Free-fall to singularity is BS (or - don't just trust 'authorities')

Discussion in 'Alternative Theories' started by Q-reeus, Oct 23, 2014.

  1. RajeshTrivedi Valued Senior Member

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    This entire para is not coherent, why and how farsight commented this to be a great stuff is not clear..

    you say : Last part not true and in fact self-contradicted by later passage:




    There is no contradiction in above two statements, they are perfectly all right. If you read the subsequent posts of the original thread (beyond #495 from where you plucked this out)...then you will come to the conclusion yourself..
     
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  3. krash661 [MK6] transitioning scifi to reality Valued Senior Member

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    enough said.
     
    Last edited: Oct 25, 2014
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  5. paddoboy Valued Senior Member

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    My only motive is to let any youngins and lay people know, that what you speculate is just that...a speculative hypothesis, and will remain so until you undergo proper peer reveiw of your thoughts.
    At this time, GR stands as unchallenged by most mainstream cosmologists.
    And that is the point I'm making.
     
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  7. paddoboy Valued Senior Member

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    From the opening post:

    Add that also to the aggressive, provocative title of the thread....

    Free-fall to singularity is BS (or - don't just trust 'authorities')

    and its rather obvious you were itching for some sort of confrontation.
     
  8. Q-reeus Banned Valued Senior Member

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    Unfortunately however well meant, I find above too oblique to be of any real assistance. Anyway, to clean-up our correspondence, here's a late errata note concerning my #22:
    And later repeated in #31:
    A repeated slip-up, and should have in both cases referred to the second-last para:
    Sorry for any confusion caused. And really, that 'gedanken experiment' while useful is superfluous. The very fact of gravitational redshift is direct evidence objective yet at the same time relative clock slowing must be so. But the myth of 'it's just an optical illusion' re free-faller wrt outside observer is perpetuated by those who aught to perfectly well know better.
     
    Last edited: Oct 26, 2014
  9. Q-reeus Banned Valued Senior Member

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    Well how about you make it clear - instead of a vague assertion, flesh it out with actual detail. Which bits are 'incoherent' - and how exactly?
    Don't be so friggin lazy RT - you actually expect me to wade through all those subsequent mostly junk postings just to try and guess which one(s) are somehow relevant?! Point to precisely what you think are the relevant passage(s) in which posts. It is possible that owing to the ambiguity in that last quoted passage of Baez, he meant something different to how I interpreted it, But the onus is on you to 'prove' that. In either case, my subsequent argument is totally independent of any possible misconstruing there.
     
    Last edited: Oct 26, 2014
  10. Q-reeus Banned Valued Senior Member

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    Yes, cherry-picker hypocrite, but you conveniently left out (as I just noticed you also did back in #5) the all-important follow-on sentence:
    The title was accurate and frank - it was you from the start hurling aggressive and derogatory comments in a confrontational manner. And shown up to be a vacuous PC fanboy incapable of actually understanding what you so vehemently 'defend'. What's more relevant to my thread's banishment to this sub-forum, is the fact that by any objective criteria, I have never in any posting, been promoting an alternative theory! But having tried hard and failed repeatedly to entrap me with side-issues, I guess the realization came there was only one thing for it - just take the only option left. A naked act of censorship.

    That call for details of who why when in #35 has gone unanswered. What disrespectful, arrogant coward or cowards. But paddoboy, your final "It's done and dusted." remark in #33 gives a strong hint you were at least involved in pulling strings behind the scenes. Care to come clean? Who else do you know had a hand in it - paddoboy?
     
    Last edited: Oct 26, 2014
  11. paddoboy Valued Senior Member

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    Continued partial hidden threats, unsupported accusations and baseless assertions.
    My "done and dusted" remark was in relation to the settling of the contentious point in question. Even Farsight failed to agree with you.
    Your thread was moved. Live with it. You were putting forward another interpretation of GR.
    Again your remark "As some here are aware I reject GR anyway" says it all.
    I have no personal friends on this forum, moderators, or otherwise, and I am not in any position to pull any strings.
    That's just a childish "spitting the dummy" reaction over your thread being moved.
    I have also had at least three bannings in my time, and copped them all on the chin. And I think the accusations you are casting upon the moderation team, is similar to the accusations that a great number of Alternative theorists cast upon the mainstream science community and GR. In other words, nothing but a case of "sour grapes".

    I wait with baited breath to see what accusations and/or threats you will make next time you raise your head.
     
  12. Q-reeus Banned Valued Senior Member

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    I care nothing for the rest of your disingenuous rhetoric - but have no choice than to assume at least the above is truthful. Leave it at that then.
     
