Mainstream GR versus Farsight, mote in their eye or beam in his?

Discussion in 'Physics & Math' started by Farsight, Apr 25, 2016.

  1. paddoboy Valued Senior Member

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    I could say the same thing about you.

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    Yes, but not at "c"

    It's 1.5 Schwarzchild radius not 1.5 EH, and it isn't falling in at "c"at that orbit

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    Again it's 1.5 Schwarzchild radius for a Schwarzchild BH, and if you believe its bullshit, then why not write up a peer reviewed scientific paper and of rebuttal of Professor Hawking's paper?
    That would be the obvious thing to do. I'm sure though that you are in error in your assumptions and claims, and obviously whatever level of maths you have applied to come to such a astonishing conclusion.
    I'll certainly keep up with the news re any rebuttal of Professor Hamilton's paper.
     
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  3. paddoboy Valued Senior Member

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    'There is no issue other than in your mind, as has been the case with numerous other fabricated issues you seem to dream up every now and then.

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    Have you read the paper?
     
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  5. paddoboy Valued Senior Member

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    And you appear to be wrong on all counts. The first is the fact that this is an excellent analogy of spacetime within a BH's vicinity and the BH.
    The maths has been done is can be applied to most forms of BH's.

    http://arxiv.org/pdf/gr-qc/0411060v2.pdf
    This paper presents an under-appreciated way to conceptualize stationary black holes, which we call the river model. The river model is mathematically sound, yet simple enough that the basic picture can be understood by non-experts. In the river model, space itself flows like a river through a flat background, while objects move through the river according to the rules of special relativity. In a spherical black hole, the river of space falls into the black hole at the Newtonian escape velocity, hitting the speed of light at the horizon. Inside the horizon, the river flows inward faster than light, carrying everything with it. We show that the river model works also for rotating (Kerr-Newman) black holes, though with a surprising twist. As in the spherical case, the river of space can be regarded as moving through a flat background. However, the river does not spiral inward, as one might have anticipated, but rather falls inward with no azimuthal swirl at all. Instead, the river has at each point not only a velocity but also a rotation, or twist. That is, the river has a Lorentz structure, characterized by six numbers (velocity and rotation), not just three (velocity). As an object moves through the river, it changes its velocity and rotation in response to tidal changes in the velocity and twist of the river along its path. An explicit expression is given for the river field, a six-component bivector field that encodes the velocity and twist of the river at each point, and that encapsulates all the properties of a stationary rotating black hole.

    Summary:
    In this paper we have presented a way to conceptualize stationary black holes, which we call the river model. The river model offers a mental picture of black holes which is intuitively appealing, and whose basic elements are simple enough that they can be grasped by nonexperts. In the river model, space itself flows like a river through a flat background, while objects move through the river according to the rules of special relativity. For a Schwarzschild (non-rotating, uncharged) black hole, the river falls radially inward at the Newtonian escape velocity, hitting the speed of light at the horizon. Inside horizons, the river of space moves faster than light, carrying everything with it. We have presented the details that place the river model on a sound mathematical basis. We have shown that the river model works for any stationary black hole, rotating as well as non-rotating, charged as well as uncharged. The Doran35 coordinate system provides the coordinates of the flat background through which the river of space flows into the black hole. The extension of the river model to rotating black holes proves to be both surprising and pretty. Contrary to expectation, the river does not spiral into a rotating black hole: the azimuthal component of the river velocity is zero. Instead, the river has at each point not only a velocity, but also a rotation, or twist. The river is thus a Lorentz river, characterized by all six generators of the Lorentz group. As an object moves through the river of space, it is Lorentz boosted by changes in the velocity of the river along its path, and rotated by changes in the twist of the river. Equation (72) gives an explicit expression for the river field, a six-component bivector field that specifies the velocity and twist of the river at each point of the black hole geometry. The tidal boosts and twists experienced by an object in the river induce a curvature in the spacetime measured by the object, causing the metric to be non-flat. Changes in the river velocity rotate between space and time axes, while changes in the river twist rotate between two spatial axes. For a spherical black hole, the river has zero twist, so objects experience no spatial rotation, with the consequence that the metric, the Gullstrand-PainlevĀ“e metric, is flat along spatial hypersurfaces at constant time, dtff = 0. For a rotating black hole, the river has a finite twist, and the metric is not flat along spatial hypersurfaces.
     
