
CERN press release regarding neutrino experiment - AndreiVajnaII
http://press.web.cern.ch/press/PressReleases/Releases2011/PR19.11E.html
======
saulrh
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 it at that. Beautiful.

~~~
ajross
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.

~~~
cube13
Most importantly, they're not presenting the finding as fact. They're really
asking for anyone that can prove them wrong, because they don't believe it,
and are almost positive that there's something wrong with either their
methodology or measurements.

~~~
drbaltar
I wonder how the Cold Fusion fiasco was presented back in the 90's? Not that
they are at all similar, but those were certainly bold claims as well.

~~~
Luyt
There was an interesting (and entertaining) book written about the Cold Fusion
Hype,
[http://en.wikipedia.org/wiki/Bad_Science:_The_Short_Life_and...](http://en.wikipedia.org/wiki/Bad_Science:_The_Short_Life_and_Weird_Times_of_Cold_Fusion)

From Gary Taubes' (the author) website: _Bad Science: The Short Life and Weird
Times of Cold Fusion is book of science history by Gary Taubes about the early
years (1989–1991) of the cold fusion controversy. It is not a scholarly work,
but a popular retelling of the events, based on interviews with over 260
people. The book presents a timeline of the events, making the case that the
cold fusion field has many examples of poorly-performed science. The actions
of Martin Fleischmann, Stanley Pons, and Steven E. Jones, the scientists who
made the dramatic first claims of fusion, are described in rich detail. The
book then shows the worldwide reaction and later disrepute of the cold fusion
field, with Taubes placing himself in the side of "good science". Taubes says
at the end that cold fusion had only demonstrated that research can continue
even if the phenomena doesn't actually exist, as long as there is funding
available. Taubes had previously written an article for Science in which he
insinuates that the cold fusion work of A &M University was fraudulent._

------
gammarator
This result is from a legitimate experimental group. It's much more likely to
be experimental error than new physics, though: previous observations of
neutrinos coincident with the light emitted by supernova 1987a (much, much
farther away) indicate that neutrinos travel at light speed to 1 part in 10^8
[1,2]

[1] <http://adsabs.harvard.edu/abs/1989ARA%26A..27..629A> [2]
[http://blogs.discovermagazine.com/badastronomy/2011/09/22/fa...](http://blogs.discovermagazine.com/badastronomy/2011/09/22/faster-
than-light-travel-discovered-slow-down-folks/)

Also, <https://www.xkcd.com/955/>

------
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...](http://www.guardian.co.uk/science/2011/sep/23/physicists-speed-light-
violated)

~~~
Jach
Neither sound very good to me, nor are they really explanations. "Hidden" is
just as bad as "magic" here. And isn't the second basically the standard
aether theory that was soundly defeated at least 100 years ago?
<http://en.wikipedia.org/wiki/Michelson-Morley_experiment>

------
sprovoost
My guess is there's something wrong with the statistical modeling, but I
realize that's not a very useful statement. I missed the press conference, but
I did read the paper and I even understood a few things. :-) It was good to
see they even thought about seismic activity (centimeters). One thing I
noticed in both the article and the media is that the effect is never
expressed in terms of distance (about 15 meters), but only in terms of time
and speed. It surprises me that they're able to determine the point of
creation and detection of neutrinos in such huge instruments, but of course
they know their stuff. I did get the impression it took a lot of modelling and
advanced statistics to achieve that, hence my earlier "gut feeling" that there
lies the problem.

A few other possible explanation that crossed my mind and I'm sure are wrong
and already thought about:

* the distance between both sides was measured very accurately, _above ground_. The earth is not flat, so the distance underground is shorter. I'm too tired to calculate how much shorter.

* relatistic effect of the beam going deeper underground on its way over; I read elsewhere that they already considered the effect of altitude difference between the two stations and that it was orders of magnitude smaller.

* some other mistake in distance measurement; have they tried sending other, easier to measure, signals over to figure out the distance? Or some other independent way to measure that distance?

~~~
libria
D of earth = 12756km, and assuming a sphere (my physics prof would be proud),
I'm computing that 730km covers a ~6.6 degree arc. Also assuming a 100m
underground tunnel, the distance would be 21m shorter than its above-ground
measurement. Someone needs to recheck my math, though.

~~~
sprovoost
According Arethuza's comment below, at least one of the labs is 1400 meters
below ground. Also you need to calculate the straight-line distance between
the two points, not the distance over the surface. Although for calculating
the difference that's probably a good enough approximation. So if both
stations are 1400 deep and your calculation is correct, the difference should
be 14x21=300 meters. Which is a lot more than the 15m effect they found, which
suggests they thought about this.

------
ivan_ah
I watched the news conf. this morning.

The neutrino production "curve" looks like a a square wave pulse as a function
of time

____| |_____

and the detection points look like this

___________________________________| |_____

with ∆t ~= 700km/c time distance between the two pulses.

The claim is that the "most likely guess" of the received pulse shape
(obtained from many measurements) is too far right to be consistent with speed
of light, but the ∆t measured where?

between the onset of the pulses? between the place where the pulses go down?

What they did some mega calculation (maximum likelihood stuff), to predict the
best approximation to the shape of the pulse at the receiving end -- so
somehow they take on the approximation of the whole pulse (which is much wider
than the claimed discrepancy).

They should downgrade the claim from: "speed of neutrinos is...." to: "speed
of pulses of neutrinos ..... on average, as predicted by the maximum likely
shape of the pulse", which sounds much less profound.

The conf was good though, the speaker stood up to a lot of serious scrutiny.
My guess is the problem is with the ML curve shape calculation.

