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Scientists attempt to measure speed of gravity
spaceflightnow.com ^ | 5 SEP 02 | staff

Posted on 09/05/2002 9:08:22 AM PDT by RightWhale

Scientists attempt to measure speed of gravity

UNIVERSITY OF MISSOURI NEWS RELEASE

Posted: September 4, 2002

Ever since Albert Einstein proposed the general theory of relativity in 1916, physicists worldwide have tested the theory's underlying principles. Whil some principles - such as the speed of light is a constant - have been proven, others have enot. Now, through a combination of modern technology, the alignment of a unique group of celestial bodies on Sept. 8, and an experiment conceived by a University of Missouri-Columbia physicist, one more of those principles might soon be proven.

"According to Einstein's theory, the speed of gravity is assumed to be equal to the speed of light," said Sergei Kopeikin, MU associate professor of physics and astronomy. "While there is indirect evidence this is true, the speed has never been measured directly, and that's what we're attempting to do in an experiment that will not be possible again for another decade."

The experiment will involve precisely measuring the angular distances between several quasars, celestial objects in distant galaxies that resemble stars. On Sept. 8, Jupiter will pass very close to the primary quasar. When it does, its gravity will cause the quasar's position in the sky to shift by a distance that depends on the speed of gravity. Kopeikin and Ed Fomalont, a radio astronomer with the National Science Foundation's National Radio Astronomy Observatory (NRAO), will use an observational technique they developed to compare the position of the primary quasar to the position of other quasars unaffected by Jupiter. Using their data, they hope to confirm the accuracy of Einstein's theory further.

Measurements will be made using the NRAO's Very Long Baseline Array (VLBA), a series of 10, 25-meter radio telescopes located from the Virgin Islands to Hawaii, and the 100-meter radio telescope in Effelsberg, Germany, which is operated by the Max Planck Institute for Radio Astronomy. "Results from recent VLBA test observations indicate we can reach the accuracy necessary to determine the speed of gravity if the experiment goes well," Fomalont said.

"Japanese and NASA scientists also will conduct the experiment independently using other telescopes around the world, so we'll be able to compare our findings," Kopeikin said. "We believe the general theory of relativity is correct and that the speed of gravity is equal to the speed of light."

"The techniques we've employed for this experiment can also be used to more precisely determine the position of other objects in space," Fomalont said. "With more exact positioning of satellites, we could improve telecommunications. Unmanned space navigation could also be improved, allowing us to explore the solar system more deliberately."

The scientists said final results from the experiment should be available in mid-November.


TOPICS: Culture/Society; Extended News; Foreign Affairs
KEYWORDS: einsteinrelativity; gravity; physics; realscience; speedoflight
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To: Nick Danger
if they run into anybody doing that, he would advise against messing with them.

Lol good sugestion

101 posted on 09/05/2002 10:58:37 PM PDT by ATOMIC_PUNK
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To: RightWhale
Everyone knows that gravity is light turned inside out....
102 posted on 09/05/2002 11:01:25 PM PDT by freebilly
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To: RightWhale
Sorry to get off-track, but does relativity only apply in a vacuum?

If light is slowed by the medium (enough?), then its relative velocity starts(?) to depend on the observer's speed relative to the medium, or what?
103 posted on 09/05/2002 11:05:06 PM PDT by apochromat
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To: RightWhale
"According to Einstein's theory, the speed of gravity is assumed to be equal to the speed of light ," said Sergei Kopeikin, MU associate professor of physics and astronomy. "While there is indirect evidence this is true, the speed has never been measured directly, and that's what we're attempting to do in an experiment that will not be possible again for another decade."

You gotta be kidding? As I've read it, the fact that gravity propagates instantaneously is well known and has been for some time.

Apparently that caused a few problems for Albert Einstein, but he has bigger problems than that at present.

