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borman
2009-Aug-10, 04:25 AM
The speed of gravity is thought to be the speed of light. Light has a maximum speed in a vacuum but can be considerably slower when traversing a medium. If gravity is not affected by a medium, then its effects can be registered in advance of the light arrival if the light had to travel even temporarily through a medium. Gravity waves may arrive much sooner than light from a supernova and the correlation might be missed. The gravity effects may correlate better with neutrino arrival.

However there may be special mediums that do modify the inertial effects associated with gravity. The presence of superfluid Helium either in liquid or supersolid form has been observed to lead to inertial anomalies. The Tate anomaly where the mass of a Cooper pair of electrons was measured to be significantly more massive than quantum mechanical predictions was the first anomaly to be noted in 1986. Later experiments exposing inertial anomalies were performed by Tajmar and also reported by Podkletnov. Under high pressure and very low temperatures supersolid Helium has been observed to give an inertial anomaly formally known as NCRI, or Non-Classical Rotational Inertia. The errors are several orders of magnitude greater than theory predicts.

So is it the speed of gravity that is being affected in these examples or is the coefficient of inertia suffering some holographic magnification because non-locality is imposing dimensional constraints?

m74z00219
2009-Aug-10, 04:57 AM
I don't know the answer, but I think your question is similar to what Chinese scientists are currently looking into.

http://www.newscientist.com/article/mg20327183.800-eclipse-sparks-hunt-for-gravity-oddity.html

m74

publius
2009-Aug-10, 05:17 AM
Under classical GR, it shouldn't be. There is no mechanism to increase the gravitational "dielectric constant" (which would be G, of course), nor the equivalent gravitomagnetic permeability( "ferro-gravitomagnetic" or para- or di- such effects).

But, of course, it could be, though. If they find evidence of such effects, then it's a big deal. Tajmar and deMatos (sp?) said the found evidence of increased gravitomagnetism by rotating superconductors, which would be a type of increased gravitomagnetic permeability, which they propose is due to the Cooper pairs behaving strangely gravity and inertia wise. They say this is the first hints of some strange quantum gravitational stuff.

Others dispute those results. If the Chinese find evidence of the so-called Allias Effect, then there we go.


-Richard

Neil Russell
2009-Aug-10, 06:03 AM
This one is way out, the electro magnetic spectrum is finite in the sense that they depend on atoms/elements to produce their photons etc. For example in a black hole matter is split/condensed down to a level where electro magnetic fields are no longer produced.
All we are left with is gravity( the infinite energy source) and well I believe we are looking at some infinite speed attractive force, it must be for nothing else can operate at infinite universe distances.

astromark
2009-Aug-10, 08:09 AM
Now, I do not know this subject well enough to answer it with absolute certainty but...
It seems reasonable to make the assumption that mass effects gravity. So that yes gravity can be interrupted, altered, effected, by the medium it transverses. after all gravity is the effect of mass. Mass is mater so its not unreasonable to make that leap that mater, or mass will and does effect the action of gravity force... mark.

rodin
2009-Aug-10, 11:55 AM
I love your question. The answer will be very interesting. My guess by analogy is that it will be slower. I look forward to experimental results in this area

Cougar
2009-Aug-10, 02:06 PM
However there may be special mediums that do modify the inertial effects associated with gravity.

Wouldn't the Earth's orbit change during a lunar eclipse then? Since it doesn't, then gravity would appear to be unaffected by having to travel "through" a medium.

NorthernBoy
2009-Aug-10, 02:22 PM
All we are left with is gravity( the infinite energy source) and well I believe we are looking at some infinite speed attractive force, it must be for nothing else can operate at infinite universe distances.

Why do you say that gravity is an infinite energy source? This is not a mainstream view.

Do you also believe that magnetism is an infinite energy source, or coulomb attraction?

a1call
2009-Aug-10, 04:16 PM
I would like to watch this thread, so:


Is the speed of gravity altered by a medium?

No, there is no basis for that assumption. There are more likely/logical causes for the pendulum anomalies as discussed on other threads on this board.

cjameshuff
2009-Aug-10, 05:10 PM
Energy is absorbed from gravitational waves by matter, and the resulting motion of the matter would re-radiate gravitational radiation, modified due to the mass and elasticity of the matter. Thus, effects like refraction and a reduced phase velocity of gravitational radiation should be possible. Note though that this is specifically gravitational radiation, not "gravity".

tashirosgt
2009-Aug-10, 05:39 PM
What if the speed of gravity could be altered by a medium? (What if I should start new thread to ask this question? I won't, but a moderator is welcome to revise that situation.)

