Примеры использования Algebraic group на Английском языке и их переводы на Русский язык
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In fact, SI(n) is a simple algebraic group for n at least 2.
A reductive algebraic group over a local field has a BN-pair where B is an Iwahori subgroup.
The basic example of a non-reductive linear algebraic group is the additive group Ga over a field.
Every compact connected Lie group has a complexification,which is a complex reductive algebraic group.
Equivalently, a linear algebraic group over k is a smooth affine group scheme over k.
The simple group PSL(n, q) is not usually the same as the group PSL(n, Fq)of Fq-valued points of the algebraic group PSLn.
Also, k-forms of a given algebraic group G(sometimes called"twists" of G) are classified by H1k, AutG.
Authors differ on whether groups such as An(q) are the groups of pointswith values in the simple or the simply connected algebraic group.
In terms of category theory, an algebraic group is a group object in the category of algebraic varieties.
The identity component of PGL(2,R)(sometimes called PSL(2,R))is a real reductive group that cannot be viewed as an algebraic group.
With this definition, to the algebraic group G{\displaystyle\mathrm{G}} is associated a collection of"discrete" subgroups all commensurable to each other.
This differs slightly from the terminology for abstract groups, in that a simple algebraic group may have nontrivial center although the center must be finite.
A linear algebraic group over a field k is defined as a smooth closed subgroup scheme of GL(n) over k, for some positive integer n.
First, one can study the representations of a reductive group G over a field k as an algebraic group, which are actions of G on k-vector spaces.
The algebraic group O(q) has two connected components, and its identity component SO(q) is reductive, in fact simple for q of dimension n at least 3.
Every central simple algebra A over k determines a reductive group G SL(1,A),the kernel of the reduced norm on the group of units A* as an algebraic group over k.
For a k-simple algebraic group G, Tits's simplicity theorem says that the abstract group G(k) is close to being simple, under mild assumptions.
Over an algebraically closed field of characteristic 0, any unipotent abelian connected algebraic group is isomorphic to a product of copies of the additive group G a{\displaystyle G_{a.
A connected linear algebraic group G over an algebraically closed field is called semisimple if every smooth connected solvable normal subgroup of G is trivial.
For a reductive group G over a field of characteristic zero, all representations of G(as an algebraic group) are completely reducible, that is, they are direct sums of irreducible representations.
Let G be a linear algebraic group over the rational numbers Q. Then G can be extended to an affine group scheme G over Z, and this determines an abstract group GZ.
A natural generalisation of the construction above