Friday, August 12, 2011

IJMPD, R. Tung, and a dodgy paper by B. Mashhoon

A reader who read about Fabien Besnard's experience in dealing with International Journal of Modern Physics D (IJMPD) concerning the case of Ahmad Rami El-Nabulsi was prompted to let us know about his own unsatisfactory experience with that journal.


First, here is the paper at issue, “Beyond Gravitoelectromagnetism: Critical Speed in Gravitational Motion” by B. Mashhoon”, IJMPD, 14, no. 12, (2005) pp. 2025-2037.
Mashhoon's IJMPD Paper

Our reader submitted to Editor-in-Chief R.S. Tung for publication this admirably clear refutation of the Mashhoon paper. Passages identifying him have been removed, but he is an expert at a top American university.
Rebuttal to Mashhoon

Tung wrote back:

Dear Dr. ....,

Many thanks for sending your manuscript "Comment: "..... by B. Mashhoon" to the International Journal of Modern Physics D. Our editors have read your paper, we would like to recommend that you submit your work elsewhere. We do not feel that your paper is appropriate for the accelerated publication of this journal.

which our reader considered an effort to "sweep the garbage under the rug". He answered "Isn't the note I sent you addressing a paper printed in YOUR journal ?" He reminded Tung of the Committee on Publication Ethics (COPE) guidelines (publicationethics.org) on correcting errors in the literature, and suggested three possible reviewers.

On May 13, our reader updated us:

It remains to be seen if IJMPD will publish my correction, the error in the originally published paper is evident. It is an acid test of their honesty. I will keep you posted as things unfold.

And on May 22:

They aren't going to publish it, its status is "With Editor", the code name for doing nothing and hoping that the embarrassment will go away. After a few months of "With Editor", they quietly take it off the website.

On July 15 the status of our reader's rebuttal changed to "Under Review", which was encouraging.

Around August 3 IJMPD's reviewer (not one of the three suggested by our reader) replied:

The author comments on a discussion of Newtonian approximation of Mashhoon [IJMPD 14 (2005) 2025-2037] on "critical speed" in gravitational motion. I find the discussion in Mashhoon's paper using linear approximation appropriate. This is not the situation to use the proper acceleration. This comment is incorrect, I recommend a rejection.

to which our reader responds

Actually, the error in the paper is that Mashoon doesn't know the difference between coordinate and proper acceleration and is basing his erroneous conclusions on using coordinate acceleration. IJMPD turns out to be a crackpot journal, publishes crackpot papers, uses incompetent referees and has a chief editor that desperately tries to sweep the dirt under the rug whenever confronted with rebuttals.

On August 10 our reader got this response from Editor-in-Chief R.S. Tung:

Dear prof.dr. ....,

Many thanks for sending your manuscript "Rebuttal to: "Beyond Gravitoelectromagnetism: Critical Speed in Gravitational Motion" by B. Mashhoon, ", IJMP D, 14,12,(2005) pp. 2025-2037" to the International Journal of Modern Physics D. Our editors and referee have read your rebuttal letter. We judge that the comment may not be of a sufficiently high standard to justify the full peer review.

All papers or comments accepted for publication in IJMPD journals must be novel, interesting and clearly written. The International Journal of Modern Physics D currently receives many more submissions than it can publish. Our editors will sometimes return a manuscript to the author(s) without review when they feel that it is unlikely to be accepted for publication. In this way, we seek to avoid delaying the author(s)' submission to another journal.

I hope that you will understand our decision not to consider your paper further.

Sincerely,

Journal Office
International Journal of Modern Physics D

Our reader wrote

I had to remind Mr. Tung that this is the SECOND time he and his cohorts tried to sweep the criticism under the rug and that he continues to be in violation of the fair publishing rules. I am tempted to put my paper on the internet, for everyone to see their dishonesty.

and thus the history comes to be preserved in this blog post. Thanks to our reader for keeping us informed as events unfolded. If there are further developments I'll add them here.


Translate English to Arabic
محمد النشائى El Naschie Watch محمد النشائي El Naschie News محمد النشائى محمد النشائي All El Naschie All The Time محمد النشائى
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65 comments:

  1. I am no expert on this topic, but it seems the paper being commented on is hardly of the El Naschie variety, in that it is well written by someone knowledgeable on the topic (though perhaps, admittedly, mistaken in it's analysis).

