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Chameleon-Like Behavior of Neutrino Confirmed

Soulskill posted more than 4 years ago | from the yes,-neutrinos-eat-bugs dept.

Science 191

Anonymous Apcoheur writes "Scientists from CERN and INFN of the OPERA Collaboration have announced the first direct observation of a muon neutrino turning into a tau neutrino. 'The OPERA result follows seven years of preparation and over three years of beam provided by CERN. During that time, billions of billions of muon-neutrinos have been sent from CERN to Gran Sasso, taking just 2.4 milliseconds to make the trip. The rarity of neutrino oscillation, coupled with the fact that neutrinos interact very weakly with matter, makes this kind of experiment extremely subtle to conduct. ... While closing a chapter on understanding the nature of neutrinos, the observation of neutrino oscillations is strong evidence for new physics. The Standard Model of fundamental particles posits no mass for the neutrino. For them to be able to oscillate, however, they must have mass.'"

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Who would have guessed (0)

Anonymous Coward | more than 4 years ago | (#32411364)

Something missing from the Standard Model?
Shocking!

Re:Who would have guessed (5, Funny)

NotQuiteReal (608241) | more than 4 years ago | (#32411430)

Nobody every buys the Standard Model. If you have the money you get the Luxury Model. Otherwise, most folks just aim for the middle and get the Sports model.

Re:Who would have guessed (1)

Fieryphoenix (1161565) | more than 4 years ago | (#32412448)

Don't forget the Executive model.

No. (1, Insightful)

gbutler69 (910166) | more than 4 years ago | (#32411460)

Something PROVED TO BE missing from the Standard Model? Shocking!^H^H^H^H^H^H^H^H INTERESTING

There, fixed that for you

Re:No. (-1, Troll)

Anonymous Coward | more than 4 years ago | (#32411888)

Something PROVED TO BE missing from the Standard Model? Shocking!^H^H^H^H^H^H^H^H INTERESTING

There, fixed that for you

Why does San Francisco have so many fags while Harlem has so many niggers?

San Francisco got first choice.

What if... (0)

Anonymous Coward | more than 4 years ago | (#32411454)

they don't have mass but still oscillate?

Re:What if... (5, Informative)

Steve Max (1235710) | more than 4 years ago | (#32411522)

You'd need a pretty complex theory to get non-mass oscillations to match all the data we got over the past 12 years, which is very compatible with a three-state, mass-driven oscillation scenario. Besides, you'd have to explain more than what the current "new standard model" (the SM with added neutrino masses) does if you want your theory to be accepted. If two theories explain the same data equally well, the simplest is more likely.

Re: What if... (2, Informative)

Black Parrot (19622) | more than 4 years ago | (#32411716)

If two theories explain the same data equally well, the simplest is more likely./quote?
Make that "more preferred". In general we don't know anything about likelihood.

The thing about Occam's Razor is that it filters out "special pleading" type arguments. If you want your pet in the show, you've got to provide motivation for including it.

Re: What if... (1)

Steve Max (1235710) | more than 4 years ago | (#32411896)

Thanks, good catch.

Re:What if... (1)

dimeglio (456244) | more than 4 years ago | (#32411722)

This is not a theory. It was demonstrated experimentally.

Re:What if... (0)

Anonymous Coward | more than 4 years ago | (#32411830)

What is "this" and "it" in your sentence? Neutrino oscillations were demonstrated experimentally. Neutrino mass was not. The dispute is over the statement "neutrino oscillation implies mass", which is a theory.

Re:What if... (1)

Zaphod The 42nd (1205578) | more than 4 years ago | (#32411946)

You misunderstand the word theory.

Re:What if... (2, Funny)

Anonymous Coward | more than 4 years ago | (#32411872)

God did it.

Re:What if... (1)

euxneks (516538) | more than 4 years ago | (#32412418)

If two theories explain the same data equally well, the simplest is more likely.

Is that really the case? That seems like it's a very hominid-centric assumption. I can't think of any counter examples but it seems very naïve to assume that the nature of the Universe would be simple...? Though, perhaps my understanding is limited.

Example: Relativity vs Newton (2, Insightful)

syousef (465911) | more than 4 years ago | (#32412446)

If two theories explain the same data equally well, the simplest is more likely.

Is that really the case? That seems like it's a very hominid-centric assumption. I can't think of any counter examples but it seems very naïve to assume that the nature of the Universe would be simple...? Though, perhaps my understanding is limited.

Well it's VERY difficult to detect relativistic effects at human walking speed but they are still there. So you could create a whole stack of data that supports Newtonian physics over Relativity on that basis, but Relativity, though more complex is a more accurate description of the Universe.

When something doesn't fit your model, more experimentation and experience is needed, and most importantly you may need to do DIFFERENT experiments to determine whether a simpler or more complex theory is more accurate.