I haven't been able to design an anti-gravity machine based on this assumption, but perhaps others can. A thought experiment that I can visualize is something shaped like a horseshoe with each arm of it having a different rate of gravitational transmission. At the top and outside of the horseshoe, I have a mass than I mechanically move to and fro, nearer and farther from the horseshoe in a sine wave. In between the open side of the shoe I have a mass suspended like a pendulum, which is to be driven by the gravitational changes. Will the driven object actually move from side to side between the arms?

astromark
2009-Aug-10, 07:44 PM
I see the old moon at eclipse being mentioned here again and feel the need to correct this error... Every 28 or so days the moon passes between the Earth and Sun. Yes that action is detectable but slight. Just 14 days later the similar action is repeated as the moon passes behind the Earth. Tidal effect and Earth rotation are all part of this seemingly confused idea. I also see that some would have me believe that gravity is not effected by the medium it transverses.. That's got to be wrong for a good number of reasons. Mass and gravity are close relatives. How could it not be so.

cosmocrazy
2009-Aug-10, 09:09 PM
thats assuming that gravity has a carrier particle, graviton? a photon has no mass yet is effected by gravity, we know that light can stopped in its tracks by a black hole. How would there be any exchange of gravitons between say 2 photons? Mass effects spacetime, changing its geometry. Is the rate of change observed to be no more or no less than c? this effect is observed by us as gravity. Until we understand the properties of gravity i can't see how we can deduce if the effects of gravity can be slowed down below c.

Cougar
2009-Aug-10, 09:17 PM
I see the old moon at eclipse being mentioned here again...

Whatever. My point was, the moon is a "medium" that the Sun's gravity has to "go through" on occasion in order to reach Earth. If the moon's medium altered the propagation rate of the Sun's gravitational effect, I expect Earth's orbit would be affected. Such an effect is not seen, to my knowledge.

With this in mind, I also wonder about the graviton hypothesis. I expect the Sun would emit a finite number of gravitons per Planck time. When the moon is between the Sun and Earth, how come the Sun's gravitons interacting with the moon don't seem to detract from the Sun's gravitons interacting with the Earth?

macaw
2009-Aug-10, 09:55 PM
Later experiments exposing inertial anomalies were performed by Tajmar and also reported by Podkletnov.

There is no independent verification (http://en.wikipedia.org/wiki/Eugene_Podkletnov#Attempted_verification) for the claims of Allais,Podklentov and Tajmar.

borman
2009-Aug-10, 11:59 PM
There is no independent verification (http://en.wikipedia.org/wiki/Eugene_Podkletnov#Attempted_verification) for the claims of Allais,Podklentov and Tajmar.

There have been a number of monitorings of the Allais effect, but they have not been consistent enough to warrant acceptance. NASA was interested enough in the Allais anomaly to launch an experiment, overseen by Noever, that spaned the US to Eastern Europe. While sensitive gravimeters in US failed to monitor an event, it was reported that some pendulums in Eastern Europe were seen to deviate and this was supposedly filmed. Unfortunately Noever and NASA had a serious disagreement and Noever left with the research data that has yet to be published. NASA's interest was motivated by their observations of anomalies in the gravitational assists during Earth flybys and an apparent acceleration upon two Pioneer craft. One idea put forth regarding the flybys involves a cosine function that can minimize the effect. This function has not yet been taken into consideration when trying to understand how the Allais effect is sometimes there during an eclipse and sometimes not.

The Tajmar experiments showed two humdred succesful examples of the inertial effects in the Austrian experiments. The experiments were then repeated with success in South America but with additional discoveries that the effect can tell whether the experiment is being done North or South of the equator as well as that the temperature range of the effect did not match the transition temperature of Niobium (a little below 8 degrees K)but rather the transition temperature range of superfluid Helium (max at 4 degrees K but hanging in there up to 30 degrees K where the last of the superfluid could not survive). Up to that time, it was thought that the effect was associated exclusively with superconducting, but then the effect should have stopped when Niobium no longer superconducts and the effect does not occur at 78 K where some high temperature superconductors continue to superconduct. The experiments gave no result at New Zealand where a lead disc was used instead of a superconducting ring. This could show a topological dependence when it comes to stirring the superfluid Helium bath.

All the same, a superfluid of electrons in Cooper pairs is still of some concern regarding the more recent research of Podkletnov who is investigating impulse research involving Cooper pairs. When experiments are performed at temperatures where the pairs do not exist, one just gets the expected null result. When one uses a normal metal substrate and applies high voltage across this and a superconducting superstrate, the Cooper pairs are displaced towards an anode in a coherent manner rather than they typical spark or arc. Upon crashing into the anode a seemingly very high speed coherent field continues, akin to a laser that registers an impulse upon objects in its path whose strength is related the applied voltage. 500,000 volts induces an effect similar to the Allais effect. 5 million volts apparently deliver quite a whack. The beam is reported to remain Gaussian and could be a threat to orbiting craft if they intersect its path. It could also serve as an interdiction device in the event a Near Earth Asteroid should threaten to get too close and needs a nudging away from a possible collision with Earth. Because of the unusual nature of the events, it is hoped that future publications might also be complemented with film evidence to spur efforts at independent confirmation.