    Calling Mashoon a crackpot seems to me premature. The reader benefits greatly for doing this publicly in that he can now claim that this an El Naschie-type scam at IJMPD. However, the burden of proof for such a claim, if this is the claim, would appear to me very high.

    This could a genuine topic of scientific discussion that the reader and Mashoon could properly explore through a normal "Comment"/"Reply to Comment". It is very unfortunate that IJMPD did not do the correct thing by allowing (a properly reviewed, e.g., to remove inappropriate language) Comment followed by Mashoon's Reply. Instead we have this blog post, with its implied equivalencies, and no explanation of what is actually wrong. Worse, the author has had no chance to provide a high-level scientific reply; all-around very disturbing situation.

    ReplyDelete
  2. I agree that Mashhoon's paper is nonetheless much better than anything El Naschie has written.

    ReplyDelete
  3. We can only thank the dishonest of the IJMPD editors for this situation. Fabien (Besnard) suggested that I picked a paper on IJMPD and that I wrote a comment on its mistakes. The draw of luck was that I picked the Mashhoon paper. It is not a bad paper but it has some very serious error, nevertheless. Unfortunately, the editors of IJMPD would not do the honest thing of publishing my rebuttal. So, mashhoon is also robbed of the possibility of reply.

    ReplyDelete
  4. There are other complaints about Mashhoon articles, perhaps from the same correspondent (below), but that is all part of the scientific method. (Mashhoon does not edit his own journal, his publications have been reviewed and proofread, and he is Iranian not Egyptian.)
    IMMPD publication of El-Nabulsi's incoherent plagiarism remains far more shocking.

    arXiv:1108.3057
    Title: Mach's Principle: A Response to Mashhoon and Wesson's Paper arXiv: 1106.6036,
    Author: Julian Barbour
    In their recent "Mach's principle and higher-dimensional dynamics", Mashhoon and Wesson argue that Mach's principle is not properly incorporated into general relativity and that in Einstein's theory "the origin of inertia remains essentially the same as in Newtonian physics." While it is true that the motion of a single test particle in a Newtonian inertial frame of reference appears essentially the same as in an Einsteinian local inertial frame, this misses the point. The issue is not what motion looks like in an inertial frame of reference but what is the origin of the inertial frame. Unlike Newtonian dynamics, general relativity does implement Mach's principle when considered from this correctly formulated point of view.

    ReplyDelete
  5. Hi Slipper.Mystery! Wow, that was submitted to the arXiv just today. By the way our correspondent was not Julian Barbour.

    ReplyDelete
  6. Annalen der Physik is another journal that has gone way down in quality, I have pointed out to them quite a few papers that are dead wrong. As opposed to the dishonest IJMPD editors, the editors at Annalen are reviewing my rebuttals. Let's see how honest they are.....

    ReplyDelete
  7. By all means, please keep us informed.

    ReplyDelete
  8. Jason,

    as a longtime reader of your blog, it pains me to see that you might have fallen for the antics of a potentially El Naschie-like character.

    There are several troubling aspects in this incident.

    a) If this were a bona fide scientist facing the alleged situation (s)he would have simply posted the comment in the ArXiv. Everyone in this subfield of physics reads the ArXiv,
    in fact many more people than those who read IJMPD. Mashoon's paper appeared in the ArXiv.

    b) Are you sure of the reported facts? It appears you only heard one side of the story, a side that obviously has an axe to grind.

    c) Why anonymity? By posting this anonymously, it is unlikely that IJMPD will respond. Note that in Besnard's case IJMPD responded very proactively and he was in the end satisfied
    (and it appears it was the only journal which did).


    d) Then there is the comment itself. Far from being a "rebuttal of a paper" what it does is misunderstand a claim in the middle of the paper by Mashhoon (who never stated that the repulsion discussed was an observable effect). These limiting velocities have
    long been known to be coordinate artifacts. It is already mentioned in Moshe Carmeli's 1972 Lettere al Nuovo Cimento (right above equation 14), which is quoted by Mashhoon. That doesn't mean they are not useful as intermediate steps
    for other calculations that do have physical meaning.

    Summarizing, it appears to me that this post is not up to the usual high standards of this blog.

    ReplyDelete
  9. Hmmm. First, sorry your comment took a while to appear. It was stuck in the spam filter.

    You and the submitter of the "rebuttal" (whose identity is known to me and to IJMPD) know more about this than I do, so let's have him answer. If appropriate of course I'll take this post down and replace it with an apology to Mashhoon.

