Number 206 (Story #3), December 8, 1994 by Phillip F. Schewe and Ben Stein EINSTEIN'S GENERAL THEORY OF RELATIVITY does not fit well with quantum mechanics, but it does persist as the prevailing theory of gravity and has been vindicated in many experimental tests. Nevertheless, scientists try to build a better theory or at least to find flaws in Einstein's equations. Two researchers, Huseyin Yilmaz of Tufts University and Carroll Alley of the University of Maryland (301-405-6098), believe they have discovered a case in which general relativity provides a nonsensical result, namely that the gravitational attraction between two infinitely wide (but thin) parallel plates in close proximity would be zero. Furthermore, they propose a gravity theory of their own, one which, they claim, is compatible with quantum mechanics. Other relativity experts, such as Clifford Will of Washington University (314-935- 6244) and William Unruh of the University of British Columbia, dispute Yilmaz's assertions and claim that general relativity is in good health. Yilmaz and Alley hope to use small unexplained discrepancies in the performance of the Global Positioning System (the satellite-based navigation network) and new tests involving the travel times of laser beams over different paths to test their theory. (Science News, 3 December 1994.)