Einstein was trying to use relativistic time to account for the fact that light does not obey the ordinary additive laws for velocities. This was based on what he called "thought experiments", such as the mirror-clock experiment, rather than upon anything resembling real evidence or real experiments. Thought experiments, it turns out, are not a terribly good basis for physics. Moreover, the basic approach is unsound. Louis Carrol Epstein ("Relativity Envisioned"), uses the following analogy: a carpenter with a house in which everything worked flawlessly other than one door which bound, would usually plane the door until it worked. He COULD, however, purchase a couple of hundred jacks and jack the foundation of the house until the one door worked, and then try to somehow or other make every other door and window in the house work again... Light is the one door in the analogy; distance, time, mass etc., i.e. everything else in the house of physics are the other doors and windows. Epstein assumes that relativity is the one case you will ever find in which that sort of approach is the correct one, nonetheless, common sense tells us it isn't terribly likely.

It turns out there is another way in which one could account for light not obeying additive laws, and that this other way is the correct one. That is to assume that light simply does not have a velocity; that it is an instantaneous force between two points, and that the thing we call the "velocity of light" is the rate of accumulation of some secondary effect.

The story on this one lives HERE

The basic Ralph Sansbury experiment amounts to a 1990s version of the Michelson/Moreley experiment using lasers and nanosecond gates, which Michelson and Moreley did not have. Wallace Thornhill, an Australian physicist, describes it:



