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Murad's misunderstanding of Einstein's GR

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  • JACK SARFATTI
    No, you are garbling two definitions of gravitational field . In simplest case in GR for static LNIF detectors, for a static, spherically symmetric source
    Message 1 of 3 , Apr 1, 2010
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      No, you are garbling two definitions of "gravitational field".

      In simplest case in GR for static LNIF detectors, for a static, spherically symmetric source outside its event horizon (assuming it's a black hole)

      g00 = 1 + 2VNewton/c^2) = - 1/grr

      The gravitational field Einstein means in his "equivalence principle" is not the curvature at all. It is the same g-force (per unit test mass) every fighter pilot is familiar with.

      g = - dVNewton/dr

      VNewton = - GM/r

      The curvature is the variation of the g-force, i.e. second order partial derivatives of VNewton.

      What Zielinski means by a uniform gravity field is

      VNewton = gz 

      Obviously, the second order partial derivatives vanish, therefore the curvature tensor is zero.

      Although, the curvature tensor is the covariant curl of the connection, since the connection is zero in LIFs, the curvature tensor really is zero under these conditions.




      On Apr 1, 2010, at 6:30 AM, Paul Murad wrote:

      Guys:
       
      Look at what you are really saying.  For a uniform gravitational field, you are saying that the curvature of the space-time continuum is none zero and is a constant.  How long can that go on?
       
      Thus it is reasonable to say that you are only looking at a portion of the space-time continuum where the curvature is constant and the space is within a specific domain so that you do not have to treat large gradients or edge effects.
       
      I think that would be entirely reasonable.
      Ufoguy....


      From: Paul Zielinski <iksnileiz@...>
      To: JACK SARFATTI <sarfatti@...>
      Cc: Paul Murad <ufoguypaul@...>; Sarfatti_Physics_Seminars <Sarfatti_Physics_Seminars@yahoogroups.com>; "SarfattiScienceSeminars@YahooGroups. com" <SarfattiScienceSeminars@yahoogroups.com>; David Gladstone <d14947@...>; nick herbert <quanta@...>; S-P Sirag <sirag@...>; COLIN BENNET <sharkley1@...>; Mark Pesses Pesses <MPOGO@...>; David Kaiser <dikaiser@...>; Sharon Weinberger <sharonweinberger@...>; Gary Bekkum <garybekkum@...>; James Woodward <jfwoodward@...>; David McMahon <dmmcmah@...>; Creon Levit <creon.levit@...>; Hal Puthoff <Puthoff@...>; Waldyr A. Rodrigues Jr. <walrod@...>; R Kiehn <rkiehn2352@...>; Carlos Castro <czarlosromanov@...>; Dave Williams <djw0305@...>; Robert Becker <roberte.becker@...>; Геннадий Шипов <warpdrive09@...>; Eric Krieg Krieg <eric@...>; Eric Davis <tachyondavis@...>; "antigray ," <ANTIGRAY@...>
      Sent: Thu, April 1, 2010 2:20:29 AM
      Subject: Re: Zielinski's misreading of Einstein's actual text "homogeneous in the first approximation"

      Jack, I believe you've just scored yet another of your world famous "own goals" here.

      When he refers to a "homogeneous" gravitational field, Einstein is not talking about a uniform frame acceleration field.
      He is talking about an *actual* gravity field of uniform field strength. 

      There is no problem with defining such a field operationally, since test object acceleration can always be measured at 
      every point at *zero test object velocity*, eliminating any SR-related effects. 

      So what Einstein has in mind here when he uses the term "homogeneous to first order" is the non-vanishing curvature 
      associated with typical gravity fields produced by matter.

      Now it is nevertheless true that a RIndler frame (relativistic accelerating frame of reference) does exhibit such SR-type 
      effects -- but this is just another argument against Einstein's proposed principle, since it ensures that the phenomena observed 
      in such a frame differ from those observed from a non-accelerating frame even in the presence of a perfectly homogeneous 
      gravity field (Einstein's best case).

      So yes Einstein was later forced to retreat even from this version of the principle, even given his best case of a perfectly 
      homogeneous ("certain kind of") gravity field compared with a uniform acceleration field, eventually restricting the principle to what 
      we like to call "local" observations, irrespective of the question of spacetime curvature.

      You don't seem to realize that this is an argument *against* Einstein's original concept of equivalence, not for it.

      In any case, even if one is restricted to pure local observations, the principle as stated still does not work. Why? Because you 
      cannot 
      recover non-tidal gravitational acceleration -- a locally observable phenomenon -- from *any* kind of frame acceleration, 
      either
       globally or locally!

      You can always bring a test object as close as you like to a source boundary, and locally measure its acceleration with respect
      to the source. Such locally observable gravitational acceleration will not be observed in *any* kind of frame acceleration field. Which
      means that Einstein's proposed principle as stated is simply false: the laws observed even in a perfectly homogeneous gravity
      field are not the same as those observed in a homogeneous gravitational field -- not even approximately.

      Vilenkin's vacuum domain wall solutions, in which the vacuum geometry is completely Riemann flat,  show that this kind of situation 
      does exist in 1916 GR. A test object released near such a gravitational source will experience locally observable gravitational 
      acceleration with respect to the source, which will not be observed in *any* pure frame acceleration field with the gravitational source 
      switched off (by which I mean a Rindler frame in a Minkowski spacetime -- a pure frame acceleration field). 

      So the only way to get Einstein's principle as stated to work is to ignore the phenomenon of gravitational acceleration. But what kind of a
      "theory of gravity" can be based on such a principle?

      My answer here is simple: Einstein's version of the equivalence principle is simply not supported by his 1916 theory of gravity. It is
      simply a figment of Einstein's fevered imagination.

      Which is what I've been saying all along.

      Z.


      On Wed, Mar 31, 2010 at 6:41 PM, JACK SARFATTI <sarfatti@...> wrote:

      As I have been trying to explain to Zielinski without success is that such a global uniform gravity field does not exist because of special relativity time dilation and length contraction - I mean it does not exist in same sense that it would in Newton's gravity theory using only the v/c ---> 0 Galilean group limit of the Lorentz subgroup of the Poincare group. Einstein was perfectly aware of this in the quote Zielinski cites - Zielinski simply does not understand Einstein's text in my opinion.

       
      On Mar 31, 2010, at 6:23 PM, Paul Murad wrote:

      A "paradoxical" property

      Note that Rindler observers with smaller constant x coordinate are accelerating harder to keep up! This may seem surprising because in Newtonian physics, observers who maintain constant relative distance must share thesame acceleration. But in relativistic physics, we see that the trailing endpoint of a rod which is accelerated by some external force (parallel to its symmetry axis) must accelerate a bit harder than the leading endpoint, or else it must ultimately break. This is a manifestation of Lorentz contraction. As the rod accelerates its velocity increases and its length decreases. Since it is getting shorter, the back end must accelerate harder than the front. This leads to a differential equation showing, that at some distance, the acceleration of the trailing end diverges, resulting in the #The Rindler horizon.
      This phenomenon is the basis of a well known "paradox". However, it is a simple consequence of relativistic kinematics. One way to see this is to observe that the magnitude of the acceleration vector is just the path curvature of the corresponding world line. But the world lines of our Rindler observers are the analogs of a family of concentric circles in the Euclidean plane, so we are simply dealing with the Lorentzian analog of a fact familiar to speed skaters: in a family of concentric circles, inner circles must bend faster (per unit arc length) than the outer ones.
      Paul:

      Okay. I just want to make sure we are on the same sheet of music...
      Ufoguy...


      From: Paul Zielinski <iksnileiz@...>
      To: Paul Murad <ufoguypaul@...>

      Sent: Wed, March 31, 2010 8:56:03 PM
      Subject: Re: Zielinski's misreading of Einstein's actual text

      In this context "homogeneous" simply means that the gravitational field strength is uniform at all 
      points in some region of space.  

      I suppose what we really mean here is a *static* homogeneous gravitational field, which doesn't
      vary in time.

      On Wed, Mar 31, 2010 at 5:42 AM, Paul Murad <ufoguypaul@...> wrote:
      Paul:
       
      When you say locally homogeneous, to me that does not mean homogeneous at all but can represent a large multi-connected region that consists of elements that are inhomogenous.
      To me homogeneous means going on forever and having the same consistency.  If I was building a propulsor that involved controlling gravity, it would from a distance represent a singularity within a homogeneous field.
      Ufoguy...


      From: Paul Zielinski <iksnileiz@...>
      To: Paul Murad <ufoguypaul@...>

      Sent: Tue, March 30, 2010 7:04:02 PM

      Subject: Re: Zielinski's misreading of Einstein's actual text

      Actually it's the other way around -- an accelerating frame produces the Einstein equivalent of a perfectly
      homogeneous gravitational field.

      For the purposes of my current objection to Einstein's principle the field only has to be *locally* homogeneous, 
      since a test particle experiences gravitational acceleration with respect to a source if and only if the first coordinate-
      covariant derivatives g_uv: w of the metric are locally non-zero. In a flat spacetime, the first coordinate-covariant derivatives
      of the metric are all zero, although the non-covariant partial derivatives g_uv, w of the metric are not all zero in accelerating 
      frames. 

      So the technical details about what kind of source is required to produce a locally homogeneous field are
      not really important here. If you're interested in this, however, Vilenkin has published papers on a vacuum domain 
      wall that according to the GR fielld equations acts as the source of a flat field everywhere outside the wall. 

      Of course the field produced by a "planet" -- like any other spherically symmetric source in GR -- is not at all homogeneous. 


      On Tue, Mar 30, 2010 at 5:40 AM, Paul Murad <ufoguypaul@...> wrote:
      Paul:
       
      I have to assume that your use of homogeneous gravitational field implies one created by a planet while one could argue that an inhomogeneous gravitational field would be one derived from a propulsion system.  Is that correct?
      Paul...


