[SCIENCE]Neutrino experiment sees them apparently moving faster than light

[Antithesis]

Neutrino experiment sees them apparently moving faster than light
http://static.arstechnica.net/assets...auto-25733.jpg

Tomorrow, researchers from CERN will be releasing experiment results that suggest neutrinos, the lightest particles we're aware of, may be moving slightly faster than the speed of light. Although the results have not yet been made public (a webcast will accompany the release of the paper), rumors of the finding have spread far and wide, leading to coverage by the BBC and the AP. Still, because the findings would seem to violate relativity, the authors are being very cautious about their results, and many in the physics community are expressing skepticism.

Neutrinos have generally made the news because they engage in what are called flavor oscillations, in which (to give one example) an experiment that creates only muon neutrinos will see some of them behave as electron neutrinos when they hit a detector. These oscillations confirmed that neutrinos must have mass, although they are orders of magnitude lighter than any of the other fundamental particles. That extremely low mass means that it doesn't take much energy to get them moving very quickly, which allows physicists who work on neutrino detectors to simply treat them as if they are moving at the speed of light when calculating their expected behavior.

As far as we could tell, this was a pretty good approximaiton. Neutrinos are produced in copious quantities in supernovae, and despite the enormous distances, they arrive at about the same time as the photons generated in the explosion. (The neutrinos actually get here a bit more quickly because they so rarely interact with matter, meaning they can escape the core of the star without incident. The photons, in contrast, get held up by interacting with the outer layers of the star, and typically appear a short time afterwards.)

Fermilab's MINOS experiment has also measured the speed of neutrinos that are produced on-site near Chicago, then sent to a detector in a mine in Minnesota. "MINOS also measured a faster-than-light value of the neutrino speed," MINOS co-spokesperson Jenny Thomas told Ars, "but the errors were so big we dismissed it."

Thomas said there are three potential sources of error. You have to measure both the distance travelled and time of flight very accurately, and then you have to account for what she called the "time structure of the accelerator," which is related to how you handle the protons that are used to produce neutrinos in these experiments. Errors in any one of these factors can introduce errors into the results.

CERN has a similar, higher-energy version of the Fermi experiment called OPERA, which sends neutrinos from a source in Switzerland to a detector at Gran Sasso in Italy. After accounting for all the sources of error, the people running the OPERA experiment expect that their measurements may be off by as much as 10 nanoseconds. The neutrinos got there 60 nanoseconds ahead of when we'd expect them to arrive if they were moving at the speed of light.

There's definitely the chance that the error estimates are off, and several phsicists are expecting that will be the case. That's in part because this would seem to violate relativity, which is a very-well-supported theory, and in part because we don't have a good theoretical basis for expecting neutrinos to do anything like this. One physics blogger who commented on the results wrote, "If you are wondering about theories that allow tachyonic [faster than light] neutrinos the least wacky one I can find is that neutrinos can take 'shortcuts off the brane through large extra dimensions.'"

The final reason to be skeptical is the fact that this effect hasn't shown up in previous measurements. Thomas noted that it might be a matter of energy. Neutrinos from supernovae are relatively low energy; MINOS' were much higher, at which point a weak effect turned up. The OPERA studies are at higher energy still. So the results don't appear to be exactly comparable.

For now, however, those results are being kept under wraps until the webcast tomorrow. Once they're released, you can bet the physics community will be overloading the server, looking for the chance to poke holes in the results.

Source: Ars Technica
http://arstechnica.com/science/news/...than-light.ars

Secondary Article: http://gizmodo.com/5843006/faster-th...ativity-theory

[idklol]

I don't know all that much about physics but i like to keep what i would consider a keen interest. If this turns out to be right and the neutrinos? are FTL then what are the implications of it? Shit gonna hit the fan? Really interested to see this develops.

edit: also http://www.bbc.co.uk/news/science-environment-15017484

[quannum]

google cache of the blog thats been taken down

http://webcache.googleusercontent.co...2l2-1.2.2l11l0

[Blarg]

Seems like it says that in a vacuum light photons and neutrinos would be same speed but because neutrinos are so small they avoid interacting with matter so in the 'real world' they are 'faster'.

[Demosthenes11]

Seems like it says that in a vacuum light photons and neutrinos would be same speed but because neutrinos are so small they avoid interacting with matter so in the 'real world' they are 'faster'.

That's kinda cheating then

[Qalbert]

so we just need to build a spaceship out of neutrinos and then we're good to go

[Valkrish]

Seems like it says that in a vacuum light photons and neutrinos would be same speed but because neutrinos are so small they avoid interacting with matter so in the 'real world' they are 'faster'.

maphacking sons of bitches!

[Blarg]

so we just need to build a spaceship out of neutrinos and then we're good to go

unless the astronauts also have suits made out of neutrinos they won't be able to board the ship in time before it speeds off without them


use ur brain next time

[Kaylia]

I don't know all that much about physics but i like to keep what i would consider a keen interest. If this turns out to be right and the neutrinos? are FTL then what are the implications of it? Shit gonna hit the fan? Really interested to see this develops.

edit: also http://www.bbc.co.uk/news/science-environment-15017484

It would implies that both relativity and quantum mechanics need major overhaul, but we knew this already, we just didn't expect the issue to be that big.

If it turn out to be truth, it will be a very important piece of the puzzle that physicist are trying to solve for the last 50 years. We are from solving it, but the more pieces we have, the more likely it is that someone figure out a starting point.


What are the implication of this? Probably very little, unless you can actually communicate faster than light, but something tell me there will be a catch somewhere.

[Kaylia]

Seems like it says that in a vacuum light photons and neutrinos would be same speed but because neutrinos are so small they avoid interacting with matter so in the 'real world' they are 'faster'.

This articles isn't talking about the speed of light in matter, which is still technically 300 000 km/s (it will seem slower because light is busy jumping between atoms, and the distance traveled end up being longer than a direct line).

[Zalius]

sweet. supernovae is the plural of supernova.

[miokomioko]

sweet. supernovae is the plural of supernova.

That's what I came away from this with.

[Maguspk]

sweet. supernovae is the plural of supernova.

Holy shit, Zalius.

[Zalius]

browsing a science thread near you
sup bb

[Correction]

Might as well get this out of the way

[Shuvo]

Typically when these types of articles come out, the comments on places like slashdot rips it to shreds. But in this case nobody can find anything o_o Might actually be true. Exciting!!

[Doombard]

u mad einstein?

[Doombard]

u mad einstein?

[quannum]

google cache of the blog thats been taken down

http://webcache.googleusercontent.co...2l2-1.2.2l11l0

a follow-up

So, as I had announced a bit prematurely three days ago, the Opera experiment is about to release the results of a measurement that is bound to stir endless discussions. If you read the piece before I took it down (to comply with a request coming from high up above), or even Lubos Motl's blog, you know what this is about; but by now it is not a mystery in any case, since many newspapers are now discussing the news, although they often misrepresent things, as usual (heck, the newspaper "La Stampa" has a short piece in its online version tonight, where they manage to claim that Einstein was wrong and that the theory of relativity is being questioned; plus, the picture they show is... the CMS experiment!)

I will re-post my piece, slightly updated, tomorrow. But I am sure you can find by now lots of information on the matter in blogs and sites around. The heart of the matter is that energetic muon neutrinos shot from CERN 730 km away, to the underground lab of Gran Sasso in central Italy, appear to be traveling faster than light.

So let us connect tomorrow at 4PM Geneva time to the CERN seminar. You can do so at this link. And then come back here for a discussion!

[Valkrish]

I looked all over cern and documentations once :3 it was full of C and old programming language how-to's