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Can Relativity Explain Faster Than Light Particles?

timothy posted more than 3 years ago | from the old-woman-your-lap-for-a-minute dept.

Science 315

gbrumfiel writes "Two weeks ago, researchers claimed particles called neutrinos were travelling faster-than-light and violating the laws of special relativity. But now it looks as though general relativity might be behind the experiment's unusual result. An independent analysis claims that the original experiment, known as OPERA, failed to take into account differences in earth's gravitational field between the neutrino source and the OPERA detector. As Nature News reports, gravity can distort time according to Einstein's theory, and the effect could explain why neutrinos appear to arrive 60 nanoseconds ahead of schedule. The OPERA team is now reviewing the new analysis."

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Now we know why (0)

0racle (667029) | more than 3 years ago | (#37628290)

Now we know why they had to raise the speed of light.

Re:Now we know why (1)

mr1911 (1942298) | more than 3 years ago | (#37628316)

Now it is c+1?

Re:Now we know why (5, Funny)

Anonymous Coward | more than 3 years ago | (#37628372)

c++

Re:Now we know why (0)

Anonymous Coward | more than 3 years ago | (#37628650)

Slightly better than average seller. C+++++ Will semi-enthusiastically buy again.

Re:Now we know why (0)

Anonymous Coward | more than 3 years ago | (#37628328)

That new tollway will bring in jillions!

Re:Now we know why (1)

Anonymous Coward | more than 3 years ago | (#37628724)

But then when in stronger gravity you'll have to slow it down again. It's not just the clocks speeding up and slowing down. The gravity from stars and other massive astronomical objects wouldn't bend light if gravity didn't affect its speed too. The same principle that makes a refracting medium bend light can be used to explain how light bends in a vacuum in the presence of strong gravity.

In other words, c isn't a constant in all cases depending on the frame of reference. At least for now that's my opinion, and there has been an oversight.

I guess the problem would be like having a speedometer that allows you to change the definition of an hour, so you can claim to be going 10MPH when by everybody else's measure you'd be going 100MPH. That's the thing about time dilation. In one frame of reference c is constant, but it's not so in all frames of reference. Relativity is still very much in effect, but needs the definition modified to allow for recursion.

In other words, it's very possible to go faster than light. (It's definitely possible to be faster than light that has fallen into a black hole.) But you'll never be able to measure it's speed changing in a direct manner. It's the time dilation effect which doesn't allow it. (The apparent mass problem also has to do with energy density per unit time. When the unit time isn't exactly fixed - a second isn't necessarily a second - adjustments made for that might allow some seemingly paradoxical things to be done in this universe.)

Re:Now we know why (2)

eyrieowl (881195) | more than 3 years ago | (#37629384)

huh??

The speed of light is constant across all frames of reference. Frames of reference that are moving relative to each other will perceive light generated by the other frame of reference as having a different "clock" (i.e., frequency), but the speed of the red/blue shifted light will be the same in both frames of reference. The speed of light itself does vary across mediums (say, water vs glass vs air vs vacuum), but that doesn't come into play here. Also, they weren't measuring, directly, the speed of the neutrinos. They were comparing the time of the neutrinos' arrival at different sites and they found a difference that was unexpected. However, that measurement depends very much on the clocks being in sync, and this is what TFA is discussing.

The bending of light in a refractive medium is completely unrelated to the bending in a gravitational field, and your conclusion that the latter involves the speed of the light being altered is false.

Re:Now we know why (4, Funny)

idontgno (624372) | more than 3 years ago | (#37629072)

They didn't have to raise the speed of light; they just raised it a semitone.

That's right. The universal constant for the speed of light is c#.

Re:Now we know why (2)

Oswald McWeany (2428506) | more than 3 years ago | (#37629534)

If C# is now the speed of light- does that mean that Java exceeds the speed of light?

Exactly what I was thinking (1)

ebunga (95613) | more than 3 years ago | (#37628312)

Except with all the math half-way worked out.

I'm impressed (1)

roguegramma (982660) | more than 3 years ago | (#37628620)

I'm impressed that you worked it out half-way ..

Re:I'm impressed (0)

Anonymous Coward | more than 3 years ago | (#37629196)

I'm sure relativity can explain that. Something along the lines of someone appearing to be bright, until you hear them speak. See, nothing is faster than light!

