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CERN press release regarding neutrino experiment

press.web.cern.ch

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Re: CERN press release regarding neutrino experiment

#31

Post by lutorm »

orblivion wrote: post #7
simplegeek wrote: post #6

Guys, I'm sorry I missed this recent news but I've a question that I hope some people can answer for me. So does this mean that Einstein's theory might not hold? Do we see any well-established theories break as result of this? I'm totally naive about this but curious so any answers will be appreciated.

I'm not the best to answer this, but I'll briefly say that if Einstein's theories don't hold, it will be in the same sense that Newton's theories didn't hold post-Einstein. Newton's theories still apply, for all practical purposes, to all every-day life situations, and Einstein's theories will still apply, for all practical purposes, to every fringe case seen so far ("every-day" nuclear physics, etc) until this exper…

We sort of already know that "Einstein is wrong" in this strong sense, since GR is incompatible with quantum field theory. It still works just as well within its realm of applicability, though.

Re: CERN press release regarding neutrino experiment

#32

Post by Confusion »

simplegeek wrote: post #6

Guys, I'm sorry I missed this recent news but I've a question that I hope some people can answer for me. So does this mean that Einstein's theory might not hold? Do we see any well-established theories break as result of this? I'm totally naive about this but curious so any answers will be appreciated.

No matter what they discovered: Einstein's theories of relativity will hold. They will hold forever, just like Newtons theory of gravity will hold forever. It's just that its range of applicability may become smaller and smaller.

There have been numerous experiments that perfectly validate both the special and general theory of relativity. The outcomes of the same experiments will not suddenly change. The theories predict the outcomes of these experiments to within experimental accuracy. GPS wouldn't work if special relativity wasn't a sufficiently accurate description of reality.

However, it may turn out that there are also experiments that are not sufficiently described by the theories of relativity, even thought that was previously expected.

Re: CERN press release regarding neutrino experiment

#33

Post by lutorm »

mrb wrote: post #27

My SWAG: the relativist effect of time being slowed down in Earth's gravity was not taken into account. (Time is slowed down, therefore neutrinos appear to arrive 60ns "early".) They spent a lot of time triple checking the accuracy of their instruments without seemingly thinking about higher level factors such as the Theory of relativity... http://static.arxiv.org/pdf/1109.4897.pdf Of course there are 99% chances I a…

You didn't look at the webcast, did you? Someone asked this question and they said "no we took it into account in the sense that the clocks at CERN and Gran Sasso run at different speeds because they are at different elevations. However, that's only a 1e-18 effect and the signal is 1e-5.

Re: CERN press release regarding neutrino experiment

#34

Post by sprovoost »

arethuza wrote: post #3

Although it is CERN that is getting most of the attention the lab receiving the neutrinos is pretty impressive - 1400m underground: "three large experimental halls, each about 100 m long, 20 m wide and 18 m high and service tunnels, for a total volume of about 180,000 cubic metres" http://www.lngs.infn.it/home.htm

To put that in perspective: a 20 part per million difference in speed over 730 km distance is about 15 metres. So details about the detector are relevant, but they obviously know that.

Re: CERN press release regarding neutrino experiment

#35

Post by saulrh »

ajross wrote: post #17
saulrh wrote: post #2

This press release is a perfect example of how to write a press release for a high-profile, possibly groundbreaking discovery. Understated, but still properly summarizes the importance of the result, and above all doesn't make any hysterical claims. Instead, it just presents the discovery, cites the paper, gives some background, grabs quotes from the scientists to show the reasoning behind their actions, and leaves i…

All true. But to be fair, you're praising the easy stuff. This is one of those one-in-a-career, truly groundbreaking results. They don't have to sell it. They just write it up in plain language and it sells itself.

That's the thing - they resisted the urge to sell it. All of the other headlines are screaming about "time travel possible?" and "modern physics all wrong!", while this is just the plain language.

Re: CERN press release regarding neutrino experiment

#36

Post by AndreiVajnaII »

simplegeek wrote: post #6

Guys, I'm sorry I missed this recent news but I've a question that I hope some people can answer for me. So does this mean that Einstein's theory might not hold? Do we see any well-established theories break as result of this? I'm totally naive about this but curious so any answers will be appreciated.

The theory of relativity is based on the fact that the speed of light is the same for any observer, no matter if that observer is standing still or moving. From this supposition, the rest of the theory is just mathematics. So if there is something than can move faster than that speed, then the theory will still hold, as long as everybody observes the same speed, in any state of movement they are.

Re: CERN press release regarding neutrino experiment

#39

Post by mootothemax »

There are a few interesting explanations in a Guardian article[1] published today:

Heinrich Paes at Dortmund University and colleagues believe it might be possible for neutrinos to move through hidden, extra dimensions of space and effectively take shortcuts through space-time. "The extra dimension is warped in a way that particles moving through it can travel faster than particles that go through the known three dimensions of space. It's like a shortcut through this extra dimension. So it looks like particles are going faster than light, but actually they don't."

Another potential explanation for the observation was given by Alan Kostelecky at Indiana University, who has devoted his career to violations of the limiting speed of light. He proposed in 1985 that an energy field that lies unseen in the vacuum might explain the finding. The field allows neutrinos to move faster through space than photons, the particles that make up light.

"It may very well be that neutrinos travel faster than light does in that medium. It is not at all unreasonable that that would be the case."

[1]http://www.guardian.co.uk/science/2011/sep/23/physicists-spe...

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