A tiny particle may be about to reveal a fifth force of nature, say scientists behind one of the largest particle physics experiments ever.
Physicists at the Fermi National Accelerator Laboratory, or Fermilab, near Chicago have found more evidence that the muon, a subatomic particle, wobbles a lot more than it should, and they think it’s because an unknown force is pushing it.
The results are based on a previous one experiment conducted in 2021 but produced four times the data with the experimental uncertainty reduced by a factor of two. If the findings are true and the theoretical controversies surrounding these measurements can be overcome, they represent a breakthrough in physics of a kind not seen for 50 years, when the dominant theory solidified to explain subatomic particles.
In other words, the muon’s minute oscillation, known as its magnetic moment, has the potential to shake the very foundations of science.
“We’re really exploring new territory,” Brendan Casey, a Fermilab senior scientist working on the experiment, known as Muon g-2, he said in a statement. “We are determining the muon’s magnetic moment with better precision than has ever been seen.”
Related: Strange particle that can remember its own past created inside the quantum computer
Occasionally called “fat electrons,” muons are similar to electrons, but are 200 times heavier and radioactively unstable; they decay in just millionths of a second into tiny, ghostly, uncharged electrons and particles known as a. neutrinos. Muons also have a property called spin, which makes them behave like tiny magnets, making them wobble like mini gyroscopes when inside a magnetic field.
To investigate muon wobble, Fermilab physicists sent the particles flying around a minus-450-degree Fahrenheit (minus 268-degree Celsius) superconducting magnetic ring at nearly the speed of light, a speed that, because of the dilation of relativistic time, lengthens the short of the muons. lives by a factor of about 3,000.
By watching the muons wobble as they made thousands of turns around the 50-foot-diameter (15-meter) ring, the physicists gathered data that suggests the muon wobbles much more than it should.
The explanation, say the scientists in the study, is the existence of something that has not yet been explained Standard model — the set of equations that explain all subatomic particles, which has not changed since the mid-1970s.
This mysterious thing could be a completely unknown force of nature (the four known ones are gravitational, electromagnetic and the strong and weak nuclear forces). Alternatively, it could be an unknown exotic particle, or evidence of a new dimension or undiscovered aspect of space-time.
But whichever way you cut it, the physicists’ data suggest that something unknown is bumping and pulling the muons inside the ring.
However, full confirmation will take a little longer. To be as certain as possible, the physicists will use all the data collected during the g-2 experiment’s run from 2018 to 2023: the current result only takes data from 2019 and 2020. Second, they will have to wait for the theoretical predictions of the standard. Model to catch up.
There are currently two theoretical methods for calculating what the muon oscillation should be under the Standard Model. These two methods produce conflicting predictions. Some of these calculations, including one published the same week like the findings of the 2021 g-2 experiment, place a much larger value on the theoretical uncertainty of the muon’s magnetic moment, threatening to rob the experiment of its physics-breaking significance.
Another experimentusing data from the CMD-3 accelerator in Novosibirsk, Russia, also appears to find that muons wobble within normal limits, but the experiment directly contradicts an earlier run of the accelerator that suggested the opposite result.
Fermilab researchers hope that the full results, which they expect to be ready by 2025, can be precise enough to give a clear reading.
The scientists have submitted their work for publication in the journal Physical Review Letters; A preprint of the findings can be found here here.
English 
Español de Venezuela