Can Superconductors Block Gravitational Fields? 481
jswitte writes "Raymond Chiao, of the University of California at Berkel, believes that superconductors can convert electromagnetic radiation into gravitational radiation. His full paper can be found here. His theory is based on the idea that superconductors might be able to block the so-called 'gravitomagnetic' field just as they block the electomagnetic field in the famous Meissner effect allowing superconductors to levitate in magnetic fields. He claims that when he 'adds the gravitomagnetic field to the standard quantum equations for superconductivity, he confirms not only the gravitational Meissner-like effect but also a coupling between the two breeds of magnetic field. An ordinary magnetic field sets electrons in motion near the surface of a superconductor. Those electrons carry mass, and so their motion generates a gravitomagnetic field.'"
Note that it can't generate antigravity fields (Score:2)
Military applications (Score:2)
Not that this wouldn't prevent the usual research into military applications. I wonder how much force is generated, how much enhancement of force is created per megawatt?
Insert visions of UFOs with terrawat gravity generators, using this as a weapon to nuetralize gravity at an area of the surface below them. Enemy troops go drifting off into vaccuum or fall from a substantial height back to the ground.
NB the weather effects as well, of all of that atmosphere going up an anti gravity shaft, creating a storm.
Re:Note that it can't generate antigravity fields (Score:2)
Though regardless, once you know of this explanation, it seems totally obvious. Though really, I think you could just explain it by saying that more sensitive receivers mean signals don't have to be broadcast as far, and thus are going to be harder to detect against interstellar noise. A civilization doesn't need physics to invent a new form of communication to prevent themselves from being detected; they just need to apply a few decades of engineering to the problem of efficient radio. By this argument, we may already be undetectable to any distant civilization that might be searching.
Re:Note that it can't generate antigravity fields (Score:2)
I'll believe it when I see it. (Score:4, Insightful)
If it doesn't happen then that's also fine, it means that a hypothesis was shown to be not an accurate model of how the universe works.
The method described is science in action, the way it is supposed to work.
Of course if this does work then they are going to have some surprises when they enable those underground superconductive power cables in, IIRC, downtown Chicago. (Detroit? Somebody help me out here, please?)
-C
Re:I'll believe it when I see it. (Score:2)
Extrordinary claims need extrordinary proof. Build the device and demonstrate that it works. Publish the specs. Have other people who are not associated at all with you build these devices. If they confirm the results then the claim can be made relatively authoritatively. If it doesn't happen then that's also fine, it means that a hypothesis was shown to be not an accurate model of how the universe works. The method described is science in action, the way it is supposed to work.
Of course the way science really works is that the 99% of people who propose kooky ideas like this, and who don't work for a university, get labelled as cranks while this guy gets recognition and publicity based solely on some back of the envelope speculation.
-a
Re:I'll believe it when I see it. (Score:2, Insightful)
God I get sick of hearing that. Given that we know that current scientific models inevitably get overturned for new ones, and given that a claim can only be considered extraordinary (a judgment on the claim) from within a given scientific model (ie it seems to defy it, or seems very improbable within it), why should extraordinary claims be held to a higher standard of proof? Why can't *all* claims be held to an equally high standard?
Re:I'll believe it when I see it. (Score:4, Insightful)
Re:I'll believe it when I see it. (Score:2, Funny)
Fuck the Hypothesis!
The Scientific Method is for losers with too much time on thier hands!
Re:I'll believe it when I see it. (Score:5, Informative)
...the method described is science in action, the way it is supposed to work.
No, actually this isn't how things work these days. Science has become so specialised that there are very, very, few people that can do both theoretically and experiemental work at the cutting edge.
Most of us have a fairly good knowledge of a very small corner of one field, a slightly less good knowledge of the entire field, and an educated layman's knowledge of the rest of our discipline. Outside of our own discipline our knowledge is fairly scanty, most physicist's knowledge of chemisty for instance is probably no better than your average layman.
It's just not possible to keep up with everything even in your own field anymore.
The characteristic of bogus (or "junk") science is theories that give predictions that are untestable, or theories that predict things that have already been proved experimentally to be untrue.
While I haven't read the paper, not alot of point as I'm not a quatumn physicist, and my knowledge of quatumn field theory is fairly basic, this guy seems to have made predictions which are provable. This is good science. Whether he is right or wrong is imaterial (to the scientific process), his theory is interesting enough that some experimentalist will pick this up and run with and then we'll find out whether the theory is correct (or not).
