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CERN Experiment Indicates Faster-Than-Light Neutrinos
intellitech writes "Puzzling results from Cern, home of the LHC, have confounded physicists — because it appears subatomic particles have exceeded the speed of light. Neutrinos sent through the ground from Cern toward the Gran Sasso laboratory 732km away seemed to show up a few billionths of a second early. The results will soon be online to draw closer scrutiny to a result that, if true, would upend a century of physics. The lab's research director called it 'an apparently unbelievable result.'" Also on the AP wire, as carried by PhysOrg, which similarly emphasizes that the data are preliminary.
Update: 09/22 20:43 GMT by T : Reader Curunir_wolf adds a link to the experiment itself, the Oscillation Project with Emulsion-tRacking Apparatus, or OPERA, which "was developed to study the phenomenon of neutrino transmutation (neutrinos changing from one type to another. The speed of the neutrinos, of course, was an entirely unexpected observation."
EOM
SJW: Someone who has run out of real oppression, and has to fake it.
I searched for 'faster than light' on the CERN website, got articles posted in 2012, 2014. They put this new discovery to work right away!
Pavlov wouldn't be so famous if he'd used a can opener instead of a bell.
This was a rational piece without too many sensationalist remarks! How do we show them we appreciate decent scientific writing as opposed to the crap we normally get?
actually they are saying that this is off by about 6 times the error factor
"CERN says a neutrino beam fired from a particle accelerator near Geneva to a lab 454 miles (730 kilometers) away in Italy traveled 60 nanoseconds faster than the speed of light. Scientists calculated the margin of error at just 10 nanoseconds, making the difference statistically significant. "
still i think somebody is getting a speeding ticket (attached to a Nobel Prize maybe).
Any person using FTFY or editing my postings agrees to a US$50.00 charge
And if it's actually an accurate result then it doesn't matter how small the value is. As soon as you break the speed of light by _any_ amount then the theoretical doors are wide open. According to Einstein breaking the speed of light by even just one nanosecond is _exactly_ as impossible as Star Trek variety warp speed.
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Tachyons, if real, cannot decelerate. They also have imaginary mass according to special relativity. Of course, perhaps relativity isn't as complete a theory as we once thought.
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There was a young lady named bright : who could travel much faster than light : She went out one day : in a relative way: and came back the previous night.
FTL != backwards time travel.
If light takes 1 day to travel a distance and an FTL neutrino takes 23 hours, 59 minutes and 59 seconds to travel the same distance and then reflect both back at the source, the neutrino arrives 1 day, 23 hours, 59 minutes and 58 seconds after it is sent. That is distinctly not the past.
Was it faster than the speed of light in the given medium or faster than the speed of light in vacuum?
The speed of light in a vacuum (c) is a constant. The speed of light in a non-vacuum is not.
Neutrinos have been observed coming from supernovae from light years away. There would have been a very noticeable time difference between the neutrinos and the light at that distance if this were true. (Any astrophysicists about to verify this?)
I'm skeptical. I think it was likely a wiring problem. It only takes a few centimeters of wire to make a 60ns delay, and these experiments are notorious for using many wires.
The numbers in the Reuter's article show the speed of light for neutrinos is 1 part in 40,000 times faster than the speed of light for normal matter.
I don't think this involves causality violations just yet. All our speed of light experiments to date involve measuring particles involving the electromagnetic force (protons, electrons, photons). Even if confirmed, it could be that there's some measurement error in the EM-derived speed of light, which the neutrino is immune to. In which case, it's not useful for time travel. It simply means our measurement of c was off by a smidge.
And given the small size of the result, if FTL neutrino communication is proved true, I expect the only real-world application would be financial companies trying to squeeze a few more nanoseconds off NYC-London communications.
The detector is 732km away for the emitter and light travels at 299 792 458 m/s. In one billionth of a second, light only travels 29.9 cm. If they are off in the precision of measuring a 732km distance by even as little as 30 cm (~1ft), then their timings will be off by 1 billionth of a second.
Consensus != universal fact. Consensus == our best understanding of universal fact. There's a difference. Real science is always open to upending.
And why would this result be impossible?
It's impossible according to current theories. It's not impossible that current theories are wrong, but very highly improbable to be wrong in this way, given the amount of corroboration we have for the speed of light being an absolute limit and for the time-dilation effects, which would cause faster-than-light particles to violate causality.