>I mentioned a few weeks ago that an epoch making experiment had been
>performed in the realm of fundamental physics which had great
>importance for Velikovskian style catastrophism (and just about
>everything else for that matter). The experiment, performed by Ralph
>Sansbury, is amazingly simple but has amazing consequences.
>
>Sansbury is a quiet spoken physicist from Connecticut.  He is
>associated with the Classical Physics Institute, or CP Institute, of
>New York which publishes the Journal of Classical Physics. In the
>Notes to Contributors we find the focus of the journal: "Marinov's
>experiment, Bell's theorem, and similar works reveal increasing
>discontent with the dogmas of modern physics. Some physicists
>postulate that blackbody radiation, atomic spectra, nuclear reactions,
>electron diffraction, the speed of light and all other phenomena which
>Quantum Wave Mechanics and Relativity were designed to explain will
>require different explanations. It is the viewpoint of this journal
>that the new explanations probably will be consistent with
>Aristotelian logic and Newtonian or Galilean mechanics." Volume 1,
>Part 1, in January 1982 was devoted to an article titled "Electron
>Structure", by Ralph Sansbury. The title itself should raise
>physicist's eyebrows since electrons are considered to have no
>structure. They are treated as being indivisible, along with quarks.
>
>The fallout from Sansbury's idea, if proven, is prodigious. To begin,
>for the first time we have a truly unifying theory where both
>magnetism and gravity become a derived form of instantaneous
>electrostatic force. The Lorentz contraction-dilation of space time
>and mass is unnecessary. Electromagnetic radiation becomes the
>cumulative effect of instantaneous electrostatic forces at a distance
>and the wave/particle (photon) duality disappears. Discontinuous
>absorption/emission of energy in quanta by atoms becomes a continuous
>process. And there is more.
>
>Sansbury's was a thousand dollar experiment using 10 nanosecond long
>pulses of laser light, one pulse every 400 nsec. At some distance from
>the laser was a photodiode detector. But in the light path, directly
>in front of the detector was a high speed electronic shutter (known as
>a Pockel cell) which could be switched to allow the laser light
>through to the detector, or stop it.
>
>Now, light is considered to travel as a wavefront or photon at the
>speed of light. Viewed this way, it covers a distance of about 1 foot
>per nanosecond. So the laser could be regarded as sending out 10ft
>long bursts of light every 400ft, at the speed of light. The
>experiment simply kept the Pockel cell shutter closed during the 400ft
>of no light and opened to allow the 10ft burst through to the detector.
>
>What happened?
>
>The detector saw nothing!!!
>
>It is as if a gun were fired at a target and for the time of flight of
>the bullet a shield were placed over the target. At the last moment,
>the shield is pulled away - and the bullet has disappeared; the target
>is untouched!
>
>What does it mean?
>
>Only that Maxwell's theory of the propagation of electromagnetic waves
>is wrong! Only that Einstein's Special theory of relativity (which was
>to reconcile Maxwell's theory with simple kinematics) is wrong! Only
>that, as a result, the interpretation of most of modern physics is
>wrong!
>
>As another classical physicist using a theoretical approach to the
>same problem succinctly put it:
>
>"... there emerges the outline of an alternative "relativistic"
>physics, quite distinct from that of Maxwell-Einstein, fully as well
>confirmed by the limited observations available to date, and differing
>from it not only in innumerable testable ways but also in basic
>physical concepts and even in definitional or ethnical (sic) premises
>as to the nature of physics. Thus a death struggle is joined that must
>result in the destruction of one world-system or the other: Either
>light is complicated and matter simple, as I think, or matter is
>complicated and light simple, as Einstein thought. I have shown here
>that some elegant mathematics can be put behind my view. It has long
>been known that inordinate amounts of elegant mathematics can be put
>behind Einstein's. Surely the time fast approaches to stop listening
>to mathematical amplifications of our own internal voices and to go
>into the laboratory and listen to what nature has to say." -
>Modifications of Maxwell's Equations, T E Phipps, The Classical
>Journal of Physics, Vol 2, 1, Jan 1983, p. 21.
>
>Ralph Sansbury has now done precisely that!
>
>In simple terms, Sansbury gives the electron a structure by proposing
>a number of charged particles (he calls subtrons) orbiting within the
>classical radius of an electron. A simple calculation gives the
>surprising result that these subtrons are moving at a speed of 2.5
>million light years per second! That is, they could theoretically
>cover the distance from Earth to the far side of the Andromeda galaxy
>in one second. This gives some meaning to the term 'instantaneous
>action at a distance'. (Note that this is a requirement for any new
>theory of gravity). (Also I have always considered it evidence of
>peculiar naivety or arrogance on the part of scientists, such as
>Sagan, who search for extra-terrestrial intelligence (SETI) by using
>radio signals. What superior intelligence would use such a slow, and
>therefore useless, interstellar signalling system?) Such near infinite
>speed requires that there can be no mass increase with velocity. The
>speed of light is not a speed barrier. All of the experiments which
>seem to support Einstein's notion are interpreted by Sansbury in a
>more common-sense fashion. When an electron or other charged particle
>is accelerated in an electromagnetic field, it is distorted from a
>sphere into an ellipsoid. The more electromagnetic energy applied to
>accelerating the particle, the more energy is absorbed by distortion
>of the particle until, ultimately, at the speed of light, there is an
>expulsion of the subtrons. Under such conditions, the particle only
>APPEARS to be gaining mass.
>
>Notably, in the past few months, scientists in Hamburg using the most
>powerful electron microscope have found on about a dozen occasions out
>of 10 million trials, relativistic electrons recoiled more violently
>off protons than had ever been seen before. This may turn out to be
>direct experimental proof of Sansbury's model of the electron having
>structure.
>
>To return to the experiment involving a "chopped" light beam: One of
>the major requirements of the new theory is instantaneous
>electrostatic forces between subtrons. This forms the basis of a
>radical new view of the basis of electromagnetic radiation which is
>now the subject of stunning experimental confirmation. In Sansbury's
>view, a signal from a light source is received instantly by a distant
>detector and the speed of light delay in detecting the signal is due
>to the time taken for the ACCUMULATED RESPONSE of the subtrons in the
>detector to result in a threshold signal at the electron level. This
>is totally at variance with orthodox interpretations which would have
>the light travelling as a discrete photon or wave packet at the speed
>of light.
>
>In terms of the gun and target analogy, it is as if particles of the
>bullet are being absorbed by the shield from the instant of firing, so
>that when the shield is pulled aside there is no bullet left to hit
>the target.
>
>It is not possible to overstate the importance of this work because it
>lends direct support to a new model of the electron in particular, and
>matter in general, which EXPLAINS magnetism, gravity and quantum
>effects without any resort to the kind of metaphysics which allows our
>top physicists to think they can see "God" in their equations.  The
>new classical physicists can mix it with the best of them when it
>comes to the mathematics but they are more prepared to "go into the
>laboratory and listen to what nature has to say."
>
>This work is of crucial importance for Velikovskian re-arrangements of
>the solar system in recent times because astronomers have been able to
>say that such scenarios defy the laws of physics - which is true,
>insofar as they know the laws of physics. To discover that gravity is
>a form of charge polarization within the particles that make up the
>atom, rather than a warp in space (whatever the hell that means),
>gives us a simple mechanism by which the solar system can be rapidly
>stabilised after a period of chaotic motion.
>
>There is an impression, as I reread the work of Sansbury and other
>classical physicists, that what we are facing is something like "Back
>to the Future". And like the movie of that name, the possibilities
>that we encounter will seem like science fiction come true. But it is
>well-known that science fiction writers are better at predicting the
>future of science than experts!


