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Is here some Doppler effect for the gravity?

  1. Jan 22, 2012 #1
    Lets say we have some particle A 1m above the ground.
    Let it has velocity v.
    Also lets consider gravitons like the reason/mechanism of the gravitation.
    Let gravitons moves away from the Earth with velocity c.

    Now lets consider the differences between two cases:
    1 when particle A moves down and
    2 when particle A moves up.

    Case 1:
    Particle A moves down and meets 1+v/c times more gravitons per second.
    Also each graviton is stronger 1+v/c times (because of blue shift)
    So the total gravitational force F = F0 * (1+v/c)^2

    Case 2:
    Particle A moves up and meets 1-v/c times less gravitons per second.
    Also each graviton is weaker 1-v/c times (because of red shift)
    So the total gravitational force F = F0 * (1-v/c)^2

    What do you think?
    (Please do not fetter your imagination just with one/single theory of gravity :smile:)
    Last edited: Jan 22, 2012
  2. jcsd
  3. Jan 22, 2012 #2


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    Alvydas, gravitons are hypothetical, not real. The accepted and proven ways to describe gravity are called "The Special Theory of Relativity" and "The General Theory of Relativity". In SR velocities do not add the way you propose, so no doppler. Please check on that.

    As for "fettering my imagination just with one/single theory of gravity": Thank you, but I prefer to put my faith in the gravitational theory that has been proven to be correct by thousands of experiments over nearly100 years since Einstein published them. NEVER has there been evidence or proof that SR or GR is wrong.
  4. Jan 22, 2012 #3


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    As Bobbywhy said, we don't yet know if gravitons exist or not. If they did, they would cause a change in gravity. If gravity is unchanging, no gravitons are required.
  5. Jan 23, 2012 #4
    Ok, lets try to make some calculations.
    I will use reverse version of the scheme I already mentioned,
    because I guess more likely is that gravitons comes from outside and push bodies together (if such gravitons exist).

    So a body moving away from the Sun will be effected by force
    F = F0*(Doppler_coefficient)^2 = G*M/(r^2) * (1 + v/c)^2
    so additional acceleration to word the Sun will be about (when v<<c)

    a = (GM/r^2) * 2v/c

    if v = about 9000 m/s
    a = 8.847496 × 10^-10

    See http://www.google.lt/search?q=1.3271244%2010^20%20%2F%20%283*10^12%29&ie=utf-8&oe=utf-8&aq=t&rls=org.mozilla:en-US:eek:fficial&client=firefox-a&source=hp&channel=np#pq=1.3271244+10^20+%2F+%283*10^12%29&hl=lt&cp=42&gs_id=hg&xhr=t&q=%28+%281.3271244*10^20%29+/+%283*10^12%29^2+%29+*+%282*9000/300000000%29&pf=p&sclient=psy-ab&client=firefox-a&hs=R8Z&rls=org.mozilla:en-US%3Aofficial&channel=np&source=hp&pbx=1&oq=%28+%281.3271244*10^20%29+/+%283*10^12%29^2+%29+*+%282*9000/300000000%29&aq=f&aqi=&aql=&gs_sm=&gs_upl=&bav=on.2,or.r_gc.r_pw.,cf.osb&fp=ba3bb42e57434d56&biw=1406&bih=772
    Now see http://en.wikipedia.org/wiki/Pioneer_anomaly and compare the results.
    I guess Pioneer anomaly is solved :)
  6. Jan 23, 2012 #5


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    You just wrote in post # 4 "I guess the Pioneer anomaly is solved :)"

    You already have written in your opening post "(Please do not fetter your imagination just with one/single theory of gravity smileyface)"

    Has it been your intention all along to try to explain the Pioneer anomaly?

    If yes, then it would have avoided misleading thought experiments and vague inuendos if you had said so in the beginning Opening Post.

    If yes, I suggest you check the Guidlines of this forum. Personal theories are not allowed here.

    There is no empirical evidence (that's what scientists use to prove a hypothesis) yet that gravitons exist, no matter how emotionally attractive they may be.

    If any of my comments are incorrect I invite you to correct them. Thank you for your attention.
  7. Jan 23, 2012 #6
    What personal?
    http://en.wikipedia.org/wiki/Nicolas_Fatio_de_Duillier 1690
    http://en.wikipedia.org/wiki/Georges-Louis_Le_Sage 1724
    Henry Lorentz 1900

    Are they all forbidden now ?

    The fact that they fit to Pioneer anomaly I calculated only this morning.
  8. Jan 23, 2012 #7


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    Alvydas, Please excuse my inappropriate use of the word “personal”. Now that you have finally informed all the readers here on Physics Forums exactly what theories you have been using for the ideas contained in your posts it has become plain that the underlying proposals are not yours personally. Still, you are the person who brought all this here.

    Below please find a few quotations I selected from the below reference:


    “Every Le Sage-type model assumes the existence of a space-filling isotropic flux or radiation of ultra mundane corpuscles with enormous intensity and penetrating capability.”

    Are these particles those that you are referring to as “Gravitons”?

    “Gravitational shielding implies that addition of matter does not result in a direct proportional increase in the gravitational mass. Any form of gravitational shielding would represent a violation of the equivalence principle, and would be inconsistent with the extremely precise null result observed in the Eötvös experiment and its successors — all of which have instead confirmed the precise equivalence of active and passive gravitational mass with inertial mass that was predicted by general relativity.[44]”

    Since this aspect of the theory violates both the equivalence principle and the Eötvös experiment, two of the most tested, verified, and validated phenomena in the history of science, it causes the Sage-type model to collapse and disintegrate.

    “1965 Richard Feynman examined the Fatio/Lesage mechanism, primarily as an example of an attempt to explain a "complicated" physical law (in this case, Newton's inverse-square law of gravity) in terms of simpler primitive operations without the use of complex mathematics, and also as an example of a failed theory. He notes that the mechanism of "bouncing particles" reproduces the inverse-square force law and that "the strangeness of the mathematical relation will be very much reduced", but then notes that the scheme "does not work", because of the drag it predicts would be experienced by moving bodies, "so that is the end of that theory".”

    It seems to me you have either not seen the above quotes or did see them and decided to ignore them. I am hoping other more qualified physicists here will evaluate your proposals and post their comments as well. Everyone has the right to believe anything they choose to. I prefer to put my faith in Feynman and Einstein, but that’s just me.
    Last edited: Jan 23, 2012
  9. Jan 23, 2012 #8

    Vanadium 50

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    The purpose of PF is not to try and explain an anomaly in terms of previously discredited theories.

    If the OP can find a reputable journal that discusses Pioneer in terms of LeSage gravity, the thread can be reopened.
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