    ReplyDelete
  10. Immediately after eq(14) Mashhoon claims:

    "This equation contains a critical speed vc = 1/√3; that is, for motion with v < vc,
    we have the standard attractive force of gravity familiar from Newtonian physics, while for v = vc, the particle experiences no force and for v > vc the gravitational attraction turns to repulsion."

    The above is total nonsense, period. The "gravitational attraction turns into repulsion"? Seriously?

    ReplyDelete
  11. In the arXiv version I embedded, the quote comes just after equation 18. The sentence immediately after it is "These results are valid in the linear approximation for the gravitational field under consideration here." If Mashhoon means by that last sentence that the repulsion is not physical but only an artifact of the approximation method, then perhaps he has been done a disservice, but that's not how I read it. I'm not sure.

    ReplyDelete
  12. The sentence is crackpot in ANY interpretation, the point is that Mashhoon uses coordinate (instead of proper) acceleration to draw his conclusion. There is no physical attribute to coordinate acceleration, this is elementary physics.
    BTW, he's written another paper on the same subject, except he came up with the "critical" speed v_c=1/sqrt(2) instead of 1/sqrt(3). IJMPD simply publishes nonsense, maybe Mashhoon is not as bad as El-Naschie but he's bad enough, and so is the journal.

    ReplyDelete
  13. This paper by Blinnikov et al. (also reference 21 in Mashhoon's paper):

    Critical velocities c/sqrt(3) and c/sqrt(2) in the general theory of relativity

    deals with both critical speeds in the same fashion.

    This paragraph from the introduction is interesting:

    As found in papers [9-11], in the gravitational field of a spherically symmetric object (the Earth, the Sun, other stars) there exists a critical value of the coordinate speed v_c=c/sqrt(3). Particles moving radially with this speed do not accelerate or decelerate in the first order of the Newton constant G-thus,
    they 'ignore' gravity.


    What do you think of the "ignoring gravity" statement?

    P.S. References [9-11] are:

    9. Carmeli MLett. Nuovo Cimento 3 379 (1972)

    10. Carmeli M Classical Fields: General Relativity and Gauge Theory (New York: J. Wiley, 1982)

    11. Blinnikov S I, Okun L B, Vysotsky M I, gr-qc/0111103

    ReplyDelete
  14. From Blinikov's unpublished paper:

    "We define the critical coordinate velocity vc. A particle moving radially in Schwarzschild
    background with this velocity, vc = c/√3, is neither accelerated, nor decelerated
    if gravitational field is weak, rg ≪ r, where rg is the gravitational radius, while r is
    the current one. We find that the numerical coincidence of vc with velocity of sound
    in ultrarelativistic plasma, us, is accidental, since two velocities are different if the
    number of spatial dimensions is not equal to 3."

    Coordinate speed, coordinate acceleration, coordinate time are all USELESS in physics. What matters is proper speed, proper acceleration, proper time, etc. One cannot conclude anything about the physics of an experiment based on coordinate variables. So, Blinikov makes the same mistake as Mashhoon. The "critical" speed is just meaningless, there is no physical interpretation that can be associated with it.

    ReplyDelete
  15. When Mashhoon says "for v > vc the gravitational attraction turns to repulsion" he's wrong. Gravitation is never repulsive. Anonymous August 19, 2011 4:59 PM said Mashhoon "never stated that the repulsion discussed was an observable effect" but what else could Mashhoon have meant? If Mashhoon didn't think gravitational repulsion was physically observable, at least in principle, what was the meaning of his assertion "for v > vc the gravitational attraction turns to repulsion"?

    ReplyDelete
  16. In effect, Mashhoon published two papers that are nothing but a rehash of the incorrect paper by Blinnikov and Okun. Neither author seems to understand that the change of sign in coordinate velocity is an observer - dependent effect and that, in reality, the object keeps accelerating without ever "for v > vc the gravitational attraction turns to repulsion". Both papers should be retracted by their respective journals. Given that IJMPD refused to retract the much worse papers by El-Nabulsi, it seems highly unlikely that they will do the right thing.

    ReplyDelete
  17. If you Google "IJMPD", El Naschie Watch pages are among the top hits.