Just because he hasn't provided extrordinary proof, doesn't mean that he's doing bad science.
Al.Re:I'll believe it when I see it. (Score:3, Insightful)
Re:I'll believe it when I see it. (Score:3, Informative)
Re:I'll believe it when I see it. (Score:4, Funny)
Of course not.
It's quantum mechanics.
Duh.
Mmm... Time machine (Score:2, Insightful)
As for the theory, it doesn't seem plausible, but physics is full of implausible concepts that work out in real life. Since gravity is a manifestation of a warpage of space-time, does this also mean that he is claiming superconductors are equivalent to gravity wells?
No doubt that the symmetry between Maxwell's equations and Einstein's equations is stark, but does this also mean that they are equivalent in meaning and applicability? Though the article puts a dig into superstring theory at the end, isn't it exactly this type of theory that is needed to unify such disparate theories as gravity and electromagnetism? If there is a symmetry there, wouldn't it make sense that the two equations would derive from a common principle?
My elementary physics is no match for the mathematics in the paper.
Re:Mmm... Time machine (Score:5, Informative)
If superstring theory is correct, then they've been known to be equivalent since the 1920s. The Kaluza-Klein equations show that in a 5-dimensional space-time (4xspace + 1xtime) or higher, Einstein's equations and Maxwell's equations both come out. See Kaku's Hyperspace [amazon.com] for more info.
Re:Mmm... Time machine (Score:2)
Cause or effect?
Does mass produce gravity that produces a distortion in space-time..
or is it a distortion in space-time that produces the illusion of the gravity associated with a mass?
Can we exceed the speed of light? Of course we can -- just combine the theories of Einstein with the observations of Gallileo...
Einstein tells us that the mass of an object increases infinitely as we approach the speed of light. This has been taken by most to mean that accelerating a mass beyond the speed of light would therefore require infinite energy.
But hang on -- Gallileo correctly determined that the acceleration of an object when acted on by a gravitational field is independent of its mass (air resistance not withstanding).
So -- if we use an external gravitational field to accelerate an object, the fact that it will gain infinite mass is irrelevant -- because it will maintain the same acceleration regardless.
Hence -- black holes and their immense gravitational pull are our secret to faster-than-light travel.
Now if I could just hitch one up to my mountain bike I'd be away
Special Relativity doesn't work that way... (Score:2)
You don't add velocities linearly in special relativity, they add in such a way that they can never exceed c in any reference frame. In order to move faster than light, you need either a discontinuity or an effect in a domain not covered by SR (GR, quantum,
Special Relativity is a really cool system, but it doesn't act intuitively - it all falls out of the simple assumption that everybody always sees light as moving at c relative to their own reference frame (no matter how fast they are moving).
There's a nice intro to a bunch of the concepts involved here [earthlink.net] (sorry, requires flash).
An implausibility with superconductors (Score:2)
- Make an ice chest out of single-crystal high-temperature superconductor. (Can't be done in practice yet, but nothing theoretically impossible about it.) The chest is a single crystal, the lid is another single crystal machined to very close tolerance. No gaps when you put it on.
- Cool the ice chest down to liquid-nitrogen temp and run a current through it. It is now superconducting, and it is now non-conductive of heat. Put in this ice chest a solid piece of frozen oxygen or whatever you like that's cold cold cold.
- Lid on, current now running through lid too.
You are now keeping a piece of oxygen frozen solid at little more than the energy expenditure to keep some nitrogen liquid. Sounds like it doesn't compute, but a cryo guy told me it would work. (Shoulda patented it...)Re:Mmm... Time machine (Score:3, Insightful)
Surely. Isn't it properly spelled "Berzerkely?"
As for the theory, it doesn't seem plausible, but physics is full of implausible concepts that work out in real life.
True enough. Yet the more implausible they seem, the more I suspect them of being over-convoluted theories that just _happen_ to match the results. Some things that seem implausible from a macro (visible, Newtonian) point of view are believable, but a lot of the quantum-level theories are just guesswork, as far as I'm concerned. Physicists must publish _something_ to keep their jobs, and that's what I think drives too much of the recent scientific theorizing. Publish something! That's their bread and butter. And they can write up for grants to pursue Big Physics research... and jobs. For example, fusion research is all simply a massive boondoggle.
