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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.
Looks like someone forgot to zero the clocks...
I hope those results are correct. It would be very amusing.
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.
The speed of light is the same regardless of the reference frame. That is what makes relativity fun. MY speed varies as a function of YOUR reference frame, but the speed of light is constant for everyone.
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
But the speed of light does vary in different materials as a function of the index of refraction.
Visit the
While the there is a good point buried in that question, the speed of light through dirt and rock, just like any other opaque materials, is, well, zero.
Put my fist through my alarm clock with its ding-dong death inside my ear. - The Blackjacks.
Not when traveling through something other than a vacuum. I think it's called refraction.
https://secure.wikimedia.org/wikipedia/en/wiki/Refraction
"Refraction is the change in direction of a wave due to a change in its speed. [...] Refraction of light is the most commonly observed phenomenon[...]."
Yep, refraction.
Do they mean the neutrinos are breaking c (the speed of light in a vacuum) or the local speed of light? Even the latter would be extremely interesting.
The ultimate test, of course, is to watch for many physicists start winning the lottery.
Article says that it's compared to light taking the same trip. That would imply it's the speed of light in whatever medium they're using.
It would be even more crazy if the neutrinos were going faster than c in some medium... that would essentially mean that neutrinos were behaving as if they didn't interact until 'we' decided to measure them. Not saying there aren't theories that could predict that, just saying that they're pretty much the craziest theories out there.
Ugh, I can't believe I'm actually going to do this but...
*nerd_voice*
I think the way a warp drive works is it folds space/time around the ship rather than actually propelling the ship faster than light. So the ship is never actually traveling faster than light, but it does wind up covering more distance than light does in the same amount of time.
*/nerd_voice*
If what I just said sounded like a troll, it was probably just a failed attempt at humor.
Article says that it's compared to light taking the same trip. That would imply it's the speed of light in whatever medium they're using.
Light tends not to travel through 'the ground' very well.
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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I'm not aware of any material that is opaque across the entire EM spectrum.
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.
FanFictionRecs.net
http://motls.blogspot.com/2011/09/italian-out-of-tune-superluminal.html
"...the neutrinos are claimed to have arrived 60 nanoseconds before the light. Because this is claimed to be a 6-sigma signal, their total error margin of the timing should be 10 nanoseconds (3 meters over c); recall that the distance is 732 km. I leave it to the reader to decide whether this accuracy is plausible given the messy birth and detection of the particles. One nanosecond is the duration of one cycle of your iPhone microprocessor, among other things. Ten nanoseconds is 40% of the lifetime of the charged pion or 80% of the lifetime of the charged kaon. I can kind of imagine that they're doing something really silly, like imagining that each pion or kaon lives at least for the lifetime and then it dies. But some of them decay immediately; this error could erase most of the 60-nanosecond discrepancy."
Dirt and rock is not blocking all wavelengths. Radio will pass through (with the speed of light).
NB: The message above might reflect my opinion right now, but not necessarily tomorrow or next year.
Somebody probably just left a slightly magnetized keychain next to something.
For all intensive purposes, "whom" is no longer a word. That begs the question, "who cares"?
They should just make c in E = mc^2 the speed of the nutrino.
Very interesting thought. Photons interact with matter all the time and have been shown to slow down when passing through certain media. Neutrinos rarely interact with anything, so of all the known particles, they are a candidate to travel at the maximum speed allowable.
Depends on the frequency. Low-frequency radio waves propagate reasonably well through the ground.
...creates reality. I like it.
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.
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.
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.
Visible spectrum, or all light?
Why not? The gates in your computer are faster then that.
I know they have tried to factor out obvious stuff, but wouldnt the rotation around the sun ( or galaxy) mean that its possible they're hitting a target that's moving "closer" to the source?
Hopefully it's c and not the local speed of light. The fact that neutrinos go faster than the local speed of light is not only well-known, it's one of the standard methods of detecting neutrinos. (Build a water tank in an abandoned mine and watch for Cherenkov radiation.)
And why would this result be impossible? 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. 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.
Except that neutrinos which pass right through dirt and rock like it's not there are still supposed to be bounded by the speed of light.
We're not talking about shining a flashlight here. :-P
Lost at C:>. Found at C.
I don't think Einstein ruled out Star Trek warp speed. Indeed I think it's relativity that warp speed depends on. Warping space to shrink the distance between points then traveled in less time at the same speed.
--
make install -not war
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.
60 ns / 2 ms is 3 x 10^-5. The speed of light has been verified to much better than that with photons (that would be a 7 orders of magnitude error on Mars ranging, for example, and about the same on LLR), so, if true, this is a neutrino issue.
My money would be on systematic error.
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.
Take a look at this useful primer about faster than light travel and what it would mean for modern physics. It sure would be interesting. No, amazing!
Duh, that's the point.
FTL is time travel.
Watch this Heartland Institute video
http://www.csa.com/discoveryguides/gravity/overview.php
Tachyons. Hand in your nerd card.
In common computer cpu we are manipulating matter and energy on an almost atomic level, and measuring what happens to mind boggling precision. All so you can lolcat on your mobile phone.
Since I didn't see their data, I can only guess what could be the problem. They're detecting both neutrinos and light some way. My bet is that their detector for light have some additional delay making the light detection wrong. They probably didn't spend millions on the light detection system since they were planning to detect neutrinos only. Probably cheap parts are causing this problem.
An oscilloscope with a bandwidth of 1 GHz or more. Such scopes are not terribly expensive, about $10k or so.
Consider that infrared rangefinders with a range of a few feet measure the latency between the transmission of an IR pulse and the return of its reflection.
:(){
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.
I feel like some of the claims we're hearing these days in the theoretical science community are publicity moves. If they're disproved, so what? They get free advertising; the loss of credibility seems to be negligible. On the other hand if they're are right, they are first to publish and get the attention. I, for one, will be watching for the news in the next couple of weeks/months that says the independent verification failed and they found an error in their data.
Yea but they did the test 15,000 times to confirm it before even mentioning it to the public.
Well, it was 60 billionths. It was "a few" in much the same sense that a teenager invites "a few" friends over when his parents are out of town.
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.
Indeed, according to Einstein, in the right reference frame it is Star Trek variety warp speed. Indeed, there's a frame of reference where the speed is infinite. And a frame of reference where the neutrinos were detected before they were generated.
In other words, there are only three possibilities:
* The measurement is wrong
* Relativity is wrong
* We can send messages to the past using neutrinos
At least one of those must be true.
The Tao of math: The numbers you can count are not the real numbers.
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.
How can your computer's processor execute multiple instructions in less than a billionth of a second?
If that were the case we would end up seeing massive relativist effects in the show, which do not happen. According to Einstein however quickly the Enterprise seems to be traveling or how much space has been warped from its perspective, from Starbase's perspective it's going to take years for Kirk to travel between one star and another.
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First Billion 1,000,000,000 or 1,000,000,000,000 ? Second How accurate did they measure the distance?
They sent one kind of particle and another kind arrived, according to TFA. They sent a Ford Pinto and a Testarossa arrived. Of course it arrived sooner than expected. Duh.
Consensus != universal fact. Consensus == our best understanding of universal fact. There's a difference. Real science is always open to upending.
The speed of light in a vacuum is the same regardless of the reference frame.
FTFY
"Convictions are more dangerous enemies of truth than lies."
