## 0955: "Neutrinos"

This forum is for the individual discussion thread that goes with each new comic.

Moderators: Moderators General, Magistrates, Prelates

### 0955: "Neutrinos"

Title text: "I can't speak to the paper's scientific merits, but it's really cool how on page 10 you can see that their reference GPS beacon is sensitive enough to pick up continential drift under the detector (interrupted halfway through by an earthquake)."

Am I getting old? The font in the bottom box of the 2nd panel is a bit small I think.

Edit: I don't like placeholders
Last edited by Vrishna on Fri Sep 23, 2011 7:36 am UTC, edited 1 time in total.
Wanna find out my Christian name? Can you guess by looking at this Perl code?
Code: Select all
$e=length(open(S,$0).<S>);$GM=!$l||9;for(join$v,<S>){$m=join$w,/\$(\w)/gm;for(split/$xxx/,$m){print chr(ord()-$e/7);}}if($r){exit}

Vrishna

Posts: 17
Joined: Mon Dec 21, 2009 9:17 am UTC
Location: Germany

### 0955: "Neutrinos"

Alt Text: I can't speak to the paper's scientific merits, but it's really cool how on page 10 you can see that their reference GPS beacon is sensitive enough to pick up continential drift under the detector (interrupted halfway through by an earthquake).
I didn't find it as funny, but I thought the comment about GPS picking up continental drifts+ earthquake was interesting.
http://xkcd.com/955/
sardia

Posts: 1807
Joined: Sat Apr 03, 2010 3:39 am UTC

### Re: 0955: "Neutrinos"

toastedcrumpets wrote:
mania wrote:Kind of wondering if Randall's making one on the possible discovery of tachyonic neutrinos announced overnight...

Nah, the comic would have arrived slightly earlier than usual if that was the case......

Nice guess

J L

Posts: 197
Joined: Mon Jan 25, 2010 11:03 am UTC
Location: Germany

### Re: 0955: "Neutrinos"

Damn, 5 minutes too slow.
sardia

Posts: 1807
Joined: Sat Apr 03, 2010 3:39 am UTC

### Re: 0955: "Neutrinos"

Thought the same about the font and then went on to be upset about the lack of forum thread and the fact that I can not use url-tags in my posts (and therefore can't create a proper thread)

Also the comic picture links to comic 9gg...
e02jr

Posts: 2
Joined: Wed Sep 30, 2009 5:45 am UTC

### Re: 0955: "Neutrinos"

What are the implications of this? Faster than light communications utilizing neutrinos?
Brooks Hatlen

Posts: 25
Joined: Tue Feb 15, 2011 5:47 am UTC

### Re: 0955: "Neutrinos"

J L wrote:
toastedcrumpets wrote:
mania wrote:Kind of wondering if Randall's making one on the possible discovery of tachyonic neutrinos announced overnight...

Nah, the comic would have arrived slightly earlier than usual if that was the case......

Nice guess

Thank you.. have to say, Toastedcrumpets reply was golden
mania

Posts: 24
Joined: Sat Sep 20, 2008 9:44 am UTC

### Re: 0955: "Neutrinos"

e02jr wrote:Also the comic picture links to comic 9gg...

Sorry for that. Some ill-routed neutrinos must have hit the keyboard cable very hard while I was typing that. (Corrected it.)
Wanna find out my Christian name? Can you guess by looking at this Perl code?
Code: Select all
$e=length(open(S,$0).<S>);$GM=!$l||9;for(join$v,<S>){$m=join$w,/\$(\w)/gm;for(split/$xxx/,$m){print chr(ord()-$e/7);}}if($r){exit}

Vrishna

Posts: 17
Joined: Mon Dec 21, 2009 9:17 am UTC
Location: Germany

### Re: 0955: "Neutrinos"

Sorry to be a noob, but I dont get the alt-text, could someone explain it please
goibee

Posts: 5
Joined: Wed Aug 10, 2011 3:19 pm UTC

### Re: 0955: "Neutrinos"

A link to the actual paper: http://arxiv.org/abs/1109.4897

The alt text was being literal. From page 10:
The high-accuracy time-transfer GPS receiver allows to continuously monitor tiny movements of the Earth’s crust, such as continental drift that shows up as a smooth variation of less than 1 cm/year, and the detection of slightly larger effects due to earthquakes. The April 2009 earthquake in the region of LNGS, in particular, produced a sudden displacement of about 7 cm, as seen in Fig. 7. All mentioned effects are within the accuracy of the baseline determination. Tidal effects are negligible as well.
Sandor

Posts: 94
Joined: Sat Feb 13, 2010 8:25 am UTC

### Re: 0955: "Neutrinos"

Any xkcd-ers feel like dumbing down the paper and its significance for some of their less intelligent fellow users (a.k.a. me )
"An eye for an eye leaves the whole world blind" -Ghandi

Wrong. All that does is eliminate humanity's depth perception.

xX17GHDUDE17Xx

Posts: 29
Joined: Wed Feb 09, 2011 4:44 am UTC

### Re: 0955: "Neutrinos"

Hi everyone.

