You may have heard about a particle-physics experiment called OPERA, which seems to have measured neutrinos coming from the CERN accelerator traveling faster than the speed of light. If confirmed, this result would be extremely exciting and intriguing, as it would modify the foundations of all physics for the past 100 years.
The physics community seems to accept that the team at OPERA did a professional and thorough job, but naturally, there is also widespread skepticism. The effect they measured might be explained simply by some systematic error of 60 nanoseconds, although finding the source of the error itself could be interesting. In the next year or so, laboratories in the U.S. and elsewhere should be able to independently test the result.
A professor of particle physics told me and some other students, "It should be looked into with an open and skeptical mind." She's seen many extraordinary discoveries and disappointments in her 50 years as a physicist, so I guess she would know.
Just for fun: below is a video of how to build your own cloud chamber, a simple device which forms visible tracks as particles fly through it (go to 3 min. 10 sec. in the video to watch the tracks). Watching the tracks is fun and mesmerizing, and you don't actually need any radioactive samples like the one used in the video; unless you live in a lead box, an empty chamber will produce a frenzy of zig-zagging tracks due to the ambient particles raining down on us every day (mostly muons).
Very interesting Freyguy. I was planning on discussing this with you at some point. It would be pretty amazing if true but you are right in that there should definitely be some skepticism about it. We will have to see if it can be independently repeated by the other labs.
ReplyDeleteWhat is your gut feeling on whether it will turn out to be a true result or not? Any thoughts on what the systematic error would be if it is not actually true?
My gut feeling is that I just don't know! I can't wait to find out. The folks at OPERA are not claiming the neutrinos traveled faster than light, they are only saying "We have an anomalous result. Please check it." I do not know what the systematic error could be, but according to Nature the GPS system is coming under scrutiny.
ReplyDeleteNeutrinos are somewhat special. We still do not know if they have a tiny mass, or if they are massless. We only learned in the last 10 years or so that the three neutrino "flavors" are actually the same particle oscillating between three states.
I do have a gut feeling that even though this result may not be real, there are momentous physics discoveries awaiting us. We don't understand 96% of the matter and energy in the universe. We haven't found gravitational waves or supersymmetric particles. And we can't reconcile gravity and quantum mechanics. So we know there's a lot we don't know.