Merged Puzzling results from CERN

[Craig B]

Would suggest reading Feyerabend's "Against Method" for just a tiny bit of insight into modern scientific hubris.

Yes, so would Benedict XVI in his anti science Parma speech in 1990. Feyerabend was nuts. See his wiki entry

Feyerabend commented on the Galileo affair as follows: "The church at the time of Galileo was much more faithful to reason than Galileo himself, and also took into consideration the ethical and social consequences of Galileo's doctrine. Its verdict against Galileo was rational and just, and revisionism can be legitimized solely for motives of political opportunism."

Political opportunism! But here is what he has to say about science in general:

Feyerabend described science as being essentially anarchistic, obsessed with its own mythology, and as making claims to truth well beyond its actual capacity. He was especially indignant about the condescending attitudes of many scientists towards alternative traditions. For example, he thought that negative opinions about astrology and the effectivity of rain dances were not justified by scientific research, and dismissed the predominantly negative attitudes of scientists towards such phenomena as elitist or racist. ... He envisioned a "free society" in which "all traditions have equal rights and equal access to the centres of power" ( Science in a Free Society. p. 9.). For example, parents should be able to determine the ideological context of their children's education, instead of having limited options because of scientific standards. According to Feyerabend, science should also be subjected to democratic control: not only should the subjects that are investigated by scientists be determined by popular election, scientific assumptions and conclusions should also be supervised by committees of lay people. He thought that citizens should use their own principles when making decisions about these matters.

These utterances are completely crazy. If anyone thinks otherwise, please say why.

 

[Wangler]

I don't know if anyone has posted this yet, but here is an interesting critique (by John Costella, a particle physicist in Melbourne) of the statistical analysis performed by the CERN-OPERA team which seems to cast considerable doubt on their FTL claims.

Costella has since retracted his initial statistical analysis critique, and has shown that the OPERA result is indeed statistically significant.

 

[Craig B]

As noted above

According to Feyerabend, science should also be subjected to democratic control: not only should the subjects that are investigated by scientists be determined by popular election, scientific assumptions and conclusions should also be supervised by committees of lay people. He thought that citizens should use their own principles when making decisions about these matters.

Should we apply these principles to the neutrino puzzle? Or do hubristic elitist scientists intend to lay down the law on this?

 

[Kuko 4000]

I have not looked through the many preceding pages, so I hope I am not repetitious.

Hi Tim, please look at this post:

http://www.internationalskeptics.com/forums/showpost.php?p=7609859&postcount=528

I'm interested in your thoughts about their video presentation and QA session.

 

[icerat]

The Guardian had a couple of physics professors do a Q&A in their comments section on Friday. Very useful in helping we non-physicists to understand the issues.

The relevant replies in the comments are from StefanSoldnerRembold and ProfMarkLancaster

 

[Molinaro]

From the paper, a more informative & authoritative source than any press release:

In this paper we report on the precision determination of the neutrino velocity, defined as the ratio of the precisely measured distance from CERN to OPERA to the time of flight of neutrinos traveling through Earth's crust. We used the high-statistics data taken by OPERA in the years 2009, 2020 and 2011. Dedicated upgrades to the timing systems for the time tagging of the CNGS beam at CERN and of the OPERA detector at LNGS resulted in the reduction of the systematic uncertainties down to the level of the statistical error. The measurement also relies on a high-accuracy geodesy campaign that allowed measuring the 730 km CNGS baseline with a precision of 20 cm.

I bet it was that data from 2020 that messed things up.

 

[Raze]

It's impossible under the known laws of physics. So, if it's true, those laws are wrong. And not wrong in a small way - faster than light propagation, even if only by a little, means that the particle is propagating back in time in someone's reference frame.

There are ways you might be able to modify physics to make this possible and not cause everything to melt down - but no one has ever come up with a theory that allows that and is also consistent with everything else we know.

In short, one of the best-tested features of nature says this is impossible.

I don't understand why. Couldn't you just redefine c to be a little faster than about 3x10^8 m/s and keep all the math?

ETA- wait, never mind. Neutrinos have mass.

 

[nathan]

I'm not sure how much CERN has to do with this. The detector is at Gran Sasso, Italy. The LHC is just used as a neutrino source.