Article says they eliminated possible sources for error but doesn't list them. Every scientific paper I've ever wrote had a section you had to list possible venues for errors in your experiment. I don't doubt they did, but I'd like to know what they were. I can't even get all my clocks in my apt to sync up to my computer or at work or to the tv or anything else. I imagine it's really hard to do this with two remote locations unless the clocks were perfectly synced in person and then transported to the different research stations. Otherwise, if they eliminated all possible known error sources could this have been a spacetime bend? We already know that matter/gravity bends spacetime. Perhaps there was a varying gravity density between the two stations? I know neutrinos rarely interact with matter but are they affected by gravity like photons are?
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
That would throw off calculations regarding the conversion of mass to energy.
I have always wondered how in the hell is the ratio of mass to energy exactly the speed of light squared? I don't quite see why they should be related, but the fact that they are should say something.
Don't know something? Look it up. Still don't know? Then ask.
Gravity follows inverse square law with distance if you were down far enough underground wouldn't the deformation of the metric be somewhat different due to significant masses below AND above you?
If you compared the underground effect with above ground laser results the true time/path length thru metric is slightly different.
It doesn't matter how you get there, if a message can arrive at it's destination faster than a message sent at the speed of light, you break causality. It's all well and good that you trick the math into indicating your speed through space never rises above c, that doesn't change the fact that your message is getting there outside of it's own light cone.
The physics of the past century do not empower us to send humans to other habitable planets. So...they need a good upending.
Thank you.
I am John Hurt.
I don't think Einstein ruled out Star Trek warp speed. Indeed I think it's relativity that warp speed depends on. Warping space to shrink the distance between points then traveled in less time at the same speed.
Stark Trek Warp Drive makes superficial use of general relativity to explain how it works. But it has the same causality-breaking implications as any method of FTL travel/communication. It doesn't matter how the FTL communication occurs -- warp drive, worm hole, subspace, ansible, or palantir -- from some reference frame you will have appeared to travel back in time. So either causality is wrong, or relativity (as in the principle that there is no privileged reference frame) is wrong.
The enemies of Democracy are
They have mass, that automatically means that their maximum theoretical speed (according to relativity) is some number lower than c. c is the speed of light in an impossibly hard vacuum where there is no matter to interact with. That's why this result is so surprising, it is in direct contradiction to the central idea of relativity, that no massless particle can travel at or above c.
Interesting times ahead.
Help stamp out iliturcy.
My gut feeling is that they set a more precise value to the speed of light. What better than a particle that interacts almost not at all with matter, to measure it?
"The agriculture ministry is not in charge of Gundam" - Japanese ministry official.
"or Else" what?
*Gulp*
It's going to be great when they go through all the work of replicating this only to realize that some janitor moved the detector to the other side of the room so he could sweep behind it and no one noticed it.
Yes, I know neutron detectors aren't something you just scoot out of the way, it's a joke! At the same time, their distance measurement only needs to be off by 6 meters to produce the observed error. I can't imagine that wasn't on their list of things to check though.
Article says that it's compared to light taking the same trip. That would imply it's the speed of light in whatever medium they're using.
They are almost certainly talking about the coordinate distance between the endpoints, and assuming that |x_2 - x_1| / c is the light travel time. (Where |x| is the magnitude of a vector and x_1 and x_2 are the position vectors of the endpoints. Now, it isn't (see my post below about relativistic coordinate systems) but that effect is picoseconds, not nanoseconds.
(Note : They may just be doing this for the press, but it is a common mistake in any case.)
... I want my warp drive.
Obi-Wan: "I felt a great disturbance in the Force, as if millions of voices suddenly cried out in terror and were sudden
That scale factor has been tested to much better than 5 orders of magnitude.
Since the neutrinos do not interact with the medium at all, it will be the speed of light in a vacuum.
If you have faster than light travel, you can have causality violations. (In other words, you could prevent your own birth, change history, things like that.) True, it might require sending neutrino detectors off at a substantial fraction of the speed of light, but what is that compared to messing around with the course of history, not to mention the stock market and the pool on the Super Bowl ?
IIRC (it's ben quite some time since I was a trekkie), warp drives work by tunnelling through subspace.
Basically, you flip the ship into another universe with different rules, create a field around the ship to maintain our universe's properties inside (force strengths, planck length, c, etc.), and move your field (the "warp bubble") and its contents to the location in subspace that matches your destination in our universe. Then you "come out of warp" - i.e. you flip back into our universe - and you're there. The reason warp isn't instananeous is that you actually have to travel spacially inside subspace.
There's probably some explanation as to why subspace radio works "instananeously". By the time I knew enough about relativity to know how rediculous that is, I wasn't a trekkie anymore.
Anyway, warp drives don't violate relativity because they go around the problem. They do violate causality, however, but that never seemed to come up in the show.
What you're talking about sounds similar to the Alcubierre Drive. It requires the ability to manipulate the contraction and expansion of space to work, which may be possible in a theoricial sense, but no one has a good practical idea of how to do it.
Those who can't do, teach. Those who can't teach either, do tech support.
ur mum's face are an ass.
cower in my shadow some more behind your chosen act of loosening based pseudonym, feeb.
you're completely pathetic.
Are loosening based pseudonyms more feeble than other pseudonyms?
Now I can play lagless counter-strike with my mates in Japan who use fiber.
Or it was a computer that used a (int) cast on the result.
Which direction are neutrinos traveling in reference to the earth's rotation? Could something like that affect the results? I imagine it's the same (on a very tiny scale) as to run down in electric stairs that are going down. Let's see: http://g.co/maps/m8wky. I'm curious can anyone elaborate?
Also, thats awfully close to the earthquake struck city of L'Aquila, I hope no Italian get this news because if theres a quake there in the following days the CERN scientist risk getting charged with manslaughter :/ for "debunking theories of death scientist that unfolds the wrath of Hades causing earthquakes"
I'm sure the universe have the likes of a "Galactic TSA" You think anal probes were exaggerated? You don't want to know what the Galactic TSA can do to protect the universe from the plague.
oops, my bad. Laser rangefinders measure the round-trip reflection. Infrared rangefinders typically use triangulation. I assumed (wrongly) that infrared rangefinding worked the same way as laser rangefinding.
The PIC24F series has a CTMU which is very useful for measuring time periods 1ns on a processor with an instruction clock running at 16 MHz. When the first pulse goes out, it starts charging a capacitor with a constant current. When the reflection pulse returns, it stops charging the capacitor. And ADC then converts the collected charge's voltage into a digital value which is proportional to the amount of time it took for the pulse to return.
:(){
Slaver stasis shields.
And maybe neutron stars.
Yes, but in your example, an observer in the frame of reference of the neutrino itself would be traveling faster than the speed of light. That frame of reference would be going backwards in time.
It's my understanding that nothing can *accelerate* to the speed of light; it's generally theorized that things like Tachyons can go faster.
The official announcement will be only tomorrow:
http://indico.cern.ch/conferenceDisplay.py?confId=155620 ...and yet the news wires are already there.
You need to hand yours in as well... the technobabble you are thinking of is the chroniton particle.
THE SOFTWARE, IT NO WORKY!!!
Well, that is a good catch and very interesting.