~~~
lutorm
_They should downgrade the claim from: "speed of neutrinos is...." to: "speed
of pulses of neutrinos ..... on average, as predicted by the maximum likely
shape of the pulse", which sounds much less profound._

This would apply to every paper in existence. If you want to know the
methodology, you read that section of the paper. Putting it in the title only
obscures the message.

It's true that it makes the analysis a lot harder, and one of the questions
after the talk was about making shorter bunches of neutrinos. The duration of
the pulses are probably just set by the width of the proton bunches in the
ring, in which case it would be nontrivial to make it much shorter.

------
arethuza
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>

~~~
narag
Is this needed? Or could the reception be done in the surface?

I mean, the interesting question is now: how much time will it take to repeat
the experiment, either by others or by the CERN but with other reception
point?

------
joeyespo
From the release, there's a live webcast going on right now (16:00 CEST, Sept
23) at: <http://webcast.cern.ch/>

~~~
jasonkeene
I so LOL'd when someone in the webinar pointed out that their measurement
wasn't a vector so their paper should be titled neutrino speed not velocity.
<http://arxiv.org/abs/1109.4897>

~~~
nooneelse
They know where the neutrinos were produced and where they were detected 730km
away. That seems like enough for a pretty good guess at their direction of
travel. But I guess they didn't really present that aspect of things.

------
simplegeek
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.

~~~
nirvana
My background is in physics and one of my first programming jobs was writing
code for a lab of international importance. At the time, I would engage the
other members of the lab in an ongoing debate about Einstein, where I'd take
the position that Einstein was wrong (About anything, or everything, whatever
the handy topic was.) I was, and am, an Einsteinian skeptic.

I learned a lot in that, and one thing that actually surprised me is that in
many cases, I was able to make a good argument that Einstein was wrong, and
there was no empirical evidence to support his view on the particular point we
were discussing.

The point of that is not that I believe Einstein was wrong. It is that this is
not a situation where any single experimental result can show that the theory
doesn't hold, or does hold. There are many experiments where his theories do
seem to hold (though I enjoyed poking holes in them). If this result is
repeatable and turns out to be correct, it will cause many physicists to re-
evaluate many theories, and have huge implications.

Einsteins work resulted in many theories, and of course a grand set of them
called relativity (and special relativity)... the media simplifies this to
"nothing can move faster than the speed of light".

I can see the situation where this causes an adjustment in the specific
interpretations of his theories. Or it could turn out that these results are
both true, and consistent with his theories. For instance, prior to the
understanding of matter there were many theories about mass that are
essentially true on the macroscopic scale, though once you understand that
matter is made up of atoms you see where they don't hold on the microscopic
scale.

This result could reveal a level of reality beyond what Einstein understood,
such that he's right from our macroscopic scale, but there's a whole other
branch of physics in there.

So, I'm not declaring victory. I think this is good news, though, because it
might be the beginning of the revelation of an error in understanding that,
when resolved, results in a big jump forward in physics.

PS- I'm not interested in getting into a physics debate. Its been too many
years, and I've spoken vaguely because the specifics are not what I'm
addressing.

~~~
hugh3
You _do_ realize that proving "Einstein was wrong" is a favourite activity of
the many physics cranks who hang around sending letters to physics departments
year in year out?

And that of all the thousands of folks who have claimed to have a "proof" that
relativity is wrong, the they break down as about seventy percent simple
misconceptions and thirty percent complete nonsense, with the remainder being
zero?

 _At the time, I would engage the other members of the lab in an ongoing
debate about Einstein, where I'd take the position that Einstein was wrong
(About anything, or everything, whatever the handy topic was.) I was, and am,
an Einsteinian skeptic._

It's a good thing you left physics for programming, because it doesn't sound
like you have a particularly strong commitment to scientific principles. To
get a Nobel Prize it would be perfectly sufficient to show convincingly that
Einstein was wrong about _one_ thing [insert caveats here, obviously I don't
mean trivial things]. If you believe Einstein was wrong about "anything and
everything" then you're just committing the cardinal sin of believing things
because you _want_ them to be true, rather than because there's sufficiently
convincing evidence that they're true.

