Neutron Star

Discussion in 'Astronomy, Exobiology, & Cosmology' started by RajeshTrivedi, Apr 7, 2015.

  1. RajeshTrivedi Valued Senior Member

    No, I do not agree with your argument in totality.....

    Neither I am saying that what I have suggested is not open for discussions (or tearing apart). You are mixing up many things.......

    1. GR does not talk about any finite or infinite pressure.
    2. There is not much of consensus established Physics inside EH, as on date.
    3. LQG research (Whatever you are suggesting) as per you, as on date speculation only, so lets wait for ultimate conclusion.

    And of course I would agree with you, if anything gets resolved at Plancks length for a even a solar mass object, then no degeneracy pressure is expected to sustain that range......but this resolution is speculation as you are saying.

    I think the better argument against my paper is, start with a 1 million solar mass core, calculate the Neutron Degeneracy Pressure and also the Gravitational Pressure inside EH and prove that Pg > NDP (from Rs < r < 0). (Please note that there is no discontinuity in any of the parameters at r = Rs, cross over, so if there is a finite gravitational pressure at Rs+, then suddenly it is not going to become infinite at Rs-....this alone offers possibility for some kind of stability.

    And by the way, the paper offers few other points as well, apart from existence of BNS, do you agree with them?

    1. A visible NS can have a mass range of 1.4 to 2.65.
    2. A visible Quark Star (further possible degeneration) is possible only in the range 2.65 - 3.24 Solar Mass.
    3. A BH minimum mass is 3.24 Solar Mass.
    Last edited: Apr 9, 2015
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  3. Q-reeus Valued Senior Member

    My #29 has adequately covered that. Yes, inasmuch as you posit a stable i.e. not collapsing black NS, GR most certainly does predict infinite pressure. Given degeneracy pressure cannot be infinite, your only choice to save black NS is to throw out GR and adopt some radically different theory of gravity. Take some time and deeply think about it. Be prepared to let go. As for the remainder of your points, sorry but I'm not interested in arguing around in circles.
    danshawen likes this.
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  5. danshawen Valued Senior Member

    Yes, this is sounding better all the time. Nice analysis. Good luck.
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  7. brucep Valued Senior Member

    You don't know what you're talking about Rajesh. You shouldn't be making comments about what GR predicts since you don't have any scholarship to work with. Using GR we can do all analysis up to r=0. GR predicts there's no black neutron star between r=2M and r=0 regardless what you think. What you think doesn't have anything to do with the science. If a neutron star falls into the black hole we can determine its path and the the proper time, in this case the proper tick rate for a clock on the falling neutron star, it takes to reach r=0. So let's see if you can predict when the neutron star will be completely pulverized. Get it? Completely pulverized and part of the 'quantum foam' that John A. Wheeler coined for r=0.
  8. RajeshTrivedi Valued Senior Member


    What is your opinion about GR ?? Is there any change in last couple of months ?

    Coming to the point, in the OP itself, I have very clearly stated that peer review published papers, start their public life on publication and they can be discussed and torn apart. I had an idea, I assembled that, and also despite knowing very well what kind of response it will receive from many members in this forum, I put that on this forum....

    Now coming to you, why you are letting your paper languish at Vixra ?? Why not throw it open at least here for some discussions ? What are you afraid of ??

    And by the way what was your conclusion ??

    ............In summary, SM and thus GR, predicts its own downfall in much simpler, classical ways than e.g. seemingly perennial ‘singularity’ or ’black hole information paradox’ issues currently fashionable in quantum gravity circles...........

    You appear to be quite disdainful about GR and QGT ??
    Last edited: Apr 10, 2015
  9. RajeshTrivedi Valued Senior Member

    Brucep, ...You fancy some Quantum Foam at r = 0, which is self contradictory and extremely speculative...but you do not digest a simple pressure equilibrium, why ?

    Since you appear to know so much about GR, Quantum foam etc, why not do a simple exercise....find out the Gravitational Collapse Pressure as the function of (r) (for 2M<r<0) and show that NDP cannot counter it.....that is all is do not have to put forward Quantum Foam speculation at r = 0 to counter me.

