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TheCow
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Speed of light travel
#5294786 - 02/13/06 01:28 PM (17 years, 11 months ago) |
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http://www.physorg.com/news10789.html
On Tuesday, Feb. 14, noted physicist Dr. Franklin Felber will present his new exact solution of Einstein's 90-year-old gravitational field equation to the Space Technology and Applications International Forum (STAIF) in Albuquerque. The solution is the first that accounts for masses moving near the speed of light.
Felber's antigravity discovery solves the two greatest engineering challenges to space travel near the speed of light: identifying an energy source capable of producing the acceleration; and limiting stresses on humans and equipment during rapid acceleration.
"Dr. Felber's research will revolutionize space flight mechanics by offering an entirely new way to send spacecraft into flight," said Dr. Eric Davis, Institute for Advanced Studies at Austin and STAIF peer reviewer of Felber's work. "His rigorously tested and truly unique thinking has taken us a huge step forward in making near-speed-of-light space travel safe, possible, and much less costly."
The field equation of Einstein's General Theory of Relativity has never before been solved to calculate the gravitational field of a mass moving close to the speed of light. Felber's research shows that any mass moving faster than 57.7 percent of the speed of light will gravitationally repel other masses lying within a narrow 'antigravity beam' in front of it. The closer a mass gets to the speed of light, the stronger its 'antigravity beam' becomes.
Felber's calculations show how to use the repulsion of a body speeding through space to provide the enormous energy needed to accelerate massive payloads quickly with negligible stress. The new solution of Einstein's field equation shows that the payload would 'fall weightlessly' in an antigravity beam even as it was accelerated close to the speed of light.
Accelerating a 1-ton payload to 90 percent of the speed of light requires an energy of at least 30 billion tons of TNT. In the 'antigravity beam' of a speeding star, a payload would draw its energy from the antigravity force of the much more massive star. In effect, the payload would be hitching a ride on a star.
"Based on this research, I expect a mission to accelerate a massive payload to a 'good fraction of light speed' will be launched before the end of this century," said Dr. Felber. "These antigravity solutions of Einstein's theory can change our view of our ability to travel to the far reaches of our universe."
More immediately, Felber's new solution can be used to test Einstein's theory of gravity at low cost in a storage-ring laboratory facility by detecting antigravity in the unexplored regime of near-speed-of-light velocities.
During his 30-year career, Dr. Felber has led physics research and development programs for the Army, Navy, Air Force, and Marine Corps, the Defense Advanced Research Projects Agency, the Defense Threat Reduction Agency, the Department of Energy and Department of Transportation, the National Institute of Justice, National Institutes of Health, and national laboratories. Dr. Felber is Vice President and Co-founder of Starmark.
Source: Starmark
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RuNE
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Re: Speed of light travel [Re: TheCow]
#5298125 - 02/14/06 05:30 AM (17 years, 11 months ago) |
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Uhm.
Cool. 
-------------------- ~Happy sailing~
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TheDudeAbides
Livin Off FrostyBarley Pops andPork Soda


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Re: Speed of light travel [Re: RuNE]
#5299408 - 02/14/06 02:19 PM (17 years, 11 months ago) |
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Finally.
-------------------- outputrotation said: x-com and unsolved mysteries are the only things that have ever made me truly scared
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Ref
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Ive always wanted to live on Uranus.
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Huehuecoyotl
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Re: Speed of light travel [Re: TheCow]
#5305702 - 02/16/06 07:02 AM (17 years, 11 months ago) |
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This article explained nothing. It is bunk.
-------------------- "A warrior is a hunter. He calculates everything. That's control. Once his calculations are over, he acts. He lets go. That's abandon. A warrior is not a leaf at the mercy of the wind. No one can push him; no one can make him do things against himself or against his better judgment. A warrior is tuned to survive, and he survives in the best of all possible fashions." ― Carlos Castaneda
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Seuss
Error: divide byzero


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> This article explained nothing. It is bunk.
What, you don't buy into the 'antigravity beam'?
-------------------- Just another spore in the wind.
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TheCow
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Re: Speed of light travel [Re: Seuss]
#5307163 - 02/16/06 02:05 PM (17 years, 11 months ago) |
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Ha well Im going to wait until he releases the paper so I can view the math. Interesting though.
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Seuss
Error: divide byzero