Is it me or this experiment just demonstrates the Cherenkov effect ?

I can't see what's new there ...
ashaku

Posts: 2
Joined: Fri Sep 23, 2011 8:28 am UTC

### Re: 0955: "Neutrinos"

xX17GHDUDE17Xx wrote:Any xkcd-ers feel like dumbing down the paper and its significance for some of their less intelligent fellow users (a.k.a. me )

If I try, I'm not sure I'll do a very good job at it. But here's some articles from writers who are fairly good at explaining things..
http://io9.com/5843112/faster-than-ligh ... ot-so-fast

mercuryseven

Posts: 208
Joined: Mon Nov 23, 2009 8:36 am UTC

### Re: 0955: "Neutrinos"

I only read this story this morning - 'cos I was so disappointed that xkcd was updated yet, I looked through some news sites while drinking my coffee. Definitely worth waiting for.
yangosplat wrote:So many amazing quotes, so little room in 300 characters!
NotAllThere

Posts: 93
Joined: Fri Aug 06, 2010 12:54 pm UTC

### Re: 0955: "Neutrinos"

I like the alt-text.

Resonant depolarisation measurements in LEP were so sensitive to geophysical movement (which would literally squash or move the accelerator by a miniscule amount) that it had to be corrected against (and could actually be used to measure) the tidal forces from the position of the moon, and the amount of water in Lake Geneva.
...suffer from the computer disease that anybody who works with computers now knows about. It's a very serious disease and it interferes completely with the work. The trouble with computers is you play with them. They are so wonderful. - Richard Feynman

Minerva

Posts: 896
Joined: Sat Nov 11, 2006 2:58 pm UTC
Location: Australia

### Re: 0955: "Neutrinos"

I am surprised that no-one has mentioned Fleischmann and Pons yet. I admit this would be a more serious matter than the existence of cold fusion, but if there is an issue with reproducing the experiment, the situation would be fairly similar
ygp

Posts: 12
Joined: Fri Sep 23, 2011 9:52 am UTC

### Re: 0955: "Neutrinos"

The bad thing about the measurement is that they have only one distance. If any part of the timing is wrong by 60ns, the measurement is screwed. A different baseline would help to see f it is a different speed (different delta t) or a timing problem (same delta t).
mfb

Posts: 803
Joined: Thu Jan 08, 2009 7:48 pm UTC

### Re: 0955: "Neutrinos"

I've heard no one hear the news and claim that relativity doesn't exist. However if the paper is correct in every particular then it is true that the theory of relativity must be wrong in some particular. I don't really see the funny side of this comic (in fact I don't know whether half these new comics are supposed to have a humourous side or whether they're just opportunities for Randall to show off). Only really really stupid people would take a bet like that and though mocking stupid people can be fun, I have to say I thought Randy was past it.
thearbiter

Posts: 14
Joined: Mon Aug 02, 2010 10:42 am UTC

### Re: 0955: "Neutrinos"

I'm sure some scientist out there is going to put me on his list to "permanently reeducate", but here goes

Why are Einstein's predictions, and the subsequent evidential experiments, held to be completely-and-unrevokably-undeniably-set-utterly-in-stone-never-to-be-proven-wrong-or-that-any-workarounds-or-alternatives-exist-to-circumvent-the-scientific-proofs?

My position is that we have consistently throughout history set boundaries on things, and we have deemed those boundaries to be non-arbitrary in nature - only to have those boundaries knocked down by later advances and new boundaries put in their place.

For Einstein (and subsequent experimental proof) to set the entire universe in stone with his predictions, at a time when we still didn't know so much about the universe (and still don't know so much) seems a little ... naive, surely?

I'm not denying that Einstein and his predictions aren't true, but to say that they offer a very hard boundary that shall never be crossed is, to me, a little reaching - as an example, Newtons theories were proven to be too simplistic even after acting as an extremely good base for science for centuries.

For me, its like saying a 9 year old child has a complete grasp of social dynamics that will never change through their life, and they have that grasp because of the understanding of the world around them. Of course their understanding, and their rules, will change as they experience more about the world.

