Stably free module

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In mathematics, a stably free module is a module which is close to being free.

Contents

Definition

A finitely generated module M over a ring R is stably free if there exist free finitely generated modules F and G over R such that

Properties

See also

Related Research Articles

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The Quillen–Suslin theorem, also known as Serre's problem or Serre's conjecture, is a theorem in commutative algebra concerning the relationship between free modules and projective modules over polynomial rings. In the geometric setting it is a statement about the triviality of vector bundles on affine space.

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In mathematics, the Artin–Rees lemma is a basic result about modules over a Noetherian ring, along with results such as the Hilbert basis theorem. It was proved in the 1950s in independent works by the mathematicians Emil Artin and David Rees; a special case was known to Oscar Zariski prior to their work.

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In algebra, a torsion-free module is a module over a ring such that zero is the only element annihilated by a regular element of the ring. In other words, a module is torsion free if its torsion submodule is reduced to its zero element.

In algebra, a free presentation of a module M over a commutative ring R is an exact sequence of R-modules:

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References

  1. Lang, Serge (1993), Algebra (Third ed.), Reading, Mass.: Addison-Wesley, ISBN   978-0-201-55540-0, Zbl   0848.13001
  2. Lam, T. Y. (1978). Serre's Conjecture. p. 23.