identity element
121Orthogonal group — Group theory Group theory …
122Banach algebra — In mathematics, especially functional analysis, a Banach algebra, named after Stefan Banach, is an associative algebra A over the real or complex numbers which at the same time is also a Banach space. The algebra multiplication and the Banach… …
123Glossary of group theory — A group ( G , •) is a set G closed under a binary operation • satisfying the following 3 axioms:* Associativity : For all a , b and c in G , ( a • b ) • c = a • ( b • c ). * Identity element : There exists an e ∈ G such that for all a in G , e •… …
124Gelfand representation — In mathematics, the Gelfand representation in functional analysis (named after I. M. Gelfand) has two related meanings:* a way of representing commutative Banach algebras as algebras of continuous functions; * the fact that for commutative C*… …
125Order (group theory) — This article is about order in group theory. For order in other branches of mathematics, see Order (mathematics). For order in other disciplines, see Order. In group theory, a branch of mathematics, the term order is used in two closely related… …
126Laws of Form — (hereinafter LoF ) is a book by G. Spencer Brown, published in 1969, that straddles the boundary between mathematics and of philosophy. LoF describes three distinct logical systems: * The primary arithmetic (described in Chapter 4), whose models… …
127Dihedral group of order 6 — The smallest non abelian group has 6 elements. It is a dihedral group with notation D3 (or D6, both are used) and the symmetric group of degree 3, with notation S3. This page illustrates many group concepts using this group as example. Contents 1 …
128Torsion-free abelian groups of rank 1 — Infinitely generated abelian groups have very complex structure and are far less well understood than finitely generated abelian groups. Even torsion free abelian groups are vastly more varied in their characteristics than vector spaces. Torsion… …