      From: Paul Zielinski <iksnileiz@...>
      To: JACK SARFATTI <sarfatti@...>

      Sent: Tue, March 30, 2010 5:15:27 AM
      Subject: Re: Zielinski's misreading of Einstein's actual text

      I guess you missed the point that even if the gravity field is perfectly homogeneous and the frame acceleration
      field is completely uniform, and the observations are entirely "local", Einstein's version of EP still doesn't work,
      since you cannot get locally observable gravitational acceleration from *any* kind of frame acceleration.

      In any case there is nothing in Einstein's 1916 definition of "equivalence" that refers to locality. He claims that the laws 
      satisfied by a homogeneous gravity field are exactly the same as those satisfied by a uniform frame acceleration
      field. Which is simply false, as I've explained, even if all observations are kept strictly "local".

      If the gravity field is homogeneous, then there is no question of "first approximation" -- the equivalence would have
      to be exact. 

      JACK SARFATTI wrote:
      In fact Paul you simply have made an elementary error in reading the text you blanked out at

      "(homogeneous in the first approximation)"

      this clearly means local frame - not global frame 


      On Mar 29, 2010, at 11:47 PM, Paul Zielinski wrote:

      JACK SARFATTI wrote:
      You are mis-reading the text Paul. In many other places Einstein makes clear he does not mean this globally, only locally.
      Later -- under heavy criticism -- Einstein did modify this categorical version of the principle. But the original version states clearly that 
      with respect to the known laws of physics at least a globally homogeneous ("a certain kind of") gravitational field can "in all 
      strictness" be substituted for a frame acceleration field without *any* of the known laws of physics being violated.


      the equivalence principle has two facets

      1) Newton's gravity force is eliminated at the COM of an LNIF

      2) Newton's gravity force is the inertial force in a very special STATIC LNIF

      end of story

      PS Einstein never used "globally homogeneous" that's false.

      On Mar 30, 2010, at 12:00 AM, Paul Zielinski wrote:

      Jack, however you want to slice and dice this, even t'Hooft writes that Einstein misunderstood GR in the
      early days. t'Hooft clearly doesn't buy into Einstein's original version of EP either!

      Einstein clearly understood that his frames K & K' are local frames.

      Also there is no such thing even in special relativity as a uniform gravity field extending over all space! Look at the Rindler problem!

      A "paradoxical" property

      Note that Rindler observers with smaller constant x coordinate are accelerating harder to keep up! This may seem surprising because in Newtonian physics, observers who maintain constant relative distance must share thesame acceleration. But in relativistic physics, we see that the trailing endpoint of a rod which is accelerated by some external force (parallel to its symmetry axis) must accelerate a bit harder than the leading endpoint, or else it must ultimately break. This is a manifestation of Lorentz contraction. As the rod accelerates its velocity increases and its length decreases. Since it is getting shorter, the back end must accelerate harder than the front. This leads to a differential equation showing, that at some distance, the acceleration of the trailing end diverges, resulting in the #The Rindler horizon.
      This phenomenon is the basis of a well known "paradox". However, it is a simple consequence of relativistic kinematics. One way to see this is to observe that the magnitude of the acceleration vector is just the path curvature of the corresponding world line. But the world lines of our Rindler observers are the analogs of a family of concentric circles in the Euclidean plane, so we are simply dealing with the Lorentzian analog of a fact familiar to speed skaters: in a family of concentric circles, inner circles must bend faster (per unit arc length) than the outer ones.



      How is that different from Fock's observation that "Einstein didn't understand his own theory" (of gravity)?

      Forck was under Stalin's thumb - it was simple politics. He did not want to go to the Gulag like Landau. It's as if the US was run by Scientology!

      What t'Hooft does not acknowledge in his diatribe is that the modern "infinitesimal" version of EP does
      not support Einstein's concept of "general relativity".

      Paul that's silly nonsense in my opinion.

      That is the point at issue here.

      If you would just open your eyes it should be obvious that Einstein's classic version of the principle is simply
      not supported by actual known gravitational physics. Known laws of gravity physics are in fact violated -- 
      even locally -- when you substitute a homogeneous actual gravitational field for a frame acceleration field.

      Nonsense - this is Einstein's conception right here

      <Mail Attachment.jpeg>


      This is what is commonly meant in foundations of physics when it is said that from a contemporary 
      perspective the status of Einstein's general relativity concept is to be regarded as *purely heuristic*.

      Who cares? So what? It has no importance for any significant problem. All physics is purely heuristic. What else is new?
      Physics is not the same as mathematics. Physics uses mathematics, but there is nothing in physics that can be proved like a mathematical theorem is proved. 

      "As far as the laws of mathematics refer to reality, they are not certain, as far as they are certain, they do not refer to reality."

      If you are out to describe the truth, leave elegance to the tailor.
      Albert Einstein


      JACK SARFATTI wrote:

      On Mar 29, 2010, at 10:52 PM, Paul Zielinski wrote:

      So, is this what t'Hooft had in mind when he wrote,

      "They find some support from ancient publications by famous physicists; in the first decades of 
      the 20th century, indeed, Karl Schwarzschild, Hermann Weyl, and even Albert Einstein, had 
      misconceptions about the theory, which at that time was brand new, and these pioneers indeed 
      had not yet grasped the full implications. They can be excused for that, but today's professional 
      scientists know better
      ."

      Ironically, in the above t'Hooft appears to agree with my position that Einstein's original version
      of the EP (below) is not in fact supported by the modern version of GR.

      You see things in a very distorted way - way out of balance. On your particular point I have seen Einstein write explicitly he meant in the small!
      You are caught in a very trite quibble of no importance - in my opinion.

      Which has been my position all along. What t'Hooft doesn't explicitly acknowledge here is 
      that among Einstein's "misconceptions" about his 1916 theory of gravity was his entire concept 
      of what he called "general relativity"!

      The critical point here is that the modern version of EP, unlike Einstein's classic version below, is 
      not a generalized relativity principle. It is merely a GR <-> SR correspondence principle, which is 
      only strictly valid (and need only be strictly valid) inside an infinitesimal spacetime region, and
      even then only with respect to a restricted subclass of "local" measurements.

      The onus, the burden of proof is on you to prove that your imagined difference here makes a significant difference to the foundations of physics. I think not. Prove me wrong.


      Paul Zielinski wrote:
      FYI, here is Einstein's clearest public statement of *his* version of the equivalence principle:



      Note the sentence "The assumption that one may treat K' as at rest in all strictness 
      without any laws of nature not being fulfilled with respect to K', I call the 'principle of 
      equivalence'
      ." 

      This is Einstein 1916, after publication of his 1916 theory of gravity. Straight from the
      horse's pen. This is the theoretical basis for Einstein's generalized relativity principle.

      There is no limitation to infinitesimal regions of spacetime in this version of the equivalence 
      principle. The physical identification of a uniform frame acceleration
       field with a globally 
      homogeneous gravity field is *categorical* with respect to the "known laws of physics".

      I am not saying (unlike Einstein himself) that such a principle is actually supported by 1916 
      GR. In fact I'm saying the opposite.

      Evidently you agree with me on this, and not with Einstein.

      Paul Zielinski wrote:


      On Mon, Mar 29, 2010 at 12:18 AM, JACK SARFATTI <sarfatti@...> wrote:
      there is no such thing as a global relativity principle in GR

      There is no such thing as a global equivalence principle in GR -- which means that there
      is no such thing as "general relativity", as originally conceived by Einstein, in 1916 GR.

      Einstein's original concept of "general relativity" was based on a globally valid generalized
      relativity principle. But it turns out that such a principle is *not supported* by 1916 GR. 

      Which is exactly what V. Fock argued in his book, "The Theory of Space Time and 
      Gravitation"
      , saying that "general relativity" was a misnomer.

      So after all you really agree with me on this. You just won't admit it.
       

      On Mar 28, 2010, at 9:27 PM, Paul Zielinski wrote:



      On Sun, Mar 28, 2010 at 5:03 PM, JACK SARFATTI <sarfatti@...> wrote:

      On Mar 28, 2010, at 4:08 PM, Paul Zielinski wrote:

      t'Hooft seems to believe that there is no difference between a generalized relativity principle and a mere
      correspondence principle. If that's what he thinks, then he's just wrong. 

      Frankly I don't understand your distinction and neither obviously does 't Hooft.

      In that case neither of you understands Einstein. The fact of the matter here is that Einstein's equivalence 
      principle was global, not local -- as it must be to serve as a generalized relativity principle.'

      Hogwash - in fact ridiculous - 't Hooft has a Nobel and deserved it.

      I have no doubt. 

      Your assertion that Einstein's principle was never intended to be global is just false. 
       
      Suppose you turned out to be correct, so what?

      It changes our understanding of the physical meaning of GR, and may resolve difficulties reconciling GR
      with quantum gravity (including condensate theories).

      Hogwash - prove it with examples.

       
      What significant difference would it make?

      What immediate difference does Bohm's alternative interpretation of quantum mechanics make? 

      quite a bit - shown by Valentini

       
      In any case until you clearly explain what you mean precisely in the above jargon you are simply not communicating clearly.

      I think you understand the difference between a global relativity principle and a local correspondence principle.

      For one thing, a global relativity principle must hold for *all* observations, not just a restricted class of "local"
      measurements. 


      Of course I agree that the various stress-energy pseudotensors labeled "t_uv" are features of linearized
      GR, and as such do actually arise in GR from the non-linearity of the field equations. However, this does not 
      conflict with proposals like Yilmaz', for example, in which the field equations are linear and the solutions 
      are thus additive.

      Why only linearized? It's there in strong field also.

      In GR the stress-energy pseudotensors t_uv are artifacts of linearization. That's what t'Hooft himself says. There is
      no need for them in the exact solutions of the actual field equations.

      The real question is here is, can the non-linearity contribution to the GR vacuum  stress-energy be represented
      by a tensor quantity? I say yes it can, precisely because the GR field equations are fully covariant. And this has
      nothing to do with the modern version of EP.

      Prove it.


      My point here is that this should not be confused with the question of non-linearity of the field equations. 


      So t'Hooft is mixing up the issue of non-linearity of the GR field equations with the question of the localization
      and tensor character of the vacuum stress energy. These are all distinct issues. 