Re:What if... (5, Insightful)

Steve Max (1235710) | more than 4 years ago | (#32412628)

The point is that, if two different theories have the exact same predictions, they are for all intents and purposes the same theory, and describe the same universe. If that is the case, why would you spend more time teaching and learning the more complex one, when a simple explanation is enough and (by definition, since they have the same predictions) you can't tell which one is correct?

Of course, if the new theory offers a good explanation to current data, but has a different prediction than the standard model in other, still-non-tested scenarios, the theory is more interesting. You can test it at the new scenario, and you'll be able to tell them apart. This is why* we study, for example, supersymmetry and extra dimensions theories: they behave just like the standard model where we have tested it, but can be different in other cases such as the LHC.

* = of course there are other motivations to develop the theories, but they are taken seriously because they are compatible with the SM and are testable. A theory whose predictions were exactly the same as the SM for every case wouldn't be worth studying, simply because you'd never be able to see if it is right.

Re:What if... (1)

Entropius (188861) | more than 4 years ago | (#32413792)

It's that all the bits of the nature of the Universe that we /do/ understand are simple, so we figure that the bits we're still trying to understand are probably also simple.

Re:What if... (4, Insightful)

Hurricane78 (562437) | more than 4 years ago | (#32412734)

No it is not more likely. That’s a common misconception. It is only the one you should pursuit first. Actual facts make things more likely. Not simplicity. Simplification is a artifact injected by humans, because they prefer it for efficiency. (What is commonly calley “laziness”)

Re:What if... (1, Interesting)

Anonymous Coward | more than 4 years ago | (#32412908)

Kolmogorov complexity is defined logically, it is not an "artifact injected by humans", unless you're stating that all mathematics are an "artifact injected by humans".
The poster means that, on the tree of all theories, the ones with the smallest Kolmogorov complexity, are also the one with the highest number of branches, and therefore the ones that are most likely, by the definition of the word "likely".

This doesn't seem to have anything to do with "laziness".

Re:What if... (5, Insightful)

BitterOak (537666) | more than 4 years ago | (#32411828)

That would be pretty amazing as it would violate the Special Theory of Relativity, one of the most tested theories of all time. The problem is, according to Special Relativity, massless particles move at the speed of light, and time does not advance for them. (If you could build a massless clock, its hands would never move.) Oscillations require a time scale. There is a time period of oscillation, or rather the probabilities of being found in a specific state (mu vs. tau, for instance) oscillate with time. Since time stands still for massless particles, this can't happen.

Re:What if... (3, Funny)

Dragoniz3r (992309) | more than 4 years ago | (#32412076)

So that's why fat people live shorter lives! Time really just moves faster for them, because they have more mass!

Re:What if... (2, Funny)

oldhack (1037484) | more than 4 years ago | (#32412514)

All you wise guys think this is funny, but what if it turns out to be true? Huh?!

Re:What if... (1)

KagatoLNX (141673) | more than 4 years ago | (#32412212)

Why couldn't the particle stay the same, but the whole universe oscillates around it?

I actually don't mean to be ironic here. Perhaps they're mathematically the same. IANAPP (I am not a particle physicist). Still, just because something appears to change doesn't mean that it wasn't the observer that changed, right?

Re:What if... (1)

wrf3 (314267) | more than 4 years ago | (#32412462)

Why couldn't the particle stay the same, but the whole universe oscillates around it?

Did Spock come from the future to tell you that you discovered this?

Re:What if... (1)

Steve Max (1235710) | more than 4 years ago | (#32413050)

No, they're not the same. Mass-induced oscillation is a known fact in particle physics (search for "neutron kaon oscillation" for background), and neutrinos behave in exactly the predicted way; only with big mixing angles, unlike the almost-zero angles in the quark sector's CKM matrix.

Re:What if... (2, Interesting)

khayman80 (824400) | more than 4 years ago | (#32412330)

That's the way I've always understood the mass/oscillation connection too. But then I thought... wait... don't photons oscillate too? They're just coherent oscillations of the EM field; oscillating back and forth between electric and transverse magnetic in free space. If there's something different about neutrino oscillation which makes it necessary for the neutrino to travel at sublight, what is it specifically?

Re:What if... (5, Informative)

BitterOak (537666) | more than 4 years ago | (#32412774)

That's the way I've always understood the mass/oscillation connection too. But then I thought... wait... don't photons oscillate too? They're just coherent oscillations of the EM field; oscillating back and forth between electric and transverse magnetic in free space. If there's something different about neutrino oscillation which makes it necessary for the neutrino to travel at sublight, what is it specifically?

The situation you describe with the EM field is an example of wave-particle duality. Light can behave like both a wave and a particle, but it doesn't make sense to analyze it both ways at the same time. As a wave, it does manifest itself as oscillating electric and magnetic fields and as a particle, it manifests itself as a photon, which doesn't change into a different type of particle. (There's no such thing as an "electric photon" and a "magnetic photon".)

