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Muons: 'Strong' evidence found for a new force of nature
Physicists may have just made a major breakthrough in our understanding of the Universe.

A breakthrough experiment in particle physics suggests an unknown force:
"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 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."
Another article, with more scientific terms that might be hard to understand:

New experiment hints that a particle breaks the known laws of physics
A heavier sibling of an electron, known as a muon, is challenging the "Standard Model" of all the particles in the universe.