      On Sun, Mar 28, 2010 at 2:07 PM, JACK SARFATTI <sarfatti@...> wrote:
      Read the complete article by 't Hooft at http://www.phys.uu.nl/~thooft/gravitating_misconceptions.html

      excerpts - my comments in [ ... ] unless I say to the contrary, I agree with the quoted excerpts. I want it to be clear that I am a "radical conservative" in John Archibald Wheeler's sense. I think mainstream quantum theory and relativity are correct. All physical theories have limited domains of validity in David Bohm's sense, but all extensions of mainstream physics theories must limit to them, e.g. Antony Valentini's post-quantum theory with "signal nonlocality" violating "no-cloning" "passion at a distance" (A. Shimony) in sub-quantal non-equilibrium of the particle trajectories and classical field configuration "hidden variables" http://eprintweb.org/S/authors/All/va/Valentini

      As should be clear from my past discussions with Z, I definitely agree with 't Hooft's:

      "These self proclaimed scientists in turn blame me of "not understanding functional analysis". Indeed, L maintains that there is a difference between a  mathematical calculation and its physical interpretation, which I do not understand. He makes a big point about Einstein's "equivalence principle" being different from the "correspondence principle", and everyone, like me, who says that they in essence amount to being the same thing, if you want physical reality to be described by mathematical models, doesn't understand a thing or two. True. Nonsensical statements I often do not understand. What I do understand is that both ways of phrasing this principle require that one focuses on infinitesimally tiny space-time volume elements."

      &

      "I emphasize that any modification of Einstein's equations into something like  R μν  - 1/2 R gμν κ(Tμν + t μν (grav))   where  t μν (grav)   would be something like a "gravitational contribution" to the stress-energy-momentum tensor, is blatantly wrong.   Writing such a proposal betrays a complete misunderstanding of what General Relativity is about. The energy and momentum of the gravitational field is completely taken into account by the non-linear parts of the original equation. This can be understood and proven easily, as I explained in the main text.  Note that a freely falling observer experiences no gravitational field and no energy-momentum transfer; hence there cannot be a covariant tensor such as  t μν (grav) ."
    • JACK SARFATTI
      Paul You misunderstood what I meant in the last part. We are not in disagreement on the last point. Formally the curvature tensor is local. I meant, given that
      Message 2 of 3 , Apr 2, 2010
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        Paul
        You misunderstood what I meant in the last part. We are not in disagreement on the last point. Formally the curvature tensor is local.

        I meant, given that the curvature tensor is (non)zero in the  LNIF it will still be (non)zero in the coincident LIF.

        7d4790b7c01032ab404e9f95a9ebf976.png

        this is a set of local functions, whose vanishing or non-vanishing is local frame independent.

        The last two terms on RHS always vanish in a LIF, but if the first two terms do not vanish in the LNIF they also will not vanish in the coincident LIF.

        However, the relative tidal accelerations between a pair of free-float zero g-force test particles can be made arbitrarily small - up to 

        &L = (LP^2L)^1/3 = hologram fuzziness in 3D < L is the UV limit

        where the momentum transfer in a scattering measurement is ~ h/L

        where L << radii of curvature R is the IR limit.

        i.e. the momentum transfer pass band is

        h/R < h/L < h/&L


        On Apr 1, 2010, at 8:32 PM, Paul Zielinski wrote:

        I agree with everything Jack says below, except the last part.

        On Thu, Apr 1, 2010 at 11:24 AM, JACK SARFATTI <sarfatti@...> wrote:
        No, you are garbling two definitions of "gravitational field".

        In simplest case in GR for static LNIF detectors, for a static, spherically symmetric source outside its event horizon (assuming it's a black hole)

        g00 = 1 + 2VNewton/c^2) = - 1/grr

        OK.

        The gravitational field Einstein means in his "equivalence principle" is not the curvature at all. It is the same g-force (per unit test mass) every fighter pilot is familiar with.

        g = - dVNewton/dr

        VNewton = - GM/r

        OK.

        The curvature is the variation of the g-force, i.e. second order partial derivatives of VNewton.

        It is a covariant measure of the differential variation of the g-force along the spacetime manifold.

        What Zielinski means by a uniform gravity field is

        VNewton = gz 

        Right. Which is exactly what Einstein meant.

        Obviously, the second order partial derivatives vanish, therefore the curvature tensor is zero.

        OK.

        Although, the curvature tensor is the covariant curl of the connection, since the connection is zero in LIFs, the curvature tensor really is zero under these conditions.

        Bzzzzt! Not OK!

        Jack you know very well that if the Riemann tensor R^u_vwl(x) does not vanish at some spacetime point x in any given CS,
        then it is not zero at x in every other. So clearly this cannot be true: no coordinate transformation from an LNIF to an
        LIF can
        zero out the Riemann curvature tensor.

        R^u_vwl(
        x) =/= 0 unless R^u'_v'w'l'(x) = 0 in every other frame.

        Z.




        On Apr 1, 2010, at 6:30 AM, Paul Murad wrote:

        Guys:
         
        Look at what you are really saying.  For a uniform gravitational field, you are saying that the curvature of the space-time continuum is none zero and is a constant.  How long can that go on?
         
        Thus it is reasonable to say that you are only looking at a portion of the space-time continuum where the curvature is constant and the space is within a specific domain so that you do not have to treat large gradients or edge effects.
         
        I think that would be entirely reasonable.
        Ufoguy....


        From: Paul Zielinski <iksnileiz@...>
        To: JACK SARFATTI <sarfatti@...>
        Cc: Paul Murad <ufoguypaul@...>; Sarfatti_Physics_Seminars <Sarfatti_Physics_Seminars@yahoogroups.com>; "SarfattiScienceSeminars@YahooGroups. com" <SarfattiScienceSeminars@yahoogroups.com>; David Gladstone <d14947@...>; nick herbert <quanta@...>; S-P Sirag <sirag@...>; COLIN BENNET <sharkley1@...>; Mark Pesses Pesses <MPOGO@...>; David Kaiser <dikaiser@...>; Sharon Weinberger <sharonweinberger@...>; Gary Bekkum <garybekkum@...>; James Woodward <jfwoodward@...>; David McMahon <dmmcmah@...>; Creon Levit <creon.levit@...>; Hal Puthoff <Puthoff@...>; Waldyr A. Rodrigues Jr. <walrod@...>; R Kiehn <rkiehn2352@...>; Carlos Castro <czarlosromanov@...>; Dave Williams <djw0305@...>; Robert Becker <roberte.becker@...>; Геннадий Шипов <warpdrive09@...>; Eric Krieg Krieg <eric@...>; Eric Davis <tachyondavis@...>; "antigray ," <ANTIGRAY@...>
        Sent: Thu, April 1, 2010 2:20:29 AM
        Subject: Re: Zielinski's misreading of Einstein's actual text "homogeneous in the first approximation"

        Jack, I believe you've just scored yet another of your world famous "own goals" here.

        When he refers to a "homogeneous" gravitational field, Einstein is not talking about a uniform frame acceleration field.
        He is talking about an *actual* gravity field of uniform field strength. 

        There is no problem with defining such a field operationally, since test object acceleration can always be measured at 
        every point at *zero test object velocity*, eliminating any SR-related effects. 

        So what Einstein has in mind here when he uses the term "homogeneous to first order" is the non-vanishing curvature 
        associated with typical gravity fields produced by matter.

        Now it is nevertheless true that a RIndler frame (relativistic accelerating frame of reference) does exhibit such SR-type 
        effects -- but this is just another argument against Einstein's proposed principle, since it ensures that the phenomena observed 
        in such a frame differ from those observed from a non-accelerating frame even in the presence of a perfectly homogeneous 
        gravity field (Einstein's best case).

        So yes Einstein was later forced to retreat even from this version of the principle, even given his best case of a perfectly 
        homogeneous ("certain kind of") gravity field compared with a uniform acceleration field, eventually restricting the principle to what 
        we like to call "local" observations, irrespective of the question of spacetime curvature.

        You don't seem to realize that this is an argument *against* Einstein's original concept of equivalence, not for it.

        In any case, even if one is restricted to pure local observations, the principle as stated still does not work. Why? Because you 
        cannot 
        recover non-tidal gravitational acceleration -- a locally observable phenomenon -- from *any* kind of frame acceleration, 
        either
         globally or locally!

        You can always bring a test object as close as you like to a source boundary, and locally measure its acceleration with respect
        to the source. Such locally observable gravitational acceleration will not be observed in *any* kind of frame acceleration field. Which
        means that Einstein's proposed principle as stated is simply false: the laws observed even in a perfectly homogeneous gravity
        field are not the same as those observed in a homogeneous gravitational field -- not even approximately.

        Vilenkin's vacuum domain wall solutions, in which the vacuum geometry is completely Riemann flat,  show that this kind of situation 
        does exist in 1916 GR. A test object released near such a gravitational source will experience locally observable gravitational 
        acceleration with respect to the source, which will not be observed in *any* pure frame acceleration field with the gravitational source 
        switched off (by which I mean a Rindler frame in a Minkowski spacetime -- a pure frame acceleration field). 

        So the only way to get Einstein's principle as stated to work is to ignore the phenomenon of gravitational acceleration. But what kind of a
        "theory of gravity" can be based on such a principle?

        My answer here is simple: Einstein's version of the equivalence principle is simply not supported by his 1916 theory of gravity. It is
        simply a figment of Einstein's fevered imagination.

        Which is what I've been saying all along.

        Z.


        On Wed, Mar 31, 2010 at 6:41 PM, JACK SARFATTI <sarfatti@...> wrote:

        As I have been trying to explain to Zielinski without success is that such a global uniform gravity field does not exist because of special relativity time dilation and length contraction - I mean it does not exist in same sense that it would in Newton's gravity theory using only the v/c ---> 0 Galilean group limit of the Lorentz subgroup of the Poincare group. Einstein was perfectly aware of this in the quote Zielinski cites - Zielinski simply does not understand Einstein's text in my opinion.

