Arriving at that answer could reveal why we even exist, scientists say.
The Fermi National Accelerator Laboratory researchers say collisions of protons and anti-protons produce pairs of particles called muons more frequently than they produce anti-muons, The New York Times reported.
"This result may provide an important input for explaining the matter dominance in our universe," Guennadi Borissov, a co-leader of the study from England's Lancaster University, said Friday at the Fermi lab in Batavia, Ill.
Gustaaf Brooijmans of Columbia University, who is a member of the research team, says the world's largest and highest-energy particle accelerator near Geneva, Switzerland, will help move the research forward.
"This is something we should be able to poke at with the Large Hadron Collider," Brooijmans said.
Joe Lykken, a theorist at Fermilab, agrees the potential for a significant breakthrough in answering why we exist is great.
"So 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," Lykken told the Times.