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Re: Speed of light travel [Re: TheCow]
#5309496 - 02/17/06 04:16 AM (17 years, 11 months ago) |
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> Im going to wait until he releases the paper so I can view the math.
Same reason I didn't comment on the story... however, the word 'beam' sounds very odd in a non-optics related physics paper.
-------------------- Just another spore in the wind.
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ChuangTzu
starvingphysicist



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Re: Speed of light travel [Re: TheCow]
#5310046 - 02/17/06 10:49 AM (17 years, 11 months ago) |
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Quote:
TheCow said: Ha well Im going to wait until he releases the paper so I can view the math.
http://arxiv.org/abs/gr-qc/0505098
Know much field theory?
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Seuss
Error: divide byzero


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Re: Speed of light travel [Re: ChuangTzu]
#5318668 - 02/20/06 04:28 AM (17 years, 11 months ago) |
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> Know much field theory?
Not enough to understand that... at least in the paper they are called fields rather than beams...
> This article explained nothing. It is bunk.
The article is bunk, but the paper is not. The article actually makes the paper sound like pseudo-science, but it most certainly is not. The paper is a bit over my head, but from the parts that I understand, sounds very interesting.
-------------------- Just another spore in the wind.
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RuNE
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Re: Speed of light travel [Re: Seuss]
#5318736 - 02/20/06 05:47 AM (17 years, 11 months ago) |
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Fuck.......
"Set course to Mars, Warp 1" ...aint too far off. 
-------------------- ~Happy sailing~
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Asante
Mage


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Re: Speed of light travel [Re: TheCow]
#5318780 - 02/20/06 06:42 AM (17 years, 11 months ago) |
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It begins..
-------------------- Omnicyclion.org higher knowledge starts here
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Madtowntripper
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Re: Speed of light travel [Re: Asante]
#5319495 - 02/20/06 10:52 AM (17 years, 11 months ago) |
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I should ask one of the Physics prof's around here if they know anything about this, or if this guy is a total crackpot.
Maybe I'll do that later today after class.
-------------------- After one comes, through contact with it's administrators, no longer to cherish greatly the law as a remedy in abuses, then the bottle becomes a sovereign means of direct action. If you cannot throw it at least you can always drink out of it. - Ernest Hemingway If it is life that you feel you are missing I can tell you where to find it. In the law courts, in business, in government. There is nothing occurring in the streets. Nothing but a dumbshow composed of the helpless and the impotent. -Cormac MacCarthy He who learns must suffer. And even in our sleep pain that cannot forget falls drop by drop upon the heart, and in our own despair, against our will, comes wisdom to us by the awful grace of God. - Aeschylus
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RuNE
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Did you ask?
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TheCow
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Re: Speed of light travel [Re: RuNE]
#5323986 - 02/21/06 12:58 PM (17 years, 11 months ago) |
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Yea I can understand that paper. Its amazing our first order approximations can be that off. I await the other paper however, as that sounds a bit more enticing, at least from the propaghanda.
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outerwave
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Re: Speed of light travel [Re: TheCow]
#5356257 - 03/02/06 03:08 AM (17 years, 10 months ago) |
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well, i studied a bit of partical phys. in a prior life. so:
using the word 'beam' really just concerns a directed field. doesn't even need to be directed energy in the case of a laser or microwave overn or whatever. but say gravity, which as a field an not an energy. there are few concepts to be noted. first, the article mentions it, but it takes exponentially more energy to increase you speed the faster you go. if you are already travelling at 270000 km/second (%90 lightspeed) it takes something like as much fuel/energy to get to %91 percent (%1 faster) as it did to get to %90 in the first place (roughly).
using the word 'beam' is a way of communicating to layman various fields on the subatomic level. we are all familiar with gravity, but there are other forces like 'strong force' and 'weak force' (physicists are not know for creative naming) that are like gravity but hold the little bits together in the universe. interstingly these forces actaully 'work' faster than lightspeed, or instantly. example, if a new planet were to just pop into existence in the solar system, 1 light year away from earth (for example) you would think, since _nothing_ is supposed to go faster than light, it would take one year for the gravitational pull to reach to earth and effect us. when actaully, that 'field' or 'beam' of gravitaional pull INSTANTLY starts pulling on its surroundings, be they 10 feet away or 10 light years away... these forces work around lightspeed and it gets a bit hairy as to how.
ANYWAY, his idea is really nothing new. it would require more energy than can be imagined to pull a 'star trek' and go from 0 to warp speed in 1 second. low and slow is the way to go. if you were to apply a constant force, an engine accelerating at nice and low rate, but constantly, you speed would gradually increase to lightspeed. with constant acceleration, it will take longer and longer to go a few km/h faster the faster you are already travelling. might take 5000 years to get up to speed, and another 5000 to slow down, but it is doable. you really never would 'cruise' at a speed, you'd speed up and up and up, then start breaking halfway to your destination. he is proposing using 'free' (not fuel required) energy from fields of celestial bodies to slowly and steadily get up to speed. still will take a human lifetime to get even a fraction of the way there. same idea is used on 'solar wind' conecpts. letting the force of photons (light) and such emmitting from the sun catch on a giant sail, and slowly get you moving. infintesimally small amount of force, but its free and in space there is no resistance so you dont need much to get going/break surface tensino. there is none. read: it would take FOREVER
NASA/JPL has an engine they have used for a few years that is very startrek. its called an ion engine, and it basically is a plate of copper that emits ions out the back (emits a cool blue light too). it only provides thrust pressure equivilant to the weight of a sheet of paper in ones hand, but it uses almost no fuel, and can run for years on a liter of xeon gas. acceleration is painfully slow, but the price/performance ratio is nice. it is used in some of those comet chasers as of late. takes months to get up to 100km/h, but in another month you are at 1000km/h, another month 10000km/h, 100000km/s
right, nice long, no one will read it anyway...
-------------------- take care, outerwave
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ChuangTzu
starvingphysicist