Sansbury as I've heard it describes the instantaneous propagation speed of gravity and related phenomena as essentially equivalent to the computed necessary speed of a sub-electron particle which, while not really infinite, would get you from here to one of the near galaxies in a couple of seconds or thereabouts.

104 posted on 09/06/2002 3:14:23 AM PDT by medved
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To: Lonesome in Massachussets
Sure, but what's the speed of dark?

That's what comedian Dennis Miller once asked, isn't it?

I'm no physicist, but it looks to me to be zero. $:-)

105 posted on 09/06/2002 4:59:45 AM PDT by Joe Brower
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To: Southack
So, are you saying that mass only has gravity because it is in motion? If the universe were to stand still then gravity would cease?

Interesting theory, even if you weren't saying that.

Shalom.

106 posted on 09/06/2002 5:46:09 AM PDT by ArGee
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To: john in missouri
Especially if you're a young bachelor guy...

I could make another "especially" but we've had enough Hillary jokes on this thread.

Shalom.

107 posted on 09/06/2002 5:48:12 AM PDT by ArGee
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To: john in missouri
Whatever other points we might disagree upon from time to time here at free republic, I'm sure we can all agree that placing Hillary's butt on Pluto seems to be an excellent idea!

John in Missouri for Director of the NASA Administration in 2002!

Note how I slipped the redundancy in.

Shalom.

108 posted on 09/06/2002 5:49:21 AM PDT by ArGee
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Comment #109 Removed by Moderator

To: Southack
Hey Southack, check out discussion of gravitons here...

" The graviton is the exchange particle for the gravity force. Although it has not been directly observed, a number of its properties can be implied from the nature of the force. Since gravity is an inverse square force of apparently infinite range, it can be implied that the rest mass of the graviton is zero."

110 posted on 09/06/2002 7:17:07 AM PDT by maxwell
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To: maxwell; ArGee; Physicist
OK, Physicist didn't like my theory, to say the least, so here is my humble follow up:

All four of the fundamental forces involve the exchange of one or more wave-like particles.
Strong Force -> pion (and others)
Weak Force -> W and Z
Electromagnetic Force -> photon
Gravity -> graviton

Such exchange forces may be either attractive or repulsive. The maximum range of each exchange force is further dictated by the uncertainty principle. Since the particles involved are created and exist only in the exchange process, they are called "virtual" particles.

If a force involves the exchange of a virtual particle, then that particle has to "get back home before it is missed" in the sense that it must fit within the constraints of the uncertainty principle, and a particle of mass m and energy E=MC^2 can be exchanged if it does not go outside the bounds of the uncertainty principle.

The graviton is the exchange particle responsible for force of gravity. Although it has not been directly observed, a number of its properties can be implied from the nature of the force. Since gravity is an inverse square force of apparently infinite range, it can be implied that the rest mass of the graviton is zero.

The photon is the exchange particle responsible for the electromagnetic force. The infinite range of the electromagnetic force is due to the zero rest mass of the photon, but so long as the photon has a non-zero mass (i.e. not at rest), it is capable of deflection by gravity due to its ability to exchange gravitons.

Where it gets interesting, however, is that we know that photons (much less gravitons) are not normally at rest. Moreover, photons that are not at rest will always be affected by the gravity of a large object (and this is proven by observation). This would imply that photons not at rest have mass, except that we know that anything that travels at light speed can not have mass. Thus, one is left to conclude that photons not at rest gain an imaginary or "virtual" mass that can exchange gravitons.

This is experimentally verifiable. Recent experiments have demonstrated that as light slows to near-zero velocity, it is less and less affected by gravity.