         
        On Mar 31, 2010, at 6:23 PM, Paul Murad wrote:

        A "paradoxical" property

        Note that Rindler observers with smaller constant x coordinate are accelerating harder to keep up! This may seem surprising because in Newtonian physics, observers who maintain constant relative distance must share thesame acceleration. But in relativistic physics, we see that the trailing endpoint of a rod which is accelerated by some external force (parallel to its symmetry axis) must accelerate a bit harder than the leading endpoint, or else it must ultimately break. This is a manifestation of Lorentz contraction. As the rod accelerates its velocity increases and its length decreases. Since it is getting shorter, the back end must accelerate harder than the front. This leads to a differential equation showing, that at some distance, the acceleration of the trailing end diverges, resulting in the #The Rindler horizon.
        This phenomenon is the basis of a well known "paradox". However, it is a simple consequence of relativistic kinematics. One way to see this is to observe that the magnitude of the acceleration vector is just the path curvature of the corresponding world line. But the world lines of our Rindler observers are the analogs of a family of concentric circles in the Euclidean plane, so we are simply dealing with the Lorentzian analog of a fact familiar to speed skaters: in a family of concentric circles, inner circles must bend faster (per unit arc length) than the outer ones.
        Paul:

        Okay. I just want to make sure we are on the same sheet of music...
        Ufoguy...


        From: Paul Zielinski <iksnileiz@...>
        To: Paul Murad <ufoguypaul@...>

        Sent: Wed, March 31, 2010 8:56:03 PM
        Subject: Re: Zielinski's misreading of Einstein's actual text

        In this context "homogeneous" simply means that the gravitational field strength is uniform at all 
        points in some region of space.  

        I suppose what we really mean here is a *static* homogeneous gravitational field, which doesn't
        vary in time.

        On Wed, Mar 31, 2010 at 5:42 AM, Paul Murad <ufoguypaul@...> wrote:
        Paul:
         
        When you say locally homogeneous, to me that does not mean homogeneous at all but can represent a large multi-connected region that consists of elements that are inhomogenous.
        To me homogeneous means going on forever and having the same consistency.  If I was building a propulsor that involved controlling gravity, it would from a distance represent a singularity within a homogeneous field.
        Ufoguy...


        From: Paul Zielinski <iksnileiz@...>
        To: Paul Murad <ufoguypaul@...>

        Sent: Tue, March 30, 2010 7:04:02 PM

        Subject: Re: Zielinski's misreading of Einstein's actual text

        Actually it's the other way around -- an accelerating frame produces the Einstein equivalent of a perfectly
        homogeneous gravitational field.

        For the purposes of my current objection to Einstein's principle the field only has to be *locally* homogeneous, 
        since a test particle experiences gravitational acceleration with respect to a source if and only if the first coordinate-
        covariant derivatives g_uv: w of the metric are locally non-zero. In a flat spacetime, the first coordinate-covariant derivatives
        of the metric are all zero, although the non-covariant partial derivatives g_uv, w of the metric are not all zero in accelerating 
        frames. 

        So the technical details about what kind of source is required to produce a locally homogeneous field are
        not really important here. If you're interested in this, however, Vilenkin has published papers on a vacuum domain 
        wall that according to the GR fielld equations acts as the source of a flat field everywhere outside the wall. 

        Of course the field produced by a "planet" -- like any other spherically symmetric source in GR -- is not at all homogeneous. 


        On Tue, Mar 30, 2010 at 5:40 AM, Paul Murad <ufoguypaul@...> wrote:
        Paul:
         
        I have to assume that your use of homogeneous gravitational field implies one created by a planet while one could argue that an inhomogeneous gravitational field would be one derived from a propulsion system.  Is that correct?
        Paul...


        From: Paul Zielinski <iksnileiz@...>
        To: JACK SARFATTI <sarfatti@...>

        Sent: Tue, March 30, 2010 5:15:27 AM
        Subject: Re: Zielinski's misreading of Einstein's actual text

        I guess you missed the point that even if the gravity field is perfectly homogeneous and the frame acceleration
        field is completely uniform, and the observations are entirely "local", Einstein's version of EP still doesn't work,
        since you cannot get locally observable gravitational acceleration from *any* kind of frame acceleration.

        In any case there is nothing in Einstein's 1916 definition of "equivalence" that refers to locality. He claims that the laws 
        satisfied by a homogeneous gravity field are exactly the same as those satisfied by a uniform frame acceleration
        field. Which is simply false, as I've explained, even if all observations are kept strictly "local".

        If the gravity field is homogeneous, then there is no question of "first approximation" -- the equivalence would have
        to be exact. 

        JACK SARFATTI wrote:
        In fact Paul you simply have made an elementary error in reading the text you blanked out at

        "(homogeneous in the first approximation)"

        this clearly means local frame - not global frame 


        On Mar 29, 2010, at 11:47 PM, Paul Zielinski wrote:

        JACK SARFATTI wrote:
        You are mis-reading the text Paul. In many other places Einstein makes clear he does not mean this globally, only locally.
        Later -- under heavy criticism -- Einstein did modify this categorical version of the principle. But the original version states clearly that 
        with respect to the known laws of physics at least a globally homogeneous ("a certain kind of") gravitational field can "in all 
        strictness" be substituted for a frame acceleration field without *any* of the known laws of physics being violated.


        the equivalence principle has two facets

        1) Newton's gravity force is eliminated at the COM of an LNIF

        2) Newton's gravity force is the inertial force in a very special STATIC LNIF

        end of story

        PS Einstein never used "globally homogeneous" that's false.

        On Mar 30, 2010, at 12:00 AM, Paul Zielinski wrote:

        Jack, however you want to slice and dice this, even t'Hooft writes that Einstein misunderstood GR in the
        early days. t'Hooft clearly doesn't buy into Einstein's original version of EP either!

        Einstein clearly understood that his frames K & K' are local frames.

        Also there is no such thing even in special relativity as a uniform gravity field extending over all space! Look at the Rindler problem!

        A "paradoxical" property

        Note that Rindler observers with smaller constant x coordinate are accelerating harder to keep up! This may seem surprising because in Newtonian physics, observers who maintain constant relative distance must share thesame acceleration. But in relativistic physics, we see that the trailing endpoint of a rod which is accelerated by some external force (parallel to its symmetry axis) must accelerate a bit harder than the leading endpoint, or else it must ultimately break. This is a manifestation of Lorentz contraction. As the rod accelerates its velocity increases and its length decreases. Since it is getting shorter, the back end must accelerate harder than the front. This leads to a differential equation showing, that at some distance, the acceleration of the trailing end diverges, resulting in the #The Rindler horizon.
        This phenomenon is the basis of a well known "paradox". However, it is a simple consequence of relativistic kinematics. One way to see this is to observe that the magnitude of the acceleration vector is just the path curvature of the corresponding world line. But the world lines of our Rindler observers are the analogs of a family of concentric circles in the Euclidean plane, so we are simply dealing with the Lorentzian analog of a fact familiar to speed skaters: in a family of concentric circles, inner circles must bend faster (per unit arc length) than the outer ones.



        How is that different from Fock's observation that "Einstein didn't understand his own theory" (of gravity)?

        Forck was under Stalin's thumb - it was simple politics. He did not want to go to the Gulag like Landau. It's as if the US was run by Scientology!

        What t'Hooft does not acknowledge in his diatribe is that the modern "infinitesimal" version of EP does
        not support Einstein's concept of "general relativity".

        Paul that's silly nonsense in my opinion.

        That is the point at issue here.

        If you would just open your eyes it should be obvious that Einstein's classic version of the principle is simply
        not supported by actual known gravitational physics. Known laws of gravity physics are in fact violated -- 
        even locally -- when you substitute a homogeneous actual gravitational field for a frame acceleration field.

        Nonsense - this is Einstein's conception right here

        <Mail Attachment.jpeg>


        This is what is commonly meant in foundations of physics when it is said that from a contemporary 
        perspective the status of Einstein's general relativity concept is to be regarded as *purely heuristic*.

        Who cares? So what? It has no importance for any significant problem. All physics is purely heuristic. What else is new?
        Physics is not the same as mathematics. Physics uses mathematics, but there is nothing in physics that can be proved like a mathematical theorem is proved. 

        "As far as the laws of mathematics refer to reality, they are not certain, as far as they are certain, they do not refer to reality."

        If you are out to describe the truth, leave elegance to the tailor.
        Albert Einstein


        JACK SARFATTI wrote:

        On Mar 29, 2010, at 10:52 PM, Paul Zielinski wrote:

        So, is this what t'Hooft had in mind when he wrote,

        "They find some support from ancient publications by famous physicists; in the first decades of 
        the 20th century, indeed, Karl Schwarzschild, Hermann Weyl, and even Albert Einstein, had 
        misconceptions about the theory, which at that time was brand new, and these pioneers indeed 
        had not yet grasped the full implications. They can be excused for that, but today's professional 
        scientists know better
        ."

        Ironically, in the above t'Hooft appears to agree with my position that Einstein's original version
        of the EP (below) is not in fact supported by the modern version of GR.

        You see things in a very distorted way - way out of balance. On your particular point I have seen Einstein write explicitly he meant in the small!
        You are caught in a very trite quibble of no importance - in my opinion.

        Which has been my position all along. What t'Hooft doesn't explicitly acknowledge here is 
        that among Einstein's "misconceptions" about his 1916 theory of gravity was his entire concept 
        of what he called "general relativity"!

        The critical point here is that the modern version of EP, unlike Einstein's classic version below, is 
        not a generalized relativity principle. It is merely a GR <-> SR correspondence principle, which is 
        only strictly valid (and need only be strictly valid) inside an infinitesimal spacetime region, and
        even then only with respect to a restricted subclass of "local" measurements.

        The onus, the burden of proof is on you to prove that your imagined difference here makes a significant difference to the foundations of physics. I think not. Prove me wrong.


        Paul Zielinski wrote:
        FYI, here is Einstein's clearest public statement of *his* version of the equivalence principle:



        Note the sentence "The assumption that one may treat K' as at rest in all strictness 
        without any laws of nature not being fulfilled with respect to K', I call the 'principle of 
        equivalence'
        ." 