The NCRI of supersolid Helium was performed by a different group of experimenters who had access to very low temperatures and high pressures to make the supersolid. It may be that the recent success of using the mathematics of string theory to problems in high temperature superconducting may offer a further understanding when applied to these other anomalies.

borman
2009-Aug-11, 12:31 AM
Under classical GR, it shouldn't be. There is no mechanism to increase the gravitational "dielectric constant" (which would be G, of course), nor the equivalent gravitomagnetic permeability( "ferro-gravitomagnetic" or para- or di- such effects).

But, of course, it could be, though. If they find evidence of such effects, then it's a big deal. Tajmar and deMatos (sp?) said the found evidence of increased gravitomagnetism by rotating superconductors, which would be a type of increased gravitomagnetic permeability, which they propose is due to the Cooper pairs behaving strangely gravity and inertia wise. They say this is the first hints of some strange quantum gravitational stuff.

Others dispute those results. If the Chinese find evidence of the so-called Allias Effect, then there we go.


-Richard




Clovis de Matos has an opinion on this effect and has recently (8-6-09) updated a paper:

Testing Loop Quantum Gravity and Electromagnetic Dark Energy in Superconductors
Abstract: http://arxiv.org/abs/0812.4993

Along with earlier work with Beck, he has been considering the possiblity of an Einstien-Planck level being responsible for the extra inertial effects.

The Tate anomaly had been considered in an earlier paper with Tajmar, but Tajmar later felt this idea has less than 10^-5 of being right.

IMHO, while I find the idea charming, I am a bit reluctanct to embrace it in the aftermath of the Tajmar South American experiments that showed the inertial anomaly to be more related to superfluid Helium than superconducting Niobium.

Another theorist to keep attention on regarding holography is Hogan who finds possbile large scale effects can result from a kind of magnification that normally would be too small to observe. This might be the noise in the GOES experiment. It is not a quantum gravity theory but uses the uncertainty principle to resolve a problem pointed out by Einstein late in his life used by Zurek in one of his more important papers.

As an example of a recent Craig Hogan paper:
Holographic Noise in Interferometers
Abstract: http://arxiv.org/abs/0905.4803

a1call
2009-Aug-11, 02:34 AM
There is no independent verification (http://en.wikipedia.org/wiki/Eugene_Podkletnov#Attempted_verification) for the claims of Allais,Podklentov and Tajmar.

Indeed, according to wikipedia (http://en.wikipedia.org/wiki/Martin_Tajmar#Gravitomagnetism_research):


In 2006, Martin Tajmar and several coworkers announced their claim to have measured a gravitomagnetic version of the Frame-dragging effect caused by a superconductor with an accelerating or decelerating spin [3]. As of April 2008, the effect has not yet been observed independently.
In February 2008, Martin Tajmar filed an international patent application for a "Process for the generation of a gravitational field and a gravitational field generator" [4].
In June 2008, Martin Tajmar retracts his first explanation of the phenomenon and he suggested that this is a new property of rotating low temperature helium [5].

IMHO there is some very-old bad-pseudoscience (antigravity beam above rotating superconducting disc which I remember reading about a few decades ago) is being mixed here with some legit phenomena (Allias effect). The verdict seems to be still out on the latter (though IMHO not deservingly).

publius
2009-Aug-11, 03:29 AM
Indeed, according to wikipedia (http://en.wikipedia.org/wiki/Martin_Tajmar#Gravitomagnetism_research):



IMHO there is some very-old bad-pseudoscience (antigravity beam above rotating superconducting disc which I remember reading about a few decades ago) is being mixed here with some legit phenomena (Allias effect). The verdict seems to be still out on the latter (though IMHO not deservingly).

What Tajmar and deMatos claimed was very different than the "anti-gravity beam" of what's his name, Podlenkov of whatever. Consider the so-called London moment of a rotating superconductor. Spin up a superconductor and a magnetic field develops. This does not happen in a regular conductor, and is a superconducting oddity. The superconducting quantum "entities" are well, "frictionless", and they don't move when the lattice is spun, causing a current.

Well, Tajmar wondered if there would be some similiar gravitomagnetic effect, and claimed he discovered one many orders of magnitude greater than what GR would predict for a rotating disc (the B_g field would be so small as to be undetectable, of course).