Neutrinos, too, are described quantum mechanically by wavefunctions, and these wavefunctions have frequencies associated with them, related to the energy of the particle. But these have nothing to do with the oscillation frequencies described here, in which a neutrino of one flavor (eg. mu) can change into a different flavor (eg. tau). Quantum mechanically speaking, we say the mass eigenstates of the neutrino (states of definite mass) don't coincide with the weak eigenstates (states of definite flavor: i.e. e, mu, or tau). Without mass, there would be no distinct mass eigenstates at all, and so mixing of the weak eigenstates would not occur as the neutrino propagates through free space.

Re:What if... (2, Informative)

khayman80 (824400) | more than 4 years ago | (#32413160)

Thanks. I just found some [uci.edu] equations [ucl.ac.be] that appear to reinforce what you said.

Since the oscillation frequency is proportional to the difference of the squared masses of the mass eigenstates, perhaps it's more accurate to say that neutrino flavor oscillation implies the existence of several mass eigenstates which aren't identical to flavor eigenstates. Since two mass eigenstates would need different eigenvalues in order to be distinguishable, this means at least one mass eigenvalue has to be nonzero. There's probably some sort of "superselection rule" which prevents particles from oscillating between massless and massive eigenstates, so both mass eigenstates have to be non-zero. Cool.

Re:What if... (3, Interesting)

Entropius (188861) | more than 4 years ago | (#32413810)

I don't know of any superselection-rule -- it's possible, in theory, for the electron neutrino to have zero mass but the muon neutrino to have nonzero mass.

But then you'd have to explain why one flavor was massive while the other was massless, which has never happened before. Since there's lots of precedent for three flavors with different nonzero masses, people just figure that the neutrinos are the same way.

Re:What if... (1)

khayman80 (824400) | more than 4 years ago | (#32414056)

I don't know of any superselection-rule -- it's possible, in theory, for the electron neutrino to have zero mass but the muon neutrino to have nonzero mass.

That's fascinating. Do you have a good reference in mind that discusses this topic? I find the idea of a superposition which sometimes travels at lightspeed and sometimes travels slower than light to be... very bizarre.

Re:What if... (3, Interesting)

BitterOak (537666) | more than 4 years ago | (#32414468)

I don't know of any superselection-rule -- it's possible, in theory, for the electron neutrino to have zero mass but the muon neutrino to have nonzero mass.

You can't have oscillations between massless and massive states. Remember, SR says that time stands still for massless particles. If you look at the equations for neutrino oscillations, for example here [wikipedia.org] , you'll see there are expressions involving both the mass squared (for the time evolution of the wavefunction), and mass difference squared, for the mixing amplitudes. So, for quantum mechanical mixing between states, you need both non-zero masses and non-zero mass differences. There may be other, weird mixing theories which don't require mass differences, but they would be quite exotic. On the other hand, mixing of particles with zero masses would violate SR, which would be highly surprising!

Wait a second! Re:What if... (2, Interesting)

eonlabs (921625) | more than 4 years ago | (#32412390)

Does that fact that light is polarizable, has known frequencies of oscillation, and no mass (but has momentum), throw a wrench into all this claim that you need mass to oscillate? Probably not on these forums, but it still makes me pause to think about it.

Re:Wait a second! Re:What if... (4, Informative)

Steve Max (1235710) | more than 4 years ago | (#32413138)

Light doesn't oscillate in this way. A photon is a photon, and remains a photon. Electric and magnetic fields oscillate, but the particle "photon" doesn't. Neutrinos start as one particle (say, as muon-neutrinos) and are detected as a completely different particle (say, as a tau-neutrino).

The explanation for that is that what we call "electron-neutrino", "muon-neutrino" and "tau-neutrino" aren't states with a definite mass; they're a mixture of three neutrino states with definite, different mass (one of those masses can be zero, but at most one). Then, from pure quantum mechanics (and nothing more esoteric than that: pure Schrödinger equation) you see that, if those three defined-mass states have slightly different mass, you will have a probability of creating an electron neutrino and detecting it as a tau neutrino, and every other combination. Those probabilities follow a simple expansion, based on only five parameters (two mass differences and three angles), and depend on the energy of the neutrino and the distance in a very specific way. We can test that dependency, and use very different experiments to measure the five parameters; and everything fits very well. Right now (specially after MINOS saw the energy dependency of the oscillation probability), nobody questions neutrino oscillations. This OPERA result only confirms what we already knew.

Re:Wait a second! Re:What if... (1)

khayman80 (824400) | more than 4 years ago | (#32413298)

The explanation for that is that what we call "electron-neutrino", "muon-neutrino" and "tau-neutrino" aren't states with a definite mass; they're a mixture of three neutrino states with definite, different mass (one of those masses can be zero, but at most one).

