating BH is formed. What happens to this Rotational Kinetic Energy and Angular Momentum ?

    I would add further....since inside of inner EH cannot interact with Physical world so the Rotational Energy is associated with Ergosphere....Energy can be associated....but what about angular momentum...It can only be associated with mass...whose whereabouts are not known ? Moreover as long as the star was NS, the rotational energy was with the mass (till r = Rs), as soon as it collapse this rotational kinetic energy got associated with Ergosphere (r > Rs)..see the point is mass is collapsing towards r--->0 but Rotational energy is moving outward to outer horizon...How ??
     
    Last edited: Jan 14, 2015
  19. paddoboy Valued Senior Member

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    You are the one that has an option. Brucep and myself have stuck to accepted theoretical concepts within GR.
    That certainly includes the Singularity existing and beginning at the Plank/quantum region/level. You see although the Planck construct is a mathematically theoretical scenario, its proposed to exist at the quantum/Singularity level....Where GR breaks down.
    If I did use the term Planck length [ and I don't think I did] I was wrong, but you could show me where, but knowing your record, I guess you won't
    Only Me is actually arguing against your hypothetical not mine, except in the case of some terminology.
    In fact we agree on most all, and that is not the case with yourself.
    And of course the entire Kerr geometry certainly does spin, unless you can give a reasonable reputable link to the contrary? I guess going on your past record again you can't.
    You need to also move yourself from that obvious way of trolls, in handling the truth lightly?
    That does nothing for your self esteem.

    r
     
  20. RajeshTrivedi Valued Senior Member

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  21. paddoboy Valued Senior Member

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    Some points you need to consider......
    [1] The accepted theory is that the whole Kerr metric rotates.
    [2]All any BH in effect is, is curved spacetime, with the mass at the center, according to accepted GR.
    [3] All the EH is, is a non physical parameter of spacetime curvature, where the escape velocity equals "c"
    [4] The rotational energy is associated with mass [hence the ring Singularity formation] the spacetime within the EH proper, and the Lense Thirring/dragging effect obvious inside the "static limit" of the ergosphere and also outside to a lesser degree.
    [5] If a Kerr BH loses spin through interaction in feeding or any other method, the ring singularity resorts to standard Schwarzchild singularity obvious at the level of Planck scale/quantum level.
     
  22. paddoboy Valued Senior Member

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    Now just as obviously Only Me has addressed some of your misconceptions just as brucep has and Q-reeus in the other thread before them and a myriad of professors also.
    It's really about time you cut the pedant and nonsense, and sit back and examine the whole picture.
     
  23. RajeshTrivedi Valued Senior Member

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    Paddoboy,

    There are 3 main components to Planck's level (wiki would list so many other derived ones..), Planck's Length, Planck's Time, Planck's Mass. So if at all singularity of a BH can be attached to Planck's level, it can be attached to any or all of these 3 parameters Lp, Tp and Mp...

    Tp makes no sense for a BH, Mp is too small as compared to BH mass, that leaves Lp.....Now you agree that BH singularity cannot be attached to Lp....So please tell me and others which part of BH singularity you are associating with Planck's level....

    I do not think you need a better reference then your own admission...

    Edit: Planck's Energy links with Mp
     

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