Minos found an estimate of
(v c)/c = 5.1 ± 1.2 (statistical) ± 2.6 (systematic) / 10**5
where statistical and systematic are their estimates of these two different types of errors. Compare this to the current estimate of
(v c)/c = 2.5 ± 0.4 / 10**5
Note that both experiments found v > c. While I still think this is a systematic error, the fact that two groups found similar v > c for neutrinos make it seem a little more likely.
but they are closing in the next few months.
high-frequency trading of course
fifteen jugglers, five believers
'when you take away the impossible what you are left with, no matter how improbable, must be the truth.'
Einstein may have been mistaken, it could be that the speed of light, like the speed of sound so many decades previously, can in fact be broken, and all the effects that Einstein theorised are in fact just causalities to do with what in fact would be 'seen' by an observer, as opposed to what would actually be happening in 'real time' as it were... as the object would be moving faster than the light it would be producing, it would be unable to be observed in any 'normal time' frame and would appear to observers to slow down and stop, and even move backward in time as it broke its own 'light barrier'. This is only a hypothesis of course, based on my rather small understanding of the effects...
M
-Magdalene --"there are 10 types of people in the world, those who read binary, and those who don't"
What if the maximum speed in the universe was the speed of the Neutrino (N), and that photons just happened to travel at 99.9999% of N? Perhaps general relativity is correct, and the Lorentz equations work, but instead of Sqrt( (1 + V/C) / (1 - V/C) ) it is Sqrt( (1 + V/N) / (1 - V/N) ). If C and N are sufficiently close, it would explain why we haven't noticed the difference before. This would mean that casuality wouldn't need to be abandoned; space/time diagrams would just be based on the speed of the Neutron instead of Light.
By the way, I know everybody at CERN is both smarter and more knowledgeable than I. I'm just having fun.
Considering differences in altitude, oblateness of the Earth, the detector is underground, and so on, it isn't hard to imagine an 18m position error over approximately 732,000 m distance measured or calculated.
Considering that the world's longest tunnel is 57 km long and they drilled it from both ends and the error when both ends met in the middle was about a half meter, one gets an idea of what's the attainable precision.
If they used the same level of precision, scaling up the error would result in a 6 m error at 732 km. However one must take into account that in digging the railroad tunnel they only went to the precision level they needed for that job, one must assume that the scientists used more precise methods.
So, it's very hard, practically impossible, to imagine that there would exist an error of 18 m in the position of the detector.
Break out the Kosinski scale!
Paul: Father... father, the sleeper has awakened! - Dune
How sure are we that the speed of light in vacuum is really the maximum speed of light? One random idea that comes to mind: What we consider vacuum might not be as empty as we think, it might be filled with some kind of dark matter. Light traveling through matter is slower then light in a vacuum. Thus light traveling through our not-quite-vacuum is slower then the actual speed limit of the universe. Neutrinos might not interact with dark matter and thus get a little closer to whatever is the absolute speed limited is. The problem would thus not be that C is wrong, but just that it's a little bigger then assumed.
Of course that's just a crackpot idea, I have no idea what I am talking about.
FFS, nothing personal, but could you people stop trying to explain complex physical phenomena with your "gut feeling"?
Here http://en.wikipedia.org/wiki/Time_travel#Via_faster-than-light_.28FTL.29_travel , read it, comprehend it, think twice next time before post something. Tl;dr FTL = time travel in context of SRT.
Mods: You are welcome to mod me down for my bm, but I really had enough with this whole discussion...
The speed of light in a vacuum is the same. The speed of light in a material is slower than the speed of light in a vacuum and is quite possible to exceed.
Angry Physicists, that do not accept anything can be faster than light, clogging the post with comments in 3 ... 2 ... 1 ...
(I am of those who believe that everything can be revised if you show sufficient evidence)
Religion: The greatest weapon of mass destruction of all time
"Visible" light tends not to travel through 'the ground' very well.
Fixed that for you.
When people say 'compared to light taking the same trip' they generally don't mean radio waves or gamma rays.
I'm guessing they used a laser to calibrate the experiment; if that's the case then the actual distance is nearly irrelevant.
If you're not part of the solution, you're part of the precipitate. ~Henry J. Tillman
I thought it was also based off of being absorbed and getting retransmitted or is that more or less the definition of refraction index?
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.
And since REM just announced that they are disbanding, I can't help how prescient one of their signature songs is: "It's the end of the world as we know it...."
Sure, but my GP's question was:
So I think it's a valid question, right?
Visit the
...and makes some lucrative stock transactions
I love how every AGW story is filled with comments like "you're not a climatologist, so you're not qualified to question the results", but this story is filled comments from armchair physicists telling the people at CERN why they're wrong.
worm hole ... So either causality is wrong, or relativity (as in the principle that there is no privileged reference frame) is wrong.
How does an EPR bridge figure in?
My God, it's Full of Source!
OUTSIDE_IP=$(dig +short my.ip @outsideip.net)
So, Einstein was wrong. Big deal. I've been telling people that for years. The rules in the third dimension don't necessarily apply to that which exists in the fourth. Of course, there is the remote chance those particular neutrinos are from the same experiment 10,000 years from now... Where, exactly were those neutrinos made? Did they lose any information?
There is nothing to FEAR but NOTHING itself; and I fear there is a whole lot of nothing going on. --scorpivs
Alternate explanation (and only slightly fantastical).
What if spacetime warped in the vicinity of the LHC? That would bring the two points closer together, thus the neutrinos actually were only going light speed (or overwhelming fraction thereof).
-nB
whois gawk date unzip strip find touch finger mount join nice man top fsck grep eject more yes exit umount sleep dump
Another incredible, mind-boggling possibility: measurement error -- the particle did not exceed the speed of light.
Currently hooked on AMP
c has been measured very very accurately by independent teams...it's not likely to be the source of the error.
Are neutrinos susceptible to the weak force?
Would subtracting the effect of gravity onto photons account for the difference?
Everyone else is covering that angle.
I wanted to explore something cooler.
whois gawk date unzip strip find touch finger mount join nice man top fsck grep eject more yes exit umount sleep dump
I know you are i said you are but what am i.
i spent five minutes thinking and all i got was this crappy sig
Indeed. Using rtklib you can get 10 cm accuracy even with two cheap openmoko phones (~200 EUR) and cheap antennas (~20 EUR): http://lindi.iki.fi/lindi/finhack/finhack2010-rtklib-lindfors.pdf -- you can read more about it on foss-gps mailing list.
I, for one, have had it with theses so-called "Relativity Deniers." The science of relativity is settled ! The consensus has been for over 100 years that the speed of light is absolute ! These 'Deniers' are the result of Right-Wing knuckle-draggers in the Republican Party ! They must be sought out and DESTROYED !!! First there was the reports of sea-level DECLINE, and now THIS ! Is NOTHING sacred??? BY the great god ARCTURUS, I swear that AlGore(tm) will be avenged !!!
How do you measure distance to a meter with surveying when the ground moves a good portion of that due to tides alone? How about techtonic drift.
I mean, these are long distances through the mantle, and even if you had a ruler and a tunnel to run it through you'd have to deal with huge amounts of sag.
Sure, it can be done, but you could probably argue endlessly about systematic error. The only way I could see it working is if you somehow sent photos alongside the neutrinos so that you could measure the relative speed.
Here is a prediction : Some theorist will come up with a theory (probably involving neutrino oscillations) explaining why v > c is only observed at short range, and the effect vanishes and v->c over distances like 160,000 light years. For bonus points, the short range of the effect will make it impossible to use it for causality violations.