        This is Einstein 1916, after publication of his 1916 theory of gravity. Straight from the
        horse's pen. This is the theoretical basis for Einstein's generalized relativity principle.

        There is no limitation to infinitesimal regions of spacetime in this version of the equivalence 
        principle. The physical identification of a uniform frame acceleration
         field with a globally 
        homogeneous gravity field is *categorical* with respect to the "known laws of physics".

        I am not saying (unlike Einstein himself) that such a principle is actually supported by 1916 
        GR. In fact I'm saying the opposite.

        Evidently you agree with me on this, and not with Einstein.

        Paul Zielinski wrote:


        On Mon, Mar 29, 2010 at 12:18 AM, JACK SARFATTI <sarfatti@...> wrote:
        there is no such thing as a global relativity principle in GR

        There is no such thing as a global equivalence principle in GR -- which means that there
        is no such thing as "general relativity", as originally conceived by Einstein, in 1916 GR.

        Einstein's original concept of "general relativity" was based on a globally valid generalized
        relativity principle. But it turns out that such a principle is *not supported* by 1916 GR. 

        Which is exactly what V. Fock argued in his book, "The Theory of Space Time and 
        Gravitation"
        , saying that "general relativity" was a misnomer.

        So after all you really agree with me on this. You just won't admit it.
         

        On Mar 28, 2010, at 9:27 PM, Paul Zielinski wrote:



        On Sun, Mar 28, 2010 at 5:03 PM, JACK SARFATTI <sarfatti@...> wrote:

        On Mar 28, 2010, at 4:08 PM, Paul Zielinski wrote:

        t'Hooft seems to believe that there is no difference between a generalized relativity principle and a mere
        correspondence principle. If that's what he thinks, then he's just wrong. 

        Frankly I don't understand your distinction and neither obviously does 't Hooft.

        In that case neither of you understands Einstein. The fact of the matter here is that Einstein's equivalence 
        principle was global, not local -- as it must be to serve as a generalized relativity principle.'

        Hogwash - in fact ridiculous - 't Hooft has a Nobel and deserved it.

        I have no doubt. 

        Your assertion that Einstein's principle was never intended to be global is just false. 
         
        Suppose you turned out to be correct, so what?

        It changes our understanding of the physical meaning of GR, and may resolve difficulties reconciling GR
        with quantum gravity (including condensate theories).

        Hogwash - prove it with examples.

         
        What significant difference would it make?

        What immediate difference does Bohm's alternative interpretation of quantum mechanics make? 

        quite a bit - shown by Valentini

         
        In any case until you clearly explain what you mean precisely in the above jargon you are simply not communicating clearly.

        I think you understand the difference between a global relativity principle and a local correspondence principle.

        For one thing, a global relativity principle must hold for *all* observations, not just a restricted class of "local"
        measurements. 


        Of course I agree that the various stress-energy pseudotensors labeled "t_uv" are features of linearized
        GR, and as such do actually arise in GR from the non-linearity of the field equations. However, this does not 
        conflict with proposals like Yilmaz', for example, in which the field equations are linear and the solutions 
        are thus additive.

        Why only linearized? It's there in strong field also.

        In GR the stress-energy pseudotensors t_uv are artifacts of linearization. That's what t'Hooft himself says. There is
        no need for them in the exact solutions of the actual field equations.

        The real question is here is, can the non-linearity contribution to the GR vacuum  stress-energy be represented
        by a tensor quantity? I say yes it can, precisely because the GR field equations are fully covariant. And this has
        nothing to do with the modern version of EP.

        Prove it.


        My point here is that this should not be confused with the question of non-linearity of the field equations. 


        So t'Hooft is mixing up the issue of non-linearity of the GR field equations with the question of the localization
        and tensor character of the vacuum stress energy. These are all distinct issues. 

        On Sun, Mar 28, 2010 at 2:07 PM, JACK SARFATTI <sarfatti@...> wrote:
        Read the complete article by 't Hooft at http://www.phys.uu.nl/~thooft/gravitating_misconceptions.html

        excerpts - my comments in [ ... ] unless I say to the contrary, I agree with the quoted excerpts. I want it to be clear that I am a "radical conservative" in John Archibald Wheeler's sense. I think mainstream quantum theory and relativity are correct. All physical theories have limited domains of validity in David Bohm's sense, but all extensions of mainstream physics theories must limit to them, e.g. Antony Valentini's post-quantum theory with "signal nonlocality" violating "no-cloning" "passion at a distance" (A. Shimony) in sub-quantal non-equilibrium of the particle trajectories and classical field configuration "hidden variables" http://eprintweb.org/S/authors/All/va/Valentini

        As should be clear from my past discussions with Z, I definitely agree with 't Hooft's:

        "These self proclaimed scientists in turn blame me of "not understanding functional analysis". Indeed, L maintains that there is a difference between a  mathematical calculation and its physical interpretation, which I do not understand. He makes a big point about Einstein's "equivalence principle" being different from the "correspondence principle", and everyone, like me, who says that they in essence amount to being the same thing, if you want physical reality to be described by mathematical models, doesn't understand a thing or two. True. Nonsensical statements I often do not understand. What I do understand is that both ways of phrasing this principle require that one focuses on infinitesimally tiny space-time volume elements."

        &

        "I emphasize that any modification of Einstein's equations into something like  R μν  - 1/2 R gμν κ(Tμν + t μν (grav))   where  t μν (grav)   would be something like a "gravitational contribution" to the stress-energy-momentum tensor, is blatantly wrong.   Writing such a proposal betrays a complete misunderstanding of what General Relativity is about. The energy and momentum of the gravitational field is completely taken into account by the non-linear parts of the original equation. This can be understood and proven easily, as I explained in the main text.  Note that a freely falling observer experiences no gravitational field and no energy-momentum transfer; hence there cannot be a covariant tensor such as  t μν (grav) ."

        STRANGE MISCONCEPTIONS OF GENERAL RELATIVITY

        G. 't Hooft

        ..

        Physicists who write research papers, lecture notes and text books on the subject of General Relativity - like me - often receive mails by amateur scientists with remarks and questions. Many of these show a genuine interest in the subject. Their requests for further explanations, as well as their descriptions of deeper thoughts about the subject, are often interesting enough to try to answer them, and sometimes discussions result that are worthwhile. 


        However, there is also a group of people, calling themselves scientists, who claim that our lecture notes, text books and research papers are full of fundamental mistakes, thinking they have made earth shaking discoveries themselves that will upset much of our conventional wisdom.  Indeed, it often happens in science that a minority of dissenters try to dispute accepted wisdom. There's nothing wrong with that; it keeps us sharp, and, very occasionally, accepted wisdom might need modifications. Usually however, the dissenters have it totally wrong, and when the theory in question is Special or General Relativity, this is practically always the case.  Fortunately, science needs not defend itself. Wrong papers won't make it through history, and totally ignoring them suffices. Yet, there are reasons for a sketchy analysis of the mistakes commonly made. They are instructive for students of the subject, and I also want to learn from these mistakes myself, because making errors is only human, and it is important to be able to recognize erroneous thinking from as far away as one can ...

        Examples of the themes that we regularly encounter are:
        - "Einstein's equations for gravity are incorrect";
        - "Einstein's equivalence principle is incorrect or not correctly understood";
        - "Black holes do not exist";
        - "Einstein's equations have no dynamical solutions";
        - "Gravitational waves do not exist";
        - "The Standard Model is wrong";
        - "Cosmic background radiation does not exist";
        and so on.

        When confronted with claims of this sort, my first reaction is to politely explain why they are mistaken, attempting to identify the erroneous ideas on which they must be based. Occasionally, however, I thought that someone was just reporting things he had read elsewhere, and my response was more direct: "Never have I seen so much nonsense in one single package ..." or words of similar nature. This, of course, was a mistake, because these had been the thoughts of that person himself. When other correspondents also continued to defend concoctions that I thought to have extensively exposed as unfounded, I again felt tempted to use more direct language. So now I am a villain.

        [ I sympathize. ;-)]


        A curious thing subsequently happened. A handful of people with seriously flawed notions of general relativity apparently joined forces, and are now sending me more and more offensive emails, purportedly exposing my "stupidity" and collecting more "scientific" arguments to back their views.

        They find some support from ancient publications by famous physicists; in the first decades of the 20th century, indeed, Karl Schwarzschild, Hermann Weyl, and even Albert Einstein, had misconceptions about the theory, which at that time was brand new, and these pioneers indeed had not yet grasped the full implications. They can be excused for that, but today's professional scientists know better.

        As for my "stupidity", my own knowledge of the theory does not come from blindly accepting wisdom from text books; text books do contain mistakes, so I only accept scientific facts when I fully understand the arguments on which they are based. I feel no need whatsoever to defend standard scientific wisdom; I only defend the findings of which I have irrefutable evidence, and it so happens that most of these are indeed agreed upon by practically all experts in the field.

        The mails I have sent to my "scientific opponents" appear to be a waste of time and effort, so now I use this site to carefully explain where their arguments go astray. Rather than trying to bring them to their senses (which would be about as effective as trying to bring Jehovah's Witnesses to their senses), I rather address students who might otherwise be misled by what they read on the Internet. The people whose "ideas" I will discuss will be denoted by single initials, for understandable reasons.


        From their reactions it became clear that analyzing someone's mistaken train of thought is far from easy. What exactly are the blind spots? I try to spot these, but I receive furious responses that only suggest that the blind spots must be elsewhere. Where do their incorrect assertions come from? Of course, the mathematical equations at those points are missing, so I start guessing. I had to modify some of the guesses I made earlier on this page; actually, I prefer to explain how the math goes, and why the physical world is described by it.

        This is not intended as a scientific article, since after all, the math can be obtained from many existing text books. Sadly, these text books are "dismissed" as being "erroneous". Clearly, therefore, I won't be completely successful. To the students I insist: most of the text books bei

        (Message over 64 KB, truncated)

      • Paul Murad
        Jack: And we are of course assuming that the gravity tensor only has non-zero elements on the main diagonal and is symmetric.  Right? Another great
        Message 3 of 3 , Apr 2, 2010
        • 0 Attachment
          Jack:
           
          And we are of course assuming that the gravity tensor only has non-zero elements on the main diagonal and is symmetric.  Right?
           
