>>12874995Particle phyics (high-energy physics, HEP) is based on the Standard Model. When it predicts something it is extremely accurate, however a lot of things are missing from it (gravity, dark matter...). Physicists then do two things:
1- Study things that aren't in the SM, and create new theories to explain them
2- Compare theory with experiments to try to find places where it seems to be wrong, and then try to explain why
Unfortunately, the Standard Model is still bulletproof, meaning physicists don't have many clues to work with
In the SM, the weak interaction allows a quark to change its flavor (its type). It is responsible for beta radioactivity, among other things
Quarks are usually grouped by 3 in hadrons (protons, neutrons...) or by 2 in mesons. The LHCb experiment studied a type of meson (the B meson) changing into another type of meson, as one its quarks transformed into another one. During this process, a pair of leptons are emitted
Leptons are a type of particle including electrons, muons and taus, and neutrinos. Electrons, muons and taus are identical in every way except their masses: the electron is the lightest and the tau the heaviest. Because they are identical the pair of leptons emitted should be any of the 3 types with equal probability. This is called lepton universality
The article explains that they observed more electrons than muons, suggesting that electrons have a higher chance to interact than muons. "3 sigmas" means there is a 1/1000 chance that their result may just be the result of statistical errors
Violation of lepton universality directly contradicts the SM, meaning that if it's true, there may be hints for new physics (a new type of particle, or a new interaction). Considering how successful the SM has been so far, physicists are excited to finally have something to look at
TLDR: some experiment appears to contradict the current theory of particle physics, this means there may be room for new theories to be discovered