Since gravity is a manifestation of a warpage of space-time, does this also mean that he is claiming superconductors are equivalent to gravity wells?
Another interpretation is that the space-time warp of gravity is a big illusion... that gravity isn't about mass but about energy (and mass and energy are related, thus the illusion). Thus the photons which have no mass _do_ have its analog... energy, and thats what gravity acts upon to bend the path. There _must_ be a consistent explanation for both macro and quantum level interactions, and until we find it, we'll not be intellectually fit to travel into the cosmos. We've got time (depending on when the next major comet intersects Earth's orbit at the wrong moment), but we do really need to figure everything out before our time runs out for us here.
No doubt that the symmetry between Maxwell's equations and Einstein's equations is stark, but does this also mean that they are equivalent in meaning and applicability?
My intuition tells me that such mathematical symmetries are trying to tell us something, but we just haven't figured it all out well enough - yet. We need free thinkers in the physical sciences, but... the entire structure of academia is built to enforce conformity. Some few people survive it and think "outside the box" as it were (Feynmann comes to mind), but the majority are just buried in conformity. The best thing the politicians could do to advance science would be to grant all science graduate students Associate level pay with no obligations to serve their tenured colleagues, but maintaining their freedom to consult and even collaborate with them whenever they find it helpful. This would accelerate big science in a way that would make the last decades seem a backwater.
Though the article puts a dig into superstring theory at the end, isn't it exactly this type of theory that is needed to unify such disparate theories as gravity and electromagnetism? If there is a symmetry there, wouldn't it make sense that the two equations would derive from a common principle?
Yes. Superstring theories (there are several that are trying to agree, convolutedly) are all so very complex that they're ultimately not very credible. Sorry! (To a generation of theoretical physicists.) The Universe _must_ have some simple rules (Einstein would agree with this, I am sure), but you haven't figured them out, so far. Complex systems are the products of insufficient mentality in both science and large-scale software systems. The bottom line for me is that I'm not convinced that they're not just playing with irrelevant and really fantastic math that will never work right. When they go outside five dimensions (3 space, 1 time, 1 energy), I lose interest. Or maybe six (vector/spin). But you maybe will get my drift... ten, twelve, fourteen dimensions? Give it up already!
My elementary physics is no match for the mathematics in the paper.
Mine too.
Re:Mmm... Time machine (Score:2)
Why? This is a most extraordinary claim. Are you prepared to produce your extraordinary evidence?
Oh, and a quote from Einstein that I rather like, ""Everything should be made as simple as possible, but not simpler."
It's funny: when I read this I got a mental picture of a race of blind people discussing physics and introducing this bizarre concept of "energy waves" that travel around, and people getting bored by it because it's obviously just an overly complex theory being shoe-horned onto reality.
Do you have any evidence, or even any reason to believe, that there are in fact not seventeen dimensions and we just don't have the necessary organs to readily percieve them all as being distinct?
Bear in mind that without sight or our kinesthetic sense, there would be no especially good or convincing way to tell that space had 3 dimensions to it.
Btw, when the view that you are currently advancing was put forth on some other topic a few weeks ago, a name for was mentioned that seems highly appropriate: "proof by instant gratification". How do you maintain it with a straight face?
Re:Mmm... Time machine (Score:2)
Do you have any evidence or reason to believe that there's not an _infinite_ number of dimensions? Why not? If you accept (with _no_ supporting evidence) 10 or 12 or 14 dimensions, why not go for 10,000 or so dimensions, or 10**80 or so dimensions. It makes no difference! It's all just imaginary, just conveniently approximate math to justify what the so-called "scientists" do with large amounts of public moneys, which they waste.
I'm no Luddite (a step-daughter did theoretical quantum physics until she transferred into astrophysics last year), but I'm skeptical.
Re:Mmm... Time machine (Score:2, Interesting)
Well, you seem to forget the reason why those extra dimensions were put in string theory! The K-K equations show that adding an extra (curled up) dimension makes EM a consequence of GR. So, in simple terms, you do see the extra dimension, but you "measure" it as EM charge. The other dimensions are added up to provide for the other charges (i.e. weak and strong charges). Is that so strange? Not to me, not stranger than allowing for phantomatic "charges" (what is EM charge made of?).
So basically, we don't have an infinite number of dimensions because we don't have an infinite number of different possible charges.
Re:Mmm... Time machine (Score:2, Troll)
See Occams Razor (the original statement, much abused since), which was roughly "Don't multiply entities beyond necessity."