    Do you understand, that if (Rs = size of our solar system), then the perceived density if the entire mass is uniformly distributed inside EH, is as good as that of air............So as I said if you start with a core of > 3.24 solar mass, then NDP will only be encountered inside EH, and please rebut, why it cannot counter gravitational pressure for the entire mass range...........
    Last edited: Apr 10, 2015
  10. RajeshTrivedi Valued Senior Member

    It appears that you have misunderstood the paper......I have not stated anywhere that a Neutron Star falls inside the BH..............

    Although this is not the part of my paper, but, here also I must correct you that we cannot meaningfully find out any spatial path of a falling object inside EH under SM.........

    [Although you have not stated path under SM, but it appears so, because of earlier post of Q-Reeus whom you took in quote]
  11. Q-reeus Valued Senior Member

    See my comments below.
    Which was quite brave no doubt given the savaging often dished out here at SF, but still was the right course. Like I wrote earlier, it can be very hard to cop criticism even if well meant. You seem from below to be reacting badly.
    That piece was way off-topic and meant I imagine to embarrass me somehow. Not really succeeding if so. I deliberately confined my critique of your proposed black NS to within what GR says - as your scenario assumed that regime ab initio. Simply a matter of being consistent with that. As far as my article, yes I have let it languish and have in fact had a further change of opinion recently (superseding my current comments below article summary) on a certain fairly important issue there. Given the need to juggle time and effort in any number of directions, including earning bread, fixing things that break, and prioritizing on more pressing topics that may get to print, it has taken a back seat.

    Getting back to this topic - black NS. Let's take a walk into imagination land. Where we can wave a magic wand and make our BNS infinitely strong and infinitely stiff - more infinitely than the infinite pressure it must endure. That immediately violates not only GR but SR because it implies infinitely fast wave velocity within the BNS media. But oh hell this is imagination land so no problems. But we won't make it totally free-for-all here in IL. We still have that SET (stress-energy tensor) applies as per GR:–energy_tensor
    Which means pressure is, 'all by itself', a source term - as in the principal (main diagonal) terms there. Which for a notionally static BNS boils down to rho + 3p, where rho is the proper energy density, and p the hydrostatic pressure. Now - recall that our BNS is under infinite pressure at all depths. Which in turn means, from SET, that the effective gravitational mass has blown out to infinite value! Hmm... 'just to be safe', let's wave that magic wand again and make our BNS infinitely infinitely infinitely strong and stiff - that's one more infinitely than the infinitely infinite pressure our BNS is enduring. That should do the trick, right?

    Wrong. Since pressure dominated effective mass and effective mass density is infinite, it follows that spacetime curvature becomes infinite - in particular for our case the spatial radial metric term goes to zero. So despite postulating infinite stiffness and strength, it still catastrophically collapses to zero radius owing to collapse of metric itself (as 'seen' from further out). Now there's snowballing with a vengeance! Sort of looks very much like a standard BH scenario has insisted on taking over, wouldn't you say?

    Maybe time to get back into the real world. Just a suggestion. If this seems overly sarcastic well just trying to really drive home how many ways your idea falls down by. No hard feelings my end. How about you Rajesh?
    [PS - the Black Star scenario of Visser et. al. is something that may appeal to you:
    evidently only quasi-stable and very speculative ]
    Last edited: Apr 10, 2015
  12. brucep Valued Senior Member

    I'm not referring to your goofball paper. I'm commenting on what would happen to your make believe black neutron star inside the event horizon. Specifically I was commenting on your complete lack of scholarship with respect to GR. Subsequently you should quit making erroneous comments about GR.
  13. RajeshTrivedi Valued Senior Member

    Your objection on both Nuclear Force count and having a specific path inside EH under SM is not sustainable.......throwing abusive language will not suffice.....I am sure you can do better without that.
    Last edited: Apr 10, 2015
  14. RajeshTrivedi Valued Senior Member

    Not to embarrass you, but to ask you a question...that why you are resorting to GR/SM to oppose my paper when you yourself have declared GR/SM dead in your that since you have fallen back on GR, then you are justified in taking a GR based stand.

