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In [[mathematics]], '''homogeneous''' has a variety of meanings.
In [[mathematics]], '''homogeneous''' may refer to:


* a [[homogeneous polynomial]], in algebra
*In [[algebra]], a [[homogeneous polynomial]] is a [[polynomial]] whose terms are [[monomial]]s all having the same total [[degree (mathematics)|degree]]; or are elements of the same dimension.
* a [[homogeneous function]]
* A [[homogeneous function]] is a function ''f'' satisfying ''f''(&alpha;''v'') = &alpha;<sup>''k''</sup>''f''(''v'') for some value of ''k''.
* a homogeneous [[differential equation]]
* A homogeneous [[differential equation]] is usually one of the form ''Lf'' = 0, where ''L'' is a [[differential operator]], the corresponding inhomogeneous equation being ''Lf'' = ''g'' with ''g'' a given function; the word ''homogeneous'' is also used of equations in the form ''Dy'' = ''f''(''y''/''x'').
* In [[linear algebra]] a '''homogeneous system''' is a one of the form A'''x'''='''0'''.
* a homogeneous [[system of linear equations]], in linear algebra
* [[homogeneous coordinates]]
* Homogeneous [[homogeneous coordinates | coordinates]] enable [[affine transformations]], such as spatial [[translation (geometry) | translations]], to be treated the same as [[linear transformations]] and thus represented by [[matrix (mathematics) | matrices]].
* a homogeneous [[number]]
* Homogeneous [[number]]s share identical prime factors (may be repeated).
* A [[homogeneous space]] for a [[Lie group]] G, or more general [[transformation group]], is a space X on which G acts transitively and continuously. Equivalently, a homogeneous space is a coset space G/H where H is a closed subgroup.
* a [[homogeneous space]] for a Lie group G, or more general transformation group
* a [[homogeneous ideal]] in a graded ring
** As a special case of the previous meaning, a [[manifold]] is said to be '''homogeneous''' for its [[homeomorphism]] group, or [[diffeomorphism]] group, if that group [[group action | acts]] transitively on it; this is true for [[connected space | connected]] manifolds without boundary.
* Given a colouring of the edges of a [[complete graph]], the term homogeneous applies to a subset of vertices such that all edges connecting two of the subset have the same colour; and in much greater generality in [[Ramsey theory]] for colourings of k-element subsets.
** This is also the notion of homogeneity used in (combinatorial) [[set theory]]: given a function ''f'':[X]<SUP>&alpha;</SUP>&rarr;''C'' colouring the set of subsets of ''X'' of order type &alpha; with colours from ''C'', a subset ''H'' of ''X'' is called homogeneous for ''f'' if all elements of [''H'']<SUP>&alpha;</SUP> get the same colour by ''f''.
*In a [[graded ring]], there is a concept of [[homogeneous ideal]], important in [[algebraic geometry]]


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[[Category:Mathematical terminology]]
[[Category:Mathematical terminology]]

Revision as of 01:34, 9 April 2006

In mathematics, homogeneous may refer to: