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Physicists Propose New Kind of Quantum Tunneling
KentuckyFC writes to tell us that scientists from the UK and Germany are proposing a third kind of quantum tunneling. They propose that a quantum particle is capable of changing into a pair of "virtual particles" capable of passing through a potential barrier before changing back. The supposition also provides some interesting methods of possibly testing string theory. So many interesting and useful possibilities, I guess that just means it will be debunked faster than other scientific theories.
So many interesting and useful possibilities, I guess that just means it will be debunked faster than other scientific theories.
Your glass the wrong size often there, mate?
A good percentage of us believe FTL travel is possible. You came to the wrong place with that attitude.
Qxe4
...but the evidence is clearly stacking up that quantum theory, and with it string theory & m-theory, are pretty much all wrong and utterly flawed.
[citation needed]
[b.belong('us') for b in bases if b.owner() == 'you']
Where's the revolution when you need one?
In the spirit of flammable open-source retorts: so, where is it? Post a patch or STFU.
[b.belong('us') for b in bases if b.owner() == 'you']
Where's the revolution when you need one?
Yeah, why haven't you been doing your math and physics to create this revolution that you see so clearly?
The standard model isn't wrong, any more than newtonian physics is wrong. It works great until you get to the edges, then of course you need relativity, but no one knew that until a few hundred years after Newton when we started getting experiments with strange results. Einstein was the one who explained those results.
Physics models are explanations of what we observe, which is why experiments are crucial. Unless we make more observations, we will have nothing to do but extrapolate current theories, which as you mentioned, break down at extremes, since we don't have as much experimental data at those points.
You want a revolution? Make one!
Qxe4
.
Quantum Mechanics feed at Feed Distiller, come there and make your own feeds
You make a mistake in lumping quantum theory in with String Theory.
There is at present no evidence whatsoever that quantum mechanics, quantum electrodynamics, and so on are wrong. These theories are the best tested theories in human history (certain predictions about energy levels such as those in the hydrogen atom have been verified to 12 or so digits of accuracy.) Quantum mechanics is at this point the best tested and thus most probably correct theory in physics by far. This does not mean that there isn't another underlying theory that will make somewhat different predictions, but the differences would have to be fantastically small.
String theory, on the other hand, has basically no evidence against it, but also virtually no supporting evidence. This is mostly because it hasn't really come up with much in the way of testable claims.
Great!... Now we need to not only guess if Schrodinger's cat is alive or dead but also if it is still inside the box as well.
I just tunnel over SSH. It works fine...
From the paper, it looks like this is enough stronger than a hypothesis, to justify the appellation "theory". There's enough information to build detectors that can discriminate the rate of tunneling (if any, of course) between this virtual particle mode, the conversion mode, and "classical" (uncertainty) tunneling.
Time for the experimentalists to take their shot at confirming/denying this one.
One question, though, about the conversion mode: where's a reference for a description of the impetus for the conversion? Is it a sort of uncertainty where the "current" mode of the particle is one of the allowed states of its energy, an oscillation like neutrinos, or does the string (if you go there) pick up energy from an extra-dimensional impact (changing its "tune") then release it in another impact or emission to return to the previous state?
I am new to everything quantum. Is that barrier FTFA less than three dimensions? Or am I mistaking that barrier with something else?
And if that's the case, then isn't this dark matter just energy not 'captured by' the Higgs Boson particle or whatever it is that the Higgs is?
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There is always MoND, which explains some of the same things as "Dark Matter" and "String Hypothesis", and then there are also some recent findings that suggest that the Universe is not expanding after all... which would throw the String Hypothesis right out the window.
Maybe they are all in a way true. Einstein had it wrong with E=MC^2, but some parts of the two theories are probably true, like the light that bends, etc.
How about we stop flaming each other? Saying "That's BS" as a scientist, isn't exactly the way a scientist should be thinking and researching. The entire idea is that scientists prove and disprove parts of science by thinking beyond "Pffff BS" and "It's just the way it is because".
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(1) It's supposed to be funny.
(2) I'm not the one making the extraordinary claim that quantum theory is utterly flawed.
(3) There's not enough days left in my life to slog through all the woo-woo sites that I'd get if I googled for claims that QM is wrong.
