Gravity tugs at the center of a priority battle, Science News Online (12/18/99)

 Gravity tugs at the center of a priority battle

 By I. Peterson

 CAMBRIDGE, England, July 1686 - A bitter dispute over who came up with a 
fundamental rule of gravity threatens the publication of a sweeping new theory 
on the nature of planetary motion.

 The theory at issue is the work of Isaac Newton of Trinity College in 
Cambridge, already known and highly respected for his research in optics and 
mathematics. Newton proposes a law of gravity based on the idea that bodies 
attract each other in proportion to their masses and inversely as the square of 
the distance separating them. Doubling the distance between two celestial 
bodies, for instance, would reduce the gravitational force between them to 
one-quarter of its previous value.

 Newton's forthcoming book, Philosophiae Naturalis Principia Mathematica, 
explains how his theory accounts for the elliptical orbits of planets, the 
motion of comets, the occurrence of tides, and a variety of other phenomena.

 It's an "incomparable treatise," says Edmond Halley, clerk to the Royal 
Society for the Improvement of Natural Knowledge in London, who is in charge of 
publishing Newton's book and has studied the first two parts of the manuscript.

 Now, Robert Hooke, secretary to the Royal Society, contends that Newton did 
not himself invent the notion that an inverse-square force law governs 
planetary motion. "Newton stole the idea from me," he insists.

 Hooke says that he had written to Newton about planetary and projectile motion 
in 1679, after developing his own "system of the world" to explain natural 
phenomena. He admits, however, that he was unable to master the mathematics 
required to show how elliptical orbits arise from an inverse-square law.

 Acknowledging that Newton had succeeded in solving the mathematical problem 
but incensed that his own name is not mentioned in a section of Newton's 
treatise recently read at a Royal Society meeting, Hooke has demanded that 
Newton give him proper credit in the Principia for the inverse-square law.

 According to Halley, however, Newton insists that he himself had discovered 
the inverse-square law during his studies of planetary motion. Unlike Hooke, 
Newton had not come upon it by accident, Halley says.

 In the latest development, Newton appears to have gone through the existing 
manuscript to delete Hooke's name from any pages in which it had been 
mentioned. He has also informed Halley by letter that he intends to suppress 
the third part of the Principia.

"Philosophy [science] is such an impertinently litigious lady that a man had as 
good be engaged in law suits as have to do with her," Newton wrote. Clashes 
with Hooke over scientific matters on two previous occasions appear to rankle 
him still.

 Newton's threat to withhold a critical portion of his highly anticipated book 
comes as a great shock to Halley. A few weeks ago, the Royal Society's council 
had approved Halley's plan to publish all three books of the Principia. Because 
of its own financial difficulties, stemming from the commercial failure of an 
elaborate book on the history of fishes, the society had made Halley personally 
responsible for funding Newton's publication.

 Hooke's claims are "outrageous," says Christopher Wren, former professor of 
astronomy at the University of Oxford. "The consensus at the society-and in the 
coffeehouses-is that Hooke is making a fool of himself."

 There is a great distance between a truth that is merely glimpsed and a truth 
that is truly demonstrated, he adds.

 If Newton's book is published, it may prove hard going for most readers. 
Newton has boasted privately to a friend that he has deliberately made the 
Principia as unreadable as possible "to avoid being bated by little smatterers 
in mathematics."

"It's a tough book to dip into," says a critic who has seen portions of the 
manuscript. "Only experts will be comfortable with it."

"Not even the author could possibly understand it," adds a Cambridge student.

 Halley sees it differently. "It's an epoch-making book," he says. "Newton 
unifies the disparate theories of Galileo and Kepler into a single, coherent, 
mathematically and experimentally supported whole."

 Halley is cautiously optimistic that once the storm blows itself out, Newton 
will continue preparing the Principia for publication.

 If it's completed and printed, Halley says, "the world will pride itself to 
have a subject capable of penetrating so far into the abstrusest secrets of 
nature and exalting human reason to so sublime a pitch by this utmost effort of 
the mind."