Right above I speculated that it's not possible for a particle to oscillate between massive and massless eigenstates. Do you have a reference showing that one mass eigenvalue can be zero? I'm curious to see how a massive particle which travels at v at c is mandatory. I only got through two semesters of quantum using Sakurai in grad school; I'm hoping this point is also comprehensible with the Schrodinger equation and not full QED. (shudder)

Re:Wait a second! Re:What if... (1)

khayman80 (824400) | more than 4 years ago | (#32413318)

Well that got butchered. Change "I'm curious to see how a massive particle which travels at v at c is mandatory." to:

I'm curious to see how a massive particle which must travel slower than light can oscillate into a massive particle that must travel at exactly the speed of light. I'd always figured a superselection rule would prevent this sort of thing...

Re:Wait a second! Re:What if... (1)

Barrinmw (1791848) | more than 4 years ago | (#32413490)

Well, if it went from something with mass to something without mass, could it not use that energy from the mass to speed up to the speed of light? Sort of like how pair production causes light to become two particles traveling slower then the speed of light and then when they annihilate each other you get the photons traveling at the speed of light again?

Re:Wait a second! Re:What if... (2, Interesting)

khayman80 (824400) | more than 4 years ago | (#32414014)

Well, if it went from something with mass to something without mass, could it not use that energy from the mass to speed up to the speed of light?

First, it's one thing to claim that electron-positron collisions produce gamma rays. This is a (generally) non-repeated event with a clear discontinuity in time. Before the discontinuity, particles travel slower than light. Afterwards, the products of the collision travel at lightspeed. But an oscillating particle varies smoothly and repeatedly between the two states so there's no clear discontinuity even though the physics of massless and massive particles are wildly different.

Second, I'm not suggesting such a superposition would violate conservation of energy. I'm struggling to put my objections in words. First, I grok quantum superpositions of electrons in different places or polarizations. But I don't think it's possible to have a quantum superposition of an electron and a proton because that would violate conservation of charge, mass, lepton number, and baryon number. (I believe this general idea is known as a superselection rule, which forbids certain superpositions.) In the same way, I'm trying to figure out if a superposition of a particle that defines the light cone and a particle that's constrained to move inside the light cone is meaningful. No conservation laws seem to apply, but I'm vaguely thinking that environmentally-induced superselection wouldn't allow such a superposition to exist for much longer than a Planck time.

Sort of like how pair production causes light to become two particles traveling slower then the speed of light and then when they annihilate each other you get the photons traveling at the speed of light again?

A photon can only produce a real electron-positron pair when it has at least twice the rest-energy of an electron and it hits a nucleus. Photons can't produce real particle pairs in free space because momentum and energy can't be simultaneously conserved without a third particle.

The fact that light travels slower in matter can be explained in many different ways. Some QED cartoons attribute this to the effective non-zero mass of a quasi-particle known as a polariton [wikipedia.org] , which is composed of a photon and phonons in the material. Again, this doesn't happen in free space. Also, this example involves virtual particles but the oscillating neutrino is real (because it can be detected as a single particle.)

Re:What if... (1)

Burz (138833) | more than 4 years ago | (#32413600)

The problem is, according to Special Relativity, massless particles move at the speed of light, and time does not advance for them.

But can't photons be generated and absorbed? Wouldn't that be a change in state over time? How about Doppler shifting.. doesn't that indicate the frequency and energy level of a photon can change over time?

Maybe massless particles can change over time if they are being changed by some (unknown) property of spacetime.

Excited! (5, Insightful)

SpeedyDX (1014595) | more than 4 years ago | (#32411462)

Reading TFS made me very excited about the potential fundamental developments in physics. Except I don't know a thing about physics, so I'm really not sure what I'm excited about. All these words like muon, tau, and neutrino have little place in my everyday life, but they sound so interesting!

This is what the Average American must feel like when they hear stories about Web x.0 laden with the latest buzzwords on CNN. I can finally relate!

Re:Excited! (0)

Anonymous Coward | more than 4 years ago | (#32411592)

I agree... we need some Slashdotter to come up with a car analogy to help us non-physicists out.

Re:Excited! (4, Insightful)

biryokumaru (822262) | more than 4 years ago | (#32412006)

Imagine your definition of sports cars (massless particles, thus no time) didn't include convertibles (time-based oscillation). For a car to be convertible, it has to be a luxury car (have mass), not a sports car. Then, you see a sports car drive by a few times, and one of the times the top is down. You have to wonder, is it not really a sports car (the way we think neutrinos work must change), or is your definition of sports cars broken (the way we think mass works must change)?

How's that sound?

Re:Excited! (3, Funny)

oldhack (1037484) | more than 4 years ago | (#32412532)

Depends. Are they German or Japanese?