    Since I have seen that paper of yours, irrespective of conclusion, your knowledge of maths around GR equations is quite demonstrative, I will certainly take your opinion and see further.....
    Last edited: Apr 10, 2015
  15. RajeshTrivedi Valued Senior Member

    Your this assertion is simply based on that coordinate singularity at r = 2M which appears in SM........Now the consensus is that there is no physically distinguishable disconnect at r = 2M, that means apparently there are no discontinuity in the spacetime at r = 2M, once there are no discontinuity it is a fallacy to consider infinite pressure at r = 2M- while having a measurable pressure at r= 2M+.... (from the perspective of a collapsing core from r > 2M)
    Last edited: Apr 10, 2015
  16. Q-reeus Valued Senior Member

    True there is nothing special happening at EH in terms of local physics i.e. curvature, but the prediction of infinite proper acceleration in order for any particle to hover there is not owing to a coordinate singularity. You'll need to go down around halfway to get the explicit derivation showing proper acceleration to hover at EH is infinite:
    Then simply apply the logic in post #29. Repeat - nothing to do with coordinate singularity. And the logic of #29 inevitably culminates in the scenarios of #48. With one relatively minor addition here - I neglected to account for redshifting of mass (as perceived from further out) fighting against the pressure amplification. Makes no important difference to the overall catastrophic collapse scene - a static BNS cannot be.
  17. RajeshTrivedi Valued Senior Member

    You are adding up many things again....around r = 2M

    .....Why don't we try to see from a different perspective.......

    1. What is the origin (formation process) of a SMBH ??

    a. Accretion (by a smaller BH)
    b. Direct from the core.

    If we talk of accretion than we need calculating the upper mass of a BH which can form due to gravitational collapse....but if we consider core collapse then the NDP scenario certainly pops up inside EH........(not suggesting that formation cannot involve accretion or direct or both.)
    Last edited: Apr 10, 2015
  18. Q-reeus Valued Senior Member

    I will take a stab and assume you are referring to the 'gossimer thin shell' of #29 as a collection of many point particles. So? Do you concede the argument and conclusion is sound? Do you further concede things only get more extreme in terms of curvature, hypothetical shell stresses etc. as one descends below EH? Assuming so, what's left to argue over?
    Assumed afaik to be both - starts with a massive or super-massive star stellar collapse (b) to BH, and accretion thereafter (a). Maybe there are scenarios where a collection of stellar mass BH's and/or normal stars in say a tightly packed globular cluster more or less collapse together as distinct from gradual accretion. Whatever.
    Not following your distinction which suggests accretion is onto a NS not SMBH. In which case one has the usual core collapse scenario as a result of accretion from e.g. companion star. Which is all getting away from the OP situation. Is there any further useful mileage here?
  19. paddoboy Valued Senior Member

    Not sure how you arrived at your calculations, but at this time I'll remain with the accepted GR maths as closer to reality.
    Pure speculation.
    No, that is not possible for many reasons.
    Having been absent for a few days I have just read through a few of the replies and your answers.
    As already mentioned you do at times appear to be going round in circles.
    A few points you still seem to deny are worth correcting again by me.
    [1] According to GR, once the Schwarzchild radius is reached, further collapse is compulsory.
    You seemed to have questioned that by claiming that therefor the "classical point Singularity" should be the result.
    Again my answer to that is that GR breaks down at the quantum/Planck level where our mass/Singularity will reside.
    I see it rather reasonable them to predict the Singularity being somewhere between the classical point singularity and the Planck/quantum level.
    This will then avoid the infinities involved with the point singularity, and establish a surface of sorts, where GR breaks down, and a QGT will reveal.

    [2]As we have argued about before, and as I have validated with reputable links, gravity can and does overcome all of the other forces, including the strong nuclear force at the Singularity/center of the BH is approached.

    [3] You have also in past threads denied the existence of BH's, which probably explains this paper and the use of a rather dodgy premise to get it published.

    [4]You are in effect throwing GR out, and like many papers that do the same,
    The methodology of using dodgy publishing companies, is needed to get this to be even noticed.

