Science: An Anti-Matter Universe?

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The anti-proton—atomic twin of the proton but with a negative rather than a positive charge—was once only a well-reasoned theory. Nuclear physicists knew the particle must exist, but not until last year did they lay hands on one, and then they had to create it themselves (TIME, Oct. 31 et seq.).

Since then, many scientists have wondered if all nature is as balanced between matter and antimatter as the atom is between positive and negative charges. If so, where are all the antiprotons to balance the protons that help make up the known universe? Writing in Science, Dr. Maurice Goldhaber, 45, senior physicist at Brookhaven National Laboratory, suggests a startling theory. Could it be, asks Scientist Goldhaber, that the missing antiprotons form a whole separate universe of antimatter?

The most popular theories of the origin of matter assume only the asymmetric creation of nucleons (protons and neutrons). But what about the creation of anti-nucleons (antiprotons and anti-neutrons)? To preserve symmetry, Goldhaber postulates that all matter—positive and negative—may be traced to an unstable, giant particle that he calls the "universon." At some dawn of time this particle split into a positively charged "cosmon" and a negatively charged "anti-cosmon," much like a fundamental particle, e.g., a heavy meson, disintegrating automatically into two oppositely charged particles. Energy released by the split shoved apart the cosmon and anti-cosmon at tremendous speeds.

After the split, the cosmon decayed into the known universe. "The anti-cosmon may or may not have decayed by now, since spontaneous decay is a process governed by a statistical law," says Goldhaber. "If it did decay (forming an 'anti-cosmos'), any anti-nucleons that are shot out with sufficient velocity to reach our cosmos will annihilate some part of it, possibly establishing a deviation from spherical symmetry in the distribution of matter in our cosmos."

But Goldhaber readily admits that no one has any evidence that an antimatter universe has ever so tampered with the known universe. In fact, man does not now have the evidence—or the tools—to prove or disprove the anti-universe theory. "This is not the kind of debate that is settled overnight," Goldhaber said last week as his fellow scientists began to grapple with his science-fictionlike hypothesis. "I'm only asking a question, not making a statement."