Re:Excited! (5, Interesting)

$RANDOMLUSER (804576) | more than 4 years ago | (#32412480)

...we need some Slashdotter to come up with a car analogy to help us non-physicists out.

Glad to oblige.

Imagine a highway. All the north-bound cars are WHITE Toyota Camrys, and all the south-bound cars are BLACK Toyota Camrys. All the cars are moving very very very fast. At a certain point in the road, workers open gates that cause the two streams of traffic to plow into each other, head on. At the crash site, common sense would tell you that pieces of Toyota Camrys would come flying out, but instead, complete vehicles of other makes and models (Honda Civics and Nissan Sentras, many others, including vehicles larger than two Camrys, like Peterbilt 18-wheelers) appear instead. After a few seconds, some of these vehicles break apart, and become other vehicles, say a Peterbilt breaks apart and becomes a Ford F-150 and two Harley Davidson motorcycles. Particle physicists make a living by crashing different streams of vehicles into each other and observing the new vehicles that come out. They've put together a list of these, like "Peterbuilt --> Ford F-150 + 2(Harley Davidson Motorcycles)". They call this list the Standard Model. This new experiment shows that sometimes, after a while, one of the Harleys suddenly changes models, say from a Fat Boy to an Electra Glide.

Hope this helps.

Re:Excited! (0)

Anonymous Coward | more than 4 years ago | (#32411610)

Indeed, the only thing I could refer to was "Opera", but I don't think they're talking about the Web Browser...

Re:Excited! (1)

darkmeridian (119044) | more than 4 years ago | (#32413748)

The significance of this discovery is that the Standard Model is wrong. The transformation of neutrinos mean they have mass, whereas the Standard Model predicts that they have no mass. Neutrinos having mass mean they interact with matter, and that they can constitute dark matter. Or something like that. This is about all I know/or think I know about the subject.

I hope I'm alive when the Next Big Nerd figures out the Next Big Thing regarding a Theory of Everything.

Re:Excited! (1)

Entropius (188861) | more than 4 years ago | (#32413864)

How exactly does the standard model demand that neutrinos have mass?

The SM works just fine with massive neutrinos. After all, most of the fun stuff in the SM concerns the gauge couplings; whether or not a few fermions have mass doesn't affect the overall theory.

Neutrinos could constitute dark matter if they had *more* mass. But we can put an upper limit on the masses of the electron, muon, and tau neutrinos, and that's not enough to account for the amount of dark matter we know is out there. Some sort of exotic thing -- sterile neutrino flavors or some SUSY mumbo-jumbo -- /could/ be a dark matter candidate.

Chameleon-Like Behavior? (5, Funny)

Randle_Revar (229304) | more than 4 years ago | (#32411506)

I don't see how changing from one thing into another is "chameleon-like behavior". I have never heard of a chameleon turning into a skink, or anything else for that matter

Re:Chameleon-Like Behavior? (0)

Anonymous Coward | more than 4 years ago | (#32411590)

The changes might be likened to a red photon suddenly turning into a blue photon. Apparently energy is being exchanged in a yet to be discovered manner. Or, perhaps the observed changes indicate that the Neutrinos simply came out of the closet.

Re:Chameleon-Like Behavior? (1)

Steve Max (1235710) | more than 4 years ago | (#32411698)

No, it may not. The neutrino's energy (which is the exact analog to a photon's "colour") is conserved. The rest energy changes, but this means the original neutrino and the resulting one are on different rest referentials (and the change in mass is very small, inside the uncertainty principle). There is nothing "yet to be discovered", except possibly what is the mass generation mechanism (Dirac, like all other particles, or Marjorana).
"Chameleon-like behaviour" is just the "scientific" journalist's way of saying he understands nothing about what he is paid to write; but we all know journalists rarely know much of what they write anyway.

Re:Chameleon-Like Behavior? (3, Informative)

dumuzi (1497471) | more than 4 years ago | (#32411680)

I agree. In QCD quarks and gluons can undergo colour changes [wikipedia.org] , this would be "chameleon-like behavior". Neutrinos on the other hand change flavour [wikipedia.org] , this would be "Willy Wonka like behavior".

Re:Chameleon-Like Behavior? (2, Funny)

biryokumaru (822262) | more than 4 years ago | (#32412008)

You could say they're acting wonky.

Re:Chameleon-Like Behavior? (1)

Jorl17 (1716772) | more than 4 years ago | (#32411812)

I'm sure you'd prefer the non-falacious "chamaleon-skin-color-like behaviour". Though that might not fit it either.

Re:Chameleon-Like Behavior? (1)

buchner.johannes (1139593) | more than 4 years ago | (#32411904)

I don't see how changing from one thing into another is "chameleon-like behavior". I have never heard of a chameleon turning into a skink, or anything else for that matter

Try combining a chameleon with a hammer or a microwave. Then you will understand the experiments analogy.