  13. RajeshTrivedi Valued Senior Member

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    Q-reeus,

    Let me attempt with some simple maths around Schwarzchild solution.. please advise if I am out of sync...

    1. Consider a frame at r1 = 1.000001 Rc from BH...and proper elapsed time in this frame T(F)
    2. Consider Earth at infinite distance from this BH and its proper time as T(E).

    For this set up......T(F) = T(E)/1000

    That means 1 year of T(F) shall be actually 1000 years of Earth. As r1 approaches Rc, this 1000 becomes a very large number, practically infinite. So the proper time on Earth is equal to the schwarzchild coordinate as referred in the para #2......this clears para #2

    Coming to para #1, it just says that if I am falling towards singularity then at EH, the t coordinate becomes infinite but its no body's proper time in local frame sense, nonetheless the time taken to fall to r = 0 is finite.

    The reference is to local sense only which was rightly clarified in the second para........So i see nothing wrong in these two paras..

    I will add one more thing here, the time taken to fall from EH to r = o is finite as clocked in fall guy clock and of the order of 2Rc/c..... This time will be seen from Earth as 2Rc/c only......but a frame at r1 = 1.000001Rc will clock only 2Rc/1000c........
     
  14. PhysBang Valued Senior Member

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    2,422
    Let me restate. The standard practice of physicists seems to be to treat the behavior of the Schwarzschild metric near the points of singularity as not representative of the physics of that region of spacetime. There are two reasons for this, as far as I can tell. One, because the behavior reflects mathematical peculiarities that other choices of coordinates do not have. Two, it is more practical to do physics that produces results and accepting the results from one specific system of coordinates in the face of contradictions is not practical. You, on the other hand, want to treat all of the Schwarzschild metric as exactly representing spacetime in all regions (excepting perhaps the points of singularity).

    Further to the above, I would submit that only in the face of a rival physical theory at least as good as GR is such a move justified. That is, if one were to criticize GR on the basis of this one peculiarity and offer a solution that avoids this peculiarity, one should only accept this solution if it offers, in general, the opportunity to do physics at least as well as GR.
     
  15. krash661 [MK6] transitioning scifi to reality Valued Senior Member

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    this is always the problem with these type of individuals.
     
  16. OnlyMe Valued Senior Member

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    Q-reeus, read slowly.., the Schwarzschild metric (SM) and Schwarzschild black holes (SBH) are simplifications of reality, that have no functional counterpart in reality. They are conceptual tools that make the theoretical exploration of some, but not all.., aspects of GR easier to model in an understandable manner.

    Before it makes any sense, to point to the flaws in the SM, as an example of reality and use that as an arguement against the validity of GR, point us to any observational evidence that a SBH, exists or can exist.

    If you step back and look at say the twin paradox, that arises within the context of special relativity, you have a similar situation. The conditions required by the twin paradox are unrealistic and likely may not even be possible under any circumstances... And yet they serve as a theoretical frame work, for a thought experiment that highlights some fundamental aspects of the underlying theory. The fact that it is likely impossible for anyone to reach the kinds of relativistic velocities, required by the SR twin paradox, does not invalidate the theoretical conclusions or the underlying theory, SR.

    The same is true for the SM and SBH. The fact that there is no evidence that either has any real world counterpart, does not lessen there conceptual value. It does counter your use of the inherent real world flaws, as an argument refuting GR. The SM is an imperfefect simplified theoretical exploration of real world conditions, that are far too complex to explore, within all of the real world conditions.

    Your argument is not much different than pointing out the flaws in the bowling ball and rubber sheet analogy and using that as an argument against the 4D theory, the analogy is drawn from.
     
  17. krash661 [MK6] transitioning scifi to reality Valued Senior Member

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    exactly like how you're incapable of actually understanding what you are criticizing huh.
     
  18. krash661 [MK6] transitioning scifi to reality Valued Senior Member

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    is this a " there's a conspiracy against my topic " nonsense ?

    Please Register or Log in to view the hidden image!

    comical.
     