~~~
MarkPNeyer
believing in something to be the truth, no matter how much 'convincing
evidence' there is to support that conclusion, isn't really a scientific
princple. skepticism, on the other hand, most certainly is.

science isn't about believing in anything to be the truth; it's about
constructing analytical models that make accurate predictions while
consistently exercising skepticism about the ability of any model to do so.

~~~
hugh3
Yes, the English language really lacks the vast suite of words we need in
order to express our degrees of certainty about things. Words such as "know",
"believe", "think" and "suspect" don't express these things properly, but we
have to make do with what we have.

I don't think that "believe" is a particularly bad word for the relationship
of a rational person to a fairly well established fact, though. I believe, for
instance, that the Earth has an iron-nickel core. I fully acknowledge the
possibility that it might not, and am fully ready to change that belief based
on new evidence, but I think it's fairly well established and I am willing to
act as if it were true.

------
jchrisa
lotsa basic FTL stuff here if people wanna get a broad picture
<http://www.weburbia.com/physics/FTL.html>

~~~
hugh3
That's a pretty good summary. It progresses from "things that might seem to be
FTL but don't really count" through "things that are kinda sorta FTL in some
sense but still don't carry any information" and into "highly speculative
things which could potentially be properly FTL but haven't been shown to be
possible".

------
mladenkovacevic
A great article on various disagreements between Tesla's and Einstein's view
of the physical world.

[http://www.writingriffs.com/2009/09/13/tesla-vs-einstein-
tra...](http://www.writingriffs.com/2009/09/13/tesla-vs-einstein-transcending-
the-speed-of-light-with-author-marc-seifer/)

Will Tesla have the last laugh?

~~~
podperson
Not based on the linked article, which is horrible. I gave up when it was
simultaneously trying to claim that the ether exists but space can have no
properties.

~~~
viscanti
The author could have done a better job of explaining this, if he would have
said "Einsteinian Space" rather than "space" in that section. That's fairly
easy to infer from the context, but it could have been explained better.
Einstein viewed "space" as a vacuum. Tesla argues that view is flawed, that
nothingness by definition can't have any properties, and as a result can't
bend, because there's nothing to bend. He proposes aether/ether as an
alternative explanation of "space".

~~~
podperson
If all that we're talking about is terminology then the entire article is
pointless.

------
guelo
This article from a couple days ago did a good job of dampening any wild hopes
[http://io9.com/5843112/faster-than-light-neutrinos-not-so-
fa...](http://io9.com/5843112/faster-than-light-neutrinos-not-so-fast)

A probably nonsensical idea about the super-nova point they make: maybe what
it means isn't that neutrinos are traveling faster than light but that they
are traveling just ahead of light. In other words, they are some kind of shock
wave moving through space at speed c but at a location just slightly ahead of
the disturbance. Maybe we are detecting the supernova neutrinos a few nano
seconds before when we're supposed to be.

Still, it's probably a measurement error.

------
TeMPOraL
<http://xkcd.com/812/> \- relevant xkcd.

------
Symmetry
The path from the things people observed to "and neutrinos travel faster than
light" travels down a long string of inferences. Inferences about the
equipment working properly and inferences about other aspects of physical law.

Most likely this is a problem with the equipment. I'm sort of hoping that some
other aspect of our knowledge of physics has been revealed to be off, though,
since that is where real progress comes from.

It might even be that the most straightforward but most improbable case is
right, and these neutrinos actually are traveling faster than light. That
would be awesome, but also terrifying since then its only a matter of
technology to get a device that would permit communication with the past.

------
gfaremil
Does anybody know why they were doing this experiment (measuring speed fo
neutrinos) at all? Were they assuming that neutrinos travel faster than speed
of light in the first place?

~~~
LXicon
as i understand it, they were doing experiments to watch how neutrinos change
between "electron", "muon" and "tau" flavors. the timing of when the neutrino
was sent from cern and viewed by the experiment was required to match what the
neutrino was before and after.

------
hernan7
Do they at any time say how much faster than light are those neutrinos moving?
1% faster? 100 times faster? I couldn't see that info anywhere.

~~~
thoradam
0.002% faster.

~~~
sneak
+/- 0.002%

~~~
Arjuna
"+/- 0.002%"

How did you derive a negative bound? A negative bound suggests that arrival
times could be slower than _c_.

The paper indicates that arrival times are _always faster than c_.

From the paper:

 _"An early arrival time of CNGS muon neutrinos with respect to the one
computed assuming the speed of light in vacuum of (60.7 ± 6.9 (stat.) ± 7.4
(sys.)) ns was measured."_

~~~
sneak
Perhaps my one-word comment was an insufficient indicator of my sarcasm.
't'was a joke, good sir.

------
mrb
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 am wrong, but just throwing this out there :)

~~~
lutorm
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.

~~~
mrb
I am talking about the presence of the gravitational field, not its difference
between the 2 sites. Anyway, I calculated gravitational time dilation on Earth
out of curiosity. It has an effect of only about 1e-9.

------
shimsham
inches vs centimetres. damn those units.