Re:Chameleon-Like Behavior? (0)

Anonymous Coward | more than 4 years ago | (#32411944)

I don't see how changing from one thing into another is "chameleon-like behavior". I have never heard of a chameleon turning into a skink, or anything else for that matter

Try combining a chameleon with a hammer or a microwave. Then you will understand the experiments analogy.

Splattered lizard guts?

Re:Chameleon-Like Behavior? (1)

jnnnnn (1079877) | more than 4 years ago | (#32412032)

One of the properties of subatomic particles is referred to as colour. The particles are not coloured (they are far smaller than the wavelengths of light that give colour), but it is a simple system of classifying particles, similar to resistor colour codes or the "terrorist" alert system.

The study of the colour properties is called "chromodynamics", and I guess "chameleon" must be a similar extension of the metaphor.

Re:Chameleon-Like Behavior? (1)

mog007 (677810) | more than 4 years ago | (#32413344)

Neutrinos do not see the strong force, which is where the color charge comes from. Neutrinos interact with the weak force, and gravity. They have no color charge, and no electric charge, so they are basically dumb to the idea of the strong and electromagnetic forces.

Re:Chameleon-Like Behavior? (0)

Anonymous Coward | more than 4 years ago | (#32412860)

My entire house is made out of chameleons you insensitive clod!

Re:Chameleon-Like Behavior? (0)

Anonymous Coward | more than 4 years ago | (#32413942)

No but they can turn into dinner :D

Neutrinos acting like Microwaves (1)

snowgirl (978879) | more than 4 years ago | (#32411518)

Just find the people from the Movie 2012 to help you figure out how to make the Neutrinos act like Microwaves, then you could totally make this experiment easy! ... seriously... did anyone else need a friend to "dumb up" the science dialog for them?

Re:Neutrinos acting like Microwaves (0)

Anonymous Coward | more than 4 years ago | (#32411848)

Easy there, snowgirl. It's just a movie, designed for entertainment purposes only. It's not a scientific documentary nor was it meant to be. Sit back and just enjoy the show :)

Re:Neutrinos acting like Microwaves (0)

Anonymous Coward | more than 4 years ago | (#32411878)

I needed quite a few pauses on that movie to laugh at its science dialog. I can't imagine it being any more wrong. Solar neutrinos (very low energy) heating up the Earth's core? "The first time neutrinos have a physical reaction"? Really? Was their science advisor a magic 8-ball?

Re:Neutrinos acting like Microwaves (1)

snowgirl (978879) | more than 4 years ago | (#32411978)

Was their science advisor a magic 8-ball?

My sources say no.

Re:Neutrinos acting like Microwaves (1)

biryokumaru (822262) | more than 4 years ago | (#32412028)

Signs point to yes.

Re:Neutrinos acting like Microwaves (1)

Mr. Underbridge (666784) | more than 4 years ago | (#32413900)

Just find the people from the Movie 2012 to help you figure out how to make the Neutrinos act like Microwaves, then you could totally make this experiment easy! ... seriously... did anyone else need a friend to "dumb up" the science dialog for them?

I had the pleasure of (involuntarily) watching that piece of shit this weekend. Sadly, the liberties taken with science were the least of that movie's problems. I'd start with the terrible script, lack of editing (solid hour too long), screwed up pacing, repetitive scenes, 70s-grade CGI, and heavy handed moralizing. Compared to that, they could have said that neutrinos turn into faerie dust and I'd have been fine.

Re:Neutrinos acting like Microwaves (1)

snowgirl (978879) | more than 4 years ago | (#32414228)

Compared to that, they could have said that neutrinos turn into faerie dust and I'd have been fine.

This I at least could have understood.

None of their scientific babbling made any sense to me until my friend's boyfriend explained what the heck they were trying to say.

Fir5t (-1, Offtopic)

Anonymous Coward | more than 4 years ago | (#32411532)

good Manners but it's not a

oscillation (2, Interesting)

Spazmania (174582) | more than 4 years ago | (#32411544)

The Standard Model of fundamental particles posits no mass for the neutrino. For them to be able to oscillate, however, they must have mass.

Unless oscillation is the fundamental thing and mass is just a sometimes effect of oscillation... but then IANAP.

Re:oscillation (1)

Dragoniz3r (992309) | more than 4 years ago | (#32412114)

Doesn't matter what we call the two things. We just know that in this case, one requires the other.

They explained this on NOVA a while ago (1)

NotSoHeavyD3 (1400425) | more than 4 years ago | (#32412306)

Basically oscillations are repeated changes with respect to time. According to general relativity massless particles move at light speed and as a consequence do not experience the passage of time. So if neutrino's were massless they'd move at light speed and wouldn't experience time and therefore wouldn't be able to oscillate into different forms.