    ReplyDelete
  18. I've checked Carmeli's book (Classical Fields: General Relativity and Gauge Theory). On p. 230 one can read:

    Show that a particle with a speed close to the speed of light can experience a "slow-down" when moving in the Schwarzschild field. [See M. Carmeli, Nuovo Cimento Lett., 3. 379 (1972).]

    (the solution follows)

    Based on this one can deduce that Carmeli makes the same mistake as Blinnikov and Mashhoon.

    ReplyDelete
  19. This is far more unbelievable - the arXiv version of Mashhoon's paper (I don't know if the same applies to the IJMPD version) cites (see Reference 20) these two arXiv papers from F. S. Felber:

    Weak 'Antigravity' Fields in General Relativity

    Exact Relativistic 'Antigravity' Propulsion

    I don't know if Mashhoon by citing such crackpot papers acknowledge such a crackpot principle (i.e. antigravity), but it definitely rings a bell.

    ReplyDelete
  20. There's a whole community operating under this misapprehension?! The two arXiv papers by F.S. Felber are referenced by Slashdot and Physorg. Here's the entire Physorg article:

    Physicist to Present New Exact Solution of Einstein's Gravitational Field Equation

    New antigravity solution will enable space travel near speed of light by the end of this century, he predicts.

    On Tuesday, Feb. 14, noted physicist Dr. Franklin Felber will present his new exact solution of Einstein's 90-year-old gravitational field equation to the Space Technology and Applications International Forum (STAIF) in Albuquerque. The solution is the first that accounts for masses moving near the speed of light.

    Felber's antigravity discovery solves the two greatest engineering challenges to space travel near the speed of light: identifying an energy source capable of producing the acceleration; and limiting stresses on humans and equipment during rapid acceleration.

    "Dr. Felber's research will revolutionize space flight mechanics by offering an entirely new way to send spacecraft into flight," said Dr. Eric Davis, Institute for Advanced Studies at Austin and STAIF peer reviewer of Felber's work. "His rigorously tested and truly unique thinking has taken us a huge step forward in making near-speed-of-light space travel safe, possible, and much less costly."

    The field equation of Einstein's General Theory of Relativity has never before been solved to calculate the gravitational field of a mass moving close to the speed of light. Felber's research shows that any mass moving faster than 57.7 percent of the speed of light will gravitationally repel other masses lying within a narrow 'antigravity beam' in front of it. The closer a mass gets to the speed of light, the stronger its 'antigravity beam' becomes.

    Felber's calculations show how to use the repulsion of a body speeding through space to provide the enormous energy needed to accelerate massive payloads quickly with negligible stress. The new solution of Einstein's field equation shows that the payload would 'fall weightlessly' in an antigravity beam even as it was accelerated close to the speed of light.

    Accelerating a 1-ton payload to 90 percent of the speed of light requires an energy of at least 30 billion tons of TNT. In the 'antigravity beam' of a speeding star, a payload would draw its energy from the antigravity force of the much more massive star. In effect, the payload would be hitching a ride on a star.

    "Based on this research, I expect a mission to accelerate a massive payload to a 'good fraction of light speed' will be launched before the end of this century," said Dr. Felber. "These antigravity solutions of Einstein's theory can change our view of our ability to travel to the far reaches of our universe."

    More immediately, Felber's new solution can be used to test Einstein's theory of gravity at low cost in a storage-ring laboratory facility by detecting antigravity in the unexplored regime of near-speed-of-light velocities.

    During his 30-year career, Dr. Felber has led physics research and development programs for the Army, Navy, Air Force, and Marine Corps, the Defense Advanced Research Projects Agency, the Defense Threat Reduction Agency, the Department of Energy and Department of Transportation, the National Institute of Justice, National Institutes of Health, and national laboratories. Dr. Felber is Vice President and Co-founder of Starmark.

    ReplyDelete
  21. Of course that Mashhoon is referencing Felber's papers, after all, they all believe the same nonsense:

    20. F.S. Felber, gr-qc/0505098; gr-qc/0505099.

    ReplyDelete
  22. It's probably not the case. Here's an interesting comment about Felber (Mashhoon is also mentioned) on the talk page of WP's article "Mathematics of general relativity":

    Felber vandal

    P.S. By Physorg standards even Amrit Sorli is a scientist. LOL

    ReplyDelete
  23. Io, the Physorg article mentions "Dr. Eric Davis, Institute for Advanced Studies at Austin and STAIF peer reviewer of Felber's work". Guess where he hangs out? At Lifeboart Foundation, just like Otto Rössler! HAHAHAHAHA!