Re:Exactly what I was thinking (0)

Anonymous Coward | more than 3 years ago | (#37628920)

Me too, except I didn't work any math out and then went back to surfing the web.

I called it (0)

networkBoy (774728) | more than 3 years ago | (#37628326)

I called out warped space time as the cause. /win

Re:I called it (1)

Z00L00K (682162) | more than 3 years ago | (#37629094)

But if a particle lacks mass - is it still limited by the speed of light?

Re:I called it (3, Informative)

harperska (1376103) | more than 3 years ago | (#37629202)

If a particle has mass, its velocity will be less than C. If a particle has no mass, its velocity will equal C.

Re:I called it (-1)

Anonymous Coward | more than 3 years ago | (#37629358)

So, E = M x C^2

You say that if M=0, it's velocity will equal C ("If a particle has no mass, its velocity will equal C.")

E = 0 x C^2

t.f. E / 0 = C^2

So C = inf? I don't think so.

Re:I called it (4, Insightful)

MozeeToby (1163751) | more than 3 years ago | (#37629492)

E = mc^2 refers to rest energy, it is the amount of energy you get if you convert an unmoving mass directly into energy. Photons, having no mass, have no rest energy by definition. 0 * c * c = 0. E / 0 is undefined, not infinite. Literally the only line of your reply without a significant error is the first one. E=mc^2 has nothing to do with the assertion that massless particles must travel at c, that comes from other parts of special relativity.

Heathens! (-1)

Anonymous Coward | more than 3 years ago | (#37628342)

This is what happens when your heathen science attempts to defy the word of God. Burn in hell!

Re:Heathens! (2)

MachDelta (704883) | more than 3 years ago | (#37628528)

"Beware, you who seek first and final principles, for you are trampling the garden of an angry God and he awaits you just beyond the last theorem."
-Sister Miriam Godwinson

Sorry, everything reminds me of a SMAX quote after i've been playing. :)

Re:Heathens! (1)

Gilmoure (18428) | more than 3 years ago | (#37628844)

Bummed SMAC/X no longer runs on my Mac after Lion update. Am dusting off an old Mac Mini to set up as game machine now. Wish someone would write a new SMAC/X style game. Other than time killers on phone, don't do any computer gaming anymore.

The speed of light (1, Informative)

RCC42 (1457439) | more than 3 years ago | (#37628356)

It's not just a good idea, it's the law.

Re:The speed of light (0)

Anonymous Coward | more than 3 years ago | (#37628430)

I for one will be glad when all the relativity DENIERS are excluded from discussion of what the scientific consensus has understood to be FACT for some time. Can we just require that meritous publication on the topic be peer reviewed in the future?

Re:The speed of light (0)

Anonymous Coward | more than 3 years ago | (#37628730)

i have prepared myself for a possible whooshing sound so here goes...

"all the relativity DENIERS" ???

is there more then 0 of these types of people? i've never heard of such a thing. I mean today not sometime back in the past. Today who actually is denying or against relativity?

Re:The speed of light (0)

tmosley (996283) | more than 3 years ago | (#37629348)

As in climate science, anyone who believed that there are particles that can exceed the speed of light is a "relativity denier". The AC above is merely pointing out the hypocrisy that we are allowed to question relativity, something that has been exhaustively studied for decades by people who WANTED to disprove it (and thus get a Nobel Prize), but we can't question Climate science, where everyone tries to prove that the AGW hypothesis is true (and thus get more grant funding).

Re:The speed of light (0)

Anonymous Coward | more than 3 years ago | (#37629050)

Great, can we also exclude those who don't understand science and doesnt allow rules to be questioned?

Don't mess with the Einstein (0)

Anonymous Coward | more than 3 years ago | (#37628376)

he'll bitchslap you into oblivion

Dear CERN, (3, Funny)

Anonymous Coward | more than 3 years ago | (#37628384)

Nice try.

Sincerely,
Einstein

Re:Dear CERN, (1)

Illpalazzo (2084816) | more than 3 years ago | (#37629156)

Dear Einstein, Our reports of FTL neutrinos may have been premature. It turns out we just sent them 60 nanoseconds into the future. When we get our flux capacitor working, we'll send them back to the correct timeframe. Thanks. Director of CERN

If this is true... (0, Interesting)

Anonymous Coward | more than 3 years ago | (#37628402)

Faster than light is still possible, but now it's due to gravitational effects instead of innate property of neutrinos. It makes finding the Higgs boson more important than ever.