Re:They explained this on NOVA a while ago (1)

Spazmania (174582) | more than 4 years ago | (#32412944)

Alas my humor remains too subtle...

How in the universe? (3, Interesting)

MyLongNickName (822545) | more than 4 years ago | (#32411554)

How could something have mass and so weakly interact with normal matter? My understanding is that most neutrinos pass through the earth unmolested.

(insert obligatory Catholic priest joke here).

I's thought that neutrinos being massless made this possible.

Re:How in the universe? (0)

Anonymous Coward | more than 4 years ago | (#32411624)

Think about it this way.. how can something not have mass?

Re:How in the universe? (5, Funny)

rogeriomgatto (1364629) | more than 4 years ago | (#32411686)

That's how they managed to escape the priests... They avoid mass.

Re:How in the universe? (4, Informative)

pz (113803) | more than 4 years ago | (#32411738)

How could something have mass and so weakly interact with normal matter?

Neutrinos are thought to have a very small mass. So exceedingly small that they barely interact with anything (they also have no charge, so they are even less likely to interact). But zero mass and really, really, really small but not zero mass, are two different things.

Re:How in the universe? (5, Informative)

BitterOak (537666) | more than 4 years ago | (#32411982)

How could something have mass and so weakly interact with normal matter?

Neutrinos are thought to have a very small mass. So exceedingly small that they barely interact with anything (they also have no charge, so they are even less likely to interact).

The fact that they barely interact with anything has nothing to do with the fact that they are nearly massless. Photons are massless and they interact with anything that carries an electric charge. Electrons are much lighter than muons, but they are just as likely to interact with something. The only force that gets weaker as the mass goes down is gravity, which is by far the weakest of the fundamental forces.

Re:How in the universe? (1, Interesting)

Nimey (114278) | more than 4 years ago | (#32412748)

Photons also interact with gravity - stellar masses and above can cause gravitational lensing.

Re:How in the universe? (1)

Barrinmw (1791848) | more than 4 years ago | (#32413518)

And then you can maybe get Weakly-Interacting Massive Particles that can interact with just the Weak Force and Gravity.

Re:How in the universe? (1, Interesting)

Anonymous Coward | more than 4 years ago | (#32413968)

I thought that phenomenon was caused by the curvature in space-time, so IMHO it wasn't "interaction" per-se.

Re:How in the universe? (1)

pz (113803) | more than 4 years ago | (#32413094)

The fact that they barely interact with anything has nothing to do with the fact that they are nearly massless. Photons are massless and they interact with anything that carries an electric charge. Electrons are much lighter than muons, but they are just as likely to interact with something. The only force that gets weaker as the mass goes down is gravity, which is by far the weakest of the fundamental forces.

Good point, I should have been more expansive. There are definitely many more reasons that neutrinos are non-interactive.

Re:How in the universe? (1)

justin12345 (846440) | more than 4 years ago | (#32413700)

I once read somewhere that the fundamental difference between something with mass and something without mass is that "at rest" (a purely theoretical state) an object with mass it would be stationary (that is to say absolute zero motion and temperature). An object without mass "at rest" would move at the speed of light. It would take an infinite amount of energy to accelerate an object with mass to the speed of light, and an infinite amount of energy to decelerate an object without mass to absolute zero.

I have no idea if there is any validity to this, and I can't recall where I read it, but I've always thought it was an interesting thing to think about. Perhaps someone can correct me or fill in the blanks.

How measure no charge, no mass? (1)

LongearedBat (1665481) | more than 4 years ago | (#32414384)

Okay, so neutrinos have a tiny mass. But if a particle has actually no mass and no charge, how could one find out that it even exists? (Just curious.)

Re:How measure no charge, no mass? (1, Informative)

Anonymous Coward | more than 4 years ago | (#32414422)

Photons are masless and chargeless, right?

Re:How in the universe? (0)

Anonymous Coward | more than 4 years ago | (#32411764)

No pudding for you. How could they have some pudding if they don't eat their mass :)

Re:How in the universe? (5, Interesting)

hoytak (1148181) | more than 4 years ago | (#32411824)

Neutrinos only interact through the weak forces, which require them to be extremely close to other particles with which they interact. Such interactions also require the neutrino to have a lot of energy, since the force-carrying particles are quite massive. This is why all these experiments use neutrinos generated by very energetic reactions (accelerators, the sun, cosmic rays, etc.).

When I worked with BooNE, an experiment researching neutrino osculations, our detector was a 40 ft tank lined filled with clear, food-grade mineral oil and lined with photo tubes capable of detecting a few photons. The neutrinos were generated by bursts of protons crashing into a special block (I don't remember the material), and the byproducts at the given energy levels would be one type of neutrino. The interactions from different types of neutrinos would have different decays, which produced different signature rings of photons on the walls of the detector. In generating 10^9 + neutrinos, we only expected a handful of interactions.