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  7. Farsight

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    It's even simpler to explain why the universe was flat and homogeneous to begin with. And to point out that after nearly 40 years, there's still no evidence for inflation. Or that inventing it to explain why magnetic monopoles exist displays a woeful misunderstanding of electromagnetism. I'm sorry Schmelzer, but it isn't mainstream science, because it isn't science. And I'm not the only one saying that. Read this article: Physicist Slams Cosmic Theory He Helped Conceive
     
  8. The God Valued Senior Member

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    You got stuck with above response, simply because it is without copy pastes and links.

    So if spacetime is falling at c at EH, then it must be falling at some speed at 1.5 EH (not very difficult to calculate, if you understand escape velocity, total energy etc).....So if spacetime is falling at some non zero speed, how can you hold even a photon there ? This is pure BS, paddoboy. You got hooked to Prof Hamilton analogy...its easy to get hooked to such nonsense...mindless nonsense.
     
  9. The God Valued Senior Member

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    I am done with this river model, even Prof Hamilton may not be so obsessed with this as Paddoboy is...
     
  10. Farsight

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    Paddoboy, it's cargo-cult crap. We do not live in some Chicken-Little world where the sky is falling in. Space is not moving downwards in the room you're in. Instead it's homogeneous. And it isn't falling into a black hole either.
     
  11. Xelasnave.1947 Valued Senior Member

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    GR is a well tested model.
    What reality does it describe. Is it unreasonable to think of gravity as a flow of energy.
    Is it unreasonable to use an anology of a "river flow" or "a water fall" to visualise how GR seems to hint at reality.
    A field implies a flow of something rather than something static.
    I dont know enough about GR but doesnt the fact time and 3d is used point to describing a "flow" of space.
    Alex
     
  12. The God Valued Senior Member

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    No ifs and buts...You have good future here to become mainstream GR expert like your friend, just learn some copy paste stuff !! And start using language like my reputable links are better than yours....
     
  13. The God Valued Senior Member

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    3,546
    No ifs and buts...You have good future here to become mainstream GR expert like your friend, just learn some copy paste stuff !! And start using language like my reputable links are better than yours....
     
  14. Daecon Kiwi fruit Valued Senior Member

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    Yes, anything correct that you post (but The God doesn't like) is just you "parroting" stuff.
     
  15. paddoboy Valued Senior Member

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  16. paddoboy Valued Senior Member

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    27,543
    Why not ask Professor Hamilton and see what he says?
    My opinion is that the river/waterfall model is as I have already told you an analogy, and as you should know analogies do have limitations.
    From what I understand the analogy applies to BH's and the immediate vicinity.
    I might try and do you a favour and E-Mail the Professor to get his reply.
    But in the meantime after seeing you in action in the past and the many many fabricated scenarios you invent to try and invalidate some aspect of mainstream cosmology/GR, I'm sure this will also be a fizzer just as on all those occasions.

    In the meantime from the paper.....
    " We have presented the details that place the river model on a sound mathematical basis. We have shown that the river model works for any stationary black hole, rotating as well as non-rotating, charged as well as uncharged. The Doran35 coordinate system provides the coordinates of the flat background through which the river of space flows into the black hole"
     
  17. Xelasnave.1947 Valued Senior Member

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    8,502
    I would thank you for taking the time to help and guide me but I suspect you are being sarcastic.

    Forgive me if you are being genuine and if you are let me respond and say this.

    I do not want to become an expert. The proposition holds no interest.
    Besides I am too humble and very shy.

    Alex
     
  18. paddoboy Valued Senior Member

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    Havn't you used the same words before Farsight?
    Who do you believe you are impressing?
    And how's that TOE [theory of everything] you said you had?

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    Your credibility is zilch.
    I'll leave it at that chicken little.

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  19. paddoboy Valued Senior Member

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    The way of the crank, in the face of the outstanding advances in cosmology today is to write everything off as just "copy n pastes" or "pop science" or to fabricate unreal and nonsensical scenarios with regards to accepted cosmology.
    The real weird strange part about it all is that they themselves as unqualified and just lay people, seem to be under some form of illusion that anyone is taking any notice of them and that they seem to believe they are making some sort of difference to academia and the mainstream from a remote science forum such as this.......

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  20. paddoboy Valued Senior Member

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    You certainly believe in living in a fantasy world, don't you.
    we have his paper thus
    http://arxiv.org/pdf/gr-qc/0411060v2.pdf
    And his extended website at....
    http://casa.colorado.edu/~ajsh/home.html
    http://jila.colorado.edu/~ajsh/insidebh/index.html

    I'm sure we are all happy that you are done with it though, as obviously you fail to understand, [1] The paper, [2] the fact that its an analogy, and [3] the GR dynamics of BH's.

