By Don Lincoln, Fermilab
There are concerns put forth, at times, about the possibility that high-energy particle collisions could generate some sort of cataclysm of biblical proportions. Where do these concerns come from? Is there any scientific validity to them? And, of course, importantly, is there any actual danger?
Questioning the Safety of Particle Accelerators
The real origin of this fear is just a vague and nebulous concern, arising from uneasiness with the unknown and from a suspicion of authority. It springs from distrust of government and large corporations and it sits squarely in the shadow of things like Watergate and lies about the dangers of tobacco. On the more fantastical side, it is born from beliefs about Roswell and Area 51, chemtrails and the antivax movement.
And, of course, the problem is that some of those things are real and some aren’t, and it is very difficult for most people to know which is which, especially when one is talking about things as esoteric and unfamiliar as gigantic particle accelerators. How would ordinary people know if this is something to worry about, or not?
To understand this better, we need to dive into the history of this concern and some actual scientific reasons why it is perfectly reasonable to ask the question.
So, the first public discussion of these fears arose in 1999 in an exchange of letters in Scientific American between Walter Wagner and Frank Wilczek. Wagner was concerned of the danger and Wilczek was the voice of science. Wilczek, a Nobel Prize winner, was a very smart and well-educated physicist. Wagner held a doctorate in law, with a BS in biology and a minor in physics, so he did have some scientific training, but not the mastery of frontier science that Wilczek did.
This article comes directly from content in the video series The Evidence for Modern Physics: How We Know What We Know. Watch it now, on Wondrium.
Quarks
Getting specific, there were very specific worries that were put forth as potentially scientifically reputable worries about the safety of particle accelerators. The first one was regarding strangelets. The strangelet idea was independently proposed in 1971, by Arnold Bodmer, and again in 1984, by Edward Witten. The idea basically centers around a particular thought which was that ordinary matter consists of atoms, which have at their center protons and neutrons. Inside protons and neutrons, there are particles called quarks.
There are six types of quarks, but only two are generally found inside atoms, called up and down quarks. However, those other kinds of quarks exist. Usually the other four kinds are unstable and disappear in the wink of an eye—well, actually much faster than that. One of those unstable quarks is called the strange quark.
The Strangelet Idea
Now, scientists have certainly made subatomic particles with strange quarks in them. They’ve done that since the 1940s, but, they are unstable. However, what Bodmer and Witten both conjectured is that if we had enough strange quarks salted in with ordinary nuclear matter, then maybe this new matter would be stable, including the strange quarks.
That can’t happen in ordinary nuclei, mind you. But maybe if we had a ton of strange quarks, we might make some sort of super nucleus, consisting of up, down, and strange quarks. Although nobody has ever seen anything like this, but Witten posited that it could be true.
Under the right conditions, like smashing nuclei of particles together, we actually do make strange quarks. That’s real. So, the theory goes, that, under those conditions in large accelerators, we might make these subatomic particles, which go by the name ‘strangelets’.
A Subatomic Zombie Apocalypse
Now, depending on the properties of strangelets, which is worth noting are completely theoretical and have never been seen, it might be that bigger strangelets are more stable than smaller ones. And, if that’s so, then if a chunk of strangelet matter touched a chunk of ordinary matter, that ordinary matter would slowly convert over to strangelet matter.
In this way, a small bit of strangelet matter would grow bigger and bigger and, taken to the extreme, would eventually convert the entire Earth into strange matter. It’s kind of like some sort of subatomic zombie apocalypse, where one chunk infects others and pretty soon everyone is a zombie.
Thus, it’s worth underlining the fact that strangelets haven’t been observed, ever. It would not be a stretch to say that they probably are not even real. After all, if they were, they would have been made during the big bang and they’d still be around. Since we don’t see them anywhere, this is probably an idea that just isn’t true.
Common Questions about Particle Accelerators
The first public discussion of these fears arose in 1999 in an exchange of letters in Scientific American between Walter Wagner and Frank Wilczek. Wagner was concerned of the danger and Wilczek was the voice of science.
Depending on the properties of strangelets, which is worth noting are completely theoretical and have never been seen, it might be that bigger strangelets are more stable than smaller ones. And, if that’s so, then if a chunk of strangelet matter touched a chunk of ordinary matter, that ordinary matter would slowly convert over to strangelet matter.
The concern was that a small bit of strangelet matter would grow bigger and bigger and, taken to the extreme, would eventually convert the entire Earth into strange matter. It’s kind of like some sort of subatomic zombie apocalypse, where one chunk infects others and pretty soon everyone is a zombie.
