Cheese and a Ferengi: Naming Quarks

Naming Quarks: Physicist Flights of Fancy

Particle physics is not a subject that seems like it would be associated with the word ā€œwhimsyā€. Itā€™s basically the go to stereotype for srs bsns scientist. We’ve seen that astronomers can be very literal in their naming. But then there is the amazing whimsical world of naming quarks. A world which has nothing to do with any bartenders on space stations. Or German cheese.

Cheese and a Ferengi: Naming Quarks

It’s an interesting disambiguation page to say the least

The word atom comes from Greek, meaning ā€œunable to cutā€. The idea was that these were the smallest particles that made up everything. Of course, then we discovered that atoms were made up of protons, neutrons and electrons, which we decided to call elementary particles. When the protons and neutrons (but not the electrons!) turned out to be made up of something even smallerā€¦ well, this time they learned their lesson and decided to just pick a nonsense word out of Finneganā€™s Wake. Always make literary references in science when you can!

Naturally decades later quarks are still as small as weā€™ve managed to go, partly because they canā€™t actually be directly observed. Itā€™s remarkably difficult to determine something you canā€™t actually observe is made up of even smaller bits.

Possibly because they were already dealing with strange and abstract particles, physicists decided to refer to the different kinds of quarks as ā€œflavoursā€. The six flavours exhibit varying degrees of whimsy in their naming.

A Brief History of Naming Quarks

The first three quarks proposed were up, down andā€¦ strange. Up and down quarks are the ones that make up protons and neutrons, with up being positively charged and down being negative. Iā€™m not entirely clear on why they didnā€™t get called the positive and negative quarks, especially since up and down are typically terms associated with a different property entirely. Strange quarks were so named because the particles made up of them had strangely long lifetimes.

neutron quark structure up down down

A neutron: Two down quarks and an up quark give a charge of zero

In 1970, Glashow and Iliopoulos and Maini proposed a fourth quark, serving as a counterpart to the strange quark much like top and bottom. Scientists really have a thing about symmetry (donā€™t get chemists started on snowflake pictures that donā€™t have C6 symmetry!), so physicists were quite charmed by the symmetry this fourth quark brought to the model. And so, on by what most accounts call a whim, they named it the charm quark. The first charmed particles were observed in 1974.

In 1973, Kobayashi and MaskawaĀ proposed that there must be yet another pair of quarks to explain variations in a particular decay pattern. They eventually won the Nobel Prize for this work in 2008, so needless to say there wound up being some support for it. Half the pair was confirmed in 1977 but the other quark had to wait until 1998. Sadly, attempts to name these quarks beauty and truth did not catch on and they wound up with the far duller names of top and bottom. That said, particle accelerators that produce a lot of bottom quarks are called beauty factories. Because who can resist calling your big expensive science equipment that?