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Re: Speed of light travel [Re: outerwave]
#5356323 - 03/02/06 04:20 AM (17 years, 10 months ago) |
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Quote:
outerwave said: physicists are not know for creative naming
Balderdash! You studied particle physics, you don't find the nomenclature of subatomic particles creative? Beauty, charm, color, strangeness... Then there's the eight-fold way. Gluons...
People just don't give physicists enough credit these days. Ever since Feynmann kicked the bucket we're just a bunch of smelly geeks in wheelchairs.
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outerwave
shuffler ofmortal coils...


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Re: Speed of light travel [Re: ChuangTzu]
#5356346 - 03/02/06 04:47 AM (17 years, 10 months ago) |
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hell no it's not just people wheel chairs... sure, Mr. F was engaging, but so is Leon Lederman, a handful of authors that can deliver the concepts to you low and slow, but most importantly, with wit and charm.
physics is one of those last frontiers that really has no boundries. i mean, we can learn everything there is to know about a resus monkey, even simulate its brain on a computer eventually, but there always seems to be a smaller, single 1 dimensional point in space kinda particle just over the next gigajoule.
its the closest thing to divine mystery if ever experienced... oh christ it gets me excited... i was young and wide eyed round the time neutrinos and higgs bosons were all the rage. i think it was the end of highschool and the director of Argon Labs came to the physics class for a lecture... ended up chewing his ear off and it was just so invigorating... years later i just have come to terms that i don't have the computation skills to deliver the goods... concepts, yes, skills in application, i dunno...
(since its 5:40am and i cant sleep) one of the other great mysteries in my opinion is bio chem/life science stuff. everyone argues about how life got here... no primordia ooz, none of that. i just was reading some papers on how metabolizm came before orginized cellular structure. apparently, all you needed is 11 atoms, maybe a lightning strike, and walla, you have various 11 atoms componds competing for resources, give it a lot of time, and you have more complicated competing structures, that eventually will over power the competition.
like multi-spore mycelium!
eventually these compounds organize, then RNa, then life... peachy.
it's all about the big questions, nothing else holds my attention...
-------------------- take care, outerwave
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outerwave
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Re: Speed of light travel [Re: ChuangTzu]
#5356351 - 03/02/06 04:50 AM (17 years, 10 months ago) |
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the names are brilliant. who says genius savants don't have a sense of humor and such.
i used to have a shirt that i printed the Standard Model of Particles on... good times that.
-------------------- take care, outerwave
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ChuangTzu
starvingphysicist