(4) I'm just fucking lazy, and like to poke fun at people making outrageous claims. This *is* Slashdot, after all.
[b.belong('us') for b in bases if b.owner() == 'you']
Mine was intended as humorous, too, so let's all relax.
Ok, Jane. I'm all relaxed, so very relaxed... what now?
I think we can keep recursing like this until someone returns 1
I thought that this was the exact idea behind Hawking radiation, but the barrier in that example was the event horizon of a black hole? I can't see that this is anything different except for the barrier? How is this a new idea?
They already don't quite understand the two types of quantum tunneling they already have, and they want to have a third? Everyone knows that you get your existing shit in order before you go expanding, especially in the current economic climate. Like two types isn't enough already anyway!
Who do they think they are, string theorists??
+1 Insightful for (4)
The fact that the current theory is so complex that theorists are still able to trawl through it and make all sorts of new predictions indicates to me that they're making it all up as they go along.
Oh really? And I thought god tells them how he build the world and they just write it down.
See, we don't have a handbook about how the universe works in some language we don't understand, and we just have to translate the pages. Making it all up as we go along is the only way there is. In the real world you can never proof that some rule applies. You can only gather evidence with observations. And it really is not that important whether the theory is true as long as it just describes our observations very good.
I never ceased to be tickled by people loudly and ignorantly arguing against the reality of quantum mechanics USING A MACHINE DRIVEN BY FUCKING SEMICONDUCTORS. Its like the flat Earth society getting its message out through satellite television.
Quantum mechanics, like any science, is not a religious doctrine. It doesn't have to be complete and all encompassing to be right; it just has to fit the observations for everything we have tried so far. When it stops fitting the observations, we will give it up (or more likely, refine it in some subtle way) and move on.
If we can put a man on the moon, why can't we shoot people for Apollo-related non-sequiturs?
But it is worth mentioning that any new physics at this point, be it MoND, String theory or anything else, is more like a refinement of existing theories than a complete overhaul. If we were very wrong about the laws of physics, then our technology which relies on being tightly fine tuned to them (space probes for Newtonian dynamics, GPS systems for relativity, anything with a semiconductor for quantum mechanics) simply wouldn't work. They do work, and the work with astonishing accuracy.
If we can put a man on the moon, why can't we shoot people for Apollo-related non-sequiturs?
I suggest you take up the notion that E=MC^2 is 'wrong' with a survivor of Hiroshima or Nagasaki. If matter/energy equivlance were wrong nothing nuclear would work. Including the Sun, which is essentially a giant, gravitationally bound, thermonuclear explosion.
The notion that light bends is not 'probably' true, it IS true because it was famously measured by Eddington during a solar eclipse. There seems to be some notion amongst the general public that Einstein pulled relativity out of his butt and physicists just accepted it because it was cool. This is not the case at all.
Special relativity was accepted because it explained phenomena that could not be explained by previous theories, and because it has been constantly verified by experiment ever since (time dilation has been measured on aeroplanes using very accurate atomic clocks, and mass dilation is a daily fact of life in any particle accelerator facility you care to name).
General relativity was accepted only because someone went out there, took some measurements, and saw they confirmed Einstein's predictions. Furthermore, we now have everyday technology that depends on GR being, admittedly within certain bounds, correct.
If we can put a man on the moon, why can't we shoot people for Apollo-related non-sequiturs?
Ok, Jane. I'm all relaxed, so very relaxed... what now?
Blowjob time.
I think you sum up quite nicely what a lot of people are failing to understand|: what ever new models / theories we come up with they have to account for everything we currently observe and the new things that current models / theories don't explain correctly.
I think a lot of people think that when we discover a theory of everything or at least the next quantum mechanics we will suddenly unlock the ability to teleport our selves, have faster than light travel and a multitude of other things that are strictly in the realm of science fiction. Taking faster than light travel as an example: everything we know tells us that it is fundamentally forbidden by the laws of the universe, that isn't about to change because we better explain the event horizon of a black hole. It's like saying that because we discover this amazing new theory the apple that hit Newton on the head would fall up rather than down! It might tell us how to generate anti-gravity but that is totally different to re-writing the rule book.
I used to have a better sig but it broke.