To me, that translates to deprecate imaginary dimensions in quantum mechanics, beyond necessity. Necessary means observable.
To me, superstring theory is just too fantasical to stand. Sorry, Hawking, et al. I don't buy it, the Universe doesn't work like that.
I think we ought to demote most of the physicists in academia to teaching positions - no "research" for about 5 years or so. Then let students loose on the issues, but with none of that former apprenticeship culture that has held back several generations of scientists.
I call bullshit (Score:5, Insightful)
Yes, academic credentialism is driven by publishing. So? How does that translate into your assumption that all the 'recent theorizing' is bunk? Publishing is hard work. You don't just make up crap and watch is magically traverse the gauntlet of peer review.
Oh, right, because there's no such thing as fusion. That's why we know it's a boondoggle. Oh wait. It seems fusion is actually a common physical process! Maybe we should look into it. If, you know, that's all right with you. Work up the math, develop a consistent theory with provable axioms, then we'll talk. This isn't consultancy, s390, this is science. Golf, blowjobs, and 'intuition' won't cut it. Oh, and physics on LSD went out 20 years ago.Have you actually *read* the General Theory of Relativity? Go get Wheeler's "Gravitation". It deals with your confused theory, and much more besides, all coherently.
There are things to be said in favor of conformity. Science was created in a time of mystics and frauds. Actually having to prove what you claim was a big jump, and conformity is a natural side-effect of that. On the other hand, there is too much conformity in the university environment these days, but for that the blame can be laid at the doors of the administration. Nationwide, administration staff has doubled relative to student&faculty populations. All the bone-headed management theories that the private sector spent the last decade or two working through have trickled into the Uni, and all the 'free thinkers' fear for their jobs. Tenure, the great bulwark of high-performance original thinkers, is on the way out. Work through the math, get back to us. Perhaps if your 'scientific intuition' was better grounded in, say, math and science, then you wouldn't troll with this garbage. Oh, we broke the Standard Model 3 years ago. Better update your notes.IANAG I am not Alec Guiness (Score:2)
Well, from a certain point of view though....
At some level some publishing is, "I've noticed this quirk. It that light at the end of the tunnel illumination, or sunlight shining in my sphincter?" Sometimes in Physical Review Letters I would come across what would appear to be fairly formal flames. And other times the multitude of arguments leading to contradictory conclusions would individually be so compelling I wouldn't know what to think.
At some level all theorizing starts out as bunk, and the successful ideas percolate to the top. But I'm hardly an expert.
Sorry, no anti-grav (Score:3, Informative)
Re:Sorry, no anti-grav (Score:4, Informative)
If you mean "gravitational waves", then no, they are *not* different from the curvature of space. It's exactly the same stuff, though gravitational waves passing close to the Earth are probably very weak.So yes, they look like ripples on our pretty flat curvature, but they're just smaller-scale, generally weak curvature perturbations on a much more uniform background curvature.
As an aside, the term "gravity wave" is usually taken to mean "wave formed by a process where gravity is significant", like some types of water wave. Not actually what's been talked about here.
Sidebar says no anti-grav (Score:5, Informative)
Re:Sorry, no anti-grav (Score:2, Funny)
Uh dude, can you get a velco towel like the rest of us? It's doing that thing again.
This has been around. (Score:3, Informative)
Re:This has been around. (Score:4, Informative)
Excerpt of the article in the paper version of SciAm:
Sigh...cynicism kills! (Score:3, Insightful)
Re:Sigh...cynicism kills! (Score:2)
Not necessarily.. you should clarify that to *scientists willing to do the research* need to have an open mind. The rest of us can go along with "believe it when I can buy it for $49.95 at Wal*Mart" stance and the world will be just fine.
My not believing (or understanding for that matter) that this stuff works, doesn't have any impact on the future at all
Re:Sigh...cynicism kills! (Score:2)
You'll be seeing this at the Sharper Image [sharperimage.com].
"Dude! You have a computer game in your bag. My computer has a built-in mouse and this game with goblins. You gotta burn me a copy of that on CD! You suck!"
-Orange-haired employee at the Sharper Image(2 months ago).
If it sounds too good to be true... (Score:4, Insightful)
This was in wired a while back (Score:2)
Why don't superconductors weigh less? (Score:2)
Re:Why don't superconductors weigh less? (Score:2)
Similarly, a plane in flight still weighs the same, but the air moving across its wings applies an equal upward force, keeping it aloft.