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Re: Speed of light travel [Re: outerwave]
#5356368 - 03/02/06 05:09 AM (17 years, 10 months ago) |
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Quote:
outerwave said: hell no it's not just people wheel chairs... sure, Mr. F was engaging, but so is Leon Lederman, a handful of authors that can deliver the concepts to you low and slow, but most importantly, with wit and charm.
Totally man, I was being sarcastic. Now get some sleep
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Diploid
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Re: Speed of light travel [Re: outerwave]
#5359459 - 03/02/06 08:49 PM (17 years, 10 months ago) |
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if a new planet were to just pop into existence in the solar system, 1 light year away from earth (for example) you would think, since _nothing_ is supposed to go faster than light, it would take one year for the gravitational pull to reach to earth and effect us. when actually, that 'field' or 'beam' of gravitaional pull INSTANTLY starts pulling on its surroundings, be they 10 feet away or 10 light years away
This is not so.
Classical (Newtonian) physics incorrectly presumes instantaneous propagation of gravity, but General Relativity says otherwise. In fact, one of the things that lead to General Relativity was a discrepancy in the Newtonian calculation for the precession of the orbit of Mercury. The discrepancy was a mystery until Einstein's penetrating insight into the nature of gravity and the mathematical discovery that it DOES NOT propagate instantly.
If a disturbance in a gravity field traveled faster than C, it would invalidate General Relativity, violate causality, and summarily throw all of modern physics out the window.
That gravitation propagates at C has even been confirmed experimentally (though it was no surprise) a few years ago by astro-physicists with a little help from Jupiter's great mass.
-------------------- Republican Values: 1) You can't get married to your spouse who is the same sex as you. 2) You can't have an abortion no matter how much you don't want a child. 3) You can't have a certain plant in your possession or you'll get locked up with a rapist and a murderer. 4) We need a smaller, less-intrusive government.
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DieCommie

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Re: Speed of light travel [Re: Diploid]
#5359520 - 03/02/06 09:02 PM (17 years, 10 months ago) |
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Quote:
Diploid said: if a new planet were to just pop into existence in the solar system, 1 light year away from earth (for example) you would think, since _nothing_ is supposed to go faster than light, it would take one year for the gravitational pull to reach to earth and effect us. when actually, that 'field' or 'beam' of gravitaional pull INSTANTLY starts pulling on its surroundings, be they 10 feet away or 10 light years away
This is not so.
Classical (Newtonian) physics incorrectly presumes instantaneous propagation of gravity, but General Relativity says otherwise. In fact, one of the things that lead to General Relativity was a discrepancy in the Newtonian calculation for the precession of the orbit of Mercury. The discrepancy was a mystery until Einstein's penetrating insight into the nature of gravity and the mathematical discovery that it DOES NOT propagate instantly.
If a disturbance in a gravity field traveled faster than C, it would invalidate General Relativity, violate causality, and summarily throw all of modern physics out the window.
That gravitation propagates at C has even been confirmed experimentally (though it was no surprise) a few years ago by astro-physicists with a little help from Jupiter's great mass.
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outerwave
shuffler ofmortal coils...


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Re: Speed of light travel [Re: Diploid]
#5360049 - 03/02/06 11:32 PM (17 years, 10 months ago) |
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Gravitation, unlike electromagnetic forces, is a pure geometric effect of curved space-time, not a force of nature that propagates. there are more theories of relativity than einsteins. most notably lorentzian relativity which has proved favorable over the old methods.
theories such as causality are there to be improved upon. even then they don't need to be invalidated, just an occasional change in perspective. if you don't view gravitational radiation as a propagating force, there is no conflict. (now if i can change perspective in such a way that will pay my rent, i'm all set) the world ended up not being flat, the sun didn't orbit the earth, there is more to atoms that earth wind fire and water. the whole driving force behind unified theory is that conflicting things are true. it is this same 'contradiction' of facts that gave rise to general relativity in the first place; frames of reference, constant c, etc...
do you have the year and/or figures behind this experiment? my last course of study in the field was around 2000 (living down the block from fermilab helps too). but it is just that curved space predictions are the foundation of modern physics, string/M theory, etc... that these are still going strong leads me to believe that this experiment didn't have the profound impact i'd expect.
-------------------- take care, outerwave
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outerwave
shuffler ofmortal coils...