    If it still gets under your skin though, I'll keep an eye out for your rebuttal paper, oh and also Farsight's, although with the latter, I, the forum, the world, is still waiting for him to reveal his TOE he claimed to have formulated.

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    Last edited: May 4, 2016
  21. Farsight

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    They won't you know. In the Newtonian scenario the body dropped from an "infinite" distance is allegedly moving at the speed of light at the event horizon. It can't go faster than this.

    I disagree. The black hole forms from the inside out, like a hailstone. If you're a water molecule you can alight upon the surface but you can't pass through it. However you can be surrounded and buried by other water molecules, so the surface can pass through you.
     
  22. Farsight

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    3,492
    I understand them. You don't. But you will.

    No you haven't, you made claims that don't hold water. Einstein said space, and he meant space. Don't change it into something it isn't. We describe the state of space using light, moving. When it's moving macroscopically in the x y z directions we refer to these as our spatial coordinates. When it's moving back and forth locally inside our optical clock we refer to the count of reflections t as our time coordinate. We establish the state of space using light moving through it. For example we place optical clocks through an equatorial slice through the Earth and the surrounding space.

    Phooey. You're trying to rewrite Einstein's words to fit your own misunderstanding. Space is not spacetime. There is no motion in spacetime, it models an all-times block universe which is utterly static, and the map is not the territory. Space and light moving through it is the territory. And you know full well that the t coordinate has the opposite sign: see Einstein's derivation of the Lorentz transformation here.

    No. You are getting this totally wrong because you're clinging to misunderstanding. Einstein didn't even use the word curvature in his Leyden Address. Read what he actually said: "'empty space' in its physical relation is neither homogeneous nor isotropic, compelling us to describe its state by ten functions (the gravitation potentials \(g_{\mu\nu}\)) ". A gravitational field is a place where the potentials are not uniform. It's the first derivative of potential. Tidal force occurs where the gravitational field is not uniform, where there's a curvature rather than just a slope in the potential. It's the second derivative of potential. Space is inhomogeneous or not uniform where a gravitational field is. Further to this the inhomogeneity is in itself not uniform in that it reduces with distance from the star. When you plot it using optical clocks in that equatorial slice, you see the curvature which is known as curved spacetime :

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    You're getting it back to front. Because of the concentration of energy, space is inhomogeneous, therefore the gravitational potential is not uniform, therefore we have a gravitational field. And because the effect diminishes with distance the inhomogeneity reduces so the gradient in potential aka gravitational field reduces and we have the spacetime curvature and a tidal force. As I've said before this spacetime curvature is the "defining feature" of a gravitational field, because without it your plot is stays flat and level, and there is no gravitational field. But it's the spatial inhomogeneity in the room you're in that makes your pencil fall down. Not some curvature of spacetime in that room.
     
  23. Schmelzer Valued Senior Member

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    Yes, to "point out", making claims without any argument supporting them, is, indeed simple. You are not the first here in this forum who likes this.

    That the universe was flat and homogeneous at the beginning is, of course, a cheap assumption. Not really an explanation, it simply assumes instead of deriving. But, of course, homogeneous initial conditions and zero curvature are the simplest initial conditions, thus, preferable by Occam's razor.

    Unfortunately, this does not explain the size of the inhomogeneities. They are much too large to be explainable without inflation.

    I have almost completely rewritten http://ilja-schmelzer.de/gravity/inflation.php and recommend to take a look at it.

    But, wait, the evidence is only for a very particular property of inflation: That there was, in the early universe, a period of time where the expansion rate was increasing. Which would have better named "accelerated expansion", as I explain. It does not give any support to any of the proposed mechanisms for inflation. The mechanisms, which are able to lead to such an effect of an increasing expansion rate, are completely speculative.

    Monopoles are, of course, also completely speculative. (AFAIR you have the story wrong. There were some speculative theories which would have created a lot of monopoles, so many of them that they should have been already observable. And then inflation was used to explain that we nonetheless cannot see them, to save these speculative theories with monopoles from falsification. But all this IIRC, I have never cared much about this.)

    I fully agree with Steinhardt's position. The only difference is that he uses the word "inflation" in a more restricted way, naming only all these speculative particle theories "inflation":

    But what is a "big bounce"? It is a period of time where the universe was, first, shrinking. Then, shrinking stops, a minimum is reached, and then expansion starts. All this, I would hope, quite smooth, so that the curve near the big bounce would be similar to an U, or to $a(\tau) \sim a_0 + \tau^2$ or so. Thus, this would be a period with increasing expansion rate, starting from a negative expansion rate. So, it would be also a particular example of what I have named above, and on my website, inflation. But this is only a difference in the use of the word "inflation".
     

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