Re:If this is true... (2)

ColdWetDog (752185) | more than 3 years ago | (#37628578)

Faster than light is still possible, but now it's due to gravitational effects instead of innate property of neutrinos. It makes finding the Higgs boson more important than ever.

Don't jumble words and think you know what's going on.

Let me guess - you're in management?

Re:If this is true... (0)

Anonymous Coward | more than 3 years ago | (#37628624)

Actually, the chatbots are just generating random Markov-chain-based sentences from previous Slashdot stories.

and I'm a unicorn.

Re:If this is true... (1)

Gilmoure (18428) | more than 3 years ago | (#37628884)

*golf clap*

Re:If this is true... (0)

Anonymous Coward | more than 3 years ago | (#37628914)

Faster than light is still possible, but now it's due to gravitational effects instead of innate property of neutrinos. It makes finding the Higgs boson more important than ever.

Don't jumble words and think you know what's going on.

Let me guess - you're in management?

Gravitational effects if they are big enough can distort the local light cone at a spacetime event x.
The light-like generators can be "curved" if you go sufficiently far from x, so a timelike vector at x can have an inclination bigger than c. Material particle that travel locally faster than light.

Maybe neutrinos having so little mass can be affected even by the tiny gravitional field (tiny compared to that produced by black holes, quasars, and other relativistic phenomena) of the earth.

Re:If this is true... (1)

Anonymous Coward | more than 3 years ago | (#37629020)

Or stayed at the Holiday Inn Express last night.

Re:If this is true... (1)

Anonymous Coward | more than 3 years ago | (#37628618)

60 nanoseconds seems to be an incredibly large discrepancy to be explained by local gravitational differences.

Re:If this is true... (0)

Anonymous Coward | more than 3 years ago | (#37629232)

Yeah, well, yur mom's an incredibly large discrepancy who generates her own gravitational differences.

Re:If this is true... (0)

Anonymous Coward | more than 3 years ago | (#37629302)

That explains all the DARK ENERGY, amirite?

Re:If this is true... (0)

jimbolauski (882977) | more than 3 years ago | (#37628726)

The particles were moving at light speed but due to earths gravity space was distorted and the neutrinos went straight across instead of traveling in the gravity well. Essentially the neutrinos warped.

Re:If this is true... (1)

Toonol (1057698) | more than 3 years ago | (#37629154)

But the neutrinos would follow the curved space, just like light would. The curved line in warped space-time IS the shortest distance.

Perhaps what they're saying is that the computed distance isn't taking the warp into effect, basically treating space-time as flat in the presence of the Earth. This would cause the distance to be underestimated, making the velocity of the neutrinos appear higher?

I thought they said they took gravitational factors into account, though.

Re:If this is true... (0)

Anonymous Coward | more than 3 years ago | (#37628728)

No... Faster than light is not possible...
The reason the particle "appears" to travel faster than light is because time itself is warped due to the difference in gravity.. In reality, it's traveling at exactly the speed of light.. Again, it's a frame of reference thing.. They're measuring it at both locations, but if you took a different frame of reference you'd see that from the destination's perspective, the particle is actually being sent 60ns sooner than they thought it was and so it's arriving sooner than the speed of light predicts even though it travels at the speed of light.

Re:If this is true... (1)

Shetan (20885) | more than 3 years ago | (#37629106)

In reality, it's traveling at exactly the speed of light.

Don't neutrinos have mass? Can particles with mass be accelerated to light speed? Without reading the article or the paper and not having taken even a college physics class, I would have expected that a neutrino should have been traveling at near light speed rather than "exactly the speed of light".

The OPERA team is NOT reviewing the new analysis. (5, Informative)

Steve Max (1235710) | more than 3 years ago | (#37628406)

They are reviewing their own paper to make their methods clear. FTFA:

"Dario Autiero of the Institute of Nuclear Physics in Lyons (IPNL), France, and physics coordinator for OPERA, counters that Contaldi's challenge is a result of a misunderstanding of how the clocks were synchronized. He says the group will be revising its paper to try to make its method clearer."

Meaning: Contaldi didn't understand how OPERA did it, and thought they had commited a somewhat stupid mistake. OPERA says they didn't make that error, and that they'll rewrite that part of the paper to make this clear. In other words, this is not news at all.