          Another great soimplification...
          Ufoguy...


          From: Paul Zielinski <iksnileiz@...>
          To: JACK SARFATTI <sarfatti@...>
          Cc: Paul Murad <ufoguypaul@...>; Sarfatti_Physics_Seminars <Sarfatti_Physics_Seminars@yahoogroups.com>; "SarfattiScienceSeminars@YahooGroups. com" <SarfattiScienceSeminars@yahoogroups.com>; David Gladstone <d14947@...>; nick herbert <quanta@...>; S-P Sirag <sirag@...>; COLIN BENNET <sharkley1@...>; Mark Pesses Pesses <MPOGO@...>; David Kaiser <dikaiser@...>; Sharon Weinberger <sharonweinberger@...>; Gary Bekkum <garybekkum@...>; James Woodward <jfwoodward@...>; David McMahon <dmmcmah@...>; Creon Levit <creon.levit@...>; Hal Puthoff <Puthoff@...>; Waldyr A. Rodrigues Jr. <walrod@...>; R Kiehn <rkiehn2352@...>; Carlos Castro <czarlosromanov@...>; Dave Williams <djw0305@...>; Robert Becker <roberte.becker@...>; Геннадий Шипов <warpdrive09@...>; Eric Krieg Krieg <eric@...>; Eric Davis <tachyondavis@...>; "antigray ," <ANTIGRAY@...>
          Sent: Thu, April 1, 2010 11:32:25 PM
          Subject: Re: Murad's misunderstanding of Einstein's GR

          I agree with everything Jack says below, except the last part.

          On Thu, Apr 1, 2010 at 11:24 AM, JACK SARFATTI <sarfatti@...> wrote:
          No, you are garbling two definitions of "gravitational field".

          In simplest case in GR for static LNIF detectors, for a static, spherically symmetric source outside its event horizon (assuming it's a black hole)

          g00 = 1 + 2VNewton/c^2) = - 1/grr

          OK.

          The gravitational field Einstein means in his "equivalence principle" is not the curvature at all. It is the same g-force (per unit test mass) every fighter pilot is familiar with.

          g = - dVNewton/dr

          VNewton = - GM/r

          OK.

          The curvature is the variation of the g-force, i.e. second order partial derivatives of VNewton.

          It is a covariant measure of the differential variation of the g-force along the spacetime manifold.

          What Zielinski means by a uniform gravity field is

          VNewton = gz 

          Right. Which is exactly what Einstein meant.

          Obviously, the second order partial derivatives vanish, therefore the curvature tensor is zero.

          OK.

          Although, the curvature tensor is the covariant curl of the connection, since the connection is zero in LIFs, the curvature tensor really is zero under these conditions.

          Bzzzzt! Not OK!

          Jack you know very well that if the Riemann tensor R^u_vwl(x) does not vanish at some spacetime point x in any given CS,
          then it is not zero at x in every other. So clearly this cannot be true: no coordinate transformation from an LNIF to an
          LIF can
          zero out the Riemann curvature tensor.

          R^u_vwl(
          x) =/= 0 unless R^u'_v'w'l'(x) = 0 in every other frame.

          Z.




          On Apr 1, 2010, at 6:30 AM, Paul Murad wrote:

          Guys:
           
          Look at what you are really saying.  For a uniform gravitational field, you are saying that the curvature of the space-time continuum is none zero and is a constant.  How long can that go on?
           
          Thus it is reasonable to say that you are only looking at a portion of the space-time continuum where the curvature is constant and the space is within a specific domain so that you do not have to treat large gradients or edge effects.
           
          I think that would be entirely reasonable.
          Ufoguy....


          From: Paul Zielinski <iksnileiz@...>
          To: JACK SARFATTI <sarfatti@...>
          Cc: Paul Murad <ufoguypaul@...>; Sarfatti_Physics_Seminars <Sarfatti_Physics_Seminars@yahoogroups.com>; "SarfattiScienceSeminars@YahooGroups. com" <SarfattiScienceSeminars@yahoogroups.com>; David Gladstone <d14947@...>; nick herbert <quanta@...>; S-P Sirag <sirag@...>; COLIN BENNET <sharkley1@...>; Mark Pesses Pesses <MPOGO@...>; David Kaiser <dikaiser@...>; Sharon Weinberger <sharonweinberger@...>; Gary Bekkum <garybekkum@...>; James Woodward <jfwoodward@...>; David McMahon <dmmcmah@...>; Creon Levit <creon.levit@...>; Hal Puthoff <Puthoff@...>; Waldyr A. Rodrigues Jr. <walrod@...>; R Kiehn <rkiehn2352@...>; Carlos Castro <czarlosromanov@...>; Dave Williams <djw0305@...>; Robert Becker <roberte.becker@...>; Геннадий Шипов <warpdrive09@...>; Eric Krieg Krieg <eric@...>; Eric Davis <tachyondavis@...>; "antigray ," <ANTIGRAY@...>
          Sent: Thu, April 1, 2010 2:20:29 AM
          Subject: Re: Zielinski's misreading of Einstein's actual text "homogeneous in the first approximation"

          Jack, I believe you've just scored yet another of your world famous "own goals" here.

          When he refers to a "homogeneous" gravitational field, Einstein is not talking about a uniform frame acceleration field.
          He is talking about an *actual* gravity field of uniform field strength. 

          There is no problem with defining such a field operationally, since test object acceleration can always be measured at 
          every point at *zero test object velocity*, eliminating any SR-related effects. 

          So what Einstein has in mind here when he uses the term "homogeneous to first order" is the non-vanishing curvature 
          associated with typical gravity fields produced by matter.

          Now it is nevertheless true that a RIndler frame (relativistic accelerating frame of reference) does exhibit such SR-type 
          effects -- but this is just another argument against Einstein's proposed principle, since it ensures that the phenomena observed 
          in such a frame differ from those observed from a non-accelerating frame even in the presence of a perfectly homogeneous 
          gravity field (Einstein's best case).

          So yes Einstein was later forced to retreat even from this version of the principle, even given his best case of a perfectly 
          homogeneous ("certain kind of") gravity field compared with a uniform acceleration field, eventually restricting the principle to what 
          we like to call "local" observations, irrespective of the question of spacetime curvature.

          You don't seem to realize that this is an argument *against* Einstein's original concept of equivalence, not for it.

          In any case, even if one is restricted to pure local observations, the principle as stated still does not work. Why? Because you 
          cannot 
          recover non-tidal gravitational acceleration -- a locally observable phenomenon -- from *any* kind of frame acceleration, 
          either
           globally or locally!

          You can always bring a test object as close as you like to a source boundary, and locally measure its acceleration with respect
          to the source. Such locally observable gravitational acceleration will not be observed in *any* kind of frame acceleration field. Which
          means that Einstein's proposed principle as stated is simply false: the laws observed even in a perfectly homogeneous gravity
          field are not the same as those observed in a homogeneous gravitational field -- not even approximately.

          Vilenkin's vacuum domain wall solutions, in which the vacuum geometry is completely Riemann flat,  show that this kind of situation 
          does exist in 1916 GR. A test object released near such a gravitational source will experience locally observable gravitational 
          acceleration with respect to the source, which will not be observed in *any* pure frame acceleration field with the gravitational source 
          switched off (by which I mean a Rindler frame in a Minkowski spacetime -- a pure frame acceleration field). 

          So the only way to get Einstein's principle as stated to work is to ignore the phenomenon of gravitational acceleration. But what kind of a
          "theory of gravity" can be based on such a principle?

          My answer here is simple: Einstein's version of the equivalence principle is simply not supported by his 1916 theory of gravity. It is
          simply a figment of Einstein's fevered imagination.

          Which is what I've been saying all along.

          Z.


          On Wed, Mar 31, 2010 at 6:41 PM, JACK SARFATTI <sarfatti@...> wrote:

          As I have been trying to explain to Zielinski without success is that such a global uniform gravity field does not exist because of special relativity time dilation and length contraction - I mean it does not exist in same sense that it would in Newton's gravity theory using only the v/c ---> 0 Galilean group limit of the Lorentz subgroup of the Poincare group. Einstein was perfectly aware of this in the quote Zielinski cites - Zielinski simply does not understand Einstein's text in my opinion.

           
          On Mar 31, 2010, at 6:23 PM, Paul Murad wrote:

          A "paradoxical" property

          Note that Rindler observers with smaller constant x coordinate are accelerating harder to keep up! This may seem surprising because in Newtonian physics, observers who maintain constant relative distance must share thesame acceleration. But in relativistic physics, we see that the trailing endpoint of a rod which is accelerated by some external force (parallel to its symmetry axis) must accelerate a bit harder than the leading endpoint, or else it must ultimately break. This is a manifestation of Lorentz contraction. As the rod accelerates its velocity increases and its length decreases. Since it is getting shorter, the back end must accelerate harder than the front. This leads to a differential equation showing, that at some distance, the acceleration of the trailing end diverges, resulting in the #The Rindler horizon.
          This phenomenon is the basis of a well known "paradox". However, it is a simple consequence of relativistic kinematics. One way to see this is to observe that the magnitude of the acceleration vector is just the path curvature of the corresponding world line. But the world lines of our Rindler observers are the analogs of a family of concentric circles in the Euclidean plane, so we are simply dealing with the Lorentzian analog of a fact familiar to speed skaters: in a family of concentric circles, inner circles must bend faster (per unit arc length) than the outer ones.
          Paul:

          Okay. I just want to make sure we are on the same sheet of music...
          Ufoguy...


          From: Paul Zielinski <iksnileiz@...>
          To: Paul Murad <ufoguypaul@...>

          Sent: Wed, March 31, 2010 8:56:03 PM
          Subject: Re: Zielinski's misreading of Einstein's actual text

          In this context "homogeneous" simply means that the gravitational field strength is uniform at all 
          points in some region of space.  