    The Lifeboat Foundation page links to this article on Space.com: Research Warps into Hyperdrive. The whole mistake has gained more traction than I imagined.

    ReplyDelete
  24. Shrink's "Felber vandal" link explains the situation well:

    "On February 11, 2006, noted physicist Dr. Franklin Felber announced a new exact solution to the Einstein field equations. His new solution takes into account the gravitational field of a mass moving close to the speed of light, which has never been done before. His research shows that a mass moving faster than 57.7% of the speed of light (approximately 1.731x108m / s) will generate a narrow antigravity beam in front of it, thereby gravitationally repelling other masses lying in its immediate path. The greater the velocity of the mass, the stronger the force of the beam. Dr. Felber believes that his new solution can revolutionize space travel, predicting the possibility of a payload to be transported at a sufficient percentage of the speed of light by the end of the century.... Exotic propulsion is a fringe subject which has numerous very enthusiastic fans. I would caution them against letting their hopes overwhelm their critical judgment..."

    ReplyDelete
  25. Now, that Io confirmed Mashhoon is referencing Felber also in the IJMPD version of his article, I urge Felber to submit his "anti-gravity" papers to IJMPD. I'm sure the referees will find them suitable for publication. LOL

    ReplyDelete
  26. BTW: There's another comment by the "Felber vandal" author regarding Felber/Mashhoon here:

    http://en.wikipedia.org/wiki/Talk%3AAnti-gravity/Archive_1#More_Felber_material

    This part is interesting:

    Felber's second eprint is mentioned by Mashhoon without any comments yay or nay. To find out what leaders think, one would probably have to know physicists like Mashhoon, Jantzen, 't Hooft, Aichelburg who have published on ultraboosts and GEM. I don't know them, but 't Hooft has not been shy in calling a crank a crank in the past.

    It sounds like he's willing to give credit to Felber just because Mashhoon is referencing to him.

    ReplyDelete
  27. But afterwards he gives a clear opinion of Felber's work:

    Since WP is an encyclopedia, I think the best course for the nonce is to continue to remove these wildly overblown claims (no doubt there will be more) and to ask our Felber fan(s) to take it to the talk page. Until such time as Felber publishes in respectable journals like PRD, CQG, GRG rather than Gallilean Electrodynamics or other cranky "journals" and until other physicists begin to publish follow-up work in those journals, Felber's claims should be regarded as fringe and illucid at best (to adopt the terminology of Crankdot).

    ReplyDelete
  28. ???

    [Fel05] p.2
    "[...]S_μν = u_μ . u_ν - c².η_μν/2 is a source tensor with pressure and inner energy neglected[...]"

    Meaning?
    0 ~ S_00 ~ S_11 ~ S_22 ~ S_33?

    So - why first subtracting a purely diagonal tensor (λ.η_μν) and then rounding off the diagonal?



    [Fel05] F. S. Felber. Weak ’antigravity’ fields in general relativity. 2005.

    ReplyDelete
  29. Anonymous from August 20, 2011 7:34 PM said:
    "The sentence is crackpot in ANY interpretation..."

    Boy, I wonder why the Comment was rejected? Instead it is now posted anonymously on an unrelated blog, pointing out mistakes with phrases like "the sentence is crackpot"...truly the epitome of professionalism.

    Dare I ask why this was not submitted on the arXiv, where everyone will read it? Oh, maybe it was rejected there too. Sounds to me this blog is now becoming a mouthpiece of bad science.

    Finally, I read the posted PDF above, there are number of typographical (to give the benefit of the doubt) errors that make it a non-sequitur. I would have rejected it too. This is not say who is right or wrong here, but the Comment posted above in this shape is not publishable, in my honest professional opinion.

    ReplyDelete
  30. Sorry Anonymous 11:42, Google's automatic spam filter (which cannot be turned off) held up your comment and I had to release it.

    The author of the rebuttal can answer for himself, but regarding the suggestion to submit it to arXiv, it seems reasonable to me that a response to an article published in IJMPD should also be published in IJMPD whether it appears in the arXiv or not.

    By all means point out the errors in the rebuttal PDF! Fair is fair. Thank you very much for contributing to this discussion.

    ReplyDelete
  31. So, Anonymous, you're not convinced who is right or wrong, but still you would reject the rebuttal (presumably due to typographical errors)? In my opinion that's a typical straw man argument - an example of bad logic.