Gravity is also on the table, but it's impossible to measure neutrinos based on that.

Re:How in the universe? (1)

Barrinmw (1791848) | more than 4 years ago | (#32413534)

Hey, my fiancee's father just got picked up to work on BooNe. Small world.

Re:How in the universe? (1)

Sulphur (1548251) | more than 4 years ago | (#32414482)

If a neutrino tunnels out of a black hole, does it radiate Hawkings?

Re:How in the universe? (1)

dimeglio (456244) | more than 4 years ago | (#32411840)

Photons are also massless and also interact with matter. Photons/electrons are also waves/particles which make them rather interesting. There might be different types of neutrinos. Some with mass, other with none. Since neutrinos are the results of a proton collision, the opposite - recreating a proton with a neutrino/strange quark collision might also explain this "mass-like" behaviour. Interesting nonetheless.

Re:How in the universe? (1)

BitterOak (537666) | more than 4 years ago | (#32411852)

How could something have mass and so weakly interact with normal matter? My understanding is that most neutrinos pass through the earth unmolested.

(insert obligatory Catholic priest joke here).

I's thought that neutrinos being massless made this possible.

I'm not sure why this was modded flamebait (is a reference to our propensity to joke about the Catholic church flamebait?), but to answer the question, being massless has nothing to do with a particle's ability to interact weakly. Quarks can interact weakly (as well as strongly and electromagnetically) and they certainly have mass. The top quark, in fact, is quite heavy.

Re:How in the universe? (0)

Anonymous Coward | more than 4 years ago | (#32411992)

(insert obligatory Catholic priest joke here).
I's thought that neutrinos being assless made this possible.

Catholic priests wouldn't be able to bugger the neutrinos if the neutrinos were assless, but that's okay -- there are more than enough altar boys and Hatian orphans to go around.

Re:How in the universe? (5, Interesting)

Snowhare (263311) | more than 4 years ago | (#32411998)

It isn't their mass that makes them so unlikely to interact with ordinary matter. It is because they don't interact via the Electromagnetic or Strong Nuclear forces (at least not at the energies we are discussing here). Because we can't use gravity to directly detect them (or any other elementary particle) because of its incredible weakness, that leaves only the Weak Nuclear force, which is *extremely* short range. That short range means that a neutrino must pass *very* close to an electron or a quark to have any chance what-so-ever of interacting: Something like 10 to the minus 16th power meters. For comparison, a hydrogen atom has a diameter of around 10 to the minus 10th meters - or a million times larger.

A single *proton* has a diameter of around 10 to the minus 15th meters - or still 10 times larger than the distance in question.

So hundreds of neutrinos could pass directly through the very nucleus of an atom and *still* not interact with anything. And that is matter with a density more than a trillion times as dense as anything in your ordinary experience.

To neutrinos, other matter barely exists at all.

Re:How in the universe? (0)

Anonymous Coward | more than 4 years ago | (#32413370)

I's thought

What is that supposed to be in proper english?

Douglas Adams was right (1)

Fractal Dice (696349) | more than 4 years ago | (#32411810)

We finally understood the universe, so it has been replaced with something even more perplexing.

Re:Douglas Adams was right (1)

vjoel (945280) | more than 4 years ago | (#32412002)

We finally understood the universe, so it has been replaced with something even more perplexing.

This already happened long ago....

Shifty characters... (1)

WeatherGod (1726770) | more than 4 years ago | (#32412012)

I knew I couldn't trust 'em!

I thought -I- was a nerd.... (0)

Anonymous Coward | more than 4 years ago | (#32412206)

>> the first direct observation of a muon neutrino turning into a tau neutrino

Please forgive me in advance for asking, but why is this important?

I now know how people feel when I respond to their questions regarding computers, networks, etc.

Re:I thought -I- was a nerd.... (2, Insightful)

oldhack (1037484) | more than 4 years ago | (#32412396)

We've been observing only a third of neutrinos from the sun, and the speculation was that the rest were oscilliating into others not being detected, and that would be possible if neutrinos had mass, and that means one or the other symmetries in the standard model needs to be tweaked, and so on.

Get it? No, I don't get it either, but I'm no physicists.

karma neutrino (0)

Anonymous Coward | more than 4 years ago | (#32412374)

Karma karma karma karma karma neutriiiino!

Robust result? (2, Insightful)

harryjohnston (1118069) | more than 4 years ago | (#32413454)

Offhand, this doesn't seem like a very robust result - we're only talking about a single observation, after all. Does the equipment allow them to determine the source of the observed tau neutrino? How can they be sure that it came from the muon neutrino stream from CERN rather than being random background?

There's also no mention of a control, e.g., another tau neutrino detector close to the same muon neutrino source. Even if there was, is a single detection versus no detections statistically significant?

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