A protracted-running experiment finds a tiny particle remains to be appearing bizarre

The ring-shaped observe that scientists used to check tiny particles known as muons on the Fermi Nationwide Accelerator Laboratory close to Chicago, 2023.
| Picture Credit score: AP
Ultimate outcomes from a long-running U.S.-based experiment introduced Tuesday present a tiny particle continues to behave unusually — however that is nonetheless excellent news for the legal guidelines of physics as we all know them.
“This experiment is a large feat in precision,” mentioned Tova Holmes, an experimental physicist on the College of Tennessee, Knoxville who is just not a part of the collaboration.
The mysterious particles known as muons are thought-about heavier cousins to electrons. They wobble like a high when inside a magnetic area, and scientists are learning that movement to see if it traces up with the foundational rulebook of physics known as the Commonplace Mannequin.
Experiments within the Sixties and Nineteen Seventies appeared to point all was nicely. However checks at Brookhaven Nationwide Laboratory within the late Nineties and early 2000s produced one thing surprising: the muons weren’t behaving like they need to.
Many years later, a world collaboration of scientists determined to rerun the experiments with a good greater diploma of precision. The staff raced muons round a magnetic, ring-shaped observe — the identical one utilized in Brookhaven’s experiment — and studied their signature wiggle on the Fermi Nationwide Accelerator Laboratory close to Chicago.
The primary two units of outcomes — unveiled in 2021 and 2023 — appeared to verify the muons’ bizarre conduct, prompting theoretical physicists to attempt to reconcile the brand new measurements with the Commonplace Mannequin.
Now, the group has accomplished the experiment and launched a measurement of the muon’s wobble that agrees with what they discovered earlier than, utilizing greater than double the quantity of information in comparison with 2023. They submitted their outcomes to the journal Bodily Evaluation Letters.
That mentioned, it is not but closing time for our most simple understanding of what is holding the universe collectively. Whereas the muons raced round their observe, different scientists discovered a technique to extra intently reconcile their conduct with the Commonplace Mannequin with the assistance of supercomputers.
There’s nonetheless extra work to be executed as researchers proceed to place their heads collectively and future experiments take a stab at measuring the muon wobble — together with one on the Japan Proton Accelerator Analysis Complicated that is anticipated to begin close to the top of the last decade. Scientists are also nonetheless analyzing the ultimate muon information to see if they’ll glean details about different mysterious entities like darkish matter.
“This measurement will stay a benchmark … for a few years to come back,” mentioned Marco Incagli with the Nationwide Institute for Nuclear Physics in Italy.
By wrangling muons, scientists are striving to reply basic questions which have lengthy puzzled humanity, mentioned Peter Winter with Argonne Nationwide Laboratory.
“Aren’t all of us curious to grasp how the universe works?” mentioned Winter.
Revealed – June 04, 2025 04:15 pm IST