Everything we know about physics could still be all turned on its head.
Back in September, scientists said that they discovered subatomic particles that can travel faster than light.
Now, they've gone back to the lab, fine-tuned the experiment, and the result?
Well, it seems to confirm the startling finding, as Atika Shubert explains.
Do they or don't they?
Those pesky neutrinos are back and stubbornly refusing to obey the laws of physics and slow down.
Remember this? In September, scientists announced some shocking results.
They shot a particle beam from Switzerland to Italy in 2.4 milliseconds. That's what it should take for a beam of light to cover that distance.
But neutrinos, those tiny subatomic particles with virtually no mass and no electrical charge,
well, they managed to arrive 60 billionths of a second faster than light.
Pandemonium in the world of physics, and here's why.
Energy equals mass times the speed of light squared. It's the bedrock of physics, Einstein's theory of relativity.
The fundamental principle: nothing can go faster than the speed of light.
Without that universal speed limit,
physics as we know it would unravel, allowing for such mind-bending stuff as time travel.
Of course, the problem with time travel is something called the Grandfather Paradox,
which means, if I've traveled back in time, and then I accidentally kill my grandfather,
which means, Atika, you would never have been conceived and, therefore, could not travel back in time to see yourself.
So, you can see why scientists went back to measure and remeasure, tweak and retweak the tests.
And on Friday, they announced this: those speedy neutrinos are still faster than light.
So, is Back to the Future suddenly a real possibility?
Scientists say two other labs in Japan and the U.S. are now conducting separate tests. But we won't get the results until next year.