It is one of the greatest mysteries of physics and cosmology: why, when the Big Bang is supposed to have produced equal amounts of matter and antimatter, did the two not annihilate each other, leaving nothing to form the Universe?

An experiment in the United States has now turned up a clue that could help to explain why planets, stars and people are made of matter — and indeed why they exist at all.

Physicists using the Tevatron atom-smasher at Fermilab near Chicago, including several British researchers, have found evidence that more matter than antimatter is created by high-energy particle collisions. Though the imbalance is only about 1 per cent, it could be sufficient to account for matter’s dominance in the Universe.

If the findings are confirmed, they would offer important insights into the physical phenomena soon after the Big Bang that allowed some matter to escape destruction. It also challenges aspects of the Standard Model of physics, which does not predict an overabundance of matter at the levels observed at the Tevatron.


Stefan Söldner-Rembold, of the University of Manchester, who is a co-leader of the DZero experiment that found the imbalance, said: “Many of us felt goose bumps when we saw the result. We knew we were seeing something beyond what we have seen before and beyond what current theories can explain.”

He said that the research will have implications for experiments at the Large Hadron Collider at CERN in Switzerland, which will study antimatter at higher energies than the Tevatron can reach. “If this is confirmed, there is a very good chance that the LHC will see exciting new physics quite early on,” Dr Söldner-Rembold said.

Orthodox theories hold that equal amounts of matter and antimatter should have been created at the Big Bang, but also that these should have cancelled each other out. For the Universe to have formed as it is, more matter must have been created, or some antimatter must have decayed without destroying matter. Previous observations have found some differences of this sort, but not at levels to explain the observed Universe.

“We have known about small imbalances for a generation but the effect is not strong enough to explain matter’s dominance in the Universe,” Dr Söldner-Rembold said. “What we think we have seen is a much bigger imbalance.”

The results have been submitted to the journal Physical Review D, and still require confirmation. They suggest that particles called B mesons, which fluctuate between matter and antimatter states, may spend more time as matter than as antimatter.

“The B mesons may stay in one state for longer than in the other, and that might explain the imbalance,” Dr SöldnerRembold said. “However, there could be other physics involved.”

Joe Lykken, of Fermilab, told The New York Times: “I would not say that this announcement is the equivalent of seeing the face of God, but it might turn out to be the toe of God.”

Matter and antimatter

Matter is made up of protons, which carry a postive electric charge, electrons with a negative charge and neutrons with no charge. Antimatter is made up of antiprotons (protons with a negative charge), positrons (an electron with a positive charge) and antineutrons

Luis Dias wrote:I thought this kind of thing was already mainstream years ago. At least it was the general idea of why matter was prevalent like a decade ago.