A few people do have an idea of how to make such a "drive" work, but the amount of energy required is downright silly. As in our entire sun might not create enough power. I can't imagine what would happen if such a theoretical drive blew up. "Sir, we have a problem with the engine..." (entire solar system vaporizes in a supernova).
Anyways, none of this violates anything (obviously the universe didn't explode or anything). Einstein was simply wrong. As many, many physicists have suspected now for a long time. Of course the math required to explain all of this new information, well, that might take a very very long time to work out. I suspect that human minds won't ever get such a "unified theory" done. But AI might some day.
I wanted to explore something cooler.
Knock yourself out! :-)
Currently hooked on AMP
You're off by a "k"....
Don't you dare outbid me!
Mostly random stuff.
Not if they're surfing neutrinos, evidently! :)
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make install -not war
Man, wouldn't it suck if the FERMI team found this but shrugged it off as just a statistical fluctuation, then CERN team gets all the credit?
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.
Maybe they measured the distance between two points using kM instead of KiM which leaves them off by about 24 meters per kM...
Just when you make it idiotproof, some idiot builds a better idiot.
From analyzing gamma, wouldn't a speed greater than light imply the neutrino has either imaginary mass or imaginary energy?
If only physicists were used to using a language that often did implicit casts...
The universe not having blown up isn't necessarily a sign that the drive doesn't violate anything. It could just as easily be a sign that there's no way to actually make a working version of it. Requring the energy equivalent of the total converted mass of a star or three is a major barrier. That's what I meant by "no practical idea".
We don't know Einstein was wrong yet - the whole drive thing is theory, and there isn't even a consensus on how to accomplish such a thing. Even if aliens figured it out somewhere, causality violation might not cause the universe to blow up. Either way, relativity is a working model which works really well when applied to certain tasks, but we already know it fails in certain areas (hence quantum mechanics).
Being "wrong" doesn't really make sense anyway - we already know of places he was wrong - hence quantum mechanics. That doesn't stop us from using relativity for a lot of things, just like how we still use Newton's laws for the vast majority of applied physics.
Those who can't do, teach. Those who can't teach either, do tech support.
Doesn't anyone know what this means?! We've found the cure for all of life's problems! Just send a Tachyon beam at it and bounce it off the deflector dish! Thank you Star Trek for solving all of life's problems for us! Now bring out the green women!.
Disclaimer: Liberal Arts graduate. Knowledge of modern physics limited to reading snarky comments of slashdotters nitpicking sci-fi that fails to account for relativistic effects.
http://arxiv.org/abs/1109.4897v1
If an object were to have truly no mass it wouldn't be bound by the same speed limits as normal matter.
Actually, according to relativity, objects with mass must travel slower than light and objects with no mass must travel at the speed or light. No more, no less.
And of course, if you're into tachyons, objects with imaginary mass (whatever that physically means) must travel faster than light, and cannot slow down to the speed of light or below.
from TFA at http://arxiv.org/pdf/1109.4897v1 regarding the time and distance measurements:
time: "A key feature of the neutrino velocity measurement is the accuracy of the relative time tagging at CERN and at the OPERA detector. The standard GPS receivers formerly installed at CERN and LNGS would feature an insufficient ~100 ns accuracy for the TOF measurement. Thus, in 2008, two identical systems, composed of a GPS receiver for time-transfer applications Septentrio PolaRx2e [16] operating in “common-view” mode [17] and a Cs atomic clock Symmetricom Cs4000 [18], were installed at CERN and LNGS (see Figs. 3, 5 and 6)."
and "The difference between the time base of the CERN and OPERA PolaRx2e receivers was measured to be (2.3 ± 0.9) ns [22]. This correction was taken into account in the application of the time link."
So time measurements at the emission and detection sites seem to be correlated to within a few nanoseconds, at most.
distance: "The other fundamental ingredient for the neutrino velocity measurement is the knowledge of the distance between the point where the proton time-structure is measured at CERN and the origin of the underground OPERA detector reference frame at LNGS. The relative positions of the elements of the CNGS beam line are known with millimetre accuracy. When these coordinates are transformed into the global geodesy reference frame ETRF2000 [24] by relating them to external GPS benchmarks, they are known within 2 cm accuracy."
Distance measurements between the emitter and detector appear to be known to within an uncertainty that would be sub-nanosecond at c.
TFA gives the clear impression that a lot of skull sweat has gone into "checking the measurements", and there's a residual anomaly. Props to these folks for putting their work out where the world can see and criticize.
In 1987 there was supernova (SN1987A) in the large magellanic cloud which produced a burst of neutrinos in time with the light becoming visible (at least to within some hours accuracy) as seen in several detectors on earth.
A (very!) rough back of the envelope calculation would suggest that if the claimed effect is true of all neutrinos this neutrino burst would have been ~years earlier although the energy of the neutrinos is lower for an SN than an accelerator. So I'll need some convincing as to why these neutrinos did very clearly NOT travel faster-than-light. Since neutrinos barely notice ordinary matter it can hardly be a tunneling effect (which can make particles go FTL but not information) and the only other differences are that OPERA has muon, not electron neutrinos (at source) of a higher energy.
Details: CERN to Gran Sasso is O(10^5 m) and gives an O(10^-8s) time gain so the LMC is O(10^21m) away so, if the speed is the same, I'd expect an O(10^8s) time gain which is several years whereas they were observed in time enough to make the measurement one of the most stringent limits on neutrino mass at the time!
What an interesting conversation :-)
Slipping shoelaces ?
Faster than C I guess
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.
http://msevior.livejournal.com/30816.html
SETI has been wondering why we don't hear from any other life forms that exist out there, but if there exists some means to send information faster than the speed of light, why would any aliens limit themselves to the EM spectrum? If this proves to be accurate and available as a means to send information FTL, then we may have been looking in the wrong place all this time.
A part of me hopes to throw out all of my physics books, just on the off chance that the universe may not be as quiet as it looks
I"m the last person who should bring this up as
everything I know about it is below.
At one time "stuff" could travel FTL.
The great expansion of the universe just after the big bang
wasn't possible without "stuff" traveling FTL.
I mentioned this and was told that the "stuff" could travel FTL
as it had no information.
I shook my head knowingly and left it at that.
----
So this "stuff" traveled (expanded) then obtained information, I see a similarity
with the neutrino changing into something else.
True. I was going to mention the same thing applies to Newton, but I thought that it was kind of obvious.
But it is neat how what we know to be true is being seen at work/in person. That is, that what is considered "the law" is merely once again just a basic step in something else or a more advanced theory. It's like how we went from flat earth and the earth at the center of our solar system to a round earth. Well, mostly rond - it's now *quite* round if you want to get technical. And so on and on it goes... So when I hear someone say something like "nothing can go faster than light" as if it's the World of God, well, it just sounds silly, given how painfully little we know about how the universe actually works.
But it is good for the "basic" stuff, as you put it ;) (which is more advanced than 99% of the people, even here, can deal with)
My assumption has always been that photons travel at c no matter the "medium" because there isn't really a "medium" per se, just collisions with things that occupy space.
I'm just a dreamer, though. I know nothing of physics.
How does an EPR bridge figure in?
I have no idea how an actual wormhole would work out. I just know that going faster than light according to some reference frame -- even if you take a geometric shortcut through space-time to do it -- ends up looking like time travel in some situations.