  19. Q-reeus Banned Valued Senior Member

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    The single appropriate formula for above static situation relating relative clock-rates, for any two static (hovering) observers is that given in the lower right of Redshift Summary box here:
    https://en.wikipedia.org/wiki/Redshift#Redshift_formulae
    I will assume without checking your particular results above, they follow that formula (source = lower clock). And that is how I understood Baez there, so we seem to agree on that part.
    So far, so good. But understand it directly implies that all clocks located at *any* R > R_s (Schwarzschild radius, presumably your Rc) tick infinitely fast wrt clock at R = R_s (i.e. at EH). In other words, they age infinitely yet without one single tick of EH located clock (this wrongly assumes it's possible for such free-fall clock to have actually hit the EH in finite external time, but let's go with it here). And additionally, free-fall SR factor only makes the approach to that infinite temporal ratio happen more steeply than if working from that static redshift formula - just remove sqrt from acting on lower source term, and one has the free-fall ratio (outer clock hovering). [hasty edit: that's the objective ratio - the observed ratio needs that additional longitudinal SR Doppler factor I mentioned in #1]
    Yes it is. Again, ignore that free-fall from anywhere outside EH will take infinite exterior proper time (i.e. at any R > R_s) to reach EH. Then that t as *elapsed* proper time is infinite, for any external observer/clock, wrt proper elapsed time of EH located observer/clock. Infinite redshift = infinite clock-rate ratio. Rather basic, but the obvious consequence is amazingly just ignored or misrepresented as 'only apparent', an 'optical illusion'. Not true. As explained back in #1.
    If you totally ignore the external universe time is already, by above, already infinite just as EH is reached from outside free-fall. Alice-in-wonderland stuff is best confined to children's stories.
    But from which 'local sense'? I maintain Baez has contradicted himself, but regardless, the simple guts of my #1 - that the infinite redshift/clock-rate ratio is an objective thing. And it just kills the notion of free-fall from EH to 'singularity'. But as I said, some authorities, by innapropriate application of internal SM expression, find a magical situation where 'the clock starts ticking again' 'on the way down'. It makes zero physical sense, and similar to 'advanced solutions' in EM, one rejects such math on physical grounds. Or rather should.
    See above. Trouble is, folks just absorb what authorities say, assuming it must be right. Unlikely and bizarre as it may seem, they are necessarily wrong on this one. Oh, better add - imho.

    [I'm working here WAY over normal hours. Notice a new flurry of posts but - will answer (where that seems appropriate) much later. Bye bye for now now.]
     
    Last edited: Oct 26, 2014
  20. RajeshTrivedi Valued Senior Member

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    i have coloured some lines of your post in my quote..

    pardon me if I am wrong...but I could only figure out that you are mixing up the free fall invariance scenario, and you are also not appreciating the point that there cannot be any fixed FOR below EH in SM.
     
  21. paddoboy Valued Senior Member

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    From any local FoR, that is from the FoR of a person falling into a BH, time passes as per normal. There is no time dilation either outside the EH, or inside the EH.
    Time dilation is only observed from a remote FoR, observing said person falling into the BH....So much so, that the time is dilated to infinity, and the light is red shifted to infinity.
    So any exterior observer will never see anything cross the EH, just red shifted out of sight.
    Once one crosses the EH, one has no choice then to follow that very critical spacetime curvature and eventually hitting the Singularity in a finite amount of time, although once inside the EH, the role of space and time undergo a strange formation.
    The waterfall/fish swimming upstream analogy represents this pretty well.

    And of course one cannot chose any FoR to be more valid than any other. This is an indispensable principal of relativity. All FoR's are valid, and this appears what some seem to be forgetting.
    Just as I observing Alpha Centauri tonight, will actually see it as it was 4.25 years ago, while anyone near its vicinity, will see it as it is 4.25 years into my future.


    Or to put all that in a more professional way.......
    http://math.ucr.edu/home/baez/physics/Relativity/BlackHoles/fall_in.html
    "Won't it take forever for you to fall in? Won't it take forever for the black hole to even form?
    Not in any useful sense. The time I experience before I hit the event horizon, and even until I hit the singularity—the "proper time" calculated by using Schwarzschild's metric on my worldline—is finite. The same goes for the collapsing star; if I somehow stood on the surface of the star as it became a black hole, I would experience the star's demise in a finite time.

    On my worldline as I fall into the black hole, it turns out that the Schwarzschild coordinate called t goes to infinity when I go through the event horizon. That doesn't correspond to anyone's proper time, though; it's just a coordinate called t. In fact, inside the event horizon, t is actually a spatial direction, and the future corresponds instead to decreasing r. It's only outside the black hole that t even points in a direction of increasing time. In any case, this doesn't indicate that I take forever to fall in, since the proper time involved is actually finite.

    At large distances t does approach the proper time of someone who is at rest with respect to the black hole. But there isn't any non-arbitrary sense in which you can call t at smaller r values "the proper time of a distant observer," since in general relativity there is no coordinate-independent way to say that two distant events are happening "at the same time." The proper time of any observer is only defined locally.