Re:The OPERA team is NOT reviewing the new analysi (2)

blind biker (1066130) | more than 3 years ago | (#37628438)

Mod parent up +5 informative - and thread over.

Re:The OPERA team is NOT reviewing the new analysi (1)

Anonymous Coward | more than 3 years ago | (#37628526)

They actually answered the clock questions on the first video conference feed the day after the press release.

Re:The OPERA team is NOT reviewing the new analysi (2)

Fred Ferrigno (122319) | more than 3 years ago | (#37628702)

Even if it is just a matter of clarifying the paper, it's still peer review in action. When OPERA responds, Contaldi will have the opportunity to review their clarifications. Maybe he'll respond again and point out that OPERA is still in the wrong. Or maybe he'll be satisfied and move on. This is how science is done. How is that not news?

Re:The OPERA team is NOT reviewing the new analysi (0)

Anonymous Coward | more than 3 years ago | (#37628796)

It's everyday science in the works. He presented an alternative explanation that's just plain wrong (he's applying a correction that had already been applied). Will we report on every single paper published on arXiv? Most of them are more relevant than Contaldi's, now that OPERA reassured the effect had been already taken into account. And that happened before the sumbission.

Re:The OPERA team is NOT reviewing the new analysi (2)

Surt (22457) | more than 3 years ago | (#37629028)

It's not news for one of two reasons, because one of two things is true:

Contaldi has poor reading skills. 'Peer review' is of low value from people who can't understand straightforward explanations that were understood by others.

or:

Science is proceeding as normal, and the outcome is still unknown .

Wake me when science reaches a conclusion, every minor typography fix on this paper is not newsworthy.

Re:The OPERA team is NOT reviewing the new analysi (2)

ColdWetDog (752185) | more than 3 years ago | (#37628720)

Oh, it's news all right. Just not end-of-the-world-as-we-know-it news. As pointed out in TFA, it's awfully hard to critique the experiment unless you're there seeing exactly what has been done. While I don't find it surprising that a few printed (or electronic) pages cannot describe hundreds of tons of equipment and countless hours of work it does speak to the complexity of modern science.

You wonder how much that is published isn't repeatable or understandable. Dropping rocks off off buildings and counting seconds with a stopwatch just doesn't cut it anymore. I read somewhere (can't quickly find it) that one of the drug companies (Bayer, IIRC) felt that over half of the experiments from the literature that they tried to repeat to consider the possibility of pharmaceutical development from the discovery, failed outright or gave much different results than published.

It's frustrating I suppose. We all know most research is wrong / useless - the hard part is teasing out which is or isn't.

Re:The OPERA team is NOT reviewing the new analysi (0)

Anonymous Coward | more than 3 years ago | (#37629122)

It's not misunderstanding if there was no explaination in the original paper. Everyone I spoke to pinned the result as clock synchronisation error; this if they'd read the paper or not (well apart from one twat who started talking about "parallel universes, quantum physics and shit!").

CERN themselves believe there's an error contributing to these results and GPS is so complex when used at this precision that a time synchronisation error remains the most likely explaination.

Seriously? (2)

hchaos (683337) | more than 3 years ago | (#37628418)

NO ONE considered the time distortion of gravity? I mean, sure, it's the first time that the time distortion due to gravity has ever been significant in any practical application, but it's still a fundamen... wait, it's not the first time? You're saying that there's an 18-year-old system that relies on this principle to work properly? How many people use this obscure system? Every single person in the civilized world? You'd think that at least one of these researchers would have heard about it, then.

Re:Seriously? (3, Funny)

Bucky24 (1943328) | more than 3 years ago | (#37628490)

I hate to say this, because I know it's probably painfully obvious to most people, but I have no idea what you're talking about.

Re:Seriously? (0)

Anonymous Coward | more than 3 years ago | (#37628538)

Gps

Re:Seriously? (5, Informative)

LateArthurDent (1403947) | more than 3 years ago | (#37628634)

I hate to say this, because I know it's probably painfully obvious to most people, but I have no idea what you're talking about.

He's talking about GPS. In order for the triangulation to work correctly, relativity must be taken into account [ohio-state.edu] .

That said, another poster pointed out [slashdot.org] that the researchers apparently did account for the effects of gravity when synchronizing their clocks. The paper just wasn't sufficiently clear on that point, and they're rewriting that section.

