New Theory of the Universe Marries Two of its Biggest Mysteries

New Theory of the Universe Marries Two of its Biggest Mysteries:

Physicists have devised a theory that unifies two widely studied mysteries of the universe: why there is an imbalance between regular matter and anti-matter (scientists expect to see equal amounts of each, but observe less anti-matter), and the identity of “dark matter” – the enigmatic particles thought to account for the extra gravitational pull observed in distant galaxies.


“We propose that at some point in the very early universe, dark matter interacted with regular matter in a particular way so as to shift the balance between matter and anti-matter ever so slightly towards matter, a process known as baryogenesis,” said Jeff Jones, a University of California-Santa Cruz physicist involved in the work, to PhysOrg.com. “We have proposed a new mechanism for baryogenesis that ties together these two mysteries, which are usually assumed to be unrelated.”

The prefix “baryo” in baryogenesis comes from “baryon,” a class of particles made of three quarks. Protons and neutrons are the most common examples of baryons. By extension, ordinary matter – atoms, in other words, which are primarily protons and neutrons – is therefore essentially made of baryons. Similarly, anti-matter is mostly anti-baryons.

The Russian physicist Andrei Sakharov, father of the Russian hydrogen bomb and advocate of peaceful coexistence between the Soviet and western systems, pointed out in the 1960s that in order for baryogenesis to take place there had to be a violation of CP symmetry.” CP symmetry is a physics concept stating that if ordinary particles are replaced by anti-particles in any physical process, and the particles' “handedness” is simultaneously reversed (sort of like how I'm right-handed but my mirror image, my “anti-self,” is a lefty), the result should be an equally feasible process occurring at the same rate as the first. Of the four known fundamental forces – strong, weak, electromagnetic, and gravity – scientists have only seen the weak force violate CP symmetry in experiments. However, when that violation results in the production of baryons, it also always generates anti-baryons. So there is no imbalance produced.

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