[Muta]

Muons: 'Strong' evidence found for a new force of nature

https://www.bbc.com/news/56643677

All of the forces we experience every day can be reduced to just four categories: gravity, electromagnetism, the strong force and the weak force.

Now, physicists say they have found possible signs of a fifth fundamental force of nature.

The experiment, based at the Fermi National Accelerator Laboratory (Fermilab) in Batavia, Illinois, searches for signs of new phenomena in physics by studying the behaviour of sub-atomic particles called muons.

There are building blocks of our world that are even smaller than the atom. Some of these sub-atomic particles are made up of even smaller constituents, while others can't be broken down into anything else (fundamental particles).

The muon is one of these fundamental particles; it's similar to the electron, but more than 200 times heavier.

The Muon g-2 experiment involves sending the particles around a 14-metre ring and then applying a magnetic field. Under the current laws of physics, encoded in the Standard Model, this should make the muons wobble at a certain rate.

Instead, the scientists found that muons wobbled at a faster rate than expected. This might be caused by a force of nature that's completely new to science.