Re:Seriously? (1)

WCguru42 (1268530) | more than 3 years ago | (#37628648)

Global Positioning System (GPS)

Re:Seriously? (1)

Eponymous Hero (2090636) | more than 3 years ago | (#37628736)

idk either but i'm guessing the clocks on the gps satellites, re: how they run faster than time on the surface of earth and adjust the times they send back to us. am i close?

Re:Seriously? (1)

ColdWetDog (752185) | more than 3 years ago | (#37628804)

I think he's trying to get at the fact that time distortion of gravity is well known and that GPS (the 18 year old system) wouldn't work or would not work well if this wasn't taken into effect.

I am not sure that his rant is correct though, it's a small (nanosecond according TFA) difference. GPS has known uncertainties and this may very well be much smaller than known / common causes of error. It's not like the US military planned on having physicists using the GPS system for off the wall research. They were interested in blowing things up. Horse shoes and hand grenade sort of thing.

Re:Seriously? (1)

gblackwo (1087063) | more than 3 years ago | (#37629450)

According to the link, for GPS, the relativistic difference is about 38,000 ns per day, or approximately .44 ns per second.

Re:Seriously? (1)

elsurexiste (1758620) | more than 3 years ago | (#37629014)

I hate to say this, because I know it's probably painfully obvious to most people, but I have no idea what you're talking about.

Don't let that get in the way of giving your opinion! ;)

Re:Seriously? (1)

matrim99 (123693) | more than 3 years ago | (#37629078)

"What is GPS?", Alex.

Re:Seriously? (1)

whoisisis (1225718) | more than 3 years ago | (#37629334)

If you're talking about GPS, actually they do take general relativity into account.
Special relativity is only a small correction (roughly 0.1-1 km/day). Neglecting general relativity
in GPS introduces errors in the order of more than 11 km/day.

Re:Seriously? (4, Insightful)

Surt (22457) | more than 3 years ago | (#37629058)

They did consider it, the critic had a brain fail and misunderstood their paper. The researchers are doing him a kindness and 'clarifying' it for him, even though everyone else got that they had, in fact, accounted for this.

Disappointing, but expected. (1)

Attila Dimedici (1036002) | more than 3 years ago | (#37628452)

This news is disappointing, but expected. I don't mean that I expected someone to give this particular explanation, just that I expected someone to provide an explanation that did not require the neutrinos to travel faster than the speed of light.

WRONG! (4, Informative)

arkham6 (24514) | more than 3 years ago | (#37628456)

The researchers made no such claim! In fact they explicitly said they disbelieved they saw faster than light particles, and that they thought their data was faulty somewhere. But what they DID do is ask for other scientists to check their data and find their data, and if possible recreate the experiment to help track down where the error was.

THIS IS CORRECT SCIENTIFIC PROCEDURE!

Re:WRONG! (1, Interesting)

0123456 (636235) | more than 3 years ago | (#37628488)

THIS IS CORRECT SCIENTIFIC PROCEDURE!

Aside from the part where it gets plastered all over the media rather than a quiet discussion with their peers.

Re:WRONG! (4, Interesting)

ceoyoyo (59147) | more than 3 years ago | (#37628684)

That's what you get with open access science. The alternatives are simple: make the public smarter or treat them like dumb animals and don't tell them anything. I prefer the former, even if it is more difficult.

Re:WRONG! (1)

Anonymous Coward | more than 3 years ago | (#37629518)

I dunno, I'd kind of like to try out the "treat them like dumb animals" idea before dismissing it out of hand. After all, we should test hypotheses, right?

Break out the cattle prods and branding irons!

Re:WRONG! (1)

Eponymous Hero (2090636) | more than 3 years ago | (#37628750)

hehe touché

Re:WRONG! (0)

Anonymous Coward | more than 3 years ago | (#37628752)

It's the medias fault for bringing emphasis to the wrong thing.

It isn't the scientists fault for having an open discussion about THEIR OWN questionable results.

See? (0)

Anonymous Coward | more than 3 years ago | (#37628494)

My time travel method works!

explanation (1)

Dark Lord of Ohio (2459854) | more than 3 years ago | (#37628530)

Explanation to this phenomena is simple. Neutrinos travelled through tiny wormhole and that caused them to arrive faster. I won Nobel Prize!