[Curses lack of mod points]
MoND does a good job of explaining rotation curves of spiral galaxies, but that's about it. It fails on the scales of clusters of galaxies, as even its proponents acknowledge. Nor does it make useful predictions for the growth of large-scale structure.
I have no idea what you mean when you say it explains the same things as the "String Hypothesis."
I object to using the term debunk when referring to disproving a scientific hypothesis that was put forth in good faith by those willing to have it tested. The word debunk means to expose bunkum - which originally meant empty speech and which came to mean claims made by people who knew they were spewing crap.
The proposed model may turn out to exist only in the brain of a couple of overcaffeinated physicists, but it is not bunkum and cannot be debunked.
If Slashdot were chemistry it would look like this:Cadaverine
It works great until you get to the edges, then of course you need relativity, but no one knew that until a few hundred years after Newton when we started getting experiments with strange results. Einstein was the one who explained those results.
I think you are giving Einstein a bit less credit than he deserves there. He spotted (some of) the flaws in the Newtonian model before there was any experimental evidence to contradict them. When he first published, his results were taken to be theoretically interesting but not particularly practically applicable - just interesting permutations of the mathematics. It wasn't until Eddington observed that stars appeared to move during an eclipse that there was an experimental result that contradicted Newton but not Einstein.
Quantum mechanics was the other way around. The double-slit experiment showed that the classical model was wrong, but there was no theory pre-existing to explain the result. A few years later, there were a lot of them, none of which was particularly satisfying (or easy to unify with relativity).
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There is no point arguing with anyone who quotes E=MC^2 as part of relativity. The correct formula, which anyone who studied physics at school, let alone university, would know has a momentum component as well. Special relativity is probably the most recent bit of physics that can be considered easy (i.e. school children can work out all of the underlying mathematics without too much help) and so trying to argue with anyone who failed to understand it is unlikely to be worthwhile.
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I think a lot of the blame can be given to the media, who use phrases like 'prove true' in physics articles. Physics is never proven true, it is only proven false or proven useful (in some cases both - Newtonian mechanics is the obvious example - we know it's wrong, but in most cases it's within a tiny fraction of a percentage point of being right, which is close enough).
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Technically yes, the 'correct' formula is more complex; but you use plain old E=MC^2 when you are working with nuclear reactions (because momentum is negligible in a solid lump of uranium) - and that is the context most people use it in.
If we can put a man on the moon, why can't we shoot people for Apollo-related non-sequiturs?
The proposed mechanism sounds vaguely like the the mechanism for Hawking radiation, in which a pair of virtual particles becomes separated at the Schwartzwald horizon of a black hole, with one particle being trapped forever inside the horizon, and the other particle becoming 'real' and escaping.
Theoretical physicists do come up with their best hypotheses on 4/20.
Prisencolinensinainciusol. Ol Rait!
It wasn't until Eddington observed that stars appeared to move during an eclipse that there was an experimental result that contradicted Newton but not Einstein.
Sorry, not an astronomer, but I was under the impression that the inability of Newtonian mechanics to properly account for the precession of Mercury was well known before Einstein's time...
Don't tell me to get a life. I had one once. It sucked.
That's something I've been wondering about.
- When people claim that string theory has no supporting evidence.. I'm wondering whether some classic tests which perhaps quantum scientists used to prove quantum theory lend themselves to test string theory as well?
Or is that the wrong way to think about string theory?
Your history is a bit off. During Einstein's time there was a lot of thought experiments along similar lines to that of Einstein. There were also many places were Newtonian physics could not explain the observations including, but not limited to, Mercury's orbit around the sun and the Michelson and Morley experiment.
The eclipse was experimental evidence that matched Einstein's prediction of what would happen according to his theory.
As for the double-slit experiment, I don't remember(memory is a bit fuzzy so could be wrong) it showing problems in classical physics until much later. The first experiments that really showed the quantum effects of light were the photoelectric effect (See Einstein, 1905) and Compton Scattering(Compton, 1923). I admit the really funny behavior associated with QM came later and the double-slit experiment played a role.
