In the meantime, in 2020 a gaggle of 170 specialists often called the Muon g-2 Concept Initiative revealed a new consensus value of the theoretical value of muon’s magnetic moment, based mostly on three years of workshops and calculations utilizing the Customary Mannequin. That reply bolstered the unique discrepancy reported by Brookhaven.
Reached by telephone on Monday, Aida X. El-Khardra, a physicist on the College of Illinois and a co-chair of the Muon g-2 Concept Initiative, stated she didn’t know the end result that Fermilab can be asserting two days later — and she or he didn’t need to, lest she be tempted to fudge in a lecture scheduled simply earlier than the official unveiling on Wednesday.
“I’ve not had the sensation of sitting on scorching coals earlier than,” Dr. El-Khadra stated. “We’ve been ready for this for a very long time.”
On the day of the Fermilab announcement one other group, utilizing a distinct method often called a lattice calculation to compute the muon’s magnetic second, concluded that there was no discrepancy between the Brookhaven measurement and the Customary Mannequin.
“Sure, we declare that there isn’t any discrepancy between the Customary Mannequin and the Brookhaven end result, no new physics,” stated Zoltan Fodor of Pennsylvania State College, one of many authors of a report published in Nature on Wednesday.
Dr. El-Khadra, who was accustomed to that work, known as it an “superb calculation, however not conclusive.” She famous that the computations concerned had been horrendously sophisticated, having to account for all potential ways in which a muon might work together with the universe, and requiring 1000’s of particular person sub-calculations and lots of of hours of supercomputer time.
These lattice calculations, she stated, wanted to be checked in opposition to impartial outcomes from different teams to remove the opportunity of systematic errors. For now, the Concept Initiative’s calculation stays the usual by which the measurements shall be in contrast.