Good point, they're trying to detract from the fact they're about to blow up the Euro! Or Berlusconi's going to jail ... or something

 

[sol invictus]

However, one should be surprised to see them travel through Earth's crust faster than the speed of light in vacuo. Whether or not this would constitute a violation of special relativity is not at all obvious.

I don't agree. If this result stands, it is a clear violation of SR.

Remember some years back, when under special laboratory conditions, laser pulses traveled through special filters, apparently faster than the speed of light in vacuo (e.g., Wang, Kuzmich & Dogariu, 2000).

It's possible for group velocities to exceed c - there's nothing even slightly exotic or surprising about that. But it is impossible (if SR is correct) for the signal velocity to exceed c. In other words, if someone does something at CERN (like smashing a proton into a graphite block), no signal of that event can reach Gran Sasso before light in vacuum would have.

While the recent result might be explained by something related to group velocities (for instance, the proton pulses are quite wide, and "when" they first hit the graphite block is hence not very well defined), if that is the explanation it does not mean that neutrinos propagate faster than c.

It has also been known for a long time that quantum tunneling can proceed faster than implied by light speed over the same distance (e.g., Hartman, 1962).

Again, signal velocities cannot exceed c under any circumstances, including in relativistic quantum theories in scenaria involving tunneling.

A final interpretation of the implications of this result must rely on a detailed understanding of the quantum mechanical interaction between the neutrinos and Earth's crust, especially the possible effect of tunneling.

I don't see how tunneling or the earth's crust have anything at all to do with this.

 

[sol invictus]

I don't understand why. Couldn't you just redefine c to be a little faster than about 3x10^8 m/s and keep all the math?

ETA- wait, never mind. Neutrinos have mass.

It's not the neutrino mass that's relevant, it's the fact that the speed of light in vacuum (which is the definition of c) has been measured to far better accuracy than a part in 10^-5.

So no - we can't just redefine c, because we already know what it is.

 

[BenBurch]

Over astronomical distances, an effect like this would be pronounced. If I have computed this right in my head, over a light year we would be looking at around ten hours difference between EMR and a neutrino pulse originating at the same time. Which would mean that detecting a neutrino pulse, and having its direction determined, might give you weeks of notice about where to train your instruments to record the event.

And I think we would have noticed this, but I'm not certain.

 

[Raze]

It's not the neutrino mass that's relevant, it's the fact that the speed of light in vacuum (which is the definition of c) has been measured to far better accuracy than a part in 10^-5.

So no - we can't just redefine c, because we already know what it is.

What I mean is, what if the maximum speed wasn't actually c, but a little faster. Wouldn't the Lorentz transformation equations look exactly the same? I mean, if you start with a speed that is constant in all inertial frames, won't you always derive the Lorentz transformation equations, regardless of what the particular magnitude of that speed is?

 

[sol invictus]

Over astronomical distances, an effect like this would be pronounced. If I have computed this right in my head, over a light year we would be looking at around ten hours difference between EMR and a neutrino pulse originating at the same time. Which would mean that detecting a neutrino pulse, and having its direction determined, might give you weeks of notice about where to train your instruments to record the event.

And I think we would have noticed this, but I'm not certain.

It was already tested with supernova 1987A. Neutrinos from that event moved at speed c to within experimental uncertainty. Had they moved at the speed the Opera results indicate, they would have arrived months or years earlier.

What I mean is, what if the maximum speed wasn't actually c, but a little faster. Wouldn't the Lorentz transformation equations look exactly the same? I mean, if you start with a speed that is constant in all inertial frames, won't you always derive the Lorentz transformation equations, regardless of what the particular magnitude of that speed is?

No - you'll derive a different set of transformations that are identical to the Lorentz transforms except that the speed involved is different. For instance, you can go through Einstein's 1905 paper and replace "speed of light in vacuum" everywhere with "speed of sound in air at standard temperature and pressure". You'll define a set of coordinate and transformations that look like Lorentz transforms, but with c replaced by 330 m/s or so. In those coordinates, the speed of sound is the same in all "inertial" reference frames (including those that are moving with respect to the air).

However, the physical content of relativity is the assertion that the laws of physics are invariant under Lorentz transformations. That actually guarantees that light must travel at speed c (the speed in the transform), because otherwise Maxwell's equations would not be invariant (they are not invariant under sound "Lorentz" transforms, for instance).

So in short, the speed that appears in Lorentz transforms is a physical quantity that can be measured, has been measured, and the uncertainty in it is far below the level the OPERA collaboration found.

