prime subfield
61Cyclotomic unit — In mathematics, a cyclotomic unit is a unit of an algebraic number field of the form (ζn − 1)/(ζ − 1) for ζ a root of unity, or more generally a unit that can be written as a product of these and a root of unity. The… …
62political economy — political economist. 1. a social science dealing with political policies and economic processes, their interrelations, and their influence on social institutions. 2. (in the 17th 18th centuries) the art of management of communities, esp. as… …
63Earth Sciences — ▪ 2009 Introduction Geology and Geochemistry The theme of the 33rd International Geological Congress, which was held in Norway in August 2008, was “Earth System Science: Foundation for Sustainable Development.” It was attended by nearly… …