Now, it may be that the actual scientific community don't actually feel the way that the media seem to portray them ("this can't happen, ever" style of thought), and if this is the case then please understand Im not being confrontational, just interested
RichardPrice

Posts: 4
Joined: Fri Sep 23, 2011 10:35 am UTC

### Re: 0955: "Neutrinos"

The mouse-over here is awesome- we use continuous GPS recievers all over the world to measure how fast and where the continents are moving and also to study exactly why they move as they do. It's pretty cool to be a geologists and I'm glad that Randall notices these things!
mountain_girl

Posts: 2
Joined: Fri Sep 23, 2011 10:49 am UTC

### Re: 0955: "Neutrinos"

ashaku wrote:Hi everyone.

Is it me or this experiment just demonstrates the Cherenkov effect ?

I can't see what's new there ...

The way I understand it, in a Cherenkov radiation, even though the particles move faster than photons in the same medium, they still move slower than c (speed of light in vacuum).

The recent experiment showed us that those neutrinos traveled faster than c, or specifically: 1.000025*c
resshin

Posts: 5
Joined: Sun Nov 22, 2009 12:44 pm UTC

### Re: 0955: "Neutrinos"

I had to read the second panel twice before I realized the word was "Galileo," not "gauled."
RoeCocoa

Posts: 4
Joined: Tue Apr 19, 2011 3:39 pm UTC

I don't really like to argue with people, but I'll argue with you if you pay me $200 a throw. jpk Posts: 464 Joined: Sat Nov 13, 2010 7:33 am UTC ### Re: 0955: "Neutrinos" As a geologist, the tooltip for this comic (and the figure caption in the paper) really irked me. GPS stations are used all the time in geology/geodesy. They have been used to measure gross tectonic plate motion and local strain accumulation along plate margins and major faults, among many other things. However, they do not measure "continental drift"! Continental drift was a theory of Earth evolution in which the continents "plowed" through the oceanic plates. This theory was postulated by Alfred Wegener in the 1910s. During the 1960's, the theory of Plate Tectonics was formed and it continues to be the accepted theory for the crustal evolution of Earth. Plates don't drift, they move, subduct (dive under each other), and collide as a collective whole. As for the comment that the GPS "picks up the motion under the detector", the GPS station along with the detector are moving the same speed and direction. The ground isn't moving beneath the detector, they are moving together, as a system. mkfrancsis Posts: 1 Joined: Fri Sep 23, 2011 12:26 pm UTC ### Re: 0955: "Neutrinos" RichardPrice wrote:For Einstein (and subsequent experimental proof) to set the entire universe in stone with his predictions, at a time when we still didn't know so much about the universe (and still don't know so much) seems a little ... naive, surely? I'm not denying that Einstein and his predictions aren't true, but to say that they offer a very hard boundary that shall never be crossed is, to me, a little reaching - as an example, Newtons theories were proven to be too simplistic even after acting as an extremely good base for science for centuries. Einstein did not set the entire universe in stone, there are lots of questions unanswered by his theory. But his theory is tested so well that it is very very unlikely that the basis of his theory (nothing faster then light) is wrong. Newton wasnt wrong, just not precise enough in every case. This might be true for Einstein too, but if massive particles could be faster then light that would not mean that we need a correction term here and there, but that Einseins theory is wrong on a fundamental level. And that is too unlikely since too many experiments proved his theory right. Myta Posts: 2 Joined: Wed Dec 31, 2008 1:07 am UTC ### Re: 0955: "Neutrinos" Lightspeed is fast, neutrinos are fast, and so is xkcd. llwang Posts: 7 Joined: Fri Sep 10, 2010 4:42 am UTC ### Re: 0955: "Neutrinos" mkfrancsis wrote:As a geologist, the tooltip for this comic (and the figure caption in the paper) really irked me. GPS stations are used all the time in geology/geodesy. They have been used to measure gross tectonic plate motion and local strain accumulation along plate margins and major faults, among many other things. However, they do not measure "continental drift"! Continental drift was a theory of Earth evolution in which the continents "plowed" through the oceanic plates. This theory was postulated by Alfred Wegener in the 1910s. During the 1960's, the theory of Plate Tectonics was formed and it continues to be the accepted theory for the crustal evolution of Earth. Plates don't drift, they move, subduct (dive under each other), and collide as a collective whole. As for the comment that the GPS "picks up the motion under the detector", the GPS station along with the detector are moving the same speed and direction. The ground isn't moving beneath the detector, they are moving together, as a system. Actually, mkfrancsis, we've also known for quite a long time (1980's, England, Molnar, McKensie, etc.) that the continents don't deform according to plate tectonics. Plate tectonics says that the plates deform at the edges and not internally. The continents deform internally (just look at the convergence of India and Asia- Asia is deforming over 2500 km away from the Indian margin!), so it's actually not the accepted theory for the continents, and Italy is continental crust, so it's not behaving under the rules of plate tectonics. I wouldn't expect a non-geologist to know this, just like I wouldn't expect them to know the difference between plate tectonics and continental drift, but I would expect a geologist to know this (presumably you're a geologist?). I just like to appreiciate the fact that Randall thought it was so cool that we can measure this... I thought it was just as awesome when I first learned about GPS geodesy many years ago! Last edited by mountain_girl on Fri Sep 23, 2011 1:13 pm UTC, edited 1 time in total. mountain_girl Posts: 2 Joined: Fri Sep 23, 2011 10:49 am UTC ### Re: 0955: "Neutrinos" jpk wrote: userxp wrote:The idea in the comic wouldn't work. In order to get the$200 they owe you, they would have to admit that they lost the bet. So you'd have to argue with them that they were wrong, and then it's the same thing all over again .