This is a problem I see quite often when people try to "counter" a popular scientific theory. They give an example of where the results get blurry and assume some new theory, right around the corner, will topple centuries of research and we will begin anew. Such things are an extreme rarity. For example, if we discovered an entirely new theory of gravitation, hypothetically, that better explains how large bodies move in space, it won't likely change the fact that here on Earth, gravity is fairly constant everywhere. And it turns out that mass ISN'T as constant as we once believed... but, quite frankly, when you're an engineer designing a bridge, it's constant enough.
New data rarely warrants throwing out the old data. It usually just adds new conditions. I.E., Mass is constant when at rest. As you pointed out, Newtonian physics works great under pretty much any circumstance you'll run into on Earth.
Yes; in principle the same sorts of tests that have been done for quantum mechanics could be done to test string theory. The example I gave above is a good one; string theory would predict slightly different energy levels for the hydrogen atom.
However, there is a slight practical problem. While we can measure these things to phenomenal accuracy (10 or 12 digits) the predictions of string theory would only become different from the predictions of quantum theory at somewhere in the range of 25 to 35 digits, depending on the theory. These differences are so far beyond our current ability to measure that there is very little hope for any sort of confirmation of string theory in the foreseeable future.
Because of this fact and the fact that there is no clear mathematical reason to favor one string theory in particular (there are infinite possible variations), string theory has in the end contributed essentially nothing to modern physics.
While I accept quantum mechanics and its power to describe the sub atomic universe, I still have no idea where this claim about QM being used in the development of the transistor comes from. I learned about transistors using a theory of electrons and "holes" and in fact this viewpoint comes from no lesser source than Shockley himself.
I've never seen a theoretical description of any transistor device that required any form of quantum mechanics for its explanation. Given the fact that transistors are to this day, macroscopic devices, I still fail to see how QM comes into their theoretical explanation. It's a subatomic theory.
May the Maths Be with you!
First of all, I'm not debating with you the usefulness of quantum mechanics and Quantum Electro Dynamics, instead I would like to stress the multiple interpretations of physics in a more meta-physical method. Lets put your argument into phlogiston theory, and see how it functions:
- modified quote ... satellite television.
I never ceased to be tickled by people loudly and ignorantly arguing against the reality of phlogiston theory USING A MACHINE DRIVEN BY FUCKING HEAT. Its like the
- end quote
Now for the second part of your argument: actually modifying a theory when it no longer fits the observations is something many bigot believers who are in the habbit of too theoreticaly interpretting their own religion, constantly do.
Most scientific changes have been brought up by fundamentally challenging the premises on which everything else is based, for example: is there an atom, or are there fields? do we view space as carthesian, as exponentional, in 3 dimensions or more? can we prove anything at all in certainty, by making observations? (a certain problem in Quantum Mechanics in relationship with induction) what logical language do we need to base our observations on, and does the logical language we use modify our view of the world?
Now, our current epoch in physics has been long standing, still based on the principles of relativity theory and quantum mechanics, fine-tuned, admittedly, but not fundamentally challenged. Come to realize there are differences in perception between those who view a theory as 'real' (there are indeed electrons, photons, etc.), and those who find a theory sufficient (giving no judgement on the existence of the former mentioned entities). Neither can be right, but both can twist the perceptual position of the interlocutor.
There is always MoND, which explains some of the same things as "Dark Matter" and "String Hypothesis", and then there are also some recent findings that suggest that the Universe is not expanding after all... which would throw the String Hypothesis right out the window.
MoND is more like a curve fit through all the existing data than an explanation of its cause. Every time some new piece of data shows up, the curve fit is redone and the mechanics of MoND change to match the new big picture. At any given time, it's self-consistent, but it's never made a prediction that was then proven correct by later evidence.
"I zero-index my hamsters" - Willtor (147206)
Only if they use gravity bongs.
Space game using normal deck of cards: http://BattleCards.org
This leads to a fundamental axiom, that truth is more of a philosophical concept than a scientific one. Sometimes that distinction can seem hazy, but I believe it's there.
Truly the best opening line in a /. post ever. I've thought it and am glad you said it.
There is no point arguing with anyone who quotes E=MC^2 as part of relativity. The correct formula, which anyone who studied physics at school, let alone university, would know has a momentum component as well.
You mean the total energy of an object also includes its kinetic energy? Thank you, Captain Obvious! You've certainly toppled damburger's house of cards.
