The L.H.C. could reveal the nature of matter and confirm physicists’ best guesses about the validity of string theory. These would be advances comparable to Einstein’s or Newton’s — but they are possibilities only because we do not know what will happen when we switch the contraption on. Scientists protest that the probability of their experiments’ causing the end of the universe is astronomically low, and they are telling the truth. But tinkering with the unknown is what experimental science is all about, and even the scientists must admit that there is a chance of doomsday (and, indeed, a chance of many other things) in any project like this.
Is it worth the risk? Absolutely. This is not the first time scientists have wondered whether their experiments might cause the world to end. Late-medieval bioethicists frowned on a branch of alchemy that involved isolating semen in flasks. Alonso Tostado (bishop of Avila and a sort of Leon Kass of his day) thought semen, if not tempered with menses, could grow into an army of demonic beings with supernatural gifts. He hypothesized that the wizard Merlin, as well as the entire fearsome race of Huns, had been products of exactly this diabolical tinkering, and that further exploration could be cataclysmic. Five centuries later, Edward Teller worried that heat from the first atomic bomb test would ignite the atmosphere and send a wall of fire racing across the earth, reducing to cinders every man, woman, and child. (Teller’s report, declassified in 1973, declared that a world-engulfing chain reaction was “not likely.”)
During the construction of the Relativistic Heavy Ion Collider in Long Island, physicists considered many of the same armageddon scenarios that dog the LHC today. In addition to black-hole fears, they entertained the possibility that it could create a “strangelet” — a Midas-material that converts everything it touches into hyper-dense “strange matter,” rapidly shrinking the planet into a heavy sphere about 100 meters across. Worse still, some thought the RHIC could spark a chain reaction that catalyzes the decay of all protons in the universe, starting with the Earth and radiating outward at the speed of light. The laboratory concluded that they had excluded the possibility of destroying the earth with “a very high level of confidence.” The RHIC has been operating without incident for nearly eight years.
There is a philosophically dense issue of observational selection bias at work here. (We wouldn’t be around in 2008 to observe a world that ended in a firestorm in 1945, or with a black hole in 2000.) That nontrivial caveat aside, though, we can say with total confidence that the history of doomsday prophecy in science has, so far, been a history of false prophecy. So far.
Originally appeared at TheAtlantic.com