Re:explanation (0)

Anonymous Coward | more than 3 years ago | (#37628786)

Yeah, but you'll die before the announcement. Heard that on Cable News Neutrinos!

Um, maybe it's the laws that are flawed. (0)

jbarr (2233) | more than 3 years ago | (#37628540)

I'm certainly not disputing the legitimacy of science, but in this current age of misinformation, people need to realize that science is a discipline in constant flux. Nature and the Universe tend to stay constant, following their own laws--it's Man's perceptions and understanding that are continually changing. As we learn more and more, we tune our theories, hypotheses, and laws to better understand nature's hidden mysteries.

That the observation of a sub-atomic particle appears to confound or violate established scientific law really only means that it science has yet another mystery of nature that it does not yet fully understand. Maybe the methodology is flawed. Maybe the law is flawed. But that it happens at all should certainly not surprise any scientist--it should motivate to gain a better understanding.

Re:Um, maybe it's the laws that are flawed. (0)

Anonymous Coward | more than 3 years ago | (#37628664)

I'm certainly not disputing the legitimacy of science, but in this current age of misinformation, people need to realize that science is a discipline in constant flux. Nature and the Universe tend to stay constant, following their own laws--it's Man's perceptions and understanding that are continually changing. As we learn more and more, we tune our theories, hypotheses, and laws to better understand nature's hidden mysteries.

That the observation of a sub-atomic particle appears to confound or violate established scientific law really only means that it science has yet another mystery of nature that it does not yet fully understand. Maybe the methodology is flawed. Maybe the law is flawed. But that it happens at all should certainly not surprise any scientist--it should motivate to gain a better understanding.

You must be a witch!

Re:Um, maybe it's the laws that are flawed. (0)

Anonymous Coward | more than 3 years ago | (#37629398)

Does he weight the same as a duck?

Re:Um, maybe it's the laws that are flawed. (0)

DCFusor (1763438) | more than 3 years ago | (#37628678)

Yup, and it might be obvious - a real face-palm in hindsight. We know of no other stable particles that can oscillate in flavor as neutrinos appear to do. Could it be that the mass-energy of a neutrino is not a simple number, but a complex one? Complex numbers show up all over in any math that handles anything periodic (FFT anyone?). Could it simply be that the wavefunction is large during the purported oscillation, and the new flavor pops out on the leading edge each time? There are a lot of holes not so much in the theory, but in people's gut understanding of even the current theory. Quantum stuff is pretty hard to get a gut feel for...

Re:Um, maybe it's the laws that are flawed. (0)

Anonymous Coward | more than 3 years ago | (#37629200)

What if neutrinos have negative mass?

Re:Um, maybe it's the laws that are flawed. (2)

DavidTC (10147) | more than 3 years ago | (#37629342)

Perhaps they have a mass that varies based on electrical charge! We could call it 'the mass effect'.

Perhaps all this is just a ARG for Mass Effect 3.

Re:Um, maybe it's the laws that are flawed. (1)

maxwell demon (590494) | more than 3 years ago | (#37629032)

I'm certainly not disputing the legitimacy of science, but in this current age of misinformation, people need to realize that science is a discipline in constant flux. Nature and the Universe tend to stay constant, following their own laws--it's Man's perceptions and understanding that are continually changing. As we learn more and more, we tune our theories, hypotheses, and laws to better understand nature's hidden mysteries.

That the observation of a sub-atomic particle appears to confound or violate established scientific law really only means that it science has yet another mystery of nature that it does not yet fully understand. Maybe the methodology is flawed. Maybe the law is flawed. But that it happens at all should certainly not surprise any scientist--it should motivate to gain a better understanding.

Sure, and that paper obviously tries to get a better understanding by adding a theoretically known effect to the calculation which they think the experimentalists have neglected in their analysis, and found that it indeed seems to give subluminal speed.

Note that there is another paper [arxiv.org] today on archive which also tries to explain the result in current theory, but using relativistic quantum theory instead of general relativity. I don't know whether one, the other, both or none are correct. But people will check this, and if at least one of the papers is right, then no new theory is needed. You may wish for a new theory to be needed, and for the superluminal speed to be real, but science is not about wishes, science is about facts.

"Speed" (3, Interesting)

Belial6 (794905) | more than 3 years ago | (#37628608)

Are they using some other measurement of "speed" that isn't distance / time? It seems that slowing time down and going the same "speed" has the same net effect as going faster than the speed of light.