Re:Why don't superconductors weigh less? (Score:2)
Re:Why don't superconductors weigh less? (Score:3, Informative)
Thus, the superconductor is not affecting the gravitational field. It is in a sense becoming a magnet itself, producing an exact-opposite magnetic field. This new field simply repels the magnet, producing levitation. By far the coolest effect was spinning/flipping the magnet over the superconductor and having it remain levitated, as the superconductor's magnetic field was always a mirror of the magnet's.
Now, in this I am not talking about the article or paper (I just started reading it). I'm simply talking about the magnetic field that is induced in a superconductor by magnets. My only experience and knowledge of the subject was the experiment in high school.
Re:Why don't superconductors weigh less? (Score:5, Informative)
The paper talks solely in terms of affecting "gravito-magnetic" forces, which are those exhibited by moving masses (and generally only significant among masses moving at an appreciable fraction of the speed of light). Simply put there just isn't enough gravito-magnetic force in every day life to notice any change. If there were an appreciable gravito-magnetic force in ordinary everyday gravity then yes you could test it, though I'm not clear how to expect it to react.
To put things another way, Newton described gravity purely in gravito-electric terms and most of us will never notice the more complex gravitiational interactions that Einstein discovered and this physicist cares about.
Podkletnov (Score:2)
In any case, I'm not sure I believe any of this, but I think it's good that there are people thinking outside the mainstream.
Re:Podkletnov (Score:2)
Re:Podkletnov (Score:3, Insightful)
Personally, I think both are crackpots. But if crackpots publish scientific papers, they still should follow the rules of academic conduct, because the rules of academic conduct ultimately are what helps us sort out the real crackpots from the forward thinkers.
superconducters (Score:2, Informative)
Re:superconducters (Score:2, Funny)
[Nitrogen] is cheap and easy to acquire as far as gasses go.
I have some nitrogen for sale, if you'd like. Fair warning, though: it's a little contaminated. I think it's only about 75%-80% pure.
Not the first time... (Score:2)
IF this pans out ... :) (Score:2)
Where do we donate to erect a statute of him in Montana [imdb.com]?
BTW, I've noticed a disturbing trend of really smart people != me ...
Wait for the experimental test (Score:5, Interesting)
Nobel prize material if it works. Footnote in Physical Review Letters if it doesn't.
Re:Wait for the experimental test (Score:2)
How? Are they actually *detecting* gravity waves?
Re:Wait for the experimental test (Score:5, Interesting)
So, if you imagine the following experiment:
Inside a Faraday cage, place a superconductor and a microwave source.
Inside another Faraday cage, place a superconductor and a microwave detector.
From inside the first Faraday cage, fire the microwave source at the superconductor. The theory predicts that a gravitation wave will be emitted.
Aim the (suspected) emitted gravitation wave at the second superconductor (inside the second Faraday cage).
Detect any microwave radiation after the gravitation wave has been converted by the second superconductor.
The Faraday cages block electromagnetic radiation so they ensure that no microwaves can leak from the emitter to the detector, and therefore gravitation waves must be the culprit.
podkletnov (Score:2, Informative)
not yet antigravity (Score:2, Interesting)
If what he claims is true then first of all he has invented a great new way to emit and detect gravitational waves. It would be awesome for astronomy, useful for submarine communication (and maybe detection), and probably many other things. However, it's not immediately obvious that we're talking "antigravity" here, so don't get too excited.
Also keep in mind that 99+ times out of 100 these sorts of claims are completely bogus and a waste of time. Just sit tight and wait for rebuttals or confirmation to appear on the LLNL server.
Free Advice for Fringe Physicists (Score:2, Insightful)
If Dr. Chiao is worried about his reputation, or getting published, or arguing with critics, I have some free advice: discover first, publicise second.
The article claims "By the time the theory is vetted, though, Chiao will probably have conducted his experiment and settled the question." Wonderful! Wait a few months to actually do the experiment, then publicise it. His reputation will be safe, everyone will want to publish it, and critics can try the experiment themselves. He will probably be able to complete it faster because he won't have all these clueless reporters asking him questions.
But you have to discover it first.
