Neutrinos Faster Than Light? Probably Not

Boy, the press drives one mad. Bonkers, even.

Especially the complete fantastic extrapolations when it comes to science. They have happened here too many times to list, even, but there is yet another new one today.

Scientists at CERN have been measuring some neutrinos for the last three years. Over time, they noticed that one or some neutrinos were arriving nanoseconds earlier than they should have been. And this means, if you divide the distance they travelled by the number of nanoseconds it took for them to travel, that they were traveling faster than light. Confused by this, they published their results in hope that someone would find, in their words, a systematic error. In other words, something here is not right and we cannot figure it out. Can someone else help?

Now, the press is flooded with grandiose claims that Einstein was wrong, that particles are moving faster than light, and that all of physics must be rewritten!!!!11!1one!!eleventy!!%cake!!

Let us lighten up. We have some strange measurements that may or may not be related to the actual, original experiment. And the scientists, as they should, took a gander at the weird results, realized this was out of their areas of expertise, and published their results in hope that someone would find their error—because if this is wrong, their other findings could be wrong, too. This is perfectly reasonable and sensible science.

So we need to wait and see what the review actually says before chucking Einsteinian relativity out the window, which has been pretty well vetted and shown to be both astonishingly reliable but also very precisely predictive of the tiniest things as well as the biggest.

But let us review. Light travels 186,282.3976 miles per second in a vacuum. Light travels slower through other media, and it is possible for objects to travel faster than light when run through sloppy, viscous materials. However, in a vacuum, light is considered to be the fastest thing there is.

Why? It comes down to momentum (and other things, but this concept is pretty easy). When a canned ham moves at familiar speeds, its momentum can be defined as its mass times its velocity times something called its gamma. Gamma measures the effects of relativity on an object, and is shown by the formula up and to the right. At normal canned ham speeds, gamma is nearly zero and you don’t even notice it. At faster speeds, it increases a lot.

At light speeds, gamma becomes so large that it takes increasingly more energy to move that canned ham faster. So big, that in effect you need infinite energy to overcome infinite momentum, as if the object had infinite mass. And the more power you dump into it, the more effective mass you create, so it becomes a lose-lose. It would take all the energy you could muster, and you still would not quite get it as fast as light.

The photon, which carries what we perceive as light in all its forms, has no effective mass. So no matter how fast the little photon goes, its mass stays zero—even with the whopping huge gamma value. So it can travel at the speed of light all day long, and not need any real energy to do so. On the other hand, every other particle has a teeny-tiny amount of mass, and so cannot travel at the speed of light without having relatively infinite amounts of momentum.

So we conclude that only light can travel at the speed of light. But why does light travel 186,282.3976 meters per second and no faster? It winds up being that gamma thing again. As you go faster, the speed of time slows by gamma. As you hit that particular speed (the speed of light), time moves with effectively infinite gamma, which means time does not move at all for the light particle. Time stops at that exact velocity.

And so, if any particle were to move faster than 186,282.3976 miles per second, it would be going backward in time. This in fact is one of the easiest indicators that something is odd with the CERN numbers: the neutrons are arriving just a wee bit faster than that, but are not arriving before they are transmitted. They are somehow moving faster than light but without infinite gamma. Therefore, something is definitely wrong with this experiment.

In fact, there are much better experiments to test whether particles can go faster than light. Many, in fact, and all have failed. For example, looking at a supernova. The neutrinos arrive from a distant supernova slightly after we see the light from its explosion. If the CERN numbers were correct, we should see neutrinos arrive hours or even days before the light from the supernova…but we do not. And the amount of neutrinos and photons we see from a supernova is a lot, yet the results are consistent.

If the CERN numbers were right, we would see these same kinds of neutrinos arrive before the light particles light up the source of the explosion.

Short answer: like most news stories that cover fundamental violations of physics, these usually wind up with easy explanations.

About The Czar of Muscovy

Божію Поспѣшествующею Милостію Мы, Дима Грозный Императоръ и Самодержецъ Всероссiйскiй, цѣсарь Московскiй. The Czar was born in the steppes of Russia in 1267, and was cheated out of total control of all Russia by upon the death of Boris Mikhailovich, who replaced Alexander Yaroslav Nevsky in 1263. However, in 1283, our Czar was passed over due to a clerical error and the rule of all Russia went to his second cousin Daniil (Даниил Александрович), whom Czar still resents. As a half-hearted apology, the Czar was awarded control over Muscovy, inconveniently located 5,000 miles away just outside Chicago. He now spends his time seething about this and writing about other stuff that bothers him.