Atheism is a religion to the same extent that not collecting stamps is a hobby.
I totally agree with you that quantum mechanics is very well tested and extremely accurate in every domain we can test.
However, it is known to be wrong. Quantum mechanics (and even quantum field theory) is incompatible with general relativity. As far as I know, no one knows how to reconcile the two. It's the same situation as blackbody radiation prior to quantum theory - we have one model that works on one scale, and another model that works on another scale, but they are known to be incompatible.
The difference is that we don't have the technology to build experiments in the contested domain - experiments in which we measure quantum effects in an acceleration/gravity field strong enough to have measurable GR effects at a quantum scale.
That said, there's another issue with quantum mechanics. To my knowledge, there is no clear definition of what a "good observation" is, or what happens in a non-good observation. For example, in the classic two slit experiment, you are either observing (entangled with) the electron as it passes through the slit, or you are not. But in fact, it seems to me you are almost always varying degrees of "sort of" entangled with the electron. By which I mean there are particles that interact with you that give you statistical information about which slit the electron goes through, but not clear information.
By the way, regarding the "new method" of tunneling in the post... that doesn't sound new at all, to me. The standard Feynmann diagram model of quantum mechanics involves identifying all the ways a particle could get from here to there (including splitting into other particles and rejoining) and summing over them to find the likelihood a particle will be at the target location. Not having read the article, I'm guessing they just analyzed those "split into two particle" paths and discovered that they contribute more in some scenarios than people had believed before.
Science was wrong about something in the 18th century != science is equally badly wrong about the nature of atoms now.
Machines that require phlogiston theory to be true simply would not work. Machines that require QM to be true do work, and they enable you to spout your ignorance of the subject to a wide audience.
If we can put a man on the moon, why can't we shoot people for Apollo-related non-sequiturs?
Let's not forget the black body radiation problem, which Max Planck observed went away if you made this weird assumption that light came in individual little packages whose energy varied with frequency. Of course, light was really waves, not packages, but it did make the calculations come out right. Einstein's contribution to the photoelectric effect was to show that it was also explained by those odd little quanta.
"When you have eliminated the unacceptable, whatever is left, however improbable, must be the truthiness" - Holmes
I guess that just means after extensive testing of this hypothesis, it may or may not lead to a theory..
Okay buddy, I fixed your post. It's a shame people still utilize the word 'theory' for almost every context. This is almost universally true with regard to science critics commenting on the very subject they hate.
Where's my sock? There it is...
Except that they're not. Well, MoND is... but "String Hypothesis" is a new, complex structure in it's own right. It may be designed to explain edge cases, but it is not a "refinement" of anything existing.
Neither has "String Theory" (to use the popular term, even though it's not a "theory" yet) predicted anything that could not be as easily explained by alternate hypotheses... so why are you singling out MoND? They are in exactly the same boat in that regard.
Are you trying to say that "String Theory" has not been used to try to explain "dark matter"? Of course it has.
Right. BTW, one of the earlier difficulties with estimating the age of the planet and time for evolution was that there was no known mechanism for the Sun to continue to shine for more than several thousand years. Something like somebody coming up with an explanation for things that includes a process that started a trillion years ago.
The notion among the general public you state is half right. Einstein did come pretty close to pulling relativity out of his butt. However, physicists didn't accept it because it was cool, they fought over weird concepts like relativistic time for a long time, until the physical evidence mounted up and physicists ran out of competing theories that made more sense to them.
Einstein strikes me as being very similar in some respects to modern cranks: working in an unscientific field (with the Swiss patent office), coming up with some sort of strange idea that invalidates some basic concepts. The difference is that Einstein did know a whole lot about modern physics (unlike virtually all such cranks), so he addressed existing problems in the theory, and turned out to be right.
Anyway, it's very reasonable to think that relativity isn't the final description of the behavior it applies to. However, any replacement theory will account for the massive number of observations already made, and so will agree with relativity in very many cases, and will come from somebody who is thoroughly familiar with relativity, and has as intuitive a grasp as possible. It will not come from somebody who finds relativity confusing or counterintuitive.
"When you have eliminated the unacceptable, whatever is left, however improbable, must be the truthiness" - Holmes
Ideas in physics are never proven true.