Re:"Speed" (2)

guspasho (941623) | more than 3 years ago | (#37628834)

All of relativity is premised on the (very consistently verified) notion that speed isn't just distance/time as Newtonian mechanics would understand it, and that you must also take in to account the effects of gravity on spacetime.

Re:"Speed" (2)

frith01 (1118539) | more than 3 years ago | (#37628872)

The article states that because they moved the atomic clock used for measuring time, their time synchronization would be different for the clock while it was in italy, then when the clock was in switzerland. The difference in time synchronization is what they measured, not the speed of light.

Of course, they knew about this effect, & tried to off-set it by using GPS signals from the same satellite to correct. TFA says that GPS signal has error in time sync about 100ns, which is in scale with their measurement error.

Re:"Speed" (1)

maxwell demon (590494) | more than 3 years ago | (#37629324)

According to the abstract they say the problem is with the synchronization of clocks. If your clocks are not properly synchronized, the time you get by subtracting time points from different clocks doesn't give proper elapsed time.

As a simple example how wrong synchronization can affect apparent speeds, think about flights between different time zones. If you naively calculate flight times as time of arrival minus time of departure, you'll find that flights to the east take significantly longer than flights to the west, and in extreme cases flights to the west can even arrive before they started.

Now the synchronization in this experiment is more complex because they are dealing with noninertial frames, and at the precision needed there, that matters (at least according to the authors, but it seems reasonable, given the size of the effect).

Should already be considered (2)

Skylax (1129403) | more than 3 years ago | (#37628672)

In their original paper on arxiv they reported on using the ETRF2000 reference frame (IERS [iers.org] ) to determine the distance between the neutrino source at CERN and the detector at Gran Sasso. This reference frame already includes effects from general relativity.

If it turns out that time dilation due to gravity is the reason, then the error must be in the ETRF2000 or it was applied incorrectly in this case (Neutrinos moving from A to B). Considering that hundreds of people work on this project it seems unlikely to me that such an error slipped through. They even took into account the very small distance change induced by the L'Aquila earthquake.

Time travel proof (0)

Anonymous Coward | more than 3 years ago | (#37628716)

I can run faster then Forrest Gump on Bawls. It allows me to travel back in time.

Don't believe me? Fine, I'll go ahead and show you guys this one time....

traveling faster than light does NOT contradict SR (1)

gyepi (891047) | more than 3 years ago | (#37628740)

Contrary to what many news-sites keep repeating, it is well known that traveling faster than speed of light does not contradict special relativity. It is well known that tachyons are consistent with SR. SR only entails that a particle is either always slower than the speed of light, or is always faster than the speed of light, but can't cross that boundary from either side. The real issue is that these particles are neutrinos which are supposed to be able to travel with less than speed of light as well.

Re:traveling faster than light does NOT contradict (1)

Toonol (1057698) | more than 3 years ago | (#37629308)

Physics allows for a clown to be in my basement, but that doesn't mean there IS a clown in my basement. Because some interpretations of general relativity allow for the possibility of faster-than-light particles does not, any any sense, mean that they exist. Right now, that is purely speculation with no evidence.

(Well, no evidence until OPERA.)

Re:traveling faster than light does NOT contradict (1)

whoisisis (1225718) | more than 3 years ago | (#37629458)

The problem here is that tachyons, if they exist, move faster with lower energy, and approach the speed of light at high energies.

IIRC the neutrinos from the experiment were at much higher energies than those observed from a supernova explosion
in the 80's i think, where the photons and neutrinos arrived about simultaneous.

The vacuum in the universe isn't actually a perfect vacuum, and thus it has a small refractive index,
meaning the the speed of light in the universe is a bit slower than in perfect vacuum, so those
neutrinos can travlel faster than light and could be used to tell us in advance when a supernova explosion occured,
so we can point our telescopes in that direction.

Interaction Difference (0)

McLoud (92118) | more than 3 years ago | (#37628744)

I wonder if light is being affected by space-time some way and neutrinos aren't. Then they measure the true maximum allowed speed better than light does. Taking that into account, how the theories will look like using c @ neutrino's speed ?

well we have a new project for Dr Hawking (0)

Anonymous Coward | more than 3 years ago | (#37628762)

extra-Special Relativity. breaking it's own rules for yet another reason.

