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Thread: Discussion: Gravity Moves at the Speed of Light

  1. #1
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    SUMMARY: Theorized by Einstein for almost a century, physicists have found evidence to support the theory that the force of gravity moves at the speed of light. The speed was measured by physicist Sergei Kopeikin by watching how light from a distant quasar was bent by Jupiter's gravity. Variations in how the image of the quasar was bent accounted for this speed of gravity.


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    Gravity moves at the speed of light?!? So does that mean we're all being gravitationally effected by looking up at the night sky and seeing all those magnificent points of light?

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    Quote Originally Posted by Fraser
    SUMMARY: Theorized by Einstein for almost a century, physicists have found evidence to support the theory that the force of gravity moves at the speed of light. The speed was measured by physicist Sergei Kopeikin by watching how light from a distant quasar was bent by Jupiter's gravity. Variations in how the image of the quasar was bent accounted for this speed of gravity.


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    This thread is similar to Speed of Gravity...can of worms by Slywester Kornowski. However, I am quite pleased that this result is in concordance with the results of SN1987a. There the arrival was less than 2 seconds separation after 160,000 years of travel time. Pete

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    Quote Originally Posted by trinitree88
    This thread is similar to Speed of Gravity...can of worms by Slywester Kornowski. However, I am quite pleased that this result is in concordance with the results of SN1987a. There the arrival was less than 2 seconds separation after 160,000 years of travel time. Pete
    How was the gravitational effect of SN1987a measured?

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    Quote Originally Posted by Fraser
    SUMMARY: Theorized by Einstein for almost a century, physicists have found evidence to support the theory that the force of gravity moves at the speed of light. The speed was measured by physicist Sergei Kopeikin by watching how light from a distant quasar was bent by Jupiter's gravity. Variations in how the image of the quasar was bent accounted for this speed of gravity.


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    There has been some controversy about the measurement. I'm not an expert in GR by any stretch of the imagination, but I found his presentation compelling when I attended a colloquium he gave a while back.

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    Interesting article, cheers.

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    Heh, just made a reference to this just the other day here

  8. #8
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    gravitational effect

    Quote Originally Posted by jkmccrann
    How was the gravitational effect of SN1987a measured?
    At the time of SN1987a, the gravity wave detectors were large aluminum cylinders, suspended by wires. Piezoelectric sensors mounted on them searched for a pattern whereby the bar changed dimensions sequentially in two orthogonal directions...signaling a gravitational wave passing. Joseph Weber (Univ. of Maryland) was the American group leader. Rome was a similar set-up. Results were reported at Neutrino 88, the conference at Tufts Univ., Medford, MA by Guido Pizella. You can find him at NASA Astrophysics Database. It was later republished by Larry Sulak et al (head of the IMB neutrino detector)...also in Il Nuovo Cimento C....circa 1993. . confidence level 99.99 %.

    Remember, proponents of the next experimental design...the LIGO, laser interferometric gravitational-wave observatory, are hardly likely to see funding, if the contemporary design is already seeing these effects. So those scientists are going to be particularly doubtful of the legitimacy of the initial detections by bar detectors. As I am not an experimental physicist, I'm not going to get into it in a big way, but in my personal conversation with Professor Sulak, he was, without doubt, sure they(gravitational waves ) had been seen. Pete.

    P.S. My conversation with Prof. Sulak involved the piezoluminescence sometimes seen in salt mines when the lights are out. Shifting salt crystals under stress/strain conditions flash weakly. I was curious if the walls were moving. He commented that the floors of the IMB...once machined flat...seemed to be buckling up. "Do you mean they're moving?" he asked. (salt domes are considered very geologically stable). "Yes, Scientific American ran an article called Salt Tectonics...they move." I replied. He was curious, so a few months later I chased down the article for him, and personally delivered it to Boston Univ. (I had business there also). Prof. Sulak wasn't around that day. Three months later the roof of the IMB fell in......just like inflationary spacetime models of the BB will with the WMAP 2nd year data release. Ciao. Pete
    Last edited by trinitree88; 2005-Dec-13 at 03:30 AM.

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    Very interesting Pete, Cheers. Interesting anecdote regarding the `Salt Tectonics' as well.

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