Re:Free Advice for Fringe Physicists (Score:5, Insightful)
Re:Free Advice for Fringe Physicists (Score:2)
Also note the references... (Score:2)
Re:Free Advice for Fringe Physicists (Score:2)
It is not always the scientist who is responsible for publication. It also happens that university staff hear about some discovery that may or may not be valid, and chat about it during lunch with someone who knows a reporter, who then publishes some wild story. Scientist's career is ruined, but hey, at least we sold a couple more newspapers...
I had a friend once . . . (Score:3, Interesting)
I had a friend who was working on this for a while. He kept building larger and larger metal units, cooling them down more and more, trying to get a rotating disk to speed up in a very, very, strong (par. magnetic field). If it sped up, then this was a reduction in the moment of inertia, and a decreased effective mass.
After two years of working on it, he gave up. He did get a measurable increase, but it was too little to be more than measurement error.
Re:I had a friend once . . . (Score:3, Informative)
He did get a measurable increase, but it was too little to be more than measurement error.
Do you realize that your statement does not make any sense? If he got not more than a measurement error could acount for, then he did not get a measurable increase.
Re:I had a friend once . . . (Score:3, Funny)
The reverse..? (Score:2)
Can this work in reverse to create a gravity field? Artificial gravity on the space station, for example. Or doubled/tripled/quad gravity in a lab on earth to test equipment intended for planetary exploration. I'm sure somebody could use that, if it's possible.
That said, I think somebody needs a girlfriend... Or the "The Simpsons" Season 1 Box Set and a DVD player.
This might answer some questions... (Score:2)
Note: I'm not especially expecting this to be true, just wondering what it would mean if it WERE true. I'm also just a computer science student, and am acting more as a philosopher than a scientist proper.
If it were true that gravity can be "generated" from matter by setting it up in a special super-conductive state, then sending energy at it, then we could learn several things.
First, we could learn if gravity is faster than the speed of light. This also means that faster-than-light communication would be possible, and eventually a form of faster-than-light information-conversion-based travel.
In addition, a new form of travel may be possible by just sending a small gravity generator where you expect to go, and have the smaller object pull you towards your destination at a cheaper net fuel cost. There's a LOT of assumptions here though, and the very idea itself seems to go against many principles of energy conservation.
It would also mean that humanity would have an interesting opportunity to attract matter, and eventually counter the effects of universal expansion.
Through learning about the speed of gravity, if we find that it is "instant", it may be possible to learn the time scale of the universe.
We may also learn of the nature of the range and shape of gravity over distance. Things such as if it travels as waves that may miss particles, and if there are "weak" spots in it's eminations relative to the polls of an atom, and how often these waves may be emitted if they exist as such.
Of course, nothing says that even if this were true, that it would be in any way efficient to use energy to generate gravity. Perhaps there is no way we could even generate gravity fast enough through energy conversion to match the effects of a marshmellow. Or much worse, perhaps it would be ironically simple to make a device that would slam a distant asteroid, planet, or star into our world within a few decades of the first exeriment!
So, what else might this mean, either if it is true or false?
:^)
Ryan Fenton
Re:This might answer some questions... (Score:2)
Re:This might answer some questions... (Score:2)
What evidence do we have so far? (Score:2)
You'll forgive my honest ignorance - but I'm having a bit of a hard time finding more than indirect evidence pointing to the expectation that gravity should act like other recognized massless particle just because it travels like it has 0 mass - since that's just assuming it can't be different in any way in order to stick with one form of relativity.
The closest thing to direct evidence I've found for gravity travelling at light speed is in observation of the changing orbits of binary pulsars, and the like - but this is not really a satisfying set of evidence for me. It assumes so many aspects of gravitational ratiation escaping and the like, that it really doesn't seem a clear picture so much as a loose interpretation based on existing assumptions.
Also, in another part of this thread, I posted this link:
http://www.ldolphin.org/vanFlandern/gravityspeed.
, which seems to be a frequently-posted link in discussions like these. I find that the path of discussion in that link has at least a few points valid enough for me to realistically doubt that gravity must act like a conventional form of radiation. I'd definetly be interested in any evidence, and I'm not at all attached to the notion that gravity acts in one way or another - so, if there's some argument or logic I'm missing, lay it on me!
:^)
Ryan Fenton
Re:What evidence do we have so far? (Score:2)
Re:This might answer some questions... (Score:2)
http://www.ldolphin.org/vanFlandern/gravityspeed.
Again, I'm not acting as a scientist proper in this thread - but the speed of gravity in this context is meant to mean the speed at which the force itself "moves", not the speed at which objects affected by it move. The question essentially is: At what rate does the pull from one mass end up having an effect on another mass' acceleration?
