… and, much to a lot of peoples surprise – including mine – the previous result showing very slightly FTL travel time for the neutrinos has been repeated.
Neutrino experiment repeat at Cern finds same result
Initial analysis of the work by the wider scientific community argued that the relatively long-lasting bunches of neutrinos could introduce a significant error into the measurement.
Those bunches lasted 10 millionths of a second – 160 times longer than the discrepancy the team initially reported in the neutrinos’ travel time.
To address that, scientists at Cern adjusted the way in which the proton beams were produced, resulting in bunches just three billionths of a second long.
When the Opera team ran the improved experiment 20 times, they found almost exactly the same result.
Well, that’s… huh.
For the data to be really confirmed, it will have to be confirmed by other, unrelated groups of scientists using other hardware. But it’s not like you can pick up a neutrino generator at Ace Hardware and a neutrino detector at Wal Mart. Maybe eBay.
12 Responses to “FTL Neutrino experiment repeated”
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It’s still a timing glitch, most likely due to the relativistic effects of the GPS satellite orbital altitude compared to ground time.
They’ve removed one potential source of error. There’s still the tricky clock sync between both ends.
Concerning clock synchronisation – There is an article in the CERN Bulletin No 41/42 which gives some details. Not only GPS time signals are used but also caesium atomic clocks.
It would be more helpful if I gave the link!
http://www.google.ch/search?q=cern+2011-41-42-e-web.pdf
I think people make entirely too much out of the speed of light. I don’t know about this experiment, it will probably just turn out to be experimental error, but there are probably many faster than light processes in Nature. W e just haven’t discovered them yet. We don’t know everything.
> there are probably many faster than light processes in Nature
We know there are. However, we’ve yet to find any meaningful or useful FTL processes/phenomena.
1) Gravity seems to be instantaneous.
2) Point a theoretically perfect laser beam at one limb of Jupiter. Tap the laser with a fingernail, causing the laser to slew. The beam can *easily* cross the face of Jupiter at a speed much faster than light (a beam of light would take about half a second to pass through Jupiter, if it could; the laser “spot” could do so in a small fraction of a millisecond). Interesting, but useless.
3) Quantum tunnelling/teleportation seems to be instantaneous. Not yet certain if useful.
#3 remains my personal favorite hope for the neutrino experiment… rather than neutrinos traveling slightly FTL, they quantum tunnel a few meters in on jump. But more likely experimental error.
Sorry, messed up format. This was in reply to “Gravity seems to be instantaneous”.
> Einstein showed it was limited to the speed of light.
http://metaresearch.org/cosmology/speed_of_gravity.asp
“Abstract. Standard experimental techniques exist to determine the propagation speed of forces. When we apply these techniques to gravity, they all yield propagation speeds too great to measure, substantially faster than lightspeed. This is because gravity, in contrast to light, has no detectable aberration or propagation delay for its action, even for cases (such as binary pulsars) where sources of gravity accelerate significantly during the light time from source to target.”
The real test would be something currently outside the real of the physically possible: make a substantial mass suddenly appear or disappear at will. Such as make a Jupiter-mass appear in the blink of an eye out in deep space, and see how long it takes for the effects to be noticed at Earth. If GPS satellites start drifting at the same moment that the planet appears, then gravity’s effects are lightspeed-limited. If, on the other hand, the planet visually appears hours after the satellites start moving out of position, then the effects of gravity are FTL.
The experiment you suggest is essentially equivalent to gravity wave experiments:
http://en.wikipedia.org/wiki/Gravitational_wave
You don’t have to make the mass disappear, just wiggle back and forth. Big orbiting stars or black holes do this. Gravity waves have yet to be directly detected yet, but the indirect evidence is pretty convincing.
Gravity operating at light speed is the basis of General Relativity. If that wasn’t true, it would be a much, much bigger deal than a few neutrinos gone wild.
I admit to not having studied this in any great depth, but it’s my vague understanding there’s a difference between gravity waves and, err, gravity. If gravity itself travels at the speed of light, then the Earth does not orbit the Sun, but orbits where the Sun *appears* *to* *be.* I recall some computer simulations of such a setup, and planets rather quickly (as in dozens to hundreds of orbits) wander away from the system.
I miss John Archibald Wheeler, what with his ideas of mass without mass and charge without charge, geon holes, etc. If only he had lived a bit longer to see this…