Irvine : Physicist to Test for 5th Force in Universe

The question at UC Irvine is a scientific one: Is there, indeed, a fifth force in the universe? Riley D. Newman, a physicist at UCI, has scheduled a set of experiments this fall to look for a force that, if real, tends to repel objects and to oppose the force of gravity at short distances.

Physicists heretofore have established the existence of only four forces operating in the universe. Those forces are gravity, electromagnetism, the “strong force” and the “weak force.” The so-called strong force binds particles together in the core of atoms, and the weak force plays a role in radioactive decay.

According to a UCI statement: “Efforts to detect (a) fifth force have been inconclusive. . . . Observations of the motions of planets and data from satellites show that, unlike gravity, the theorized (fifth) force does not produce significant effects over long distances.”

Newman’s experiments this fall will involve use of an electric eye that can detect movement less than a millionth the thickness of a sheet of paper.

“The outcome of Newman’s experiment to detect the fifth force . . . remains important whether or not the new force exists,” the statement said. “A negative result would restore physicists’ confidence in the value they have assigned to the gravitational constant . . . .”