    A more physical sense in which it might be said that things take forever to fall in is provided by looking at the paths of emerging light rays. The event horizon is what, in relativity parlance, is called a "lightlike surface"; light rays can remain there. For an ideal Schwarzschild hole (which I am considering in this paragraph) the horizon lasts forever, so the light can stay there without escaping. (If you wonder how this is reconciled with the fact that light has to travel at the constant speed c—well, the horizon is traveling at c! Relative speeds in GR are also only unambiguously defined locally, and if you're at the event horizon you are necessarily falling in; it comes at you at the speed of light.) Light beams aimed directly outward from just outside the horizon don't escape to large distances until late values of t. For someone at a large distance from the black hole and approximately at rest with respect to it, the coordinate t does correspond well to proper time.

    So if you, watching from a safe distance, attempt to witness my fall into the hole, you'll see me fall more and more slowly as the light delay increases. You'll never see me actually get to the event horizon. My watch, to you, will tick more and more slowly, but will never reach the time that I see as I fall into the black hole. Notice that this is really an optical effect caused by the paths of the light rays.

    This is also true for the dying star itself. If you attempt to witness the black hole's formation, you'll see the star collapse more and more slowly, never precisely reaching the Schwarzschild radius.

    Now, this led early on to an image of a black hole as a strange sort of suspended-animation object, a "frozen star" with immobilized falling debris and gedankenexperiment astronauts hanging above it in eternally slowing precipitation. This is, however, not what you'd see. The reason is that as things get closer to the event horizon, they also get dimmer. Light from them is redshifted and dimmed, and if one considers that light is actually made up of discrete photons, the time of escape of the last photon is actually finite, and not very large. So things would wink out as they got close, including the dying star, and the name "black hole" is justified.

    As an example, take the eight-solar-mass black hole I mentioned before. If you start timing from the moment the you see the object half a Schwarzschild radius away from the event horizon, the light will dim exponentially from that point on with a characteristic time of about 0.2 milliseconds, and the time of the last photon is about a hundredth of a second later. The times scale proportionally to the mass of the black hole. If I jump into a black hole, I don't remain visible for long.

    Also, if I jump in, I won't hit the surface of the "frozen star." It goes through the event horizon at another point in spacetime from where/when I do.

    (Some have pointed out that I really go through the event horizon a little earlier than a naive calculation would imply. The reason is that my addition to the black hole increases its mass, and therefore moves the event horizon out around me at finite Schwarzschild t coordinate. This really doesn't change the situation with regard to whether an external observer sees me go through, since the event horizon is still lightlike; light emitted at the event horizon or within it will never escape to large distances, and light emitted just outside it will take a long time to get to an observer, timed, say, from when the observer saw me pass the point half a Schwarzschild radius outside the hole.)

    All this is not to imply that the black hole can't also be used for temporal tricks much like the "twin paradox" mentioned elsewhere in this FAQ. Suppose that I don't fall into the black hole—instead, I stop and wait at a constant r value just outside the event horizon, burning tremendous amounts of rocket fuel and somehow withstanding the huge gravitational force that would result. If I then return home, I'll have aged less than you. In this case, general relativity can say something about the difference in proper time experienced by the two of us, because our ages can be compared locally at the start and end of the journey.
     
  22. brucep Valued Senior Member

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    The deep sickness is between your ears. Spewing nonsense in a science forum makes you an illiterate crank.
     
  23. paddoboy Valued Senior Member

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    Nothing stops, including time from ones local FoR, in this case from the FoR of someone approaching, falling in, and hitting the Singularity.


    Nice of you to add IMHO.
    On the rest of that paragraph......
    Sure, sometimes authorities and mainstream are wrong. Isn't this what science is all about, particularly the fields of Astronomy/Astrophysics and cosmology.
    Science moves closer and closer to reality as observations improve or discoveries are made.
    But in this instant, you seem to want to forgo the legitimacy of the realty of all FoR's.
    [see my previous post]
    Getting back to your authority comment again, and for the umpteenth time, if you have anything of any validity or value, we do have a scientific method and proper peer review systems.

    You also have made previous comments about by limited knowledge in this field, which I openly admit to, but this forum, over the last 6 months or so, have seen seen quite a number of "alternative hypothesis" regarding SR/GR, and at least four posters all claiming to have ToE's.
    A couple of these have been driven by Creationists/God Botherer agendas, others by "qualities" such as delusions of grandeur etc.
    All reasons for these claims have been as varied as the fact that all have been as adamant as you to their validity, and also all are vehemently critical of peer review.
    And yet you wish us to believe that in your case, the authorities are wrong?
     

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