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A Chevalley scheme in
algebraic geometry Algebraic geometry is a branch of mathematics, classically studying zeros of multivariate polynomials. Modern algebraic geometry is based on the use of abstract algebraic techniques, mainly from commutative algebra, for solving geometrical ...
was a precursor notion of
scheme theory In mathematics, a scheme is a mathematical structure that enlarges the notion of algebraic variety in several ways, such as taking account of multiplicities (the equations ''x'' = 0 and ''x''2 = 0 define the same algebraic variety but different sc ...
. Let ''X'' be a separated integral
noetherian scheme In algebraic geometry, a noetherian scheme is a scheme that admits a finite covering by open affine subsets \operatorname A_i, A_i noetherian rings. More generally, a scheme is locally noetherian if it is covered by spectra of noetherian rings. Thus ...
, ''R'' its function field. If we denote by X' the set of subrings \mathcal O_x of ''R'', where ''x'' runs through ''X'' (when X=\mathrm(A), we denote X' by L(A)), X' verifies the following three properties * For each M\in X' , ''R'' is the field of fractions of ''M''. * There is a finite set of noetherian subrings A_i of ''R'' so that X'=\cup_i L(A_i) and that, for each pair of indices ''i,j'', the subring A_ of ''R'' generated by A_i \cup A_j is an A_i-algebra of finite type. * If M\subseteq N in X' are such that the maximal ideal of ''M'' is contained in that of ''N'', then ''M=N''. Originally, Chevalley also supposed that R was an extension of finite type of a field K and that the A_i 's were algebras of finite type over a field too (this simplifies the second condition above).


Bibliography


Online
{{Webarchive, url=https://web.archive.org/web/20160306015028/http://numdam.org/numdam-bin/feuilleter?id=pmihes_1960__4_ , date=2016-03-06 Scheme theory