Fred Ullrich / Fermilab
Confidence is growing in results from a particle physics experiment at the Tevatron collider that may help explain why the universe is full of matter.
Why are we here? It remains one of the largest unexplained mysteries of the universe, but particle physicists are gaining more confidence in a result from an atom smashing experiment that could be a step toward providing an answer.
We exist because the universe is full of matter and not the opposite, so-called antimatter. When the Big Bang occurred, equal parts of both should have been created and immediately annihilated each other, leaving nothing leftover to build the stars, planets and us.
Thankfully, it didn't happen that way. There's an asymmetry between matter and antimatter. Why this is remains inadequately explained, Stefan Soldner-Rembold, a co-spokesman for the particle physics experiment at the Fermi National Accelerator Laboratory outside of Chicago, told me on Thursday.
"We are looking for a larger asymmetry than we currently know in the best theories in physics, which is called the standard model," said Soldner-Rembold, who is based at the University of Manchester in England.
Using the Fermilab's Tevatron collider, members of the DZero experiment are smashing together protons and their antiparticle, called antiprotons, which are perfectly symmetric in terms of matter and antimatter, he explained.
"So you expect what comes out will also be symmetric in terms of matter and antimatter," he said. "But what we observe is that there is a slight, on the order of 1 percent, asymmetry where more matter particles are produced than antiparticles."
This 1 percent asymmetry is larger than predicted by the standard model and thus helps explain why there is more matter than antimatter in the universe.
The DZero team announced this finding of asymmetry in 2010, but their confidence in the result wasn't sufficient to call it a discovery. At that point, there was a 0.07 chance the result was due to a random fluctuation in the data.
The team has now analyzed 1.5 times more data with a refined technique, increasing their confidence in the result. The probability that the asymmetry is due to a random fluctuation is now just 0.005 percent. They'd like to get to an uncertainty of less than 0.00005 percent before popping open the champagne.
The new results were presented Thursday at Fermilab.
"There are very high thresholds in physics so that people can really call something a discovery and be absolutely sure," Soldner-Rembold said. "We are going in the right direction."
Even more work at Fermilab and further, complementary experiments with the Large Hadron Collider in Geneva will be required to shore up confidence that what they are seeing really is real, and thus a step toward explaining why the universe has much more matter than antimatter.
"To really understand how the universe evolved is the next step," he said. "We do a particular process in the lab. In order to say is this enough to explain the amount of matter around us is not as easy as saying 1 percent sounds good."
And for those hoping that science has all the answers, Soldner-Rembold cautions that science will never answer the question of "why we are here, it only tries to understand the underlying laws of nature."
More on particle physics:
- That wily Higgs boson is running out of places to hide
- New subatomic particle: real or anomaly?
- Aging U.S. particle accelerator gets more time
- Seven smashing atom smashers
John Roach is a contributing writer for msnbc.com. Connect with the Cosmic Log community by hitting the "like" button on the Cosmic Log Facebook page or following msnbc.com's science editor, Alan Boyle, on Twitter (@b0yle).