          I suppose what we really mean here is a *static* homogeneous gravitational field, which doesn't
          vary in time.

          On Wed, Mar 31, 2010 at 5:42 AM, Paul Murad <ufoguypaul@...> wrote:
          Paul:
           
          When you say locally homogeneous, to me that does not mean homogeneous at all but can represent a large multi-connected region that consists of elements that are inhomogenous.
          To me homogeneous means going on forever and having the same consistency.  If I was building a propulsor that involved controlling gravity, it would from a distance represent a singularity within a homogeneous field.
          Ufoguy...


          From: Paul Zielinski <iksnileiz@...>
          To: Paul Murad <ufoguypaul@...>

          Sent: Tue, March 30, 2010 7:04:02 PM

          Subject: Re: Zielinski's misreading of Einstein's actual text

          Actually it's the other way around -- an accelerating frame produces the Einstein equivalent of a perfectly
          homogeneous gravitational field.

          For the purposes of my current objection to Einstein's principle the field only has to be *locally* homogeneous, 
          since a test particle experiences gravitational acceleration with respect to a source if and only if the first coordinate-
          covariant derivatives g_uv: w of the metric are locally non-zero. In a flat spacetime, the first coordinate-covariant derivatives
          of the metric are all zero, although the non-covariant partial derivatives g_uv, w of the metric are not all zero in accelerating 
          frames. 

          So the technical details about what kind of source is required to produce a locally homogeneous field are
          not really important here. If you're interested in this, however, Vilenkin has published papers on a vacuum domain 
          wall that according to the GR fielld equations acts as the source of a flat field everywhere outside the wall. 

          Of course the field produced by a "planet" -- like any other spherically symmetric source in GR -- is not at all homogeneous. 


          On Tue, Mar 30, 2010 at 5:40 AM, Paul Murad <ufoguypaul@...> wrote:
          Paul:
           
          I have to assume that your use of homogeneous gravitational field implies one created by a planet while one could argue that an inhomogeneous gravitational field would be one derived from a propulsion system.  Is that correct?
          Paul...


          From: Paul Zielinski <iksnileiz@...>
          To: JACK SARFATTI <sarfatti@...>

          Sent: Tue, March 30, 2010 5:15:27 AM
          Subject: Re: Zielinski's misreading of Einstein's actual text

          I guess you missed the point that even if the gravity field is perfectly homogeneous and the frame acceleration
          field is completely uniform, and the observations are entirely "local", Einstein's version of EP still doesn't work,
          since you cannot get locally observable gravitational acceleration from *any* kind of frame acceleration.

          In any case there is nothing in Einstein's 1916 definition of "equivalence" that refers to locality. He claims that the laws 
          satisfied by a homogeneous gravity field are exactly the same as those satisfied by a uniform frame acceleration
          field. Which is simply false, as I've explained, even if all observations are kept strictly "local".

          If the gravity field is homogeneous, then there is no question of "first approximation" -- the equivalence would have
          to be exact. 

          JACK SARFATTI wrote:
          In fact Paul you simply have made an elementary error in reading the text you blanked out at

          "(homogeneous in the first approximation)"

          this clearly means local frame - not global frame 


          On Mar 29, 2010, at 11:47 PM, Paul Zielinski wrote:

          JACK SARFATTI wrote:
          You are mis-reading the text Paul. In many other places Einstein makes clear he does not mean this globally, only locally.
          Later -- under heavy criticism -- Einstein did modify this categorical version of the principle. But the original version states clearly that 
          with respect to the known laws of physics at least a globally homogeneous ("a certain kind of") gravitational field can "in all 
          strictness" be substituted for a frame acceleration field without *any* of the known laws of physics being violated.


          the equivalence principle has two facets

          1) Newton's gravity force is eliminated at the COM of an LNIF

          2) Newton's gravity force is the inertial force in a very special STATIC LNIF

          end of story

          PS Einstein never used "globally homogeneous" that's false.

          On Mar 30, 2010, at 12:00 AM, Paul Zielinski wrote:

          Jack, however you want to slice and dice this, even t'Hooft writes that Einstein misunderstood GR in the
          early days. t'Hooft clearly doesn't buy into Einstein's original version of EP either!

          Einstein clearly understood that his frames K & K' are local frames.

          Also there is no such thing even in special relativity as a uniform gravity field extending over all space! Look at the Rindler problem!

          A "paradoxical" property

          Note that Rindler observers with smaller constant x coordinate are accelerating harder to keep up! This may seem surprising because in Newtonian physics, observers who maintain constant relative distance must share thesame acceleration. But in relativistic physics, we see that the trailing endpoint of a rod which is accelerated by some external force (parallel to its symmetry axis) must accelerate a bit harder than the leading endpoint, or else it must ultimately break. This is a manifestation of Lorentz contraction. As the rod accelerates its velocity increases and its length decreases. Since it is getting shorter, the back end must accelerate harder than the front. This leads to a differential equation showing, that at some distance, the acceleration of the trailing end diverges, resulting in the #The Rindler horizon.
          This phenomenon is the basis of a well known "paradox". However, it is a simple consequence of relativistic kinematics. One way to see this is to observe that the magnitude of the acceleration vector is just the path curvature of the corresponding world line. But the world lines of our Rindler observers are the analogs of a family of concentric circles in the Euclidean plane, so we are simply dealing with the Lorentzian analog of a fact familiar to speed skaters: in a family of concentric circles, inner circles must bend faster (per unit arc length) than the outer ones.



          How is that different from Fock's observation that "Einstein didn't understand his own theory" (of gravity)?

          Forck was under Stalin's thumb - it was simple politics. He did not want to go to the Gulag like Landau. It's as if the US was run by Scientology!

          What t'Hooft does not acknowledge in his diatribe is that the modern "infinitesimal" version of EP does
          not support Einstein's concept of "general relativity".

          Paul that's silly nonsense in my opinion.

          That is the point at issue here.

          If you would just open your eyes it should be obvious that Einstein's classic version of the principle is simply
          not supported by actual known gravitational physics. Known laws of gravity physics are in fact violated -- 
          even locally -- when you substitute a homogeneous actual gravitational field for a frame acceleration field.

          Nonsense - this is Einstein's conception right here

          <Mail Attachment.jpeg>


          This is what is commonly meant in foundations of physics when it is said that from a contemporary 
          perspective the status of Einstein's general relativity concept is to be regarded as *purely heuristic*.

          Who cares? So what? It has no importance for any significant problem. All physics is purely heuristic. What else is new?
          Physics is not the same as mathematics. Physics uses mathematics, but there is nothing in physics that can be proved like a mathematical theorem is proved. 

          "As far as the laws of mathematics refer to reality, they are not certain, as far as they are certain, they do not refer to reality."

          If you are out to describe the truth, leave elegance to the tailor.
          Albert Einstein


          JACK SARFATTI wrote:

          On Mar 29, 2010, at 10:52 PM, Paul Zielinski wrote:

          So, is this what t'Hooft had in mind when he wrote,

          "They find some support from ancient publications by famous physicists; in the first decades of 
          the 20th century, indeed, Karl Schwarzschild, Hermann Weyl, and even Albert Einstein, had 
          misconceptions about the theory, which at that time was brand new, and these pioneers indeed 
          had not yet grasped the full implications. They can be excused for that, but today's professional 
          scientists know better
          ."

          Ironically, in the above t'Hooft appears to agree with my position that Einstein's original version
          of the EP (below) is not in fact supported by the modern version of GR.

          You see things in a very distorted way - way out of balance. On your particular point I have seen Einstein write explicitly he meant in the small!
          You are caught in a very trite quibble of no importance - in my opinion.

          Which has been my position all along. What t'Hooft doesn't explicitly acknowledge here is 
          that among Einstein's "misconceptions" about his 1916 theory of gravity was his entire concept 
          of what he called "general relativity"!

          The critical point here is that the modern version of EP, unlike Einstein's classic version below, is 
          not a generalized relativity principle. It is merely a GR <-> SR correspondence principle, which is 
          only strictly valid (and need only be strictly valid) inside an infinitesimal spacetime region, and
          even then only with respect to a restricted subclass of "local" measurements.

          The onus, the burden of proof is on you to prove that your imagined difference here makes a significant difference to the foundations of physics. I think not. Prove me wrong.


          Paul Zielinski wrote:
          FYI, here is Einstein's clearest public statement of *his* version of the equivalence principle:



          Note the sentence "The assumption that one may treat K' as at rest in all strictness 
          without any laws of nature not being fulfilled with respect to K', I call the 'principle of 
          equivalence'
          ." 

          This is Einstein 1916, after publication of his 1916 theory of gravity. Straight from the
          horse's pen. This is the theoretical basis for Einstein's generalized relativity principle.

          There is no limitation to infinitesimal regions of spacetime in this version of the equivalence 
          principle. The physical identification of a uniform frame acceleration
           field with a globally 
          homogeneous gravity field is *categorical* with respect to the "known laws of physics".

          I am not saying (unlike Einstein himself) that such a principle is actually supported by 1916 
          GR. In fact I'm saying the opposite.

          Evidently you agree with me on this, and not with Einstein.

          Paul Zielinski wrote:


          On Mon, Mar 29, 2010 at 12:18 AM, JACK SARFATTI <sarfatti@...> wrote:
          there is no such thing as a global relativity principle in GR

          There is no such thing as a global equivalence principle in GR -- which means that there
          is no such thing as "general relativity", as originally conceived by Einstein, in 1916 GR.

          Einstein's original concept of "general relativity" was based on a globally valid generalized
          relativity principle. But it turns out that such a principle is *not supported* by 1916 GR. 

          Which is exactly what V. Fock argued in his book, "The Theory of Space Time and 
          Gravitation"
          , saying that "general relativity" was a misnomer.

          So after all you really agree with me on this. You just won't admit it.
           