 

[sol invictus]

Here's a writeup (with comments after) by an accomplished particle theorist:

http://profmattstrassler.com/2011/09/23/some-comments-on-the-faster-than-light-neutrinos/

I'd say he's slightly underselling the significance of this if it's confirmed - I don't think any of the Lorentz-violating theories he mentions have much chance of working.

There are some previous posts on this topic on his blog as well.

 

[Raze]

It was already tested with supernova 1987A. Neutrinos from that event moved at speed c to within experimental uncertainty. Had they moved at the speed the Opera results indicate, they would have arrived months or years earlier.



No - you'll derive a different set of transformations that are identical to the Lorentz transforms except that the speed involved is different. For instance, you can go through Einstein's 1905 paper and replace "speed of light in vacuum" everywhere with "speed of sound in air at standard temperature and pressure". You'll define a set of coordinate and transformations that look like Lorentz transforms, but with c replaced by 330 m/s or so. In those coordinates, the speed of sound is the same in all "inertial" reference frames (including those that are moving with respect to the air).

However, the physical content of relativity is the assertion that the laws of physics are invariant under Lorentz transformations. That actually guarantees that light must travel at speed c (the speed in the transform), because otherwise Maxwell's equations would not be invariant (they are not invariant under sound "Lorentz" transforms, for instance).

So in short, the speed that appears in Lorentz transforms is a physical quantity that can be measured, has been measured, and the uncertainty in it is far below the level the OPERA collaboration found.

I hope I'm not being annoying, but what if you replace all the c's in Maxwell's equations with a new speed that is slightly faster than c? If I'm not mistaken, c comes from the defined constants of the permeability and permittivity of free space. What if those constants are altered by 20 parts in a billion (or whatever the alleged number is). Would it greatly affect any measurements?

ETA- just saw the link you posted. Investigating now.

 

[icerat]

It was already tested with supernova 1987A. Neutrinos from that event moved at speed c to within experimental uncertainty. Had they moved at the speed the Opera results indicate, they would have arrived months or years earlier.

I'm no expert, but experts I've read have said this just means the anomaly may be energy dependent, as the CERN/GRASSO neutrinos are much higher energy than those from 1987A.

 

[sol invictus]

I hope I'm not being annoying, but what if you replace all the c's in Maxwell's equations with a new speed that is slightly faster than c? If I'm not mistaken, c comes from the defined constants of the permeability and permittivity of free space. What if those constants are altered by 20 parts in a billion (or whatever the alleged number is). Would it greatly affect any measurements?

Yes - it would change the speed of light in vacuum to whatever new speed you put in. That's what I'm trying to explain to you - we've measured the speed of light in vacuum to very high accuracy. We know what it is, and it's slower than the speed OPERA measured.

I'm no expert, but experts I've read have said this just means the anomaly may be energy dependent, as the CERN/GRASSO neutrinos are much higher energy than those from 1987A.

What they probably said is that 1987A does not necessarily conflict with this, because the speed could be energy dependent (or for many other reasons I can think of off the top of my head). That's true - any combination of experimental data can be explained by a sufficiently complicated theory. Nevertheless, the simplest interpretation of OPERA is that neutrinos always travel at 1.00002c, and that is in fact ruled out by 1987A.

More importantly, the OPERA result is in direct conflict with most of what we know about physics, including much of the most precise data ever collected and the most successful theories in the history of science. That doesn't prove it's wrong, but it makes it very, very likely.

 

[Raze]

Yes - it would change the speed of light in vacuum to whatever new speed you put in. That's what I'm trying to explain to you - we've measured the speed of light in vacuum to very high accuracy. We know what it is, and it's slower than the speed OPERA measured.

[...]

So what would be the theoretical consequences if the speed we measure, the speed of light, isn't actually the universal speed limit but is instead very near to it?

 

[sol invictus]

So what would be the theoretical consequences if the speed we measure, the speed of light, isn't actually the universal speed limit but is instead very near to it?

Unknown, but huge. There is no such theory known. There are attempts, but in my opinion none of them have much chance of working (i.e., of agreeing with experiment).

 

[nvidiot]

Regarding the 1987 supernova example, was anyone looking for examples of anomalous neutrinos around the time they should have if neutrinos moved this much faster than c?

i.e. You can't find something if you don't know it's there, although I can only imagine someone has gone through their records since this report.