Generating set of a topological algebra

Generating set of a topological algebra

A generating set "S" of a topological algebra (e.g., a Banach algebra) "A" is a subset of "A" such that the smallest closed subalgebra of "A" containing "S" is "A" itself.

Since polynomials are dense in the set C [0,1] of continuous functions on the interval [0,1] ,the set {x} (and any of its supersets) consisting of the function xmapsto x is a generating set of the "Banach algebra" C [0,1] . However, it is not a generating set of the "algebra" C [0,1] (since in the definition of a generating set of an algebra the word "closed" is omitted).

A generating set is sometimes called a system of generators.

A structure (e.g., a topological algebra) "A" is called n-generated if there exists a generating set of "A" consisting of at most n elements. If "A" is n-generated for some finite n (resp., for n=1), then "A" is called finitely generated (resp., singly generated).


Wikimedia Foundation. 2010.

Игры ⚽ Нужно сделать НИР?

Look at other dictionaries:

  • Generating set — In mathematics, the expressions generator, generate, generated by and generating set can have several closely related technical meanings: * Generating set of an algebra: If A is a ring and B is an A algebra, then S generates B if the only sub A… …   Wikipedia

  • Borel set — In mathematics, a Borel set is any set in a topological space that can be formed from open sets (or, equivalently, from closed sets) through the operations of countable union, countable intersection, and relative complement. Borel sets are named… …   Wikipedia

  • Free Boolean algebra — In abstract algebra, a branch of mathematics, a free Boolean algebra is a Boolean algebra 〈 B , F 〉, such that the set B (called the carrier ) has a subset whose elements are called generators. The generators satisfy the following properties:… …   Wikipedia

  • Complete Boolean algebra — This article is about a type of mathematical structure. For complete sets of Boolean operators, see Functional completeness. In mathematics, a complete Boolean algebra is a Boolean algebra in which every subset has a supremum (least upper bound) …   Wikipedia

  • Basis (linear algebra) — Basis vector redirects here. For basis vector in the context of crystals, see crystal structure. For a more general concept in physics, see frame of reference. In linear algebra, a basis is a set of linearly independent vectors that, in a linear… …   Wikipedia

  • Borel algebra — In mathematics, the Borel algebra (or Borel sigma; algebra) on a topological space X is a sigma; algebra of subsets of X associated with the topology of X . In the mathematics literature, there are at least two nonequivalent definitions of this… …   Wikipedia

  • Differentiable manifold — A nondifferentiable atlas of charts for the globe. The results of calculus may not be compatible between charts if the atlas is not differentiable. In the middle chart the Tropic of Cancer is a smooth curve, whereas in the first it has a sharp… …   Wikipedia

  • Stallings theorem about ends of groups — In the mathematical subject of group theory, the Stallings theorem about ends of groups states that a finitely generated group G has more than one end if and only if the group G admits a nontrivial decomposition as an amalgamated free product or… …   Wikipedia

  • Grushko theorem — In the mathematical subject of group theory, the Grushko theorem or the Grushko Neumann theorem is a theorem stating that the rank (that is, the smallest cardinality of a generating set) of a free product of two groups is equal to the sum of the… …   Wikipedia

  • Nielsen transformation — In mathematics, especially in the area of abstract algebra known as combinatorial group theory, Nielsen transformations, named after Jakob Nielsen, are certain automorphisms of a free group which are a non commutative analogue of row reduction… …   Wikipedia

Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”