basic fact
81Quadratic residue — In number theory, an integer q is called a quadratic residue modulo n if it is congruent to a perfect square modulo n; i.e., if there exists an integer x such that: Otherwise, q is called a quadratic nonresidue modulo n. Originally an abstract… …
82Colleen Peterson — Birth name Colleen Susan Peterson Born November 14, 1950 Origin Peterborough, Ontario, Canada Died October 9, 1996(1996 10 09) (aged 45) …
83Twelve Colonies — United Colonies of Kobol Battlestar Galactica country Anthem Colonial Anthem Source Battlestar Galactica, Caprica Creator Glen A. Larson (1978 series) Ronald D. Moore (2003 series) Genre …
84The Fabric of Reality — is a 1997 book by physicist David Deutsch, which expands upon his views of quantum mechanics and its meanings for understanding reality.This interpretation, or what he calls the multiverse hypothesis, is one strand of a four strand theory of… …
85Carlo Amoretti — was an erudite ecclesiastic, scholar, writer, and scientist. His life straddled the 18th and 19th centuries. He was born on 16 March 1741 in Oneglia, now Imperia in the Liguria region, Italy and died on 23 March 1816.He entered the Augustinian… …
86Criticisms of Marxism — This article is about criticisms of Marxism, a branch of socialism. For criticisms of socialism in general, see Criticisms of socialism. See also Criticisms of Communist party rule for a discussion on specific criticisms of Communist states. Part …
87Penn effect — The Penn effect is the economic finding that real income ratios between high and low income countries are systematically exaggerated by GDP conversion at market exchange rates. It has been a consistent econometric result for at least fifty years …
88Skeleton (category theory) — In mathematics, a skeleton of a category is a subcategory which, roughly speaking, does not contain any extraneous isomorphisms. In a certain sense, the skeleton of a category is the smallest equivalent category which captures all categorical… …
89Homological algebra — is the branch of mathematics which studies homology in a general algebraic setting. It is a relatively young discipline, whose origins can be traced to investigations in combinatorial topology (a precursor to algebraic topology) and abstract… …
90Ultralimit — For the direct limit of a sequence of ultrapowers, see Ultraproduct. In mathematics, an ultralimit is a geometric construction that assigns to a sequence of metric spaces Xn a limiting metric space. The notion of an ultralimit captures the… …