The enemies of Democracy are
This isn't the first time some neutrino experiments indicated an imaginary mass.
A 1993 article
But other experiments indicated an ordinary (yet tiny) neutrino mass.
Another article
A third article
The neutrinos were moving faster than the measured speed of light in vacuum. This is very interesting. We assume that the speed of light in vacuum equals the maximum speed for the transmission of information. That is not _necessarily_ true since vacuum contains quantum fluctuations, dark energy and other quantum effects. In this case "c" would only be an approximation for the maximum speed for the transmission of information. Proposed Explanation: the speed of light in vacuum (c) and the observed neutrino speed are both less than the maximum speed for the transmission of information ( c++ ?).
How does one accomplish nanosecond resolution timing between two systems over such distances?
All particles with positive mass go slower than the speed of light.
Particles with zero mass go at the speed of light.
Therefore these neutrinos, going faster than c, have negative mass.
Negative mass, plugged into gravitational formula will give repulsion rather than attraction.
If the universe is filled with these neutrinos, it would explain the repulsive force we label as dark energy.
Would someone explain what is wrong with this reasoning?
This is different. Unlike global warming, for which there has been no recorded rise in global temperature since 1998, this actually has observation backing it.
You are an idiot.
You mean these observations?
Or are you picking your cherries from somewhere else?
Watch this Heartland Institute video
If could have sworn that in Trek they used the warp engines to partially shift the ship into an alternate universe (subspace) where the speed of light was very different.
The world you experience is only a close approximation of reality.
In the Starfleet Technical Manual it diagrams the space warp in which the ship can move through less space between points than without the warp.
But it seems that there's room in there for a subspace entered by warping space.
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make install -not war
There has been a long debate about the anisotropy of the speed of light. The current orthodox belief is that it is isotropic, but I have yet to see a convincing proof. What would the CERN neutrino experiment tell with another detector elsewhere?
Maybe their computers are er.. bit out of date? You know, that old like first Pentium chips? :) http://en.wikipedia.org/wiki/Pentium_Bug and this is the explanation of this 60ns error.
I read here and there that if this research is valid this could make time travel possible.
Is that just hyping?
If not, could anyone explain how this would work in understandable language to those of us without a physics degree, but very interested on an amateur level.
I know that the closer you get to lightspeed the slower time goes and a particle like a photon that travels at the speed of light has no mass and for that photon time stands still.
In looking for possible explanations, isn't it possible that this could be a nice twist towards String Theory? If we assume extra dimensions curled up inside the 3 spatial dimensions of our own + time, isn't it then possible for a neutrino to pass trough a curled up dimension and 'tunnel' it's way to the end point e.g. kind of wormhole?
Also, what was the mass of the neutrino when it went past light speed? Should have been infinitely big.
> Gran Sasso laboratory
I see, I see. A small commando of german neutrinos arrived through the air unexpectedly early at the Grans Sasso and liberated the Duce. Maybe if the researchers told those neutrinos to use the cable car instead of an airplane, the results would be equal to the expected value and do not up-end the jewish science of relativity.
You can download the actual paper by the OPERA collaboration here: http://arxiv.org/abs/1109.4897 They have measured the distance of 730km to an uncertainty of 20cm using GPS and a dedicated geodesy campaign. Of course, when they talk about their six sigma result, this uncertainty is already included. If this turns out the be a fluke, it will most certainly not be because they messed up their distance or time measurements in a trivial way.
Perhaps the speed of light is the upper limit but some effects are seemingly outside its jurisdiction?
Quantum physics gives me a serious boner.
You need to hand yours in as well... the technobabble you are thinking of is the chroniton particle.
Yes, but don't chronitons decay into energons and megatrons?
The world you experience is only a close approximation of reality.
this is the duplicate post, the original will follow shortly
I sat down to write a new sig tonight and all I did was make the chair warm.
FTL != backwards time travel.
According to relativity it is. If you can send a message faster than light, you can take advantage of time dilation effects when moving at a high relative speed.
sounds quite normal indeed: neutrinos use C++ :):)
Stupid question - but did they account for the curvature of the earth?
The GPS, and Radio signals would give a surface distance between the two points
but presumably the neutrinos went as the crow flies - through the crust, 732 km is well over the horizon.
"The superluminous speed obtained with a laser (acting upon rubies in series previously charged) has demolished the Einsteinian myth of the maximum speed (300.000 Km/sec) reaching up to 2,700.000Km/sec, that is, exceeding the "limit" nine times. These experiences were accomplished in 1967 in the laboratory of quantum radiophysics, the Lebedev Institute of Physics of the Academy of Science of the USSR by N. Basov (Lenin and Nobel Prizes), I. Zubarev, V. Efinkov and A. Grasik. This 'jump in octave' of the speed of l. will surely revolutionise the concepts of today's Physics." http://www.nobelprize.org/nobel_prizes/physics/laureates/1964/basov-bio.html
Could it be that miniature black holes have formed somewhere along the path of the beam? those miniature black holes may have deformed the space in the path of the beam in such a way that the neutrinos arrived earlier, because they actually traveled a shorter distance.
Here is something that struck me - in that whole, huge, author list I did not see a single geodesist or clock comparison person. (I can't claim to know them all, but I did work in those fields and do know most of the major players, plus their institutions.) If it were me, I would have brought in an expert in both GPS geodesy (there is a strong group in Switzerland, and another in France, not to mention Italy) and clock comparisons (several strong groups in France) as co-authors before I published the paper.
Neither geodesy nor clock synchronization are trivial at the accuracy they are claiming over the distances they used - true, fairly routine now-a-days, but not trivial. Since the whole paper hangs on that, a few practiced eyes from those fields could not have hurt.
Einstein discovered relativity by using educated gut feeling, not experiments.
unfinished: (adj.)
I think that the best proof of this would be to perform time of flight measurements around a triangle. This is commonly used in interferometry, as many errors (such as geodetic errors and clock errors) will "close" around a triangle, but the actual time of flight should not.
This is called the Sagnac effect, and is due to special relativity and the motion of the observers during the observations (it used to be called "retarded baseline" in VLBI). Now, an equilateral triangle with 700 km sides would only have a non-closing delay of 0.7 nanoseconds, which is too small, but one with 4500 km sides (roughly the US to Europe to Japan) would have a non-closing delay of 29 nanoseconds, which they could detect.
Handling speeds which are that near to the speed of light without regarding the relativity is quite far from "educated".
Colonel Sandurz: Try here. Stop.
Dark Helmet: What the hell am I looking at? When does this happen in the movie?
Colonel Sandurz: Now. You're looking at now, sir. Everything that happens now, is happening now.
Dark Helmet: What happened to then?
Colonel Sandurz: We passed then.
Dark Helmet: When?
Colonel Sandurz: Just now. We're at now now.
Dark Helmet: Go back to then.
Colonel Sandurz: When?
Dark Helmet: Now.
Colonel Sandurz: Now?
Dark Helmet: Now.
Colonel Sandurz: I can't.
Dark Helmet: Why?
Colonel Sandurz: We missed it.
Dark Helmet: When?
Colonel Sandurz: Just now.
Dark Helmet: When will then be now?
Colonel Sandurz: Soon.
[http://www.imdb.com/title/tt0094012/quotes]
- Sig
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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It's been done since the 1970's (Viking lander range measurements to Mars in 1976 were good to about 7 nanoseconds).