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Re: Speed of light travel [Re: DieCommie]
#5360103 - 03/02/06 11:49 PM (17 years, 10 months ago) |
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welp, did some quick research and here is what i've found so far. in 2001 S. Kopeikin proposed the experiment you mentioned, the latest update came on 1/8/2003. since then pretty much all of his work has been invalidated or disproven. the major grief of academia was that there was so much hype around his papers that several fundamental flaws were overlooked by the public. since then six experiments have confirmed that gravitational effects 'travel' possible a _billion_ times faster than light.
in this experiment Kopeikin stated "? a moving gravitating body deflects light not instantaneously but with retardation caused by the finite speed of gravity propagating from the body to the light ray. ? We calculated this correction for Jupiter by making use of the post-Minkowskian approximation based on the retarded Lienard-Wiechert solutions of the Einstein equations. ? Speed of gravity cg must enter the left side of the Einstein equations ? This will lead to the wave operator depending explicitly on the speed of gravity cg." None of these statements is correct even in General Relativity, provided only that "the speed of gravity" retains its classical meaning for the past two centuries of force propagation speed. The Einstein equations require the potential field of all bodies to act from the body's instantaneous direction, not its retarded direction, because they set propagation delay for the gradient to zero. But Kopeikin adopts the Sun acting from its instantaneous position and Jupiter acting from its retarded position, which is inconsistent. In fact, although the Sun moves 1000 times more slowly than Jupiter, it is 1000 times more massive, making any hypothetical retardation effects comparably important. The Lienard-Wiechert equations consider retardation in mutual distance, but not in direction ? the latter being a much larger effect of propagation delay. And the parameter on the left side of the Einstein equations is c2, and therefore has nothing to do with the speed of gravity, as we noted above. This does not prevent Kopeikin from calling it "cg" and solving for this parameter as if it were the speed of gravity, which is what he has done.
Kopeikin here ignores both the existence of a long-standing controversy about the speed of gravity (defined as the propagation speed of gravitational force) and the aforementioned arguments raised against his original interpretation by others. Kopeikin used the notion that this experiment might determine "the speed of gravity" to aggrandize the experiment, and perhaps also to justify funding for doing it. Yet the cg parameter measured is more closely related to the speed of light per se than anything else.
anyway, thats in a current journalof modern physics. and the names discrediting his findings read like a who's who in quantum physics and cosmology. basically he cheated to find funding is what people are saying, which is actaully rather common in research fields...
-------------------- take care, outerwave
Edited by outerwave (03/03/06 12:04 AM)
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ChuangTzu
starvingphysicist



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Re: Speed of light travel [Re: Diploid]
#5360667 - 03/03/06 04:59 AM (17 years, 10 months ago) |
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Quote:
Diploid said: Classical (Newtonian) physics incorrectly presumes instantaneous propagation of gravity, but General Relativity says otherwise. In fact, one of the things that lead to General Relativity was a discrepancy in the Newtonian calculation for the precession of the orbit of Mercury. The discrepancy was a mystery until Einstein's penetrating insight into the nature of gravity and the mathematical discovery that it DOES NOT propagate instantly.
As far as I know, no experiment has ever been conducted to directly measure the speed of gravity. The validity of Kopeikin's results has been under debate for a few years and I'm not sure that was ever satisfactorily resolved. Experiments have been designed and are being conducted to measure the speed of gravitational waves, which are generally assumed and believed to travel at speed c, but if you calculate, for example, the orbits of a binary pulsar system using general relativity and the assumption that the gravitational force "propagates" at speed c, you get weird effects like a net increase in the angular momentum of the system over time. Cosmology isn't my field but last I heard, this was the subject of an active debate.
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Diploid
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Re: Speed of light travel [Re: ChuangTzu]
#5361690 - 03/03/06 02:04 PM (17 years, 10 months ago) |
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the speed of gravitational waves, which are generally assumed and believed to travel at speed c
Waves is what I mean by "a disturbance in a gravity field".
-------------------- Republican Values: 1) You can't get married to your spouse who is the same sex as you. 2) You can't have an abortion no matter how much you don't want a child. 3) You can't have a certain plant in your possession or you'll get locked up with a rapist and a murderer. 4) We need a smaller, less-intrusive government.
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ChuangTzu
starvingphysicist



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Re: Speed of light travel [Re: Diploid]
#5362192 - 03/03/06 04:33 PM (17 years, 10 months ago) |
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Unlike with electromagnetism for example, where all field interactions are mediated by quantized units, general relativity has no such units for gravity. Thus, a conceptual difference exists between the speed of propagation of the force itself due to mass and the speed of propagation of gravitational waves. Think of electrostatic fields vs. EM radiation. One is produced by charge, the other, by accelerating charge. The gravitational analogues are mass and accelerating mass.
It turns out that I was wrong about the angular momentum bullshit I was spouting before. GR incorporates some clever machinery to make it appear like gravity is propagating instantaneously when actually it is a velocity-dependent, non-central force (think electrodynamics)[ 1].
Still, nobody has yet directly measured the speed of either gravity itself or gravitational waves and GR is definitely not the final answer. So maybe it will turn out that what is accomplished by mathematical trickery in GR is physical reality in another model if/when such a measurement is done.
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