Nevertheless, the data is the data, and that's why they're publishing it. Somebody else will find a measurement error (most likely) or we'll get exciting new physics (much less likely, but would be pretty awesome).
Many have posted that the instruments were flawed or the scientists made a mistake, but not too long ago scientists were 100% certain that the world was flat too.
Actually, I'd say that was very long ago. Considering Eratosthenes not only knew that the Earth was round, but was able to calculate the circumference to remarkable accuracy way back in ~200 BC. Note that it wasn't him that decided the Earth was round, that was already common knowledge. He figured out the circumference.
Just because scientists currently believe that nothing can go faster than the speed of light doesn't make it so. Our views of the universe are always changing and saying that a result is "impossible", no matter how unlikely the result, is a bit short sided.
That's true, however as many others have pointed out, extraordinary claims require extraordinary evidence. A single experiment just isn't enough. If we have sufficient confirmation of faster than light effects, scientists will most certainly welcome the result. Unexpected data opens up new opportunities for lots of papers. Scientists live for that, literally. It's what puts food on the table :)
Eh, this happens every few years... what tends to be the case is someone gets a hold of one of the charts where velocities were recorded and due to measurement issues there is a probability curve rather then a simple line... normally you use the curve to determine what the actual velocity was, but you always get at least a couple yahoos that look at the curve, notice that one of the tails goes above C and get all excited that something is going faster then light.
Good thing they are are going to put the findings online to be checked then (they have been looking for errors and have been unable to find any so far).
The result - which threatens to upend a century of physics - will be put online for scrutiny by other scientists.
In the meantime, the group says it is being very cautious about its claims.
"We tried to find all possible explanations for this," said report author Antonio Ereditato of the Opera collaboration.
"We wanted to find a mistake - trivial mistakes, more complicated mistakes, or nasty effects - and we didn't," he told BBC News.
"When you don't find anything, then you say 'Well, now I'm forced to go out and ask the community to scrutinise this.'"
Source: http://www.bbc.co.uk/news/science-environment-15017484
Yep it's a myth propagated by anti-science nuts. First popularized by religionists who were angry over evolutionary theory to try to discredit the science.
To me a nanosecond seems pretty big. I've spent a chunk of my time over the last couple of years designing consumer circuits sensitive to changes of 10ps in signal arrival time due to changes in the surrounding bulk dielectric.
You haven't lived until you've read a datasheet with the performance spec:
Deterministic jitter: 300 fs.
Probably a PECL part, but still.
And no, they're not using an instantaneous tau to approximate a decay distribution. Anyone who has ever cooked popcorn knows better than that.
And no, they're not using an instantaneous tau to approximate a decay distribution. Anyone who has ever cooked popcorn knows better than that.
Completely wrong. I've cooked popcorn and I have no idea what "instantaneous tau to approximate a decay distribution" means.
"That's a fallacy. Just because he's been crazy in the past doesn't necessarily mean he's being crazing now. Argue about the idea not the person."
It's a logical fallacy, which means it's technically a fallacy in a formal logic system. The fact that he's been crazy in the past doesn't PROVE he's crazy now. However, being crazy in the past is significantly correlated with being crazy now, so the likelihood he is crazy now is increased by his being crazy in the past.
As for the "idea," his basic idea is summed up by the sentence "Of course they're wrong, but I can't tell you exactly why." The quoted paragraph, for example, is ridiculous - you can take a noisy but unbiased measurement and improve the margin of error by averaging over many measurements (which is of course what they did). As for the rest of it, he brings up a lot of things that suggest faster than light particles are theoretically problematic - of course they are. I didn't see any part where he actually addresses the experiment itself, although I did start skimming a bit after reading a page long random story about a pigeon shitting in his pants.
This is ridiculously stupid and simple to ask, but I'll fire away anyway...
Never stopped me before, why now?
Did they or do they have some way of sending a 'normal' light signal, like say a powerful radio wave, across the same distance and measuring the travel time? If they see it's 60ns longer than the neutrinos then I think we're getting somewhere, neh?
I do not respond to cowards. Especially anonymous ones.