Now-a-days, really accurate delay measurements are at the picosecond level (Lunar Laser Ranging now can be done to a few picoseconds). GPS receivers do 50 nanosecond time delays with equipment that can fit in your phone.
As others have said, it's a matter of having fast enough electronics, and a fanatical attention to sources of error.
Nope. The refractory index of a material is a ratio between the speed of light in the medium and the speed of light in air. Also, "light" does not necessarily or generally mean the visible portion of the electromagnetic spectrum. Most materials are transparent to at least part of the spectrum, so the local speed of light is applicable even to materials which are opaque to visible wavelengths.
Light is also affected by gravity, although this may be because space/time is warped by the gravitational field and from the photon's frame of reference it is traveling in a "straight" line. Only from an outside observer's frame of reference would its path appear to be curved. I personally think that this is also probably the most likely explanation for why the speed of light changes in non-vacuum... the strong fields generated by proximity of mass on an atomic scale curve or compress space/time within the material.
You can't decelerate continuously across the speed of light - the only way you can ever be travelling at exactly the speed of light is if you're massless, and then it's impossible to accelerate or decelerate you, at least according to our current understanding of physics.
I am trolling
You can bet some people at Fermilab are looking at some old data really carefully this morning.
Educated reasoning, not gut feeling. His famous thought experiments are very rigorously thought out - which is why they work.
I am trolling
now that really is funny!
True, if they could send light down the same route, this would make sense. However, from the lab's website:
The average 1400 m rock coverage gives a reduction factor of one million in the cosmic ray flux...
So they'd have to dig through somewhere between 1.4 and 732 km of rock to do this, which probably makes this impractical.
"Money is a sign of poverty." - Iain Banks
Or it was a computer that used a (int) cast on the result.
Yeah, or their fucking abacus ran out of beads.
To have a right to do a thing is not at all the same as to be right in doing it
I don't just play one on the Internet.
Graduate school at UC Santa Cruz didn't work out as a result of my mental illness, but the people at the Physics department there made it clear they wanted me back after I recovered from getting profoundly paranoid over the fact that North Korea was caught building a nuclear reactor during my second quarter of my first year. A-Bombs aren't really that hard to build; while it takes a lot of cash and a big industrial plant, some US Government committee, in its infinite wisdom, declassified most of the Manhattan Project secrets in 1965. The only still-classified secret is the Plutonium Implosion Bomb's initiator. Spending too much time thinking about World War III and trying to warn the world about it put me in the Dominican Mental Health Unit twice that Spring.
While I never made a career of it, I have some papers in the Astrophysical Journal and Physics Review Letters B. I wrote my UCSC undergraduate thesis on a US Energy Department grant at the Spin Muon Collaboration's facility on the French side of CERN during the Summer of '93. Most UCSC students have to stay on campus to research their thesis, but my advisor Clem Heusch said I had unusual potential.
Clem was looking for Non-Conservation of Lepton Number by using the SMC's Muon beam and highly magnetized Liquid Helium target to look for a Muon going in, scattering off a nucleon (or, more precisely, one of the quarks that make up a neutron or proton), then leaving the interaction having been changed into an Electron or Positron. This would be a violation of one of the most fundamental Laws of Physics, but for reasons I was never really able to grasp, it is speculated that just this might occur naturally in the Universe. If so, it could contribute to the explanation of Dark Matter and other unexplainable phenomena.
The observation of neutrinos traveling faster than light is exciting and unexpected, but not THAT unexpected. Clem's Muon-to-Neutrino search was part of the whole Physics community's effort to revise the Standard Model. The Standard Model is all of the Laws of Physics put together, with the exception of General Relativity - Einstein's gravitational theory. We don't include Gravity because gravity is such a weak force that we cannot collect enough experimental data for the theorists to produce a Quantum Theory of Gravity.
It has been widely agreed for decades that the Standard Model is quite wrong, but only recently are we beginning to identify just how it is wrong. The observation of Neutrino oscillations at CERN a few years ago by blasting an intense beam of them through a bunch of heavily shielded photographic film, then right down the main street of neighboring St. Genis, France was the first experimental proof that the Standard Model really is incorrect. Collecting more measurements of more oscillations will give the theorists some of the experimental data they need to revise the Model.
Neutrinos were originally thought not to oscillate, but some theorist predicted that if they had non-zero mass, they would oscillate as well. What is really exciing about this latest find is not just that C isn't quite the Speed Limit of the Whole Universe, but that massive objects are exceeding lightspeed!
As to why I posted this comment in reply to the above limerick...
Young Lady Bright's Relativistic Limerick has been my very favorite of all limericks ever since I found it in Clifton Fadiman's The Mathematical Magpie at the Moscow, Idaho public library when I was in sixth grade. The fact that I spent so much time reading that book had a lot to do with my physics degee and my career as a software engineer. It was published in the 1950s, but it was still in print last time I checked several years ago. One of my proudest possessions is my own hardback copy that I found in a used bookstore. There was a card inserted in it that indicated it was meant for a book reviewer, so my partic
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how in the hell is the ratio of mass to energy exactly the speed of light squared?
The same way that the ratio of mass to volume is exactly 1 gram per cubic centimeter of water.
How can we use this experimental result to make a better HFT system :)
I thought it was also based off of being absorbed and getting retransmitted
No. That's called fluorescence. Refraction is completely different.
What we consider vacuum might not be as empty as we think
Forget about dark matter; we already know what it's full of: gravitational fields. Does gravity affect light? Yes it does...
First Post addicts are having a trollgasm over this.
Table-ized A.I.
One of the important properties of neutrinos is that they react very weakly with matter. They can shoot straight through air, stone, metal, or the entire earth without appreciably slowing down or being absorbed or deflected. Light is slowed by physical media because it interacts strongly with matter. It is even possible for ionizing radiation to exceed the speed of light through a medium. When it does it produces Cherenkov radiation, the blue glow we associate with nuclear reactors, which is analogous to a sonic boom. In this experiment, they were shooting the neutrinos at a detector 732 km away, which, due to the curvature of the Earth, would mean angling the emitter down and shooting neutrinos through the Earth's crust. So, exceeding the speed of light through what is basically stone is nothing to write home about.
The neutrinos are claimed to have arrived before light should have, not before they were sent.
Neutrinos and tachyons?
The results of this experiment are very exciting and could open new horizons in physics and our knowledge of the world.
However, before throwing causality, as the baby with the bath's water, we must think much about it and analyze it from a broader theoretical framework.
Some studies already postulate the existence of hypothetical particles, the tachyons, whose speed is always greater than the speed of light in vacuum. This will be allowed formally by the equation of relativity, the famous E = mc ^ 2, Einstein's equation, reformulated with complex numbers. Without going into details, let's say that the rest mass of a tachyon is an imaginary number, while its energy is a real number (http://en.wikipedia.org/wiki/Tachyon)
In addition, some studies suggest that neutrinos could be "tachyonic". As this article from Chodos, 1985. "The neutrino as a tachyon" http://adsabs.harvard.edu/abs/1985PhLB..150..431C
There are still problem with the mass of the neutrino, would be non-zero according to recent experiences... Perhaps, non-zero but imaginary ... Who knows? Let the experts go further!
Regardless, those results fully justify the investment into the CERN's Large Hadron Collider!
Which would be more useful, a perfect EM reflector, or a perfect EM absorber?
