The latter half of the 1980's has witnessed the experimental verification of two fundamentally quantum mechanical processes that promise to play an increasingly important role in fundamental physics and precision measurements. In 1985, researchers at AT&T Bell Laboratories made the first observation of squeezed light (more properly, squeezed vacuum fluctuations) using four wave mixing in an atomic beam of sodium atoms pumped by a dye laser light. And a year later, the first successful observation of Berry's geometrical phase - by researchers using an optical fiber - was presented. Measurement standards based on quantum mechanical effects are becoming increasingly common. Time and voltage standards are based on quantal processes, and the Quantum Hall effect promises to do the same for resistance. Therefore, the discovery of a new quantum mechanical effect is likely to generate great excitement. The identification of squeezed light and geometrical phases as possible intrinsic standards and aids in developing improved measurement methodologies motivates a brief introduction to the subjects. Indeed, it is only with a clearer understanding of the these newly proposed geometrical phases that we can begin to remove (exploit) their effects from (on) precision measurements.
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