Projective module

GPTKB entity

Statements (37)
Predicate Object
gptkbp:instanceOf Module theory concept
gptkbp:characterization A module is projective if and only if the functor Hom(P,-) is exact
gptkbp:citation Atiyah, M. F.; Macdonald, I. G. Introduction to Commutative Algebra
Lang, Serge. Algebra
Rotman, Joseph J. An Introduction to Homological Algebra
gptkbp:contrastsWith gptkb:Injective_module
Flat module
gptkbp:definedIn gptkb:King
gptkbp:defines A module P such that every surjective module homomorphism f:M→N and every module homomorphism g:P→N, there exists a module homomorphism h:P→M such that f∘h=g.
gptkbp:example gptkb:Finitely_generated_projective_module
gptkb:Free_module
Direct sum of free modules
gptkbp:field gptkb:Abstract_algebra
gptkb:Ring_theory
gptkbp:generalizes gptkb:geometry
Projective representation
gptkbp:hasProperty Lifting property
Splitting property
https://www.w3.org/2000/01/rdf-schema#label Projective module
gptkbp:namedFor Algebraists
gptkbp:property Direct summand of a free module
Every free module is projective
Every projective module is flat
Projective modules are closed under direct sums
Projective modules are closed under direct summands
gptkbp:relatedConcept Projective resolution
Projective cover
Projective dimension
gptkbp:used_in gptkb:Algebraic_topology
gptkb:Algebraic_geometry
gptkb:Representation_theory
Category theory
Homological algebra
gptkbp:bfsParent gptkb:Finitely_generated_projective_module
gptkb:Free_module
gptkb:Stably_free_module
gptkbp:bfsLayer 7