Just as a time-varying B field produces an E field (curl E = -dB/dt), so GR predicts a time-varying B_g field will produce a g field. The linearized version of the EFE, sometimes called "GEM" for gravitoelectromagnetism looks much like Maxwell, save for the odd factor of 2 (or 4 depending on how you do it) on the gravitomagnetic terms. The full EFE is of course a complex non-linear tensor field equation, but the GEM approximation allows you to see how it behaves in the same B-E dance as Maxwell.

So, by accelerating the disc (increasing the angular velocity), the B_g field would thus be time-varying, and thus produce a rotational g field above the disc. Basically, the lines of this g would be just like E around a transformer.

They claimed to have measured the gravitomagnetic induction effect.

This is nothing like the "anti-gravity" beam stuff, but something different. Now, many doubt this effect is real, of course, and I don't know what the current state of it is.

-Richard

publius
2009-Aug-11, 03:41 AM
Apparently no one has been able to repoduce the effects seen by Tajmar, so his enhanced superconducting B_g should be considered dubious.

From what I gather, most of the experts consider this, along with the Allais effect (and the Podlenkov anti-gravity, of course) as fringe. If you see anyone claiming, or especially hinting, at some cover-up/conspiracy of "strange gravity behavior", consider it fringe. Believe me, if someone serious found experimental evidence of gravity behaving in a way different from what the EFE predicts, well, it one be one heck of a big deal.


-Richard

a1call
2009-Aug-11, 03:51 AM
Yes by definition It is/was legit when under ESA flag (http://www.esa.int/SPECIALS/GSP/SEM0L6OVGJE_0.html).



It demonstrates that a superconductive gyroscope is capable of generating a powerful gravitomagnetic field, and is therefore the gravitational counterpart of the magnetic coil. Depending on further confirmation, this effect could form the basis for a new technological domain, which would have numerous applications in space and other high-tech sectors" says ESA study manager Clovis de Matos. Although just 100 millionths of the acceleration due to the Earthís gravitational field, the measured field is a surprising one hundred million trillion times larger than Einsteinís General Relativity predicts. Initially, the researchers were reluctant to believe their own results.

But the wikipedia article that was referenced states a retraction of his original claim, since.

astromark
2009-Aug-11, 04:56 AM
Warning.... Not everything you read in wicket-gate is the truth. ( Wikipedia ):)
Looking through this thread and others that have dared breach this subject... It would seem that good science and science fiction have become entangled... I have little doubt that super conductors are going to play important rolls in the electronics of the future. But fiddling with the known behaviour of gravity does not seem to work. I remain open to this suggested effect. As yet unproven.

astromark
2009-Aug-11, 05:46 AM
Having a second look at this I will now reject this as a not yet proven idea... That does not have a great deal to do with this subject of ' Does the medium of transferance effect gravities strength or velocity. When talking of the lunar aculting and being able to measure such an action or any effect of it. As yet no such effect has been documented.
This descusion regarding super conductors and gyroscopic rotations having effect on gravity is at best thin ... If proof of such is forthcoming please feel free to add here. I will listen. Right now its in the bin...with it.

jumpjack
2011-Jun-11, 09:58 PM
I heard about a researcher obtiaining "amazing results" with a superconductor disk spinning at 50'000 and 100'000 rpm; he also said he's going to build a team of a dozen scientist to study the phenomenon for next 5 years...
Does anybody know anything about this?

I also found ESA funded researches on the matter:
http://arxiv.org/ftp/gr-qc/papers/0603/0603033.pdf
http://lanl.arxiv.org/ftp/gr-qc/papers/0603/0603032.pdf

macaw
2011-Jun-11, 10:16 PM
I heard about a researcher obtiaining "amazing results" with a superconductor disk spinning at 50'000 and 100'000 rpm; he also said he's going to build a team of a dozen scientist to study the phenomenon for next 5 years...
Does anybody know anything about this?

I also found ESA funded researches on the matter:
http://arxiv.org/ftp/gr-qc/papers/0603/0603033.pdf
http://lanl.arxiv.org/ftp/gr-qc/papers/0603/0603032.pdf

Tajmar's claims have been shown to be bogus.

jumpjack
2011-Jun-12, 04:55 PM
where? when?

macaw
2011-Jun-12, 05:00 PM
where? when?

New Zealand, long ago: http://en.wikipedia.org/wiki/Anti-gravity#Tajmar_et_al._.282006_.26_2007_.26_2008.29

Tensor
2011-Jun-13, 04:20 AM
Here's (http://www.earthtech.org/experiments/tajmar/papers/SuperFrameDragging2007.pdf) the actual paper.

macaw
2011-Jun-13, 05:29 AM
Here's (http://www.earthtech.org/experiments/tajmar/papers/SuperFrameDragging2007.pdf) the actual paper.

Wiki goes on to say that Tajmar himself has withdrawn his claims.

jumpjack
2011-Jun-13, 07:25 AM
[deleted off topic post]