SCIENCE

A new force in nature

JOHN BARBER January 20 1986
SCIENCE

A new force in nature

JOHN BARBER January 20 1986

A new force in nature

SCIENCE

Ever since Galileo reputedly dropped cannonballs from the Leaning Tower of Pisa, his theory that objects in a vacuum fall at the same rate regardless of their mass has been a cornerstone of science. Newton incorporated it into his laws of motion, as did Einstein when he revised those laws with his theory of relativity. But last week a group of scientists headed by Ephraim Fischbach of the University of Washington in Seattle reported the discovery of a force that pushes against gravity and causes some objects to drop faster than others in a vacuum.

Although Fischbach said that the force will fundamentally alter man’s conception of the universe, he avoided predicting that it will overthrow Einstein’s theory of relativity. But one Canadian researcher was more daring. Since 1979 University of Toronto physicist John Moffat has been collecting data to support his own theory of relativity—a fundamental challenge to Einstein.

One of the main differences between the Torontonian’s theory and Einstein’s is that Moffat predicts the existence of a fifth force exactly like the one described last week. After reading Fisch-

bach’s report in Physical Review Letters, Moffat told Maclean’s: “This could be one of the most important scientific discoveries of the century.” Fischbach’s so-called “hypercharge” is the fifth force of nature to be discovered (after gravity, electromagnetism, and the strong and weak forces that control subatomic structure). He discovered it by reanalysing data from an experiment reported in 1922 by Hungarian researcher Roland von Eötvös. In a test of Galileo’s law, Eötvös discovered minute gravitational discrepancies which he dismissed as insignificant. But Fischbach detected a pattern in the discrepancies that varied according to the atomic structure of the objects that Eötvös had weighed. In effect, Fischbach reported that in a vacuum a feather will fall

faster than a coin because hypercharge pushes against the coin more than against the feather.

In his theory of relativity, Moffat proposed the existence of a new subatomic particle that carries the fifth force. He called it a “skewon,” and theorized that the force alters gravity according to the number of skewons in the affected objects. By contrast, Einstein’s “principle of equivalence” accepted Galileo’s assertion that gravity affects all objects equally. Moffat has sought proof of the force in binary star systems, in which two stars orbit around each other. Relativity decrees that the orbits of planets and stars should shift minutely with each repetition. Last August a report on one binary star system, called DI Herculis, proved that its shifts contradicted Einstein’s theory of relativity. As well, they fitted Moffat’s exactly.

Fischbach said that the fifth force would not discredit Einstein and added that its effect was very small and local. But Moffat said that the enormous number of skewons in ^ stars would make the § force strong enough o to reshape Einstein’s o view of the universe. He added, “It may be a

small effect, but so

was Einstein’s.” Both scientists said, however, that the discovery of hypercharge will reshape current views of physics and that it may play a major role in formulating the long-sought “unified theory” showing how all known forces are part of a single general force.

Both scientists also said that until the Eötvös experiment is repeated using modern technology, the fifth force will remain a preliminary experimental result, not a fact. But 53-year-old Moffat, who is accustomed to his colleague’s skepticism, said: “It is not easy to do what I’m doing. It was not easy for Einstein either. He had a difficult time with his colleagues because he was overthrowing Newton.”

— JOHN BARBER in Toronto