:^)
Ryan Fenton
I'm too stupid... (Score:2)
Not Anti-Gravity (Score:2, Interesting)
Related links to vodoo sciences available here (Score:2, Funny)
The problem with this theory.... (Score:2)
I haven't read the original article, but my guess is that the author is either working from some very simplified (linearized?) gravitational field equations, or else the author is somewhere making an assumption that these electrons in motion will have a negative contribution to the stress-energy tensor. And that's a big assumption. You may be able to write down pretty and symmetric equations which result in antigravity, but to date every examination of gravity has shown that it is asymmetric and the only thing we've ever found is positive contributions to the stress-energy tensor...
Has a gravitomagneticfield been proven to exist ? (Score:3, Insightful)
There is plenty of moving mass in the universe. Has anyone measured a gravitomagnetic effect?
i havent heard of it.
Re:Has a gravitomagneticfield been proven to exist (Score:2)
The problem is that there is either big mass moving slowly or small mass moving fast. You need a big mass to move fast to get a measurable effect. A supernova in our galaxy should generate a gravitomagnetic field big enough to measure with current sensors. On average, they happens once every few hundred years. We just need to wait...
IIRC, the gravitomagnetic field has been measured indirectly by observing the slowdown of a rapidly rotating binary star. The rate of deceleration not accounted for by other effects matched the predicted amount of energy it was supposed to lose by radiating gravitation waves with very good accuracy.
Finally.... A second use (Score:2)
Remember Eugene Podkletnov? (Score:5, Informative)
Dr. Podkletnov was discounted as a hoax by many sources (cited that rising gases from the coolant, air flow from spinning or magnetism influenced his results), his university ejected him and now he has retreated to a hermetic existence.
Here is a story on Wired [wired.com] for your reading pleasure.
Much more to look if you search Google [google.com].
It's not anti-grav. (Score:2)
Re: (Score:2)
I've reproduced the experiment (Score:5, Funny)
I took a tin pie tray and stuck it in the freezer for a couple of hours.
Then I rummaged through the attic and found that old turntable that used to scratch all my Barry Manilow LPs back in the '70s.
After running an extension lead from the socket on the kitchen bench over to the freezer, I stuck the plate on the turntable, set it to 78RPMs and let her rip.
The inital results were somewhat disappointing. Several spiders and a rodent that was either a very large mouse or a small rat ran out the back of the turntable and disappeared into a bag of frozen mince -- but the pie tray didn't lift up an inch.
Not to be discouraged, I figured that perhaps the reduced gravitational field only appeared above the pie tray -- so I grabbed the cat (which just happened to be passing by at the time) and pressed its warm little bottom onto the frozen pie tray.
I guess it was a little cold for him because he didn't half get excited -- or maybe I should have taken that spindle out of the center of the turntable first -- oh well.
Anyway, after a bit of hissing, growling and some bleeding (my blood not his), the cat eventually settled down enough for me to release him.
He sat their with a glazed look in his eyes and once again I flicked the switch to 78 RPMs.
Horray -- Success!
The cat lept several feet into the air, schrieking, hissing, wailing and spinning wildly at what I figured was probably 78RPMs.
But alas, the effect was short lived.
No sooner had this levitated feline lifted into the air than he crashed back down onto the rotating pie tray.
Ah, what the hell -- I slammed down the freezer lid and sat down in front of the TV with a beer.
I'll go back later and see whether he's settled down. Maybe tomorrow.
Anyway -- it looks as if there is some effect there but measuring it requires the use of protective garments and probably a more cooperative cat.
Now there's some guy called Schrodinger at the door asking whether the cat in my freezer is dead but telling me not to open the lid.
What the hell's going on there I wonder?
At least 30 names dropped in body of paper... (Score:2)
Starring, in order of Apperance
Raymond Chiao
Meissner
Lense
Thirring
Ginzburg
Landau
Hertz
DeWitt
Lagrange
Hamilton
Papini
Josephson
Anandan
Cooper
Minkowski
Aharonov
Bohm
Sagnac
London
Newton
Cart
Avagadro
Gauss
Ohm
Maxwell
Ampere
Einsten
Faraday
Coulomb
Shroedinger
Fresnel
Fitelson
Re:At least 30 names dropped in body of paper... (Score:4, Funny)
Scientific American Settles it... (Score:3, Interesting)
Perhaps that's a bit too harsh, but Scientific American has come down in the world quite a bit since the late eighties or early nineties. As I recall, they got a new editor many years ago and he was hell bent on dumbing the magazine down, fluffing it up with low-attention-theshold filler, and generally reducing it to a level of depth, insight, and relevance typical of USA Today or Omni Magazine. He suceeded, and many of the science professionals I knew cancelled their subscriptions shortly thereafter.