Thus: Southack's Theory on the Speed of Gravity
Part Two:
(Virtual Mass of Graviton)
E=MC^2
All mass has energy
Gravity (G) is the energy of a mass, therefore
G=E/M
G=CGp (Southack's Theory on the Speed of Gravity)
Gravity and Light are inter-related due to the virtual mass of gravitons and photons at speed, therefore G=C^2
Gp=C
Gp = Virtual Mass of Graviton / Virtual Mass of Photon
Virtual Mass of Graviton = C * Virtual Mass of Photon

Part One
(Speed of Gravity)
1. Light has no real mass
2. Photons of light have no real mass at rest.
3. Photons of light not at rest have virtual mass.
4. Non-resting photons emit gravitons, giving light a virtual mass and a real gravity.
5. Gravity can appreciably bend light due to the emission by photons of gravitons.
6. Light does not appreciably bend gravity.
7. Gravity can appreciably bend light because gravitons have much more virtual mass than photons.
8. Gravitons have much more virtual mass than photons because gravitons travel much faster than photons.

Therefore, Gravity is much faster than the speed of Light. The Speed of Gravity (G) can hereby be represented as the speed of light (C) multiplied by the constant Gp. G=CGp. Gp represents the ratio of difference in virtual mass between photons and gravitons. The ratio of this difference in virtual masses is equal to C.

The Speed of Gravity is therefore the speed of light squared (G=C^2), 3.4703029E10 miles per second.

In contrast, Ralph Sansbury describes the near-instantaneous propagation speed of gravity and related phenomena as essentially equivalent to the computed necessary speed of a sub-electron particle. Sansbury says that the electron structure is really a number of charged particles (he calls subtrons) orbiting within the classical radius of an electron. His calculation gives the surprising result that these subtrons are moving at the much faster speed of 2.5 million light years per second (1.4686906E19 miles per second).

111 posted on 09/06/2002 10:44:18 AM PDT by Southack
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To: RightWhale
Bump
112 posted on 09/06/2002 10:45:41 AM PDT by Fiddlstix
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To: ATOMIC_PUNK
the absence of gravity in a vortex

Might you be referring to the difficult vortex theory of gravitation?

113 posted on 09/06/2002 12:06:07 PM PDT by RightWhale
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To: apochromat
does relativity only apply in a vacuum?

Probably not just in a vacuum, but at normal speeds, such as one might find inside a gas, liquid, or solid, the effect of relativity would be small, or in the range where it could be safely ignored. Plasma is nearly a vacuum, so relativity is probably important in that regieme.

114 posted on 09/06/2002 12:10:31 PM PDT by RightWhale
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To: medved
A good measurement ought to settle the issue.
115 posted on 09/06/2002 12:12:07 PM PDT by RightWhale
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To: RightWhale
One potential problem with getting a good measurement is that this particular experiment is looking to find that the speed of gravity is equal to the speed of light, rather than the extraordinarily greater speed that gravity is more likely to be.
116 posted on 09/06/2002 12:28:09 PM PDT by Southack
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To: Southack
It's the perennial problem with designing an experiment. The range of answers has to be anticipated. Remember the Russians missed the Van Allen Belts because the radiation was much stronger than expected and the data was out of range on the high side. For Van Allen it wasn't luck, he didn't know what to expect and so put up a detector that could read way up the scale. If the speed of gravity isn't near what they expect, the experiment won't work right.

If the speed of gravity is actually a few orders of magnitude above the speed of light, think of the possibilities that would open up for remote sensing exploration of the universe. I won't waste bandwidth here speculating on what might result from that outcome.

117 posted on 09/06/2002 12:36:30 PM PDT by RightWhale
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To: RightWhale
Maybe something new has happened which I've never heard about, but my understanding has always been that many experiments have always yeilded the result that gravity was instantaneous within the error bounds of measurement.
118 posted on 09/06/2002 1:08:24 PM PDT by medved
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To: medved
Apaprently the final word hasn't been issued to the rest of the scientific community. Or to any of it. The scientific community will very interested if the speed of propagation of gravity turns out to be different from the speed of propagation of light. There will be so many articles and letters submitted to the scientific journals there will be an ink shortage if they try to print everything.

As a group those scientists are pretty smart. They'll know something revolutionary almost instantly. E-mails alone will clog the bandwidth for hours.

119 posted on 09/06/2002 1:16:36 PM PDT by RightWhale
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To: Southack
Thanks for the heads up! };^D)
120 posted on 09/06/2002 2:09:09 PM PDT by RJayneJ
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