The early Universe should have formed equal quantities of matter and antimatter, according to the laws of physics, as currently understood.
When matter and antimatter collide, they are each completely destroyed, converted into energy, or pairs of other particles. These two forms of particles and antiparticles would have annihilated each other, leaving almost nothing but energy throughout the Universe. Astrophysicists have long questioned how matter came to dominate every visible region in space, and determined that ordinary matter was slightly favored during the early Universe. The mechanism behind this asymmetry, however, remained unknown until this time.
University of California Los Angeles (UCLA) researchers believe they may have an answer explaining how matter came to dominate antimatter more than 13 billion years in the past.
A primordial soup of energy permeated the Universe in its distant past, before conditions cooled enough to allow for the creation of matter and antimatter.
The Higgs boson, a particle believed to provide matter with mass, may be behind this mysterious cosmological mystery. A moving Higgs field, associated with the particle, could have slightly affected masses of matter and antimatter, temporarily altering the balance between the varieties.
The asymmetry in the early Universe was tiny - just one part in 10 billion. After the annihilation of a vast majority of the particles in the early Universe, the scant remains formed every star, planet and galaxy around us.
The Higgs boson particle was first proposed 50 years ago, in order to balance certain physics equations. However, it was only discovered by researchers at the Large Hadron Collider in Switzerland in 2012. When the particle was discovered, the mass was found to not be consistent with either of the two major theories about the nature of the Cosmos as a whole. However, the mass could be explained if the Higgs field was larger in the early Universe than the modern "equilibrium value" observed by present-day astronomers.
This field "had to descend to the equilibrium, in a process of 'Higgs relaxation,'" Alexander Kusenko, physics and astronomy professor at UCLA , said.
The Higgs field is thought to permeate the entire Universe, passing through all matter, providing substance with its mass. In the modern day, particle pairs of matter and antimatter have identical masses, and opposite charges. If this was not the case in the early Universe, that imbalance could have resulted in the prevalence of matter over antimatter observed today.
Analysis of how the Higgs field could have created asymmetry in the early Universe, leading to the prevalence of matter in the modern day was published in the journal Physical Review Letters.
