Friday, September 23, 2011

Faster than light?

An experiment where a beam of neutrinos was fired from Geneva (CERN), to Gran Sasso, Italy, a distance of 730 kilometers, claims that the neutrinos reached their target 60 nanoseconds faster than a light beam would have, thereby violating a fundamental principle of special relativity, viz. nothing can travel faster than light.

Physics would undergo a stupendous change if it were true. The scientists who analysed the data said, "Although our measurements have low systematic uncertainty and high statistical accuracy, and we place great confidence in our results, we're looking forward to comparing them with those from other experiments". However, no one seriously believes this one; earlier claims of neutrinos that travel faster than light have not stood up to scrutiny. Still, this news item will have its moment of fame, so here is its blog post!

For a very clear discussion of the details of the experiment, see this link.

Tailpiece: A battered photon totters into a police station and tells a cop, "A bunch of neutrinos just beat me". The cop says: "Did you get a good look at them?" The photon says: "Heck, no, it all happened so fast!"

This blog post is by Neelima Gupte and Sumathi Rao.

9 comments:

AmOK said...

Thanks for that posting. I was thinking about what the erstwhile blogmaster would have said. These fast neutrinos - they perhaps will finally explain cold fusion, that one magnetic monopole and yes, poly-water. The causes for these effects will follow.

Neelima said...

Yes, very likely. However, it is nice to see physics in the newspaper headlines, instead of 1/2/3/4/G, riots, bombs, fasts, antifasts, agitations, accidents, terrorists, ........

vbalki said...

It's most amusing to see random comments (in the on-line versions of newspapers) by the great 'public' on the news. The best one I saw asked:"OK, so these neutrinos can travel faster than light. But can they travel faster thsn SOUND?"

Meena said...

Do neutrinos batter/scatter photons?

Neelima said...

Meena, neutrino-photon interactions do exist as far as I know, but they need a mediator (background field). Pl consult a neutrino expert, you have so many colleagues!

AmOK said...

So how long will other experimentalists take to check up on this? I remember cold fusion went on "producing heat" for a long, long time before it was ( was it? ) abandoned.What if some others now "find" that their neutrons are also "beating light"? More erroneous experiments?

AmOK said...

I guess I am getting impatient.

Neelima said...

Hello, Amok. Are you getting impatient about other experiments? There are two that can cross-check.The MINOS experiments sends neutrino beams from Chicago to a detector 450 miles away in Minnesota. The T2K experiment sends neutrinos across 180 miles from Tokai to Kamioka. The second had problems in the tsunami in March, and may not be any position to carry out the experimemt. The MINOS collaboration is planning more accurate experiments.

Meanwhile theorists, at least some, are not supporting the result. For a discussion see
here
.

AmOK said...

Neelima, many thanks! Interesting theoretical discussion on that link but somewhat obtuse, to the non-Smolin population. I will keep an eye on MINOS next time when my patience runs short. (Btw please note that I am AmOK and not Amok. My handle was a hidden message to an old friend)