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A Fermilab First: Detecting Oscillating Neutrinos
An announcement at last week's American Physical Society's Division of Particles and Fields conference revealed that Fermilab's NOvA experiment has for the first time observed oscillating neutrinos, which have long been predicted but -- as a case even more special than observing neutrinos in general, not an easy task -- never before detected. The research team fired
trillions of of muon neutrinos from an accelerator at the Fermilab, outside Chicago. The neutrinos travel 500 miles through Earth's crust to a detector at Ash River, Minnesota. There, scientists were able to filter through millions of cosmic ray strikes and hone in on neutrino interactions. The arriving neutrinos featured some electron neutrinos, suggesting they had oscillated along their path through Earth. "Basically, it shows that we know what we're doing," said Patricia Vahle, associate professor of physics at the College of William & Mary.
Neat.
Thanks for posting
Actually, oscillating neutrinos have been detected before. They just were from the sun, not human made. https://en.wikipedia.org/wiki/...
In what way(s) is this experiment different from https://en.wikipedia.org/wiki/...
?
It's not C
The poster has misread the announcement and failed to check his facts. It is the first recorded detection of neutrino oscillation by the equipment of FNAL, not the first detection at all.
Everytime I read such an article, I think that sales people are on it.
There's a headline in my country reading "X university discovers Z!" And the bylines are: "U and V are also involved"
(X is an uni in my country....)
When I read it in another country "U discovered Z!" Bylines "X and V also helped!"
etc..
Ugh!
Some theorists have been ridiculed for pointing out the over-confidence in this claim.
Can those neutrino oscillations be modulated at will so as to transfer data? Just imagine being the guy with the neutrino path through the Earth's crust beating all those other HFT guys to the femtosecond.
"Everybody's naked underneath" -- The Doctor
Okay, headline and summary are just plain wrong. Neutrino oscillations of nearly all kinds have been observed in countless experiments around the world. This includes man-made neutrinos from accelerators (one example is the famous Opera experiment, which is better known for its false measurement of superluminous neutrino speeds).
So I really don't understand what the big deal is. I mean, it's nice that NOvA could *also* confirm that neutrinos oscillate, but that's hardly worth a message. Every few months some new experiment measures neutrinos and you can't hear them brag about it...
"Basically, it shows that we know what we're doing,"
Defensive and usually false.
"Why is there stuff? Matter and antimatter could have just annihilated and we'd be left with nothing in the universe but energy. If the answer isn't in neutrinos, it's something really exotic."
We have basically 2 things, + and -, you don't have matter and anti-matter, both particles have +ve mass, an anti-electron is simply an electron with opposing charge but the same mass. The difference is the charge. If there are two fundamental particles under all of these neutrinos, and quarks and even photons, then there will be 2 of them. One positive and one negative.
And any stable configuration you can make of these + and - particles, you could swap the + and - and mass an equally stable config. So any particle you can make that has a stable outer -ve effect (like an electron), you can swap all the pluses and minuses and make the anti-particle (a positron).
So all charged particles must also be dipolar, so you must be able to detect a dipole effect in an electron for example [yes].
So you'll always find an anti-particle for every particle. Even ones that are neutral have corresponding neutral configurations. Since the difference is the charge, it follows that there would be two fundamental particles!
What would happen if an electron and positron collided? You'd end up with a cloud of +- spinning around each other surely? But you get a photon right pure energy no mass? So what is a photon? And what is the proof that a photon isn't a cloud of these small dipoles?
such a cloud would have momentum [check], magnetic fields [check], go through both slits of a double slit experiment despite being a single photon [check], behave in a probablistic manner [check].
It doesn't have to be exotic, you just have to re-examine the QM model, its broken.
Man I'd hate to be someone in the middle of that path without knowing it, perhaps where a fault or something ejects lots of these neutrinos upward through some guys bedroom where he sits idle for hours absorbing them.....
Now he's just been bombarded for days on end and starts developing weird symptoms without a clue why.
Seems like this should be regulated.
Actually the summary is wrong. Neutrino oscillations have been detected before from atmospheric neutrinos, solar neutrinos and beam neutrinos (e.g. the T2K experiment). The linked article technically gets it right, but is somewhat misleading, calling it "our first observation" where 'our' refers to the Nova experiment and not humanity in general i.e. it is the first time that the Nova experiment has detected oscillating neutrinos.
This is an important milestone for them but just indicates that their detector works in much the same way that we measured known Standard Model processes at the LHC before going after the higgs boson. If you can't see the physics that we know is there first nobody will believe you if you claim to see something new. Hopefully this is just the precursor for some interesting results from Nova...and hopefully they can get the Fermilab PR machine to write less misleading/hyped press releases when they do have some exciting results to announce!
Can those neutrino oscillations be modulated at will so as to transfer data?
Technically yes they could. When neutrinos pass through matter the electron-neutrino part of them interacts differently to the muon and tau parts because matter contains electrons (something called the MSW effect). However because at typical energies neutrinos interact only very weakly with matter the effect is very tiny and so far is only significant when neutrinos pass though objects like the Earth or the Sun. This means that you would need an extraordinarily sensitive detector, very high energy neutrinos [at energies 1000+ times greater than the LHC neutrinos start to interact a lot more readily with matter] and/or an incredibly intense neutrino beam.
A better way to modulate the neutrino beam would be to change the way it is generated assuming it is created from an accelerator. By altering the polarity of the magnets selecting the muons which then decay you could flip the beam back and forth between muon neutrino and anti-neutrino. This would not be a fast process though and you still need an extremely large detector (thousands of tons or more) to detect them and then there is stil the issue of analysis to get the signal. This makes it impractical for HFT applications although if it could be made to work you'd actually beat the competition by a lot more than a femtosecond: the gain is up to 45 milliseconds if you were transmitting straight through the centre of the Earth.
So far this is in line with previous observations and neutrino models... and the goal is to improve on previous measurements to get better error bars on things like neutrino mixing angles.
So what are you opposing exactly, that when measurements are improved or find something new, people incorporate that into new work? Should we instead just ignoring new data, or not trying to make predictions to know where to look, or just not look at all?
Actually, oscillating neutrinos have been detected before. They just were from the sun, not human made.
https://en.wikipedia.org/wiki/...
Yes, I was wondering about that--I remember a physics prof saying that all particles oscillated at an integer multiple of Planck's constant, and I knew we'd detected neutrinos before.
IIRC it's how we detect a supernova before we see the fireball--the neutrinos are so small and move so fast that they make it out of the core of the exploding star a short time before the star actually explodes, giving us a chance to train an instrument or two on the star.
Astrophysicists in the room, feel free to correct me.
It positions itself as a C/C++ killer but benchmarks closer to Java in performance. Like other languages that try to be a better C/C++, it has a steep road ahead. Time will tell this one, not slashdot users. If making a C/C++ replacement was all it takes, D would have taken off.
So far this is in line with previous observations and neutrino models... and the goal is to improve on previous measurements to get better error bars on things like neutrino mixing angles.
So what are you opposing exactly, that when measurements are improved or find something new, people incorporate that into new work? Should we instead just ignoring new data, or not trying to make predictions to know where to look, or just not look at all?
You managed to read quite a lot from one line there.
Still love this one. Bar tender looks up and says "Hey we don't serve faster than light neutrinos here!" A neutrino walks into a bar.