    ReplyDelete
  32. To say that something is poorly written, hard to understand and therefore should not be published as is, is a "straw man argument - an example of bad logic."? You learn something new on the internets every day...

    List of the unclear, potentially wrong, maybe typographical issues:
    1. " Theproper speed for a test particle dropped from infinity is derived by integrating (3):" Ok, but then (3) follows, is this supposed to say (2)? Integrating (2) once does not yield (3). Something's missing here.

    2. There should be an explanation of what is the meaning of the changing sign of the coordinate quantities. It is not sufficient to say that they have no physical meaning, ergo the paper is wrong. The end. It must be established what is really occurring. Mashhoon attempts to, maybe he is wrong, the Comment paper sheds no light on this whatsoever, beyond saying "my equation is more right than yours."

    On the basis of the above issues, without a thorough major revision the Comment is not suitable for publication.

    It would appear "shrink" has a large axe to grind with Mashhoon ready to throw an established scientist under the bus, accept absurd "this is crank" arguments about mathematical equations and redefine the rules of logic as they apply to my previous post here

    ReplyDelete
  33. Thanks for defending Mashhoon! Shrink or the rebutter can answer.

    ReplyDelete
  34. Anonymous, I'll wait for the answer from the rebutter.

    Regarding my comment: I still think that someone who is not convinced "who is right or wrong" and would reject a rebuttal due to (previously unspecified) typographical errors (now listed as: "unclear, potentially wrong, maybe typographical issues") is attacking a straw man. Accepting such a flabby argument, not to mention superficial claims (attacking an established scientist, redefining rules of logic), is no less absurd than a "this is crank"
    claim.

    ReplyDelete
  35. BTW, Anonymous: I have no personal or professional disputes or ulterior motives (if this is what you implied with the phrase: "'shrink' has a large axe to grind with Mashhoon/.../") with anyone mentioned on this blog.

    ReplyDelete
  36. 1. Integrating (3) means exactly what it says, i.e. integrating the expression (3). Why do you have so much difficulty with a trivial thing like this? This is textbook stuff.

    2. The Mashhoon paper is wrong because Mashhoon uses coordinate acceleration in order to explain reversal of gravitational force. Coordinate acceleration is MEANINGLESS. Why do you have so much difficulty grasping this simple concept?

    Based on your difficulty in grasping such basic concepts, you are hardly in any position to judge.

    ReplyDelete
  37. A)Io said..."1. Integrating (3)"

    "(3)" in which paper, pls.?

    ---

    B) Jason said on August 20, 2011 7:11 PM

    "In the arXiv version I embedded, the quote comes just after equation 18. The sentence immediately after it is "These results are valid in the linear approximation for the gravitational field under consideration here." [...]"


    Anonymous said on August 20, 2011 7:34 PM
    "The sentence is crackpot in ANY interpretation [...]"

    Aside from the fact that a sentence can never be a crackpot; it appears more likely that is simply a typo in [Mas05].

    Up to eq(15), the expressions are GravitoElectroMagnetic; with the preconditions set around eq(17) and eq(18) the approximations eq(8)

    Φ ~ GM/r, A_ ~ G/c . (J_ cross x_)/r³

    are applied, making eq(17), eq(18) purely gravitational/mechnical. But of course they still result from an GravitoElectroMagnetic ansatz, so I'd assume that

    "These results are valid in the linear approximation for the gravitational field under consideration here."

    should instead read

    "These results are valid in the linear approximation for the GEM field under consideration here."

    An overall DE-celerating overall force would not be THAT extraordinary; pls think about UHECR imping on a neutron star and radiating off surplus energy by cyclotron loss.

    With kind regards,

    Solkar


    [Mas05] Bahram Mashhoon. Beyond Gravitoelectromagnetism: Critical Speed in Gravitational Motion. Int. J. Mod. Phys., D14:2025–2037, 2005.
    http://arxiv.org/abs/astro-ph/0510002

    ReplyDelete
  38. Same for the preceding sentence ending
    "[..] the gravitational attraction turns to repulsion.",

    of course.

    Me guessing only, no warranty implied nor expressed. ;)

    ReplyDelete
  39. The gravitational force cannot be "decelerating" , nor can it reverse sign, as claimed by Mashhoon.
    He's looking at coordinate acceleration, instead of looking at proper acceleration. Basic error.

