As described here, the OPERA project at Gran Sasso Laboratories recently published an article describing what appears to have been the detection of superluminal neutrinos coming from CERN. As Tommaso Dorigo explains in this blog post, new results from the ICARUS team at Gran Sasso seem to contradict that.
In short, work by Cohen and Glashow shows that superluminal neutrinos would loose energy via neutral-current weak-interaction radiation in a process similar to Cherenkov radiation. The ICARUS team examined their own existing body of neutrino data and found no evidence of this.
Other excellent write-ups on this:
- Starts With A Bang! Game Over for Faster-Than-Light Neutrinos?
- Matt Strassler, “Is the OPERA Speedy Neutrino Experiment Self-Contradictory?” (Written before the ICARUS results were released, but laying out the theoretical foundations nicely.)