• View of the OPERA detector (on the CNGS facility) with its two identical Super Modules, each one containing one target section and one spectrometer

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3 Questions: Faster than light?

MIT physicist Peter Fisher answers questions about reports that experiments in Switzerland and Italy show neutrinos can break light’s speed limit.


The news media were abuzz this week with reports of experiments conducted at the Gran Sasso particle detector complex in Italy, apparently showing subatomic particles called neutrinos had traveled from the giant particle accelerator at CERN, outside Geneva, to the Italian detector at a speed just slightly faster than the speed of light — a result that, if correct, would overturn more than a century of accepted physics theory. Professor of Physics Peter Fisher, head of MIT’s Particle and Nuclear Experimental Physics division, answered some questions about these new findings.

Q. If this result is confirmed, does it really undermine Einstein’s theory of relativity, as some news reports claim? And if so, is there a theory that’s been proposed that might account for it?

A. Einstein’s theory rests on two postulates, one of which is that electromagnetic radiation travels at the same speed (the speed of light, 300,000 kilometers per second) no matter how the observer moves. Light particles — photons — have no mass, so a consequence is that no particle with mass can move at a velocity greater than light. These neutrinos have a tiny, but non-zero, mass and hence should not be able to travel faster than the speed of light.

There are theories that predict particles moving faster than the speed of light, but, to my knowledge, none of them account for all the other phenomena we have measured experimentally since the time of Einstein.

Q. What kind of other tests or independent experiments would it take to confirm this result so that it would be widely accepted?

A. There are two other experiments that shoot neutrinos over long distances that may have something to say about this result. One experiment is in the U.S., and the beam goes from Fermilab, near Chicago, to a detector called MINOS in northern Minnesota. The other shoots a neutrino beam across Japan to an experiment in a mine called Super-Kamiokande. The energies of the neutrinos in these experiments are much lower than the CERN beam, but they may have something to say very soon.

Q. If this turns out to be some kind of unrecognized systematic error in the measurements, would that reflect badly on the scientists who reported it, or would it just be a reflection of science working as it’s supposed to?

A. I would say more the latter. I know a number of the people on the OPERA experiment [at Gran Sasso] and they are very thoughtful, careful people who would never publish a result like this unless they were certain there was no better explanation. I would bet that whatever the explanation is, it will be very interesting.


