Round and Round


by Brian Koberlein | 12 November 2018 | Physics

This is a companion discussion topic for the original entry at


I’m always amazed when I hear precision like this. Are you able to elaborate a bit on how they achieve such accuracy at these scales?


At one level, I’m glad to see more work that confirms the Standard Model. The Model serves well in the same way that Newtonian gravity and dynamics are adequate for space exploration within the solar system, and probably beyond. The Standard model is useful as long as we are working with “normal” matter, but agruably the model doesn’t accomodate dark matter, which is apparently the majority of matter in the universe. I find that disturbing.

Now here’s a line of thought regarding electrons and dark matter. We could argue that electrons interact with light, while dark matter does not interact with light. Therefore dark matter probably does not contain electrons. I guess you could apply this line of thinking to other particles in the Standard Model.

Are electrons “spherical” when they are acting as waves? I don’t know, an probably never will, because I’ll never “see” one. Electrons as waves, however, allow us to “see” atoms. In 1978 Peter Atkins opened his physical chemistry text with this.

“We know atoms and molecules exist because we can see them.”

Of course he was referring to electron microscopy.


It’s true that dark matter does not contain electrons. Nor does it contain any of the classes of particles we’re used to. Otherwise we would be able to see them just as we see everything else that makes ‘standard’ matter. That’s why it’s termed as dark matter.

It’s a class of matter we don’t understand. A lot of work has penned down what it isn’t, but not exactly what it is. Unlike other matter, it virtually never reacts with anything other than gravity (that we’ve detected so far). Even the elusive neutrino reacts at a far, far, far greater rate (and it doesn’t react all that often either).