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OPERA Group Repeats Faster-Than-Light Neutrino Results
gbrumfiel writes "Earlier this year, the OPERA experiment made the extraordinary claim that they had seen neutrinos traveling faster than the speed of light. The experiment, located at Gran Sasso in Italy, saw neutrinos arrive 60 nanoseconds earlier than expected from their starting point at CERN in Switzerland. Others have doubted OPERA's claim, but in a new paper, the group reaffirms its commitment to the measurement. 'It's slightly better than the previous result,' OPERA's physics coordinator Dario Autiero told Nature News. Most members of the collaboration who didn't sign the original paper out of skepticism have now come on board. But scientists outside the group still aren't sure. 'Independent checks are the way to go,' says Rob Plunkett, co-spokesman of a rival experiment called MINOS."
Not in a supernova burst. The initial implosion is deep inside the neutron star, and there's a lot of matter shielding it. Light interacts with matter, so it gets delayed on its way out, but the neutrino burst from that initial implosion doesn't. The predicted delay was of the same order of magnitude as the delay seen in SN1987a.
The Bible does not list an age for the Universe, nor even for planet Earth.
Or maybe some as-yet-undiscovered property of spacetime or the universe at the quantum level delays neutrinos over vast distances...
Unfortunately for us, replicating the experiment with a second team in a second location entirely from scratch will be extremely expensive, given that this CERN location used for the experiment is unique.
Do not look into laser with remaining eye.
The new measurement is much more convincing than the previous one. The difference is the size of the proton bunches used to produce the neutrinos at CERN: in original measurement, the proton bunches where huge (milliseconds) compared to the claimed offset in the neutrino pulse (60 nanoseconds). This required a lot of knowledge about the shape of the proton bunches, and a lot of statistical fitting. The new analysis includes a special run with nanosecond-width proton bunches, widely separated from one another, so that each neutrino can be definitely associated with a particular proton bunch at CERN, with knowledge of the production time at the nanosecond level.
Personally, I'll still be skeptical until it's confirmed by an independent group, but the result is a lot more believable now.
Unfortunately for us, replicating the experiment with a second team in a second location entirely from scratch will be extremely expensive, given that this CERN location used for the experiment is unique.
There are other long-baseline neutrino experiments out there, such as MINOS.
Simply put, the neutrino emission starts before the emission of light. This article has details: http://library.lanl.gov/cgi-bin/getfile?25-14.pdf
This is addressed in the paper. The 1987a neutrinos have energies in the 1-20 MeV range while the OPERA result is for neutrinos in the 3-100 GeV range. That is around three orders of magnitude higher than the 1987a result. Page 3 section 1 paragraph 3 covers this (for some reason Slashdot won't let me block quote it):
http://arxiv.org/pdf/1109.4897v2
Superluminal neutrinos must have energy dependent velocities.
Ummm, no? They didn't just use GPS clocks, they physically carried atomic clocks from one location to the other. Look up the actual science behind what they did, it's pretty interesting. Oh, and relativistic factors of GPS systems is pretty standard learning in basic science. Maybe there was a compounding effect that they missed... but I doubt it. That article is 100% pure speculation. And it's bullshit, quite frankly. Check out this: Ars article for what the team did. (They also ran photons between the sites to check the time, in addition to GPS and portable atomic clocks.)
"None can love freedom heartily, but good men; the rest love not freedom, but license." --John Milton
I'm not an expert on theoretical physics but according to the Standrad Model, neutrinos were originally thought to be mass-less. But the in trying to detect solar neutrinos, Raymond Davis could only detect 1/3 of the neutrinos predicted by the Standard Model. This lead to a puzzle known as the solar neutrino problem as no one could find a fault with his experiments but they couldn't explain his curious results either. It wasn't until Masatoshi Koshiba verified the same effect in a different experiment that scientists began to believe his results. The problem was the Standard Model was wrong. Neutrinos because they were massless should also be stateless. Subsequent experiments showed that solar neutrinos were not stateless as they oscillate into different types of neutrinos. Thus they could not be massless. Davis and Koshiba shared part of the 2002 Nobel Prize for this discovery.
Well, there's spam egg sausage and spam, that's not got much spam in it.
Uh, just to be specific, you're talking about the chirality of neutrinos. The way you phrase it, it sounds like an electron is a type of neutrino. It isn't. There are electron neutrinos, but they have no charge. They are merely part of the same family of leptons as the electron, hence the name. You probably knew that, but I had to do a re-read to figure out that that's not necessarily what you meant.
Those who can, do. Those who can't, sue.