          On Mar 28, 2010, at 9:27 PM, Paul Zielinski wrote:



          On Sun, Mar 28, 2010 at 5:03 PM, JACK SARFATTI <sarfatti@...> wrote:

          On Mar 28, 2010, at 4:08 PM, Paul Zielinski wrote:

          t'Hooft seems to believe that there is no difference between a generalized relativity principle and a mere
          correspondence principle. If that's what he thinks, then he's just wrong. 

          Frankly I don't understand your distinction and neither obviously does 't Hooft.

          In that case neither of you understands Einstein. The fact of the matter here is that Einstein's equivalence 
          principle was global, not local -- as it must be to serve as a generalized relativity principle.'

          Hogwash - in fact ridiculous - 't Hooft has a Nobel and deserved it.

          I have no doubt. 

          Your assertion that Einstein's principle was never intended to be global is just false. 
           
          Suppose you turned out to be correct, so what?

          It changes our understanding of the physical meaning of GR, and may resolve difficulties reconciling GR
          with quantum gravity (including condensate theories).

          Hogwash - prove it with examples.

           
          What significant difference would it make?

          What immediate difference does Bohm's alternative interpretation of quantum mechanics make? 

          quite a bit - shown by Valentini

           
          In any case until you clearly explain what you mean precisely in the above jargon you are simply not communicating clearly.

          I think you understand the difference between a global relativity principle and a local correspondence principle.

          For one thing, a global relativity principle must hold for *all* observations, not just a restricted class of "local"
          measurements. 


          Of course I agree that the various stress-energy pseudotensors labeled "t_uv" are features of linearized
          GR, and as such do actually arise in GR from the non-linearity of the field equations. However, this does not 
          conflict with proposals like Yilmaz', for example, in which the field equations are linear and the solutions 
          are thus additive.

          Why only linearized? It's there in strong field also.

          In GR the stress-energy pseudotensors t_uv are artifacts of linearization. That's what t'Hooft himself says. There is
          no need for them in the exact solutions of the actual field equations.

          The real question is here is, can the non-linearity contribution to the GR vacuum  stress-energy be represented
          by a tensor quantity? I say yes it can, precisely because the GR field equations are fully covariant. And this has
          nothing to do with the modern version of EP.

          Prove it.


          My point here is that this should not be confused with the question of non-linearity of the field equations. 


          So t'Hooft is mixing up the issue of non-linearity of the GR field equations with the question of the localization
          and tensor character of the vacuum stress energy. These are all distinct issues. 

          On Sun, Mar 28, 2010 at 2:07 PM, JACK SARFATTI <sarfatti@...> wrote:
          Read the complete article by 't Hooft at http://www.phys.uu.nl/~thooft/gravitating_misconceptions.html

          excerpts - my comments in [ ... ] unless I say to the contrary, I agree with the quoted excerpts. I want it to be clear that I am a "radical conservative" in John Archibald Wheeler's sense. I think mainstream quantum theory and relativity are correct. All physical theories have limited domains of validity in David Bohm's sense, but all extensions of mainstream physics theories must limit to them, e.g. Antony Valentini's post-quantum theory with "signal nonlocality" violating "no-cloning" "passion at a distance" (A. Shimony) in sub-quantal non-equilibrium of the particle trajectories and classical field configuration "hidden variables" http://eprintweb.org/S/authors/All/va/Valentini

          As should be clear from my past discussions with Z, I definitely agree with 't Hooft's:

          "These self proclaimed scientists in turn blame me of "not understanding functional analysis". Indeed, L maintains that there is a difference between a  mathematical calculation and its physical interpretation, which I do not understand. He makes a big point about Einstein's "equivalence principle" being different from the "correspondence principle", and everyone, like me, who says that they in essence amount to being the same thing, if you want physical reality to be described by mathematical models, doesn't understand a thing or two. True. Nonsensical statements I often do not understand. What I do understand is that both ways of phrasing this principle require that one focuses on infinitesimally tiny space-time volume elements."

          &

          "I emphasize that any modification of Einstein's equations into something like  R μν  - 1/2 R gμν κ(Tμν + t μν (grav))   where  t μν (grav)   would be something like a "gravitational contribution" to the stress-energy-momentum tensor, is blatantly wrong.   Writing such a proposal betrays a complete misunderstanding of what General Relativity is about. The energy and momentum of the gravitational field is completely taken into account by the non-linear parts of the original equation. This can be understood and proven easily, as I explained in the main text.  Note that a freely falling observer experiences no gravitational field and no energy-momentum transfer; hence there cannot be a covariant tensor such as  t μν (grav) ."

          STRANGE MISCONCEPTIONS OF GENERAL RELATIVITY

          G. 't Hooft

          ..

          Physicists who write research papers, lecture notes and text books on the subject of General Relativity - like me - often receive mails by amateur scientists with remarks and questions. Many of these show a genuine interest in the subject. Their requests for further explanations, as well as their descriptions of deeper thoughts about the subject, are often interesting enough to try to answer them, and sometimes discussions result that are worthwhile. 


          However, there is also a group of people, calling themselves scientists, who claim that our lecture notes, text books and research papers are full of fundamental mistakes, thinking they have made earth shaking discoveries themselves that will upset much of our conventional wisdom.  Indeed, it often happens in science that a minority of dissenters try to dispute accepted wisdom. There's nothing wrong with that; it keeps us sharp, and, very occasionally, accepted wisdom might need modifications. Usually however, the dissenters have it totally wrong, and when the theory in question is Special or General Relativity, this is practically always the case.  Fortunately, science needs not defend itself. Wrong papers won't make it through history, and totally ignoring them suffices. Yet, there are reasons for a sketchy analysis of the mistakes commonly made. They are instructive for students of the subject, and I also want to learn from these mistakes myself, because making errors is only human, and it is important to be able to recognize erroneous thinking from as far away as one can ...

          Examples of the themes that we regularly encounter are:
          - "Einstein's equations for gravity are incorrect";
          - "Einstein's equivalence principle is incorrect or not correctly understood";
          - "Black holes do not exist";
          - "Einstein's equations have no dynamical solutions";
          - "Gravitational waves do not exist";
          - "The Standard Model is wrong";
          - "Cosmic background radiation does not exist";
          and so on.

          When confronted with claims of this sort, my first reaction is to politely explain why they are mistaken, attempting to identify the erroneous ideas on which they must be based. Occasionally, however, I thought that someone was just reporting things he had read elsewhere, and my response was more direct: "Never have I seen so much nonsense in one single package ..." or words of similar nature. This, of course, was a mistake, because these had been the thoughts of that person himself. When other correspondents also continued to defend concoctions that I thought to have extensively exposed as unfounded, I again felt tempted to use more direct language. So now I am a villain.

          [ I sympathize. ;-)]


          A curious thing subsequently happened. A handful of people with seriously flawed notions of general relativity apparently joined forces, and are now sending me more and more offensive emails, purportedly exposing my "stupidity" and collecting more "scientific" arguments to back their views.

          They find some support from ancient publications by famous physicists; in the first decades of the 20th century, indeed, Karl Schwarzschild, Hermann Weyl, and even Albert Einstein, had misconceptions about the theory, which at that time was brand new, and these pioneers indeed had not yet grasped the full implications. They can be excused for that, but today's professional scientists know better.

          As for my "stupidity", my own knowledge of the theory does not come from blindly accepting wisdom from text books; text books do contain mistakes, so I only accept scientific facts when I fully understand the arguments on which they are based. I feel no need whatsoever to defend standard scientific wisdom; I only defend the findings of which I have irrefutable evidence, and it so happens that most of these are indeed agreed upon by practically all experts in the field.

          The mails I have sent to my "scientific opponents" appear to be a waste of time and effort, so now I use this site to carefully explain where their arguments go astray. Rather than trying to bring them to their senses (which would be about as effective as trying to bring Jehovah's Witnesses to their senses), I rather address students who might otherwise be misled by what they read on the Internet. The people whose "ideas" I will discuss will be denoted by single initials, for understandable reasons.


          From their reactions it became clear that analyzing someone's mistaken train of thought is far from easy. What exactly are the blind spots? I try to spot these, but I receive furious responses that only suggest that the blind spots must be elsewhere. Where do their incorrect assertions come from? Of course, the mathematical equations at those points are missing, so I start guessing. I had to modify some of the guesses I made earlier on this page; actually, I prefer to explain how the math goes, and why the physical world is described by it.

          This is not intended as a scientific article, since after all, the math can be obtained from many existing text books. Sadly, these text books are "dismissed" as being "erroneous". Clearly, therefore, I won't be completely successful. To the students I insist: most of the text books being criticized by those folks are actually very good, although it always pays to be critical, and whatever you read, check it with your own common sense.

          Here come some of the crazy assertions concerning General Relativity, and my responses.

          "Einstein's equations for gravity are incorrect,
          they have no dynamical solutions, and do not imply gravitational waves as described in numerous text books."

          Mr. L. makes this claim, and now he basically refers to a paper that he once managed to get published in a refereed journal. It is clear to me that the referee in question must have been inattentive. It happens more often that incorrect papers appear in refereed journals. Science is immune to that; false papers are simply being ignored, and so is this one; it is not being referred to by professional scientists (Spires mentions only one reference that is not by the author himself).


          Dynamical solutions means solutions that depend non-trivially on space as well as time. Numerous of such solutions are being generated routinely in research papers, but most of them require some sort of approximation techniques. The gravitational waves emitted by binary pulsars are typical examples. The procedure to obtain these solutions, using routines to solve Einstein's equations, is well-known and described in the text books. L. notes that approximations are not exact, and exact solutions do not exist.


          Approximations are of course used in many branches of physics. Some are reasonably accurate, some may be questionable. In the case of gravitational waves emitted by time-dependent massive objects, the approximations used are extremely accurate, and furthermore, any doubt can be removed by producing the next term in the approximation, which in many of these examples turns out to be completely negligible. L. does not have the mathematical abilities to do such calculations.

          It so happens that also exact, analytical solutions exist that depend non-trivially on space and time. I showed L how these solutions can be obtained in meticulous detail. In order to present and discuss a special example, one can simply assume cylindrical symmetry. This symmetry assumes that the solution is invariant under the transformations z  z + 

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