I don't really like to argue with people, but I'll argue with you if you pay me \$200 a throw.

But you'll only get paid if you manage to have these "excited believers" (read: probably fanatics) admit that they were wrong.

-"See? The very authors admitted that their paper was flawed!"
-"But they could be wrong! That doesn't prove that it's not true!"
-"Every single scientific observation done in the last century is evidence that you are wrong!"
userxp

Posts: 436
Joined: Thu Jul 09, 2009 12:40 pm UTC

### Re: 0955: "Neutrinos"

Myta wrote:
Einstein did not set the entire universe in stone, there are lots of questions unanswered by his theory. But his theory is tested so well that it is very very unlikely that the basis of his theory (nothing faster then light) is wrong. Newton wasnt wrong, just not precise enough in every case. This might be true for Einstein too, but if massive particles could be faster then light that would not mean that we need a correction term here and there, but that Einseins theory is wrong on a fundamental level. And that is too unlikely since too many experiments proved his theory right.

That is a good point, and some form of systemic error is most likely, but from my (admittedly) unschooled glance, it appears as though their ducks are in a row. They didn't use just one result and shout we destroyed Einstein. I guess we need to wait and see how and if it can be repeated and if perhaps pouring over the results of older experiments could provide some corroboration. The data might be there to support it, but had been tossed out as "obviously wrong" since it contradicted 'c'.
JPatten

Posts: 18
Joined: Tue Jul 13, 2010 5:39 pm UTC
Location: Southeast USA

### Re: 0955: "Neutrinos"

Yeah, we need to reproduce the experiment and try it again with a different setup. I'm leaning toward error.
On the other hand, science just went, "Huh, that's funny." ( http://www.schlockmercenary.com/2002-05-28 )
Aubri

Posts: 9
Joined: Mon Mar 28, 2011 2:28 pm UTC

### Re: 0955: "Neutrinos"

Myta wrote:
Einstein did not set the entire universe in stone, there are lots of questions unanswered by his theory. But his theory is tested so well that it is very very unlikely that the basis of his theory (nothing faster then light) is wrong. Newton wasnt wrong, just not precise enough in every case. This might be true for Einstein too, but if massive particles could be faster then light that would not mean that we need a correction term here and there, but that Einseins theory is wrong on a fundamental level. And that is too unlikely since too many experiments proved his theory right.

And your post basically proves my point - people accept Einsteins theory as a hard boundary, and continue to support it as a hard boundary, when the reality is that we are still the equivilent of the 9 year old in my post.

How much do we actually know about the universe around us? Do we know enough to say without a shadow of a doubt that the experiments we are running to test Einstein are the correct experiments, and we aren't just unwittingly carrying out the wrong experiments?

Yeah, I know, I'm sounding like one of those crackpots I love to hate, but still...

Its one of my pet hates when someone uncategorically says something is impossible and will remain impossible - as a civilisation, our history is short enough that we still have in actual living memory the experiences of what it was like to not have computers, to not have modern medicine, to not have nuclear weapons, to not be able to create life in a test tube etc etc. Go back a little further and you have people resoundly saying a lot of our modern way of life is impossible. Go back even further and it gets funnier and funnier.