Topics: 3 Questions, CERN, Neutrinos, Physics

Comments

If this is the case, how is light able to be trapped and drawn into a black hole?
Good analysis by MIT Physicist Peter Fisher. But the question is whether light travels faster than mind? Dr.A.Jagadeesh Nellore(AP),India
In 1932 Nikola Tesla reported that neutrons are small particles, each carrying so small a charge and they travel with great velocity, exceeding that of light. Experimental tests of Bell inequality have shown that microscopic causality must be violated, so there must be faster than light travel. According to Albert Einstein's theory of relativity, nothing with nonzero rest mass can go faster than light. But zero rest mass particles can go faster than the light. Neutrinos have a small nonzero rest mass. Faster than light interactions are a necessity and they provide the non local structure of the universe. We should understand the relation between local and nonlocal events like the dynamics of universal structure. In any physical theory, it is assumed that there is some kind of nonlocal structure violates causality. If neutrinos are traveling faster than light, then neutrinos must be on the otherside of the light barrier going backwards in time, where the future can interact with the past. There are lots of theories and research regarding this matter including Cherenkov radiation, Standard Model Extension, Heim theory, Novikov selfconsistency principle, Casimir effect, Hartman effect, Casimir vacuum & quantum tunnelling, Tachyons, etc. - Nalliah Thayabharan
Does it imply that slowing down of time is not possible?
Kirk: "Scotty, I need more power!" Engineer Scott: "Captain, the matter antimatter reactors canna take it any more." However they folks at CERN resolve this very small discrepancy, I hope it yields new knowledge.
If such result is to be true, what would it mean to us now that something is faster than speed of light?
Jagadeesh: The Einstein-Podolsky-Rosen effect (EPR) declares that information, as involved in quantum entanglement, has no speed limit. If this were not the case, it would follow that the Heisenberg Uncertainty Principle could be rather easily violated by, for instance, sneaking observations of each of a entangled pair of photons in widely separated labs before the measurements made in one lab could become 'known' to the other lab. But as experiments at the University of Innsbruck confirmed, it is not possible to "trick" entangled photons. Apparently, information 'travels' infinitely fast. Is this because, as Bishop Berkeley answered affirmatively to the question "If a tree falls in a deserted forest, does it make a sound?", because God sees and hears everything at all times? johnnysbug: light is trapped by the warping of space-time, not because it has mass like an apple.
Although light has no mass, given the high speeds of a Photon, there is such a thing as relative mass, it is due to this relative mass that black hole is able to be trapped in a black hole. This was the explanation they gave me at my university.
In my theory on why neutrinos travel faster then light is due to the fact of gravity's effect on momentum, it increases then final force. For this to be true you would need to replicate this in space, or somewhere were there is no momentum and unbalanced forces being applied. Which in turn reduces friction also possibly increasing the speed even more. - Jordan Nelson
What about Hawking's Radiation? How are these findings different from those?
What if a neutrino has a slightly imaginary mass which in QFT indicates that the particle will decay slowly? And according to the theory of relativity, a slightly imaginary mass leads to faster-than-light phenomenon. And what if a neutrino is not an elementary particle? if a neutrino has a more detailed structure and not a point, the Lorentz group's continous symmetry will break and lead to a Faster-Than-Light phenomenon.
With little knowledge about classical physics and relativity theories, i assume CERN’s neutrinos were experienced Lorenz Transform (Lorenz Shortening). Electromagnetic waves would not experience Lorenz Transform because they have no mass. As with a tiny mass just not equal to zero, neutrinos travel in nearly light speed are experienced Lorenz Transform where they enter one point and come out at another point far away instantanously in a condition where the space field was compressed and bended (or even folded) in higher dimensional perspective.Satellites could not detect this because they did not detect the compression of space field (even though it is a very hard solid as it was happened underground i still prefer to call it space field).Faster-than-light neutinos was something like a illusion as it happened before when there is an experiment done underwater to find out tachyon.
i wish to point out here, something that every physicist know but may not notice that Observed Speed is not same with Actual Speed, make a simple example from general relativity, a spacecraft was attracted and absorbed by a black hole, then it travel at a speed below light's speed in the worm hole and came out as a wreckage (in particles form)from the connected white hole; now, its wreckage may located at 100 light-years away from its origin, if the process take 10 minutes, then the Observed Speed is 100 light-years (in km)/10 minutes (in seconds),the Observed Speed should obviously far more faster than light's speed, however, in that whole process, the spacecraft (and its wreckage) never travel faster than the light's speed. It is its Actual Speed.
i wish to proposed a mathematical idea for Observed Speed and Actual Speed. It is not a proven and scrutinized mathematical formula but just to give a clearer picture. If Observed Speed = Distant/Time, then Actual Speed = (Distant)(Space Higher Dimensional Shortcut Variable) / (Time)(Relativitic Time Variable) where (Space Higher Dimensional Shortcut Variable) is < 0 and depending on space field density, space field curvature , Lorenz shortening,etc. and (Relativistic Time Variable) is > 0 on the fact that moving object i.e. neutrinos and static object i.e. detector/observor have different properties of time. Conclusion, as the observor (static object) and neutrinos (moving object) have no Absolute Time and have no Absolute Space, we could not simply conclude that neutrinos is travel faster than light just becoz that experiment was fully scrutinized done.
Sorry for a part of mistake, the correction should be: the Actual Speed = (Distance) (Space Higher Dimensional Shortcut Variable) / (Time) (Relativitic Time Variable) where (Space Higher Dimensional Shortcut Variable) is less than 1 and is depending on Space Field Density, Space Field Curvature and Lorenz Shortening, etc. and (Relativitic Time Variable) is greater than 1 , on the fact that Detector or Observor (static object) and Neutrinos (moving object) have different properties of time.
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