This is probably about the neutrinos. They sent of a load of particles called neutrinos from one place into a huge detector several miles away. They timed it really accuratly and found that the neutrinos were traveling faster than the speed of light. However, even the people who run the experiment aren’t conivinved by their results, but couldn’t find where they went wrong. The reason they publisehd their results was more so that other scientists could come and find their mistake.
no, they measured the arrival time of neutrinos, and neutrinos seemed to travel faster than light, which is against special relativity (a theory that is tested every day in all laboratories in the world), so if it was true, all physics books written in the last 100 years should be re-written. It would be great, but it is more likely an experimental mistake, since another experiment, measuring the same quantity in Gran Sasso, measured that neutrinos travel at the speed of light, as expected. There will be another experimental campaign in May, and the final word will be hopefully said there.
Actually they didn’t discover that! It turns out they made a mistake in their experiment and got an incorrect result! (they had actually forgotten to tighten up the connector on a cable in the back of a computer). When they fixed the problem and re-did their experiment they found that the neutrinos they were measuring were travelling at the speed of light, not faster than it as they had previously thought.