The neutrinos from the future...

[akhare]

http://www.reuters.com/article/2011/09/22/science-light-idUSL5E7KM4CW20110922

[whereagles]

interesting... if it gets confirmed, it's major news

[semeai]

Crazy. Of course, extraordinary claims require extraordinary evidence, so none of us should really believe this yet. It would be very exciting, though.

 

According to their measurements, it sounds like the neutrinos were going roughly 299800 km/s compared to roughly 299792 km/s for light.

[JLOGIC]

Dammit I came here to post this lol

[JLOGIC]

I can't wait to travel back in time, it's only a matter of time... or is it?

[mike777]

faster than light

 

 

effect before cause

 

2 photons occupy the same space and time

 

the smaller you go the more space there is.

 

 

 

aint the universe full of wonder.

[hotShot]

This is a suitable response.

[JLOGIC]

I knew John Titor was not a hoax!!!

[hrothgar]

Particle man, particle man

Doing the things a particle can...

[y66]

Guess what?

[Winstonm]

The neutrino did not speed up; the observer slowed down.

[gwnn]

Lorentz transforms are just too cool to be false.

[BunnyGo]

Lorentz transforms are just too cool to be false.

 

But they're just the 4-dimensional projections of what are really going on. Maybe neutrinos jump through another dimension.

 

(I'll still take the bet that this is a measurement failure)

[barmar]

When I first heard the story, my first thought was that there might be some quantum tunneling going on. But if this is a possibility, I can't imagine the scientists wouldn't have thought of it, it's way too obvious. Quantum dynamics causes a number of behaviors that appear to violate relativity, such as black holes giving off Hawking radiation (due to spontaneous creation of a particle and its antiparticle just outside the event horizon -- one of them falls in, the other zips away).

[BunnyGo]

When I first heard the story, my first thought was that there might be some quantum tunneling going on. But if this is a possibility, I can't imagine the scientists wouldn't have thought of it, it's way too obvious. Quantum dynamics causes a number of behaviors that appear to violate relativity, such as black holes giving off Hawking radiation (due to spontaneous creation of a particle and its antiparticle just outside the event horizon -- one of them falls in, the other zips away).

 

Unless you're using the same term to refer to two different things, quantum tunneling isn't a way of traveling faster, it's a way of escaping energy wells (i.e. if a particle is "trapped" in a place requiring more enegy to escape than the particle has it can "tunnel" it's way under the energy hump).

[helene_t]

Unless you're using the same term to refer to two different things, quantum tunneling isn't a way of traveling faster, it's a way of escaping energy wells (i.e. if a particle is "trapped" in a place requiring more enegy to escape than the particle has it can "tunnel" it's way under the energy hump).

I think barmar had wormholes rather than tunelling in mind? At least that was my first thought. But it isn't plausible.

[blackshoe]

Whatever they're doing, if they aren't carrying information (for example "Ron Paul Wins!" :P ) they're useless.

[Gerben42]

Well if it's quantum tunneling, the average particle would still arrive just in time. Even if you would for some reason only see the "too early" group, you would see much fewer particles than the total number of particles that were sent.

[babalu1997]

damn you all smart!

[barmar]

I'm not an expert on quantum theory, but I thought that tunneling could essentially allow a particle to disappear here and reappear instantaneously somewhere else. We call it tunneling because the interesting case is when somewhere else is on the other side of some barrier, but it could just as easily be just some distance away. Quantum processes allow things like this because it's about probabilities and statistics -- individual particles can do almost anything, but if you have lots of them they average out to the macroscopic expectations.

 

But it sounds like the scientists were measuring the speed of a stream of particles. Tunneling, if it works like I thought, would perhaps allow a few individual particles to jump ahead of the pack, but the stream as a whole should obey relativity. Unless they can tag individual neutrinos and detect their arrivals, I don't think they'd be able to detect this.

 

I don't even know how they measure the neutrino speed in the first place. I guess they transmit a very short burst of neutrinos, and then detect when they arrive. But neutrinos are extremely hard to detect, so the burst must have lots of particles in it, and they'll only detect a small number of them arriving. Maybe some of the tests detect the particles that tunnel ahead. But I'd expect them to repeat the test many times and average the results, to filter out quantum effets.

[gwnn]

btw just did a very simple calculation and 60ns is equivalent to a distance of 18 metres at the speed of light, and 1/40 000 of the total time.

 

The paper is here: http://static.arxiv.org/pdf/1109.4897.pdf

 

They claim an error of about +/- 10 ns, or so, if I'm reading it correctly.

[barmar]

btw just did a very simple calculation and 60ns is equivalent to a distance of 18 metres at the speed of light, and 1/40 000 of the total time.

Ouch, there goes my tunneling theory. I have no idea how to do the calculations, but my guess is that you could probably count the number of particles on earth that would tunnel that far on your fingers.

[PassedOut]

Faster-than-Light Neutrino Puzzle Claimed Solved by Special Relativity

 

So what is the satellites' motion with respect to the OPERA experiment? These probes orbit from West to East in a plane inclined at 55 degrees to the equator. Significantly, that's roughly in line with the neutrino flight path. Their relative motion is then easy to calculate.

 

So from the point of view of a clock on board a GPS satellite, the positions of the neutrino source and detector are changing. "From the perspective of the clock, the detector is moving towards the source and consequently the distance travelled by the particles as observed from the clock is shorter," says van Elburg.

 

By this he means shorter than the distance measured in the reference frame on the ground.

 

The OPERA team overlooks this because it thinks of the clocks as on the ground not in orbit.

 

How big is this effect? Van Elburg calculates that it should cause the neutrinos to arrive 32 nanoseconds early. But this must be doubled because the same error occurs at each end of the experiment. So the total correction is 64 nanoseconds, almost exactly what the OPERA team observes.

[Winstonm]

Faster-than-Light Neutrino Puzzle Claimed Solved by Special Relativity

 

Well, that certainly refutes the lyrics, "Ti-i-i-i-ime is on my side, yes it is."

[barmar]

The last paragraph is the best:

If it stands up, this episode will be laden with irony. Far from breaking Einstein's theory of relatively, the faster-than-light measurement will turn out to be another confirmation of it.

What got me was the earlier comment: "the tricky part is keeping the clocks at either end exactly synchronised." Doesn't Special Relativity say that there's no such thing as synchronized clocks?