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An equidimensional scheme (or, pure dimensional scheme) is a scheme all of whose irreducible components are of the same dimension (implicitly assuming the dimensions are all well-defined). Examples [ edit ]
In mathematics, specifically algebraic geometry, a scheme is a 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 schemes) and allowing "varieties" defined over any commutative ring (for example, Fermat curves are defined over the integers).
By definition, a morphism of schemes is just a morphism of locally ringed spaces. Isomorphisms are defined accordingly. A scheme, by definition, has open affine charts and thus a morphism of schemes can also be described in terms of such charts (compare the definition of morphism of varieties). [1] Let ƒ:X→Y be a morphism of schemes.
The codes given in the chart below usually tell the length and width of the components in tenths of millimeters or hundredths of inches. For example, a metric 2520 component is 2.5 mm by 2.0 mm which corresponds roughly to 0.10 inches by 0.08 inches (hence, imperial size is 1008).
They can also have irreducible components of unexpectedly high dimension. For example, one might expect the Hilbert scheme of d points (more precisely dimension 0, length d subschemes) of a scheme of dimension n to have dimension dn, but if n ≥ 3 its irreducible components can have much larger dimension.
Taxonymy (not to be confused with, though related to, taxonomy) is a sub-variety of hyponymy.Within the structure of a taxonomic lexical hierarchy, two types of hyponymic relation may be distinguished: the first—exemplified in "An X is a Y"—corresponds to so-called "simple" hyponymy; the second—that which is exemplified in "An X is a kind/type of Y"—is more discriminating, and ...
In category theory, a branch of mathematics, the opposite category or dual category C op of a given category C is formed by reversing the morphisms, i.e. interchanging the source and target of each morphism. Doing the reversal twice yields the original category, so the opposite of an opposite category is the original category itself.