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## Neutrino Speed

According to the Albert Einstein theory, speed of light is the Universe’s ultimate speed limit, but an experiment that have been carrying by Dr Ereditato and his team for last three years suggest neutrinos can travel faster then light.

This puzzling result from Cern has to be investigated for possible errors. As Dr Ereditato says:
We are not claiming things, we want just to be helped by the community in understanding our crazy result -
because it is crazy

More about experiment (OPERA detector, measurement methods, data selection, conclusions) you can read on
“Measurement of the neutrino velocity with the OPERA detector in the CNGS beam”
http://arxiv.org/ftp/arxiv/papers/1109/1109.4897.pdf

The OPERA neutrino experiment at the underground Gran Sasso Laboratory has measured the
velocity of neutrinos from the CERN CNGS beam over a baseline of about 730 km with much higher
accuracy than previous studies conducted with accelerator neutrinos. The measurement is based on highstatistics
data taken by OPERA in the years 2009, 2010 and 2011. Dedicated upgrades of the CNGS
timing system and of the OPERA detector, as well as a high precision geodesy campaign for the
measurement of the neutrino baseline, allowed reaching comparable systematic and statistical accuracies.
An early arrival time of CNGS muon neutrinos with respect to the one computed assuming the speed of
light in vacuum of (60.7 ± 6.9 (stat.) ± 7.4 (sys.)) ns was measured. This anomaly corresponds to a relative
difference of the muon neutrino velocity with respect to the speed of light (v-c)/c = (2.48 ± 0.28 (stat.) ±
0.30 (sys.)) ×10-5.

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### 3 Responses to “Neutrino Speed”

1. carnosine eye drops says:

Neutrinos do have mass, which means that they do not travel exactly at the speed of light. But because they are so light, they are very close to the speed of light, even for relatively “low” neutrino energies. Neutrino mass is on the order of a fraction of one eV, typical neutrino energies are MeV to TeV, i.e. the kinetic energy of neutrinos is millions to trillions of times larger than their rest mass energy.

2. carnosine eye drops says:

Last year, OPERA measured that neutrinos were making the 454-mile (730-kilometer) underground trip between the two labs more speedily than light, arriving there 60 nanoseconds earlier than a beam of light would.

3. Update 23-Sep-2011: The news is now officially out with a CERN press release and an arxiv submission at http://arxiv.org/abs/1109.4897 The result they have obtained is that the neutrinos arrive ahead of time by an amount 60.7 ns ± 6.9 ns (statistical) ± 7.4 ns (systematic). On the face of it this is a pretty convincing result for faster than light travel, but such a conclusion is so radical that higher than usual standards of scrutiny are required.