A Tiny Particle’s Wobble Could Upend the Known Laws of Physics (NY Times)

 

“Evidence is mounting that a tiny subatomic particle seems to be disobeying the known laws of physics, scientists announced on Wednesday [April 7], a finding that would open a vast and tantalizing hole in our understanding of the universe.

“The result, physicists say, suggests that there are forms of matter and energy vital to the nature and evolution of the cosmos that are not yet known to science. The new work, they said, could eventually lead to breakthroughs more dramatic than the heralded discovery in 2012 of the Higgs boson, a particle that imbues other particles with mass.

“‘This is our Mars rover landing moment,’ said Chris Polly, a physicist at the Fermi National Accelerator Laboratory, or Fermilab, in Batavia, Ill., who has been working toward this finding for most of his career.

“The particle célèbre is the muon, which is akin to an electron but far heavier, and is an integral element of the cosmos. Dr. Polly and his colleagues — an international team of 200 physicists from seven countries — found that muons did not behave as predicted when shot through an intense magnetic field at Fermilab.

“‘The aberrant behavior poses a firm challenge to the Standard Model, the suite of equations that enumerates the fundamental particles in the universe (17, at last count) and how they interact. This is strong evidence that the muon is sensitive to something that is not in our best theory,’ said Renee Fatemi, a physicist at the University of Kentucky.

“The results, the first from an experiment called Muon g-2, agreed with similar experiments at the Brookhaven National Laboratory in 2001 that have teased physicists ever since. ‘After 20 years of people wondering about this mystery from Brookhaven, the headline of any news here is that we confirmed the Brookhaven experimental results,’ Dr. Polly said.

“At a virtual seminar and news conference on Wednesday, Dr. Polly pointed to a graph displaying white space where the Fermilab findings deviated from the theoretical prediction. ‘We can say with fairly high confidence, there must be something contributing to this white space,’ he said. What monsters might be lurking there?

“‘Today is an extraordinary day, long awaited not only by us but by the whole international physics community,’ Graziano Venanzoni, a spokesman for the collaboration and a physicist at the Italian National Institute for Nuclear Physics, said in a statement issued by Fermilab. The results are also being published in a set of papers submitted to Physical Review Letters, Physical Review A, Physical Review D and Physical Review Accelerators and Beams.

“The measurements have about one chance in 40,000 of being a fluke, the scientists reported, well short of the gold standard needed to claim an official discovery by physics standards. Promising signals disappear all the time in science, but more data are on the way. Wednesday’s results represent only 6 percent of the total data the muon experiment is expected to garner in the coming years.

 

“For decades, physicists have relied on and have been bound by the Standard Model, which successfully explains the results of high-energy particle experiments in places like CERN’s Large Hadron Collider. But the model leaves many deep questions about the universe unanswered.

“Most physicists believe that a rich trove of new physics waits to be found, if only they could see deeper and further. The additional data from the Fermilab experiment could provide a major boost to scientists eager to build the next generation of expensive particle accelerators.

“It might also lead in time to explanations for the kinds of cosmic mysteries that have long preoccupied our lonely species. What exactly is dark matter, the unseen stuff that astronomers say makes up one-quarter of the universe by mass? Indeed, why is there matter in the universe at all?...” (Dennis Overbye, New York Times).