    ReplyDelete
  40. Io, does your pointing device have a "wheel"?
    Why don't you use it to scroll upwards?

    ReplyDelete
  41. Solkar, the sentence: "Integrating (3) means exactly what it says, i.e. integrating the expression (3)." refers to the rebuttal.

    ReplyDelete
  42. Thx, shrink, but which "rebuttal"?
    What about a title, or a doi?

    (I'm not using facebook so I can't sign in to scribd.)

    ReplyDelete
  43. Use the scroll wheel all the way to the top of this thread.

    ReplyDelete
  44. From more scrolling one could even learn that titles and scribd-labels at do not necessarily match, given one would not know that already. :D

    So again - I'd like to know what the title of that "rebuttal" is.

    I'm not using facebook so I can't sign in to scribd to look for myself. (I somehow think I already mentioned that right above...)

    ReplyDelete
  45. Hmmm, Solkar, you don't need to sign into scribd to see/read the rebuttal (which you can see/read already in this Jason's post at the top):

    http://www.scribd.com/doc/62154141/Rebuttal-to-Mashhoon

    ReplyDelete
  46. Is it too much effort just to reference that paper the usual way or why are we discussing this?

    There are just white sheets displayed on the scribd site in my browser; no content. Why I else would I complain?

    And please, guys, starting don't telling me now about browser-upgrades or stuff like that.

    ReplyDelete
  47. Well, Solkar, it's quite difficult to deduce from your comments that you can't see the document. I don't know what's the cause for that problem and what's the usual way to reference the papers (maybe you're not aware that the rebuttal hasn't been published in any fashion yet, except on this blog). Anyway, Jason decided to reference documents he possess through scribd and if you are not able to see them, I suggest that you ask Jason to send you a copy/copies through email.

    ReplyDelete
  48. Jason, please unstick my comment from the spam filter. :)

    ReplyDelete
  49. I have emailed Solkar the papers and unstuck Shrink's comment. Sorry for the delay.

    ReplyDelete
  50. Thank you, Jason.

    At first glance it's obvious that in [NNXX] a vacuum-solution (T_mu_nu = 0), namely the Schwarzschild-Solution, is used for the ansatz, whereas in [Mas05] quantities are taken from a non-vanishing T_mu_nu; thus it wouldn't be a surprise if both both papers arrived at DIFFERENT figures.

    The remarkable thing is, that the very same velocity 1/sqrt(3) is gathered from both
    - a calc rightfully marked physically meaningless (given [NNXX] calcs were accurate, what I've not checked yet)
    - and, from a DIFFERENT approach(!) in [Mas05]

    Of course, that match of figures is hardly just coincidence, but I find it premature claiming having fund a "rebuttal" just because one has found the same figure from unphysical modeling (ex falso quodlibet).

    It could however, very well be that the clue actually lies in the preconditions set around [Mas05]/eq(8), if they were e.g, by any yet hidden means, inducing a function dt(dτ).

    But that would, of course, still not give a justification for Mashhoon changing notion from "GEM" to (purely) gravitational below his eq(18); pls see above my post of September 9, 2011 10:06 AM for details (but pls scratch "cyclotron loss" and put "synchrotron loss" - my mistake, sorry).

    Furthermore, if, as usual, G, E and M are taken into account, one arrives at the well-known effect of synchrotron loss; there is a case-study for UHECR impinging neutron stars in Appendix G of [GM08].

    On the other hand - "synchrotron loss" is neither overly thrilling nor new by any means - so if that was the effect Mashhoon wanted to demonstrate - what'd by the "magic" of his paper?


    Regards,

    S.



    [GM08] Steven B. Giddings and Michelangelo L. Mangano. Astrophysical implications of hypothetical stable TeV- scale black holes. Phys. Rev., D78:035009, 2008.
    [Mas05] Bahram Mashhoon. Beyond Gravitoelectromagnetism: Critical Speed in Gravitational Motion. Int. J. Mod. Phys., D14:2025–2037, 2005.
    [NNXX]"A rebuttal to a deeply flawed paper" PACS: 03.30.+p, 52.20.Dq, 52.70.Nc; reproduced at http://www.scribd.com/doc/62154141/Rebuttal-to-Mashhoon

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  51. Mashhoon wanted to demonstrate gravitational force "reversal" at the "critical" speed. A total nonsense, compounded by the dishonesty and ineptitude of the IJMPD editors who refuse to publish the rebuttal.

