Preliminary results from two experiments suggest that something may be wrong with the way physicists believe the universe works, a perspective that has both the field of particle physics as confused and excited.
Tiny particles called muons do not do exactly what is expected of them in two different long-term experiments in the United States and Europe. The confusing results – if proven correct – reveal major problems with the rule books that physicists use to describe and understand how the universe works at the subatomic level.
“We think we might be swimming in a sea of background particles all the time that were not directly discovered,” Chris Polly, a scientist with the Fermilab experiment, told a news conference. “There may be monsters that we have not yet imagined coming out of the vacuum that interact with our muons, and this gives us a window to see them.”
The rules manual, called the Standard Model, was developed about 50 years ago. Experiments over the decades have stated countless times that his descriptions of the particles and forces that make up and govern the universe were quite important. So far.
“New particles, new physics could be just beyond our research,” said Alexey Petrov, a particle physicist at Wayne State University. “It’s tempting.”
The U.S. Department of Energy’s Fermilab on Wednesday announced results in 8.2 billion races along a runway outside of Chicago, which, while many people smile at physicists: muon’s magnetic fields don’t seem to be what they used to be. should be the standard model. This follows the new results published last month from the Large Hadron Collider of the European Center for Nuclear Research, which found a surprising proportion of particles from high-speed collisions.
If confirmed, the US results would be the largest discovery in the bizarre world of subatomic particles in nearly 10 years since the discovery of the Higgs boson, often called the “particle of God,” said Aida El-Khadra of the University of Illinois. working on theoretical physics for the Fermilab experiment.
The purpose of the experiments, explains Johns Hopkins University theoretical physicist David Kaplan, is to remove particles and find out if “something funny” is happening to both the particles and the seemingly empty space between them.
“Secrets do not live only in matter. They live in something that seems to fill all space and time. These are quantum fields, “Kaplan said. “We put energy into the vacuum and see what comes out.”
Both sets of results involve a strange, transient particle called a muon. The muon is the heaviest cousin with the electron orbiting the center of an atom. But the muon is not part of the atom, it is unstable and normally exists only for two microseconds. After being discovered in cosmic rays in 1936, it confused scientists so much that a famous physicist asked, “Who ordered this?”
“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 top scientists in the US Fermilab experiment called Muon g-2.
The experiment sends muons around a magnetized track that keeps the particles in place long enough for researchers to look at them more closely. Preliminary results suggest that the magnetic “rotation” of the muons is 0.1 percent of what the standard model predicts. This may not sound like much, but for particle physicists it’s huge – more than enough to understand the current understanding.
Researchers need another year or two to complete the analysis of the results of all laps around the 14-meter track. If the results do not change, they will be considered a major breakthrough, Venanzoni said.
Separately, at the world’s largest atomic destroyer at CERN, physicists crashed protons against each other to see what happened next. One of several separate experiments of particle colliders measures what happens when particles called beauty or bottom quarks collide.
The standard model predicts that these beauty quark accidents should lead to an equal number of electrons and muons. It’s a way to toss a coin 1,000 times and get an equal number of heads and tails, said Chris Parkes, head of the big 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% difference, with significantly more electrons than muons, said experiment researcher Sheldon Stone of Syracuse University.
No experiment has yet been called an official discovery, as there is still little chance that the results will be statistically strange. Conducting experiments several times – planned in both cases – could, in a year or two, meet the incredibly stringent statistical requirements for physics to call it a discovery, the researchers said.
If the results are maintained, they would return “any other calculation made” to the world of particle physics, Kaplan said.
“It’s not a fudge. There is something wrong, “Kaplan said. This could be explained by a new particle or force.
Or these results may be mistakes. In 2011, a strange discovery that a particle called a neutrino appeared to travel faster than light threatened the model, but it turned out to be the result of a weak electrical connection problem in the experiment.
“We checked all our cable connections and did everything we could to verify our data,” Stone said. “We’re a little confident, but you never know.”