You don't break causality, you just have a new speed limit for it. Breaking causality would require something arriving before it was sent, not messages arriving out of order.
At one time, the speed of business was the maximum speed of letters carried across the ocean. Telegraph allowed business communication much faster, so the speed limit of causing things to happen on the other side of the ocean was upgraded - we didn't break the maximum speed of a letter going across the ocean, we found something else entirely that went faster. Telegraph didn't allow messages from the future.
Does relativity really say that neutrinos can't go faster than the speed of light?
What is they mass of a neutrino? Maybe they only sometimes have mass.
No the speed of light is constant. as said before, in something else than the vacuum, it looks differently, but this is an illusion
what is a medium, that is not vacuum ? how is it ? atoms are mostly made out of vacuum
photons don't have some particular 'friction-like' problem when going through any such material
what happens is that, as the electromagnetic wave front 'enters' the medium, it does what it is there for, and it accelerates electrically charged particles if any.
those (electrons in general, mostly bound to their atom) will oscillate in response and create an EM field on their own like new sources
those sources will interfere with the original source and create a new overall pattern that we would call 'this is light traveling in this medium'
This new wave is what can be seen as light going slower than c in this particular medium.
Einstein discovered relativity by using educated gut feeling, not experiments.
No. Einstein made use of Maxwell's equations to deduce that the speed of light was constant under all reference frames. The second order PDE equations relating the time variance of the electric field to the spatial variance of the magnetic field has the speed of light as a constant. He didn't have a gut feeling.
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.
I'm not sure I buy that explanation. To appear to move slower than C, the interference would have to exactly cancel out the light for
t >= distance / C,
t < distance / speed of light in medium
and have exactly zero effect on the light for
t >= distance / speed of light in medium
Or in other words - if the first photon leaving the medium isn't the first photon that entered it, what happened to that photon? Why doesn't the same thing happen to the rest of the photons that enter the medium?
Anyway it would mean that transparent objects transmit light in much the same way as fluorescent objects fluoresce - which leads to all sorts of other questions, such as why in one the angle of light leaving is related to the angle of light coming in, but in the other the light leaving it is diffuse; and in one, the light produced is different in phase but in the same wavelength, but in the other the wavelength is different.
for picking this apple?
No the speed of light is constant. as said before, in something else than the vacuum, it looks differently, but this is an illusion
Light also travels in straight lines, but in a gravitational field you'll observe the illusion of light appearing to curve.
atoms are mostly made out of vacuum
So is a gravitational lens.
those (electrons in general, mostly bound to their atom) will oscillate in response and create an EM field on their own like new sources those sources will interfere with the original source and create a new overall pattern that we would call 'this is light traveling in this medium' This new wave is what can be seen as light going slower than c in this particular medium.
I don't buy it. See elsewhere for my response to that theory.
We have to find Zephram Cochrane! Before they get here!
If you can read this, I forgot to post anonymously.
Yeah, I had the same thought. Perhaps solid stuff (the earth) displaces 'null' space (see Casimir effect) and photons would actually go through faster if they weren't being blocked by the mass.
love is just extroverted narcissism
This lady was Bright but not bright : the next morning she again joined that flight : So then two made the date : and then four, and then eight : And her spouse got one hell of a fright!
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I am sure they have thought of this and corrected for it, but I thought it might be nice to point out that there is a big difference between a straight line (say like in a beam of neutrinos), and some arbitrary (732km) distance on the earth, which is of course curved.
For all those people talking about the accuracy of GPS, sure when talking about positions on the surface of the earth, however the distance would be different if you are going through the earth in an absolute straight line. Sure the curve of the earth isn't that great, even over a distance of 732km, but it is probably enough to cause 18m of error (or 0.018).
EVEN if they corrected for the curve of the earth, you are likely using an equation that describes the curve as a constant, not as an irregular lump which is what the earth actually is. So unless your equations are taking into consideration the ACTUAL deformity that is the curve between those two points, error may occur.
When you are talking about such small margins of error of "billionths of a second", I'm going to go out on and limb and say one of the first things you should be checking is how accurate that measurement (or calculation) really is.
That is ridiculous. That would require that someone will name their son Zefram 21 years from now (2032).
My money is on an error in the use of a Gaussian function and Monte Carlo simulation to explain most of the bias. A software bug maybe?
But mass travelling AT the speed of light would be!
We had a physics guest lecturer back in the early 80's that predicted something like this, wish I could remember her name. If neutrinos are solitons and interact with nulcei as solitons, then the neutrino that leaves the nucleus leaves the instant the other neutrino arrived. Sort of like when one billiard ball strikes two balls in contact and the second ball flies away. The nucleon density of the earth would determine the percentage of the distance that would be 'skipped' when transisting the earth. An idea of this factor can be obtained by looking at the silicon atom. The ratio of the radius of the silicon nucleus to the size of the silicon atom is about(3.7x10^(-15)) / (111x10^(-12)) or .00034%.
The speed of light in a vacuum (c) is a constant. The speed of light in a non-vacuum is not.
You're right, but I'd like to expand on what you're saying to clarify for all the people that seem not to get it.
Basically, it's just a problem of "really bad naming". Generally speaking, when a physicist uses the term "speed of light", he's thinking "c". "c" has nothing to do with the amount of time it takes for light to get from A to B. It just happens that light going from A to B in a perfect vacuum does so at "c" (due to the properties of light).
"c" is a value that can basically be described as a kind of "infinite speed" in that anything going at that speed would experience no time whatsoever and would therefore get anywhere instantly from their own perspective (it takes some time from other people's perspectives, but that's beside the point here).
So, when you hear "speed of light", you shouldn't think about someone getting out there and measuring how fast light is going in the same way you might imagine when someone says "speed of a Ferrari". Instead you should think about it as being the fastest that can exist in the same way as the north pole being "the most north there is". Going "north of the north pole" isn't just "hard to do", it's impossible because it's meaningless - in the exact same way, going "faster than the speed of light" is impossible because it's meaningless - "c" isn't just a rule about some kind of speed limit, but rather a part of the definition of the concept speed in and of itself.
So, "going faster than the speed of light" is as impossible as going "north of the north pole". What does this mean for this CERN experiment? Well, either there's a measurement error somewhere, or our entire understanding of physics is going to need some serious modification - as much confusion as finding out that you really CAN go north of the north pole.
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WHY IS B'b'bzeee the only one doing this?!
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are we measuring the distance above ground, but the measurement is of under ground distance? in a sphere (earth) the outside is longer than the core. probably too obvious, but figure i would ask.
The difference between NASA and CERN: NASA: ZOMG WE FOUND ALIENS [when ONE person MIGHT have found life that subsisted on arsenate ONCE] CERN: Hey guys... We might have found a particle moving faster than light... Maybe. Want to check our work? We tried it a few (thousand) times, but we might have made a mistake somewhere. (PS If true this will upend a century of physics.)
Look at Figure 7 in their paper - http://arxiv.org/ftp/arxiv/papers/1109/1109.4897.pdf
They see (and account for) both continental drift and the L’Aquila earthquake.
Looks accurate to me. There was an experiment, and it indicated faster than light neutrinos. It's likely to be wrong, and the scientists involved have admitted as much, but they're asking others to conduct the same experiment in an attempt to replicate or refute the result.
The evidence is far from conclusive
If the headline said 'CERN experiment conclusively proves faster than light neutrinos' you'd have a point there. "indicates" is fair enough.
