It is very unlikely that Fermilab’s new findings on the mass of the Wboson mean that the standard model is broken. It will be exciting if it does. This is not to say that their experimental findings are wrong. Fermilab themselves propose the much more likely possibility that we need to compute the predicted values more precisely in the standard model. Another possibility that occurs to me is that we scientists need to both compute the values predicted by established theory even more precisely and also extend the established theory a little bit.

That’s the key to understanding this story. I strongly recommend that the interested public read their tweets on this.

What Is The Standard Model

The Standard Model of Particle Physics is tied with General Relativity for being the most tested scientific theory ever. Dozens of experiments agree within their collective precision on what the key values it predicts are. The Standard Model of Particle Physics predicts the masses and other properties of fundamental particles such as quarks (which comprise protons and neutrons), electrons (and particles like them). The aforementioned being a class of particle called a fermion. Because fermions cannot be in the same quantum state at the same place at the same time, they are what we tend to think of as matter.

The standard Model is often presented in this form for the public.

This is the standard model in its final form. Its so complex that it is possible that even the scientists who work with it approximate the predictions it makes. In most cases the field equations derived from it will not have exact analytical results.

The other class of particles are called bosons. Bosons are particles such as photons of light which can be in the same quantum state in the same place at the same time. Photons carry the familiar electromagnetic force. The Graviton would carry the force of gravity. The particles which carry the inner atomic strong and weak forces are different. The Strong Force is carried by a particle called a gluon, which only acts between quarks. Meanwhile the weak nuclear force is carried by particles called the W and Z bosons. As Fermilab puts it

With any scientific work a formally published paper is the best place to look for all of the information. As the interested public a good paper will have an abstract, or summary, which should be understandable. Theoretical physicists will have something new to work with. I agree with the related perspective on this published in the journal science by Claudio Campagnari and Martijn Mulders. There is a lot to be done to confirm this.

Between now and then us theorists will have something new to play with. Expect to hear of how this could be a hint at new particles, new fields, or breath some new life into super string theory / M theory etc. Not to belittle these things my own current work is about extensions and modifications to General Relativity.

This is a claim that will have to be followed up on and confirmed with further data. Until then physicists will have something new to talk about.


“High-precision measurement of the W boson mass with the CDF II detector” CDF Collaboration†‡T. AaltonenS. AmerioD. AmideiA. Anastassov et al. Science • 7 Apr 2022 • Vol 376, Issue 6589 • pp. 170-176 DOI: 10.1126/science.abk1781

“An upset to the standard model” Claudio Campagnari and Martijn Mulders Science • 7 Apr 2022 • Vol 376, Issue 6589 • p. 136 • DOI: 10.1126/science.abm0101