This subject strikes me as the researcher noting to himself "oh, hey...if I make some interesting assumptions, I get this cool effect popping out. And I might as well test it since it's so easy to test." Or an April Fools joke*. Which falls short of us dismissing the idea out of hand, but does suggest it doesn't deserve much media coverage -- at least until any positive results are verified. In other words, it was just sensationalist enough to get Scientific American's attention (they dig this kind of stuff), but not so far to the side of quackery that it has (yet) been featured in the Fortean Times [217.206.205.129].
* By the way, the paper missed April Fools day by four days; the date is stamped April 5, 2002. There's also a second date stamp of April 11, 2002. (A slightly earlier date stamp would have cleared things up pretty quickly!)
Wot, no Cooper pairs? (Score:2, Informative)
Imagine a discreet electron moving through a positive lattice. The positive lattice will be attracted towards the negative electron. If the electron was still, the lattice would move towards it locally, and screen its charge. Because the electron is moving, and the lattice has intertia, the positive induced charge will lag behind the electron. This will slow down the electron, and also might attract any following electron if it is traveling at roughly the same speed. This is often described as electron-phononon coupling, and is rather more complicated than that simple explanation would suggest, but there is a weak force that does tend to cause electrons to match their velocities provided they maintain a respectful distance.
If electron-phonon coupling was all there was, then metals would only superconduct at a few milliKelvin. However the electrons are moving so slowly, and their wavelengths are so long, that each electron wavefunction may overlap with many thousands of others. If some of the electrons go into some ordered state, then it becomes energetically more likely for the neighbours to fit in too, and all of a sudden you get an energy gap between the ordered (superelectron) state and the disordered eletron states. This energy gap is much larger than the individual pairing energies.
If you are going to get the same sort of coupling and condensation using gravitiational waves, then you are going to need to balance the gravitational force with some sort of other repulsive force with the right sort of range. You might find this sort of balance in a neutron star, but I don't see it happening in the lab. But maybe I'm missing something...
Finally! (Score:2)
Now if they could only explain how The Flash manages to run so quickly without eating the entire national surplus...
Far Side (Score:3, Insightful)
This paper reads the same way... "When A is time-independent, this equation has the same form as the time independent Schrodinger equation for a particle (i.e., a Cooper pair) with mass m2eff and a charge e2 with an energy eigenvalue except that there is an extra nonlinear term whose coefcient is given by the coefcient x, which arises at a microscopic level from the Coulomb interactions between Cooper pairs [16]. The values of these two phenomenological parameters must be determined by experiment."
But then again, what do I know?
Re:Thats one camp (Score:2, Funny)
Re:Thats one camp (Score:3, Funny)
Apples!
Very small rocks
Cider
Mud
Churches!
Lead Lead!
A Duck!
Re:Thats one camp (Score:2, Funny)
Re:Thats one camp (Score:3, Funny)
rofl
Re:Thats one camp (Score:2, Funny)
Throw 'er into the pond!
Re:Temperature is a hurdle (Score:2, Interesting)
Re:Ginger 2....now this is IT ;) (Score:3, Funny)
Nahhhh... (Score:2, Insightful)
This innovation will bring about nothing but high speed, heavily armed hover craft racing.
Oh, I don't know. The porn industry always figures out how to utilize some new invention before anybody else. I think you'll see some kind of floating blow-up dolls at PornDEX before your precious pod racers come along...
Ah (Score:2)
Re:Electricity? (Score:2)
Re:Electricity? (Score:2, Informative)
Re:Electricity? (Score:2)
Re:Communication (Score:2, Informative)
Re:What? (Score:2, Informative)
Re:if im reading this right... (Score:2)
The thing that attracts us to the ground is a static field; this is only an effect of dynamic fields. Just like AC + DC. What you feel now is a more or less static field. A dynamic gravitational field at, well, any noticeable frequency would feel, I imagine, incredibly weird, like an fast rollercoaster.