I do not want your cheap brainburning drugs. They are useless for work. And I am a working man today.
They certainly didn't move on to "Hawkings" (Hawking). Hawking turned out to be wrong (and accepted as much) about the consequences for information when dealing with black holes. His big success was hawking radiation, i.e. the tenuous radiation from a black hole's event horizon due to virtual particles falling into the black hole allowing their partner to escape and carry away energy and information. He made an important contribution but next to no physicists would mention him in the same breath as Einstein or Feynman.
I do not want your cheap brainburning drugs. They are useless for work. And I am a working man today.
Outside of special relativity, having particles travelling faster than the background speed of light doesn't necessarily introduce causality violations, if the local /velocity/ of light, at that location and moment, in that same direction, is even greater.
Consider the case of a drifting particle falling into a black hole from null infinity. The inward velocity of the particle would be expected to hit v=c at the event horizon, and to continue increasing (unobserved) as the particle continued to fall, to an arbitrarily high multiple of background lightspeed. But the particle doesn't illegally time-reverse, because it never overtakes its own signals (which are falling inwards even faster). So gravitational event horizons provide an example of predicted (censored) super-fast motion, without involving exotica like negative energy-densities. Like Newcomb's old argument against heavier-than-air people-carrying craft, general disproofs of superfast motion are mathematically tidy, but not necessarily physically reliable.
Outside of black hole problems, super-fast motion can be legal if you use a relativistic acoustic metric instead of the Minkowski metric (in an r.a.m., the motion of a particle is associated with a local offset in nearby light-velocities, allowing the particle to move faster than background c without ever exceeding local c).
Relativistic acoustic metrics are fun, and seem to reconcile quantum mechanics with several key aspects of general relativity - they're tentatively used by some people exploring "quantum gravity" options, when modelling Hawking radiation.
... The reason why we don't use relativistic acoustic metrics seems to be partly historical/social: Special relativity got there first and established the Minkowski metric as a standard, and some relationships come out differently with an r.a.m. than they do with special relativity, so we tend to say that unless someone has convincing evidence that says otherwise, the SR version of events is considered to be "canon". And it's difficult for evidence to be considered convincing if it runs counter to one of the best-known scientific theories, so there's a kind of positive-feedback loop in operation.
Mainstream relativity guys tend not to study r.a.m.'s, not because anyone's come up with a logical reason why they shouldn't work, but because they're told that SR-compliance is mandatory for any credible relativistic field theory, and it's generally thought that violations of SR (like particles moving faster than background c) simply don't happen. So other than the quantum gravity guys, almost nobody's been looking at this class of relativity theory, and the QG guys tend to stop at the point where the thing starts to diverge from special relativity.
Short Answer: Yes, if this thing is right, it probably involves rewriting the physics rulebook, and probably junking special relativity, but ... no, the requirement for special relativity was never really as strong as many people seemed to believe. Yes, losing special relativity would be major from a theoretical and social point of view, but no, it's not too difficult to construct a relativistic alternative, if you're prepared to lose the simplifying assumption of flat spacetime.
(So yes, it might simply be a duff experiment. But it's not yet safe or sensible to assume that that's the case).
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I have a theory that predicts FTL: http://amzn.com/B005NLU7OU I try to tell everybody General Relativity is wrong since 2009. Finite Theory explains all phenomenons including the constitution of a black hole. -Phil
"This is the live Webcast from CERN on Friday September 23, 2011. Given the potential far-reaching consequences of the OPERA experiment --- which observes a neutrino beam from CERN 730 km away at Italy's INFN Gran Sasso Laboratory, indicating that the neutrinos travel at a velocity 20 parts per million above the speed of light --- independent measurements are needed before the effect can either be refuted or firmly established, according to a CERN statement just issued. The OPERA collaboration has therefore decided to open the result to broader scrutiny."
http://www.youtube.com/watch?v=ZFz3fJMJ-yA
“Extraordinary claims require extraordinary evidence.” - Carl Sagan
I wouldn't say that if the experiment is verified that SRT or GRT has to be kicked out immediately.
I am by no way an expert on this, but why should the vacuum not have a susceptibility depending on the energy range? For GeV energy range this experiment seems to be consistent with the earlier experiments. SN1987A observations happened in another energy range AFAIU (any experts here?).
So it could be that in the limit in which we measured c up to now (low energies), c is not the c appearing in relativity.
Wouldn't shock me too much.
(AC's comment above was made before the paper was released)
The l'Aquila earthquake shows up very clearly in the results, it was roughly a 5cm shift in the distance between the labs, and the graph shows it so obviously that it's clear they've got at least 1cm resolution. I think any tectonic activity has probably been accounted for here.
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how likely is it that the speed of the neutrino exceeding the speed of light is so close to the speed of light? methinks not likely hence - systematic error as pointed above that closed the matter for me
I like your wording best. I believe thought experiments are a large part of science. Some think it's mostly about fitting models to experiments (that's the easiest part).
unfinished: (adj.)
I just read the paper regarding the experiment with Neutrinos apparently traveling faster than light, and looking at the geometry of the experiment: Neutrinos traveling from West to East through rock in the Earth's crust (i.e. traveling with the rotation of the Earth) and the fact that they are relying on GPS systems with a common view point on a satellite in space, it appears that Frame Dragging might be the cause of the result... Read this Extract from Wikipedia regarding Frame Dragging: "Frame dragging effects Rotational frame-dragging (the Lense–Thirring effect) appears in the general principle of relativity and similar theories in the vicinity of rotating massive objects. Under the Lense–Thirring effect, the frame of reference in which a clock ticks the fastest is one which is revolving around the object as viewed by a distant observer. This also means that light traveling in the direction of rotation of the object will move past the massive object faster than light moving against the rotation, as seen by a distant observer. It is now the best-known effect, partly thanks to the Gravity Probe B experiment. Qualitatively, frame-dragging can be viewed as the gravitational analog of electromagnetic induction." The point is that the Dragging effect happens to differing degrees depending on its proximity to mass. As the Neutrinos passed through the rock (i.e in very close proximity to the rotating mass) there may be scope for an error in the Frame Dragging calculation, especially if GPS assumes signals traveling through space. Perhaps if a similar experiment was carried out on Neutrinos traveling from East to West, rather than West to East, then a travel time of 60us slower than light speed would be recorded, rather than the 60us faster than light speed of the experiment just performed! Regards, Declan Traill
You were rated troll because they accounted for all of the time settings. Clocks that are accurate to within one nanosecond that sync every 1 microsecond.
The possibility for error from timing is less than 6 nanoseconds. Which is accounted for in the margin of error at 10 nanoseconds.
To be fair the most they could possibly say for a margin of error was around 20 nanoseconds and they would be making some large assumptions as to the inaccuracy of some of their most expensive equipment to do so. The neutrinos got there 60 nanoseconds earlier than expected. Therefore the results are STILL significant.
Fair enough, I don't remember it being written in the article but if these are the facts you can't really disagree can you?
-- no sig today
Its not in the article but it is in the linked-to conference that they held at CERN where they went "Look, we would like to publish this, and we're not saying its a discovery just yet, we think this needs more people to look at it."
Then they fielded about 4 hours of questions from some of the brightest minds available and shot them all down.
By "the linked-to conference" do you mean the one that was supposed to have a web stream? I wanted to watch it but couldn't get the stream up from any of the providers...
-- no sig today