Posted on 06/08/2012 8:33:17 PM PDT by presidio9
Eight months after the multinational Opera research team caused an uproar among physicists with its findings that some neutrinos appeared to travel faster than light, its findings have been officially refuted.
CERN, the European Organization for Nuclear Research, on Friday said that four experiments have found that neutrinos actually travel no faster than the speed of light.
Opera's original measurements can be attributed to a faulty element of its experiment's fiber optic timing system, CERN said.
The findings were announced at the 25th International Conference on Neutrino Physics and Astrophysics in Kyoto, Japan, by CERN research director Sergio Bertolucci.
Life in the Fast Neutrino Lane
Opera's initial findings, announced in September, triggered skepticism among the scientific community because, if validated, they could have meant that Einstein's theory of special relativity was wrong. Special relativity will only hold true when space-time is flat, and if the theory is wrong, it could mean that the curvature of space is hidden somehow.
Another possibility suggested by faster-than-light neutrinos was that special relativity doesn't apply to neutrinos. That would have impacted quantum theory because it's based on the balance between quantum behavior and special relativity.
A neutrino is an electrically neutral elementary subatomic particle with a small mass that usually travels close to the speed of light.
The Opera Experiment
The Opera team shot a high-intensity, high-energy beam of muon neutrinos produced at the CERN SPS accelerator in Geneva at the LNGS underground laboratory at Gran Sasso in Italy, 730 km (454 miles) away and measured the speed at which the neutrinos emitted traveled.
Preparations for the experiment were apparently meticulous. The Opera team worked with experts in metrology, or the science of measurement, from CERN and other institutions to measure the distance between CERN SPS and LNGS with an uncertainty of 20 cm (7.9 inches) over 730 km. Advanced GPS systems, atomic clocks and other sophisticated instruments were used to ensure the scientists could measure the neutrinos' time of flight to within less than 10 nanoseconds of accuracy.
The neutrinos' velocity was determined using high-statistics data collated by the Opera neutrino detector at LNGS from 2009. This detector consists of two identical Super Modules, each being an instrumented target section with a mass of about 625 tons followed by a magnetic muon spectrometer.
It took the neutrinos about three milliseconds to travel the 730 km. This is a measure of the time distribution of protons each time the beam was fired, aggregated and normalized. It's not possible to precisely measure the time of flight of any single neutrino because any proton might produce the neutrino detected by the Opera detector.
E=MC2, Dammit!
Four teams conducted experiments at Gran Sasso in May to check Opera's findings. They are Opera, Borexino, Icarus, and LVD.
Borexino, Icarus, Japan's T2K experiment and the United States' Minos experiment were originally slated to conduct the cross-checks, and it's unclear why the lineup was changed.
"Each experiment necessarily has its own timing system to record the time of its events," Michael Witherell, vice chancellor for research at the University of California Santa Barbara's physics department, told TechNewsWorld.
Opera's discovery of problems with its timing system was announced on Feb. 23, Witherell said. "At that time, CERN said that Opera would have their first neutrino run with the repaired timing system in May. Apparently, all four experiments ran in that May run, and all say transit times were consistent with the speed of light."
Into the Sun
In October,
I use French Vanilla creamer in my tea ... I like cream tea.
If the Universe is made of empty space, and expanding, what do we call the part the Universe is expanding into?
And how big is it?
Wow. I don't have any answer to that.
IF you were in a spaceship, way out in interstellar space, how would you know how fast you were going?
What immovable point would you measure from?
If you left the Earth at , say, 100,000mph and exited our galaxy, would you still be going 100,000 mph?
(oops) I meant to quote your comment from post 40.
It must be late. Or, I’ve gone past the edge of the known universe.
(shrug) There must be, or there wouldn't be any energy. Because, after all, energy is equal to mass times the speed of light squared.
Gravity or links between entangled particles, to name a few, are other “things” to consider, that may/do travel faster than C; but then these “things”, among others, are likely neither E nor M. :)
“Did he ever consider that the speed of light was not an historical constant?”
Actually that is the exact exit that he chose
TT
The only question I have, is there some massless particle (or a particle with a negative mass) that can travel faster than the speed of light?
The math of relativity tells us that in order to move faster than C you must have an imaginary (square root of -1) rest mass, whatever that means.
The sad thing is, if you recognize the group in the photo, you’re an old man. If they just look like a bunch of hippies to you, you’re a REALLY old man.
There are ways around everything.
“Cut to the chase. Does this mean humans will never get star travel?”
We’ll get there. We just don’t understand even the basic concepts yet.
In the most recent Star Trek movie, the elder Spock showed the younger Scotty the equation to achieve transport through hyperspace. Scotty took one look at the numbers and said, “Huh, I didn’t realize that space was the thing moving.” That’s science fiction, but it does illustrate one point: Our ideas of physics are vastly limited.
One hundred years ago the Sopwith Camel biplane was still a few years away. Think of where we’ll be in another hundred.
Slaving in the rice paddies for our Chinese overlords...
“Slaving in the rice paddies for our Chinese overlords...”
...and speaking Spanish.
Wait, what?
Believe it's called the *Go Splat* theory of photons, LOL.
Strictly the from the photon's point of view.
Since zero time runs for it (traveling at 186,000 miles per second), distance traveled is also zero (length contraction is infinite).
To us it may have traveled a billion light years for a billion years, but to it no time or distance was traveled.
With no time running for it (speed of light, time stopped thing), when it finally hits something, you can say from its' point of view it was both created and destroyed in the same instant.
I probably botched up the explanation from what I remembered, but it makes sense to me a little.
“you can say from its’ point of view it was both created and destroyed in the same instant.”
Well, that explains religion.
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