Should we really view Einsteins theories as a hard, uncompromising limit on the universe?
RichardPrice

Posts: 4
Joined: Fri Sep 23, 2011 10:35 am UTC

### Re: 0955: "Neutrinos"

Aubri wrote:Yeah, we need to reproduce the experiment and try it again with a different setup. I'm leaning toward error.
On the other hand, science just went, "Huh, that's funny." ( http://www.schlockmercenary.com/2002-05-28 )

The actual quote being:

The most exciting phrase to hear in science, the one that heralds new discoveries, is not 'Eureka!' but 'That's funny...' - Isaac Asimov

Its one of my favourites, because its so true.
RichardPrice

Posts: 4
Joined: Fri Sep 23, 2011 10:35 am UTC

### Re: 0955: "Neutrinos"

Hey. I posted a thread in the math section (pending approval) that is semi-relevant to FTL transport.
To cut things short, I had a bar conversation with a Technical Physicist from DTU. We talking about Tyson and a few other subjects. Weeellll, I doubt we could use mathematics to talk with aliens on any level for a host of reasons, such as they have no prior knowledge of the symbols we use or the axioms we assume, except for the cavet of independent discovery.

What if the axiom, the shortest distance between two points is a straight line, is not true in a curve space time of n dimensions?

Hell, why assume the shortest distance is the same for all particles and waves?
iPyramid

Posts: 5
Joined: Fri Sep 23, 2011 1:18 pm UTC

### Re: 0955: "Neutrinos"

I did never get why everyone thinks that relativity HAS to be right anyway. After all, it makes two assumptions that are AFAIK impossible to prove: That the speed of light in vacuum is constant and that the laws of physics work the same in every frame of reference.
For the first:
c=\sqrt{{1}\over{\epsilon_0\cdot\mu_0}}

but who can be sure that the fundamental constants of nature are really constant and that \epsilon_0 and \mu_0 have always had the same values?
And for the second: Isn't that even a contradiction to the multiverse interpretation of quantum physics, where the same thing can have different outcomes?

DISCLAIMER: I'm not a physicist.
I'm not even a scientist.
cemper93

Posts: 137
Joined: Sun Feb 20, 2011 2:35 pm UTC

### Re: 0955: "Neutrinos"

My favourite comment so far RT by @SciAm on Twitter: @dcastelvecchi:
Would Opera results be more proper titled "Distance measurement using neutrinos, the most accurate available, shows other methods were off"?

For a great easy read on the methodology see http://scienceblogs.com/startswithabang/2011/09/this_extraordinary_claim_requi.php (though it doesn't talk to the accuracy of distance measurement).

greenlimabeans

Posts: 1
Joined: Fri Sep 23, 2011 1:59 pm UTC
Location: Cape Town, South Africa

### Re: 0955: "Neutrinos"

RichardPrice wrote:Should we really view Einsteins theories as a hard, uncompromising limit on the universe?

I can't speak for the media, or the common person, (or really the scientific community either) but the scientific community doesn't view Einstein as complete truth.

Consider it this way: Either Einstein or this new study has made an error. Einstein's theories have a lot more supporting evidence, therefore it is far more likely for this study to be in error. Therefore the scientific community will now try to find that error. If the new study is in fact correct, they will not find an error, and will become strong enough that it will become more likely that Einstein made the error. Then the scientific community will devote their time to trying to find Einstein's error.

Einstein's theories aren't regarded as true, they're regarded as most likely to be true. Same as Newton before him.

Posts: 29
Joined: Wed May 25, 2011 4:50 am UTC

### Re: 0955: "Neutrinos"

I came here for the first time looking for a little information on the study and wondered whether Randall intended the comic to extend to its own thread. Reread the comic, then read your somewhat pedantic posts here

p.s. I've got 200 - anyone?
jschwartzbeck

Posts: 3
Joined: Fri Sep 23, 2011 2:18 pm UTC

### Re: 0955: "Neutrinos"

resshin wrote:The way I understand it, in a Cherenkov radiation, even though the particles move faster than photons in the same medium, they still move slower than c (speed of light in vacuum).

The recent experiment showed us that those neutrinos traveled faster than c, or specifically: 1.000025*c

Wow, that is interesting. I was looking at the paper and saw the equation (v-c)/c = 2.48 * 10^-5 (with an error band) and I automatically read that backwards, that the beam was slightly slower than light. Which would mean nothing to see here...

But being slightly faster...

My take on this:
1) Vacuum is not really vacuum, there is a bit of hydrogen in empty space, something like 1 atom per cubic meter.
2) We already know light slows down based on the index of refraction of the medium. That's how lenses work.
3) I'd interpret this to mean neutrinos really do travel at the maximum speed information can propagate.
4) We ought to start saying, "Faster than neutrinos!" instead of "Faster than light!"
If my wife were a D&D character she'd be all 10's

dash

Posts: 67
Joined: Sat Mar 08, 2008 4:05 am UTC

Next