The insight above is basically the philosophy of science of Karl Popper. Theory implies experimental predictions. If experimental predictions are false, then theory is false.
Then Thomas Kuhn pointed out that it's even worse than that. Really, it goes: Theory+Auxiliary Assumptions => prediction. If prediction=false, then (theory=false OR auxiliary assuptions=false).
The OR in that statement can never be completely eliminated. For example, if you assume there is a small invisible planet somewhere inside the orbit of Mercury, you can exactly reproduce the results of General Relativity using only Newtonian Mechanics. With enough auxiliary assumptions, you can make any theory work.
Because of this, you can never completely falsify any theory either, which makes the process of switching theories very fuzzy, social, aesthetic, and generally much messier than scientists want it to be. Kuhn coined the term "paradigm shift" to describe this process.
"All proofs inevitably lead to propositions which have no proof! All things are known because we want to believe in them." -- Frank Herbert
My site: Free Nature Pictures
Ideas in physics are never proven true. They are shown not to contradict any existing evidence, that is all. I can't think of any more than a few decades old which have survived even this.
I can: Relativity (both Special and General) and Quantum Mechanics. These have been around for over 100 years (since 1905). SR and quantum theory are the two most precisely tested scientific theories ever.
Technically speaking, is it possible to know if something is *almost* universally true?
This won't be debunked, its true. Once you look at the feynman diagrams its obviously a possible effect.
If you read the paper and not the very bad summary in the article - along with a wrong diagram - then this is not what they are suggesting. They calculate the neutrino digram shown in the article and which you estimated and come up with a probability of O(10^-130) times a function of the neutrino mass, barrier thickness and photon energy. This would be an interesting way to measure neutrino mass if the probability were not so low.
What they are actually wanting to test is whether there are new, fractionally charged particles out there. So this is not something that is guaranteed to work. In fact I do not see how we would not have already seen such particles before now in virtual effects in K and B experiments if nothing else...but I have not looked at it in detail.
I find it interesting that I browse a site that casually has a story like this: "They propose that a quantum particle is capable of changing into a pair of 'virtual particles' capable of passing through a potential barrier before changing back" sandwiched between two stories about video games, as though they both belong in the same broad category (of "nerdy" or something).
Property is theft.
The standard model isn't wrong, any more than newtonian physics is wrong.
Sorry but we know that both Newtonian physics and the Standard Model are wrong - in the case of the SM we just don't know exactly how it goes wrong yet - other than neutrino masses which are easy to fix. Just because Newtonian physics works for everyday events does not make it correct - it is fundamentally wrong but it is a good and useful approximation to what is really happening.
In the same way the SM is also wrong. It has no explanation of gravity, a huge fine tuning problem and no explanation of Dark Matter and Baryon number violation. So we know that fundamentally it is wrong since it does not explain all the phenomena of the Universe we live in. However it is a very good approximation and correctly models all the phenomena we can produce in the lab. It is really what we call an "effective field theory" which means that it is a low energy approximation of a fundamental theory. Unfortunately we just don't know what that fundamental theory actually is.
With E=MC^2 I was reffering to his theory. I never studied his calculations...
What's wrong with his theories was that Einstein thought that the speed of light was the absolutee speed, which it isn't
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I believe it's actually the fourth. Quantum macroparticle tunneling was first documented in 1987.
While the speed of light may or may not be a cosmic speed limit, we DO know that we CAN not only slow down, but speed up light. So regardless if we can make things move faster than light, we can make light move faster than "light in a vacuum."
There was a /. article several months back about how some scientists in a lab were able to make light #1 move backwards, and #2 move backwards faster than it moves forward in a vacuum. Considering this, 186,000 miles/second is no longer the cap of speed.
hmmm, c - the speed of light - is absolute, in a vacuum.
If you're trying to point out that light goes different speeds in different media - that's well considered with Einstein's work.
If you're not, then what are you referring to?
If you're not, then what are you referring to?
To the fact that other things can go faster than light. What I was trying to say was that the speed of light is not the absolute speed in any given medium.
I forgot to mention an example: ÄOEerenkov radiation
http://en.wikipedia.org/wiki/Cherenkov_radiation
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