You can't go c but you can go faster (1)

ohmiccurmudgeon (1443977) | more than 3 years ago | (#37629068)

I'm a mathematician, not a physicist. In special relativity the Lorentz transformation has a singularity at the speed of light. Its perfectly defined below and faster than the speed of light. Richard Feynman suggested that unless the math prohibits it, it will be found in nature. Of course, if we see a particle hitting another before it was emitted, we'd likely interpret it as the target "pulled" the particle from the emitter. This explains the alternate view of physics -- all matter emits dark, and light bulbs and stars suck the dark in. Mathematically it makes just as much sense as emitting massless photons. Who's going to buy the idea of a massless particle that goes the speed of light? Its crazy talk.

This is just a reminder that like economics, scientific method is really a confidence game. Its all a matter of whether you believe the rules stated so far are consistent.

Re:You can't go c but you can go faster (0)

Anonymous Coward | more than 3 years ago | (#37629486)

Its all a matter of whether the models explain what is happening. Newtons laws of gravity aren't necessarily wrong, they just don't work in certain circumstances. We still travel to the moon using newtons equations. The models help us do stuff.

Re:You can't go c but you can go faster (1)

whoisisis (1225718) | more than 3 years ago | (#37629532)

Yes, faster than c speeds are ok but require your mass to be purely imaginary.
What does that mean?

relativity. (1)

Oswald McWeany (2428506) | more than 3 years ago | (#37629112)

They could never duplicate this experiment in West Virginia because relativity is hard to define there.

I believe GR & SR (1)

FlyingGuy (989135) | more than 3 years ago | (#37629256)

I personally chalk it up to the measurement between the emitter and the detector.

Yes I know they say they are very confident within a margin of error and that amount they are observing is within that margin of error so it must be right??

Personally I aint gonna start changing C based upon their confidence that their variation is within the margin of error that they say is within the margin of error of the distance between the gun and the target since everything else in GR & SR has been demonstrated correct thus far.

Time dilation of the earth? (1)

AnotherBlackHat (265897) | more than 3 years ago | (#37629268)

failed to take into account differences in earth's gravitational field

Even if they didn't account for it, so what?
The Schwarzschild solution for Time dilation has a C squared in the divisor.
Unless I'm doing the math wrong, It wouldn't even amount to 1 nanosecond, much less 60.

On use of duct tape to fix cracked pots (1)

WaffleMonster (969671) | more than 3 years ago | (#37629456)

"let us assume that the TTD was stationary at the LNGS site for 4 days while the appara-tus for clock comparison was set up. Using the value of V/c2 quoted above this would result in a total shift of t 30 ns."

Let us assume a scenario which fits our desired outcome has actually occured without any supporting evidence since our own figures fall far short of a cogent explanation for the discrepancy.

Let us further overlook the fact PTB was mearly used to independantly *VERIFY* the nanosecond level clock synchronization calibrated by METAS of the time links between the two stations.

From the OPERA paper:
"The difference between the time base of the CERN and OPERA PolaRx2e receivers was
measured to be (2.3 ± 0.9) ns"

Ooops...

"More importantly, we have only considered the path taken by the TTD along a surface trajectory. The path taken by the neutrinos is some 3 kms below the surface at its midpoint along the trajectory connecting CERN and LNGS. At this level of accuracy the surface time mea-sured by all clocks involved will differ from the proper time along the true trajectory and this further compli-cates the interpretation of the OPERA results."

The difference between totally switching off the earths effect on spacetime as the neutrino beam moves 730km results in being able to cover .5mm more distance over the same time. The effect is not worth thinking about yet they deem it necessary to include it anyway. Their own figures come up short.

Nitpicking the title of the post... (2)

ocean_soul (1019086) | more than 3 years ago | (#37629522)

Actually, the theory of special relativity has no problem with particles going faster than light. The problem lies with accelerating particles from slower than light in vacuum to faster than light in vacuum. Or, for that matter, with slowing down from faster to slower than c.

One possible test (2)

jonbryce (703250) | more than 3 years ago | (#37629528)

Would it be possible to have neutrino generators and detectors at both sites and test the speed in both directions? That would probably mean testing the speed between CERN and Fermilab. That way, if there was an error in clock synchronisation, it would show up because the neutrinos would take longer in one direction than the other.

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