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Experimental proof of Mach's principle?

  1. Feb 19, 2004 #1

    TeV

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    Hi All,
    Probably some of you have seen papers relating Woodward research of the origin of Gravity and Mach's principle.
    Anybody knows what became of all that?The proposed experiment isn't extra difficult for conducting today ,but as far as I know he (Wooodward) had problems with sensitive transducer and other equipment at time.
    Here are some links:
    http://chaos.fullerton.edu/~jimw/nasa-pap
    http://www.grc.nasa.gov/www/bpp/pdf/Cramer-JPC.pdf
    http://chaos.fullerton.edu/~jimw/kill-time/
    http://arxiv.org/ftp/gr-gc/papers/0102/0102002.pdf
     
  2. jcsd
  3. Feb 19, 2004 #2

    turin

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    I read the abstracts, and they seem farfetched. I don't understand how Mach's principle has anything to do with spontaneous manifestation of negative mass. Also, I interpretted (the abstract was written almost equivocally) one of the abstracts to say that past and future are subjective domains of time in relativity. I didn't read through the papers, but, after reading the abstracts, I don't think I'll spend time doing so (that's what abstracts are for, right?).
     
  4. Feb 20, 2004 #3

    TeV

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    I read other Woodward's papers in "Foundations of Physics Letters" and couldn't find basic flaws in his equations.
    The papers in " F. of Phys. Lett." are mostly analitical and have much more details than internet abstracts.
    However something seems fishy to me with final conclusion.
    At least as concerns amount of the measurable effect and introducing sort of longitudal and transfersal mass.
    One way or another there is proposed experiment I would like to know the result of.
     
  5. Feb 20, 2004 #4

    turin

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    Has it been performed, or are we still waiting (or being disappointed by "technical difficulties")?
     
  6. Feb 20, 2004 #5

    TeV

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    Don't know.
    Since NASA got interested in checking whole this thing I assume there shouldn't be "technical difficulties" any more.
    It is known that Einstein accepted Mach's principle apriori.
    But didn't make himself clear of various interpretation of the same.
    Woodward used Sciama interpretation in frame GR.
    Inertia:
    a)local gravity effect
    or
    b)the consequence of radiation force of the whole universe with respect to accelerated object?That's the basic question.
     
  7. Feb 22, 2004 #6
    Thanks for bringing this very interesting topic up, TEV.

    Several years ago I read Woodward's reports ('92, '96). In it he discussed these "transient mass fluctuations", and related it to Machian views, along with the theoretical predictions. I consider it very interesting stuff.

    He did put together experimantal apparatus (a circuit of piezo- crystals & capacitors that oscillated) and which he DID produce positive results,(i.e., reduction in average mass) at a certain frequency.

    Later it was show that the predictions of the effect were incorrect due to his narrow use of the force equation, namely:
    F = m(dv)/dt

    In actuality, the more general eqn. must involve the product derivative: F = d(mv)/dt = m(dv)/dt + v(dm)/dt

    In the exper. situation Woodward described, the 2nd term (which he left out) actually nullifies the 1st term so that there is NO average force change; at least according to a OAk Ridge & DOE report: See here: http://www.ornl.gov/~webworks/cppr/y2001/pres/111404.pdf
    They also pointed out other inconsistencies (somewhat involved which I didn't pursue).

    So how did the anomalous force appear in Woodward experimental results?:

    According to the same report and possibly one you sited, it was due to thermal changes in the piezo-crystal which altered the momentum.

    I think in your report above, there was the suggestion of leaving off the piezos and measuring the change in the capacitors directly.

    Creator:smile:
     
    Last edited: Feb 22, 2004
  8. Feb 23, 2004 #7

    TeV

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    Creator,
    Thank you for reply and providing the link.
    Of course ,I was aware that measurable effect can not be detected by simple experimental equipment Woodward proposed since (althought small) it must be (if exist) even way more smaller.
    But I couldn't find basic error that there is no effect at all if Sciama was right.
    I was very suspicious also becouse woodward tryed to measure small effect while neglecting a small contributor in the equation.
    However,point 6.2 that reactional force must be positive gradient of a potential in G fields doesn't hold a water.And this is where he makes mistake.I didn't spot that in my first reading of Woodward paper.
     
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