I tried reading, then simply skimming, but this is over my head and I didn’t think I could get through it comfortably. I was hoping for a paragraph that summed up a simple explanation, but if there was one, it was further in than I got. Can anyone summarize for dummies what this means for our understanding of physics?
There's a particular particle, the kaon, which can be created. This particle is highly unstable, and so, decays rapidly into other particles. Ever so often, it doesn't decay down the normal route but instead decays into a pion. This is extremely rare (6 in a billion).
In physics, we have what's called the "standard model". It's our best guess as to how physics works at the fundamental level. It's incomplete, however, with multiple slight variations. This decay pathway is interesting because it is quite sensitive to differences between these models. By measuring the energy and ratio of the resulting mess, we can disguard some variants of the model (their predicted energy is too high or too low).
By using a large number of little measurements, like this, scientists can home in on the most accurate "standard model" variant. This, in turn, informs work on a deeper understanding of physics.
Basically, a decade's work to put a single new point onto a graph. A point that only theoretical physicists care about, and might, or might not be useful down the line. Welcome to modern physics.
To be fair those single points are important, they've led to things like nuclear energy and modern computers... come to think of it a lot of our modern technology is rather like the physics equivelent of exploiting an extreme edge case in a game physics engine.
It's just the creation of particles with an ultra-short lifespan, which then decay into other particles. Only there are more of this type than expected, but still within the tolerance of what the theory predicts. Additional tests are needed to say anything conclusive. That's just what they normally like to do at CERN, they're quite good at it. They also started the world wide web, back in the day.
The number of kaon to pion and neutrino/antineutrino decays the team observed is higher than the 8.4 per 100 billion predicted by the Standard Model, but it's still within the uncertainty parameters.
will this discovery make it easier for me to get isekai'd into another world where I'm the hero that's going to save the world with my big d magic skillz?
Wasn't the whole thing about the scientists in the Three Body Problem that they recognised that their work was being sabotaged by something enormously more powerful?
No. The scientists do not figure out that things are being meddled with until much later. The scientist suicides, especially the daughter of the woman who invites the aliens, committed suicide because everything they knew about physics had been "proven incorrect". It was all a lie, but they didn't know that.