Sunday, January 14, 2018

Table-Top Elementary Particle Experiment

I love reading articles like this one, where it shows that one can do quite useful research in elementary particles using experimental setup that is significantly smaller (and cheaper) than large particle colliders.

Now, he’s suddenly moving from the fringes of physics to the limelight. Northwestern University in Evanston, Illinois, is about to open a first-of-its-kind research institute dedicated to just his sort of small-scale particle physics, and Gabrielse will be its founding director.

The move signals a shift in the search for new physics. Researchers have dreamed of finding subatomic particles that could help them to solve some of the thorniest remaining problems in physics. But six years’ worth of LHC data have failed to produce a definitive detection of anything unexpected.

More physicists are moving in Gabrielse’s direction, with modest set-ups that can fit in standard university laboratories. Instead of brute-force methods such as smashing particles, these low-energy experimentalists use precision techniques to look for extraordinarily subtle deviations in some of nature’s most fundamental parameters. The slightest discrepancy could point the way to the field’s future. 

Again, I salute very much this type of endeavor, but I dislike the tone of the title of the article, and I'll tell you why.

In science, and especially physics, there is seldom something that has been verified, found, or discovered using just ONE experimental technique or detection method. For example, in the discovery of the Top quark, both CDF and D0 detectors at Fermilab had to agree. In the discovery of the Higgs, both ATLAS and CMS had to agree. In trying to show that something is a superconductor, you not only measure the resistivity, but also magnetic susceptibility.

In other words, you require many different types of verification, and the more the better or the more convincing it becomes.

While these table-top experiments are very ingenious, they will NOT replace the big colliders. No one in their right mind will tell CERN to "step aside", other than the author of this article. There are discoveries or parameters of elementary particles that these table-top experiments can study more efficiently than the LHC, but there are also plenty of the parameter phase space that the LHC can probe that can't be easily reached by these table-top experiments. They all are complimenting each other!

People who don't know any better, or don't know the intricacies of how experiments are done or how knowledge is gathered, will get the impression that because of these table-top experiments, facilities like the LHC will no longer be needed. I hate to think that this is the "take-home" message that many people will get.