16-November-2007, 08:11 PM
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Junior Member
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Join Date: Jun 2007
Posts: 25
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pushing gravity
[/COLOR] I happen to be fairly well versed in the concept of “pushing gravity”. There is extensive discussion of the subject at Tom VanFlandern’s http://www.metaresearch.org. Also check out Wikipedia’s LeSage’s theory of gravitation. Actually, Newton’s associate, Fatio, probably deserves more credit than LeSage. Paul Schroeder’s “paeps” were called “gravitons” by LeSage; VanFlandern calls them “classical gravitons” (CG’s) to distinguish them from the gravitons of today’s standard model, to which they bear no resemblance, whatever. (I plead ignorance concerning standard model gravitons.)
Einstein assumed that the force vector of gravity should point to where its source mass is now, not to where the source was when light now arriving at the observer left the source. (See Wikipedia Speed of Gravity.) That is the logical equivalent of the force of gravity propagating with infinite speed—though Einstein insisted gravity does not propagate, rather it is a timeless property of the space-time continuum. Pushing-gravity theorists have assigned various finite speeds to gravity; some mainstream scientists claim gravity propagates at c, but to my knowledge, Paul Schroeder is alone in claiming that paeps move at light speed. VanFlandern’s latest estimate is that CG’s have a mean speed of vg > 20 billion c; being a perfect gas, they don’t all move at exactly the same speed. VanFlandern cautions against confusing the speed of gravity force with the speed of gravity waves; he agrees with Einstein that gravity waves propagate at c.
If, indeed, CG’s move faster than 20 billion c, they carry a tremendous amount of energy. If you multiply the CG’s momentum by its speed, it quickly becomes obvious that absorption of CG’s cannot account for gravity; the object would absorb the energy equivalent of its own mass in less than a picosecond. If only scattering of CG’s is involved, there can be no net push. VanFlandern claims that the energy of the few absorbed CG’s is somehow transferred to the many CG’s that are scattered. Victor J. Slabinsky did the math for VanFlandern and concluded that at least 1020 CG’s must be scattered for every one that is absorbed.
I have my own Fractal Foam Model of Universes, in which (pressure) p-waves in the ether fill the role of CG’s, and (sheer) s-waves in the ether are photons. (As J. C. Maxwell said, if there is an ether, it must be a solid in order to transmit transverse waves.) I posted an early version some months ago as my own ATM thread; it died without receiving serious consideration or comment. Since then, I have made major changes to the model. The changes are near the small end of the scale—in the area of particle physics, not astronomy; so I’m not sure if you want them on your website. If the moderators reopen my ATM, I’ll discuss the changes, there. In the mean time, my latest updates can be viewed on my Yahoo!360 blog.
Some comments on Olber’s paradox:
If you assume Hubble’s “constant” is constant (just to simplify the problem), you can easily calculate a distance at which objects are moving away from us at the speed of light; I think that is similar to how BigBangers get the number 13.7 billion light years. The closer you get to that distance, the greater the red shift and the less energy is contained in the light (in the observer’s frame). At even greater distances, objects recede faster than light. So even if the universe is infinite, only a finite portion of it can ever be seen. (Note: Faster than light velocities do not violate relativity. The 4D space-time of general relativity covertly redefines velocity. The instant the pilot puts the pedal to the metal, the destination may become light years closer than it was the instant before, but the velocity of the destination remains zero. This permits a space ship to reach its destination in less time than it takes for light to get there—without ever moving faster than light. In a 3D version of general relativity, c is the speed limit for two objects passing one another, but there is no speed limit for distant galaxies ahead or behind an accelerating observer.)
Perhaps another clue to keeping the universe cool may be found in the conversion of dark energy to new space. The expansion of space is an infinite heat sink.
Furthermore, Stephen Hawking’s insane ramblings not withstanding, we have no way of knowing what the universe was like 13.7 billion years ago. Shouldn’t we understand gravity before extrapolating Newton’s equations that far into the past? Maybe there were no light sources then in existence whose light could now be reaching us from such a distance.
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