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"All our sweetest hours fly the fastest." -Virgil
If you've been around the block once or twice, you know that the speed of light in a vacuum 299,792,458 meters-per-second is the absolute maximum speed that any form of energy in the Universe can travel at. In shorthand, this speed is known as c to physicists.
Muon’s Escalating Challenge to the Standard Model
April 7, 2021•
Physics 14, 54
Measurements of the muon magnetic moment strengthen a previously reported tension with theoretical predictions, ushering in a new era of precision tests of the standard model.
Reidar Hahn/Fermilab
g
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2 ring, where the precession of muons in a magnetic field is used to measure the muon magnetic moment.
Reidar Hahn/Fermilab
g
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2 ring, where the precession of muons in a magnetic field is used to measure the muon magnetic moment.×
Twenty years ago, the Brookhaven Muon
g
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2 experiment measured a value of the anomalous magnetic moment of the muon that disagreed by several parts per million with calculations based on the standard model (SM) of particle physics [1]. Physicists had long understood that the SM was incomplete, but the Muon
Scientific American
Is the Standard Model of Physics Now Broken?
The discrepancy between the theoretical prediction and the experimentally determined value of the muon s magnetic moment has become slightly stronger with a new result from Fermilab. But what does it mean?
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The Muon g-2 magnetic storage ring, seen here during its relocation from Brookhaven National Laboratory on Long Island to the Fermi National Accelerator Laboratory outside Chicago, is a central component of the project s quest for new physics. Credit: Alamy
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The so-called muon anomaly, first seen in an experiment at Brookhaven National Laboratory in 2001, hasn’t budged. For 20 years, this slight discrepancy between the calculated value of the muon’s magnetic moment and its experimentally determined one has lingered at a significance of about 3.7 sigma. That is a confidence level of 99.98 percent, or about a one-in-4,500 chance the discrepancy is a random fluctuation. With the just announce