The long arms of the law.

GRAVITY; GEOPHYSICS; GRAVITATIONAL fields; METAPHYSICAL cosmology; ASTRONOMY; RELATIVITY (Physics)

This article focuses on a controversial theory called modified Newtonian dynamics (MOND). Newtonian law of gravity is the basis for many cosmological theories and physical laws. But some scientists believe that this law is wrong. It's a long-standing debate whether Newtonian law of gravity might actually be flawed. That is the claim of a growing number of physicists who support MOND. The theory has recently overcome some serious problems that had plagued it since its inception--such as how it fits with general relativity. If MOND is correct, it will pull the rug out from under the established view of gravity and dark matter, which together underpin almost everything known about astronomy. INSET: A good MOND is hard to find.