    In summing In the past, I have asked you many times for references re your claims. You have always countered with derision and scorn, claiming I should be "thinking for myself".
    Yet on a few occasions now, you have revealed that you yourself, have checked out links etc to confirm certain issues. Quite normal in actual fact, as no one including yourself, could ever write a paper, or make any solid claims without any references.
    In light of that, perhaps you can now reveal your sources for what you have claimed, and also links to refute what I have corrected you on.
    Afterall, that is what proper debate is all about.
  20. paddoboy Valued Senior Member

    But I have already done that in past threads, and you have written them off with unsupported scorn and derision.

    No, that is not how the theory is. Matter is totally broken down once it enters a BH, possibly even before it enters a BH to a certain extent. Electrons are stripped, atomic nuclei are torn apart by tidal gravity effects and even protons and neutrons are probably
    broken down further as the center is approached.
    All of these claims of mine have been referenced in past threads, and in most cases all those references and links are from reputable learning institutions.
    Perhaps now in light of your acceptance of reputable links, you can come up with some yourself to support your stance on this and other matters.

    GR may not depict gravity as a force per se. But the nature of the curvature of spacetime, does logically create "tidal gravity effects" This has literally the same effects as defined by a force

    A valid description of spacetime/gravity at the quantum/Planck level.

    Not according to GR.

    You have said that a couple of times now.
    Any way of looking at it is invalid if it does not conform with the tried and tested GR model of gravity.
    Last edited: Apr 10, 2015
  21. RajeshTrivedi Valued Senior Member

    Leave aside BNS for time being and see if you get through following...
    So, as far as you you know and let us say we know, an SMBH can form either through core collapse or accretion by a smaller BH....Now let us take the first part that is core please take an SMBH of one million solar mass, find out the EH and just think the density when the core is just of/at r = 2M (assuming uniform distribution first...which is not the truthful representation, but will lead us to something interesting)....and see of EDP or NDP has come by outside EH....a kind of precursor to BH.
    Last edited: Apr 11, 2015
  22. RajeshTrivedi Valued Senior Member

    Let us make a distinction between formation of BH through core collapse and life/misery of in falling matter into an already formed BH....

    This statement requires re adjustment on your part only Paddoboy, because it is intrinsically incorrect..

    1. Classical Singularity in GR is predicted at r = 0, not at Plancks' level. You have to see the equation to arrive at this conclusion, its been told to you by James R also.
    2. We are veering down to a consensus (not established) that Lp and Tp are the discrete lowermost quanta of length and if we go by this nothing can reside between Lp and r = 0 (classic singularity).
    3. If we think of entire mass at Planck's level, the density makes no sense, it goes to as high as 10^135 SI units even for a solar mass.......not a thing which scientists would trust so easily.

  23. paddoboy Valued Senior Member

    It appears you are continually making distinctions and seeing things other then the way they should be seen.
    An exercise in futility and against GR.

    No, it is correct and supported by my reputable links and references in past threads, as well as by at least one of tashja's Professors.
    The Singularity begins where GR breaks down or leaves off, and that is at the quantum/Planck level.

    I agree. The classical point singularity is certainly predicted at 0, and the reason why most physicists don't believe it goes that far. The infinite qualities involved are totally undesirable.
    I speak of the Singularity that by definition starts where GR leaves off.

    The Planck scale is a total theoretical mathematical basis obtained for convenience and represents a basic energy scale.
    At the Planck scale, the strength of gravity is expected to become comparable with the other forces, and it is theorized that all the fundamental forces are unified at that scale, but the exact mechanism of this unification remains unknown. The Planck scale is therefore the point where the effects of quantum gravity can no longer be ignored in other fundamental interactions, and where current calculations and approaches begin to break down, and a means to take account of its impact is required.
    This totally nullifies your suggestion that no quanta can exist below.
    It is also obviously the state of the mass that most physicists acceept while rejecting the total collapse to point singularity and those horrible infinite qualities of spacetime curvature and density that go with it.

    I'm not sure where you are getting your figures from, but I suggest that density at the Planck/quantum level, makes a heap more sense then the infinite density involved with the classical point scenario.
    Last edited: Apr 11, 2015

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