This is actually the most likely and rational solution, believe it or not. I posted this as well (it's taking time to read down this huge thread). A "vacuum" might actually be full of stuff, and as we have shown, light can be slowed and even stopped/frozen, given the right matter and space to interact with. If C is as fast as light can go in normal space, well, subatomic particles that don't necessarily interact with space the same way (and tend to go through it entirely) very well could travel faster. Exactly like how light travels through water at a specific speed. "Space" might be also be slowing it down.
Given the mass difference between a photon and a neutrino (yes, a photon does have a stupidly tiny mass, though it's calculated - and way beyond any of our detectors currently), the actual speed of light in a real environment where nothing is creating drag on it might very well be thousands of times faster.
No rules get broken. Einstein simply assumed (wrongly) than a vacuum was apparently empty when it's not as far as light is concerned. Note - even his theories are intact, as the "in a vacuum" clause still holds true.
If we detected a neutrino pulse would we have a good enough estimate of direction to look for the light? Or even the notion that we *should* look for a pulse of light several years later in the same region of sky? If we did record both by happenstance, would anyone have correlated the two events? That is weird enough that I'm thinking they wouldn't.
refactor the law, its bloated, confusing and unmaintainable.
I am intimately familiar with the interaction of light with matter as a result of having been an avid Amateur Telescope Maker and Amateur Astronomer since the tender age of twelve.
This led to my acceptance to study Astronomy at Caltech in the Fall of 1982, where I was privileged to attend a non-credit class called "Physics X" that was taught by The Immortal Richard Feynman. You could ask him any question you wanted - it didn't have to be about Physics even - but the ensuing discussion had to be purely conceptual. Questions that would require Feynmen to work out equations on the chalkboard were not permitted.
One afternoon I pointed out to him that the phenomenon that light slows down as it passes through a medium just had to be wrong. When one examines any medium at a subatomic scale, it is mostly empty vacuum with some rare particles that have all been either proven or are suspected to be geometric points. (While Protons and Neutrons have a non-zero diameter, they are each composed of three quarks, which themselves are thought to be point particles.)
"Surely," I pointed out to Feynman, "When light passes through all this vacuous space inside a piece of glass, it always travels at precisely C! How could Snell's Law" - which yields the angle of refraction when light passes through the surface of a medium - "possibly be correct!"
I knew damn well that Snell's Law was correct, as Snell himself experimentally demonstrated the law hundreds of years ago. While he did not measure what the Speed of Light had to do with refraction, we have been able to measure light's speed for over a century.
Feynman replied that when light passes through matter, the charged particles in that matter oscillate in sympathy with the oscillations of the light's electomagnetic field. But because they are all in a bound state, and because accellerating charged particles causes them to emit light of their own, thereby carrying away energy and so dampening their sympathetic oscillation, the movements of the charged particles in matter is not quite in phase with the waves in the light passing through the medium.
Feynman concluded, "The light emitted by the charge particles in matter interferes with the light passing through the medium" - that is, wave peaks add to wave peaks, and so with troughs, while peaks and troughs together cancel each other - "so that the resulting combination of light waves only appears to move slower than C."
Thus the Photons are always moving at a constant velocity of C, but all the Photons in the medium interact so that passing a Photon through the medium will result in the exit Photon being delayed from the timing you would expect from when the entrance Photon entered the front surface. They key to understanding all this is that the entrance and exit Photons are NOT THE SAME PHOTON!
Feynman discusses this in a really lucid way, with rigorous mathematics, in Volume II of The Feynman Lectures on Physics. Volume II covers Electricity and Magnetism, Volume I covers Classical Mechanics - Newton's Laws of Motion and such - while the third volume does Quantum Mechanics. The set of three is expensive but are easy to read, even if you don't know much Calculus, and would be a good investment for any Slashdotter.
I was mortally embarrased to realize years later that I had asked Feynman a really basic, purely conceptual question whose completely rigorous answer led to him sharing the 1965 Nobel Prize with Tomanaga of Japan! Their Quantum Electrodynamics describes the interaction of light with electric charge with complete precision.
Feynman's formulation uses a conceptual drawing called a Feynman Diagram as a calculational and explanatory device. I don't know how Tomanaga formulated his Quantum Electrodynamics, but my understanding as that at first no one could understand why the two theories seemed quite different but always yielded the same numerical results. Some time later Freeman Dyson - Esth
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