Preliminary results from two experiments suggest that something might be wrong with the basic way physicists think the universe works, a perspective that has the field of particle physics baffled and excited.
Small particles called muons do not quite do what is expected of them in two long-term experiments in the United States and Europe. The confusing results, if proven correct, reveal important problems with the rulebooks that physicists use to describe and understand how the universe works at the subatomic level.
“We think we could be swimming in a sea of bottom particles all the time that haven’t been discovered directly,” Fermilab co-head scientist Chris Polly told a news conference. “There may be monsters that we still didn’t imagine emerging from the void interacting with our muons and that gives us a chance to see them.”
The rulebook, called the Standard Model, was developed about 50 years ago. Experiments conducted for decades repeatedly claimed that their descriptions of the particles and forces that form and govern the universe were virtually important. Bye now.
“New particles, new physics could be beyond our research,” said Alexey Petrov, a particle physicist at Wayne State University. “It’s tempting.”
U.S. Department of Energy Fermilab on Wednesday announced results of 8.2 billion races along a track outside of Chicago that, while they do for most people, physicists worry : the magnetic fields of the muons do not appear to be what the standard model says. This follows the new results published last month by the Large Hadron Collider of the European Nuclear Research Center which found a surprising proportion of particles after high-speed collisions.
If confirmed, American results would be the largest find in the bizarre world of subatomic particles in nearly ten years, since the discovery of the Higgs boson, often called the “particle of God,” said Aida El-Khadra. from the University of Illinois, who is working on theoretical physics for the Fermilab experiment.
The head of the experiments, explains Johns Hopkins University theoretical physicist David Kaplan, is to separate particles and find out if there is “something fun” with the particles and the seemingly empty space between them.
“Secrets don’t just live in matter. They live in something that seems to fill all the space and time. They are quantum fields, ”Kaplan said. “We’re putting energy in the vacuum and see what comes out.”
Both sets of results involve the strange and fleeting particle called the muon. The muon is the heaviest cousin of the electron orbiting the center of an atom. But the muon is not part of the atom, is unstable and usually only exists for two microseconds. After being discovered with cosmic rays in 1936, he confused scientists so that a famous physicist asked, “Who ordered it?”
“From the beginning it made physicists scratch their heads,” said Graziano Venanzoni, an experimental physicist at an Italian national laboratory who is one of the leading scientists in the American Fermilab experiment, called Muon g-2 .
The experiment sends muons around a magnetized track that keeps the particles in existence long enough for researchers to see them up close. Preliminary results suggest that the magnetic “rotation” of the muons is 0.1% of what the standard model predicts. This may not sound like much, but for particle physicists it is huge, more than enough to perfect current understanding.
Researchers need a year or two to finish analyzing the results of all laps around the 14-meter track. If the results do not change, it will be considered an important discovery, Venanzoni said.
Besides, at the world’s largest atomic destruction center, CERN, physicists have crashed protons against each other to see what happens next. One of several separate experiments on particle colliders measures what happens when particles called beauty or background quarks collide.
The standard model predicts that these beauty quark accidents should result in an equal number of electrons and muons. It’s like tossing a coin 1,000 times and getting an equal number of heads and tails, said Chris Parkes, head of the Great Hadron Collider’s beauty experiment.
But that’s not what happened.
The researchers analyzed data from several years and several thousand accidents and found a 15 percent difference, with a significant number of electrons larger than muons, said experiment researcher Sheldon Stone of Syracuse University.
Neither experiment is yet called an official discovery because there is still a small probability that the results are statistical peculiarities. Running the experiments more often, predicted in both cases, could lead, in a year or two, to incredibly strict statistical requirements for physics to consider it a discovery, the researchers said.
If the results were maintained, they would mean “all the other calculations done” in the world of particle physics, Kaplan said.
“It’s not a fudge factor. That doesn’t happen, ”Kaplan said. That something could be explained with a new particle or force.
Or these results can be mistakes. In 2011, a strange finding that it appeared that a particle called a neutrino appeared to travel faster than light threatened the model, but turned out to be the result of a weak electrical connection problem in the experiment.
“We checked all the cable connections and did our best to check our data,” Stone said. “We’re confident, but you never know.”