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Our Knowledge of G Gets Worse, Then Better

JUL 01, 2000

DOI: 10.1063/1.1292470

The precision with which we know a fundamental constant usually gets better with the passing years. Just the opposite, however, was happening recently to G, Newton’s gravitational constant. In 1987, CODATA, the international arbiter of metrology, was quoting an uncertainty of ±128 parts per million for G, the most poorly known of the fundamental constants. But then things got even worse. Several recent measurements have given values many standard deviations outside these limits, forcing CODATA to increase its assigned uncertainty to ±1500 ppm for the latest compilation.

This Content Appeared In
pt-cover_2000_07.jpeg

Volume 53, Number 7

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