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  52. Excerpt from the abstract of [Mas05]:

    "[...]Working within the framework of gravitoelectromagnetism, the implications of the existence of a critical speed are explored. The results are expected to be significant for high energy astrophysics."

    And for considering [NNXX] a "rebuttal" it needs more than the author claiming it was.

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  53. What else do you want except the fact that Mashhoon claims "reversal of gravitational force"? Isn't that stupid enough?

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  54. Simply claiming sth was "stupid" or "crackpot" is not exactly scientific method.

    Let alone that Mashhoons paper is far from sampling stupidity; its hypothesis may well be wrong, but it's deft'ly not "stupid" by any means.

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  55. The point that you keep missing is that the main claim of the paper is the "discovery" of the "critical" speed v_c where the gravitational force is "reversed". This is precisely what is refuted with mathematical precision in the rebuttal. As such, the rebuttal is ...a bona fide rebuttal.
    The other part that you keep missing is that this thread is less about Mashhoon's mistake and more about the dishonesty of the IJMPD editors. The editors have a history of publishing fringe stuff and refusing to correct or retract. See the other thread on El-Naschie.

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  56. Io, repeating your pov does not substantiate it.

    It's quite obvious that you try to evade discussing the physical and logical reasoning I presented above.

    Better you first make yourself familiar with

    - what Gravitoelectromagnetism is good for from a modern, GR-based perspective
    - the meaning of "vacuum solutions"
    - the difference between Schwarzschild- and Kerr-solutions
    - and, foremost, what a "rebuttal" is,

    PRIOR to calling research about gravity "stupid".

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  57. You didn't provide any physical and logical reasoning other than the fact that you fail to notice that Mashhoon claims to have discovered a "critical" speed v_c where the gravitational force is "reversed". Read the Mashhoon paper abstract. Do you still think that his claim is right?

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  58. What in :

    "A null ray approaching a distant astronomical source appears to slow down, while amassive particle speeds up in accordance with Newtonian gravitation. The integration of these apparently incompatible aspects of motion in general relativity is due to the existence of a critical speed. Dynamics of particles moving faster than the critical speed could then be contrary to Newtonian expectations."

    do you agree with?

    On a different note, don't talk down to me, I understand all the concepts (most probably, better than you do).

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  59. Even the opening sentence in the abstract is downright silly and demonstrates Mashhoon's misconceptions:

    "A null ray approaching a distant astronomical source appears to slow down"

    Of course, Mashhoon is (again) basing his statements on COORDINATE (rather than proper) speed (of light):

    c_r=c(1-r_s/r)

    Coordinate speed/acceleration is irrelevant. You open your paper with an abstract that demonstrates that you don't know this, you discredit everything that follows.
    As an aside, Mashhoon retreads another paper, by Blinnikov and Okum that contains the same exact errors.

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  60. Selective reading, e.g. first skipping both "distant" and "appears" from this sentence

    "A null ray approaching a distant astronomical source appears to slow down"

    and then interpreting it according to personal liking, is not conforming with scientific method.

    Taking personal opinion about a theory as a measure is also not conforming with scientific method; experiments are.

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  61. Speaking of selective reading, I notice that you did not answer the other two challenges.

    Mashhoon has no experiment, just idle and incorrect speculation. You should know better.

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  62. Io: "Speaking of selective reading, I notice that you did not answer the other two challenges."

    Precisely, indeed "selective reading" on your behalf.
    May I provide a recap for your convenience:

    Io: "Do you still think that his claim is right?"
    Io: "What in [...] do you agree with?

    Solkar: "Taking personal opinion about a theory as a measure is also not conforming with scientific method [...]"

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  63. So, you have no answer, just blather. Figures....

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  64. Hi
    I apologise for not having read all comments. I just wish to make the following point: repulsion for a falling mass is a coordinate effect due to the utilisation of coordinate time, rather than proper time. Therefore, repulsive gravity is not a physical concept. Nevertheless, it is an observable effect for a observer. A particle slows down and it never crosses the horizon for a far observer, where it does cross 2M for an observer on the particle. Two more things: there are two kinds of critical velocities c/sqrt(2) and c/sqrt(3) depending whether one uses proper or coordinate length, respectively. Finally, all this stuff was discovered by Johannes Droste in 1915-1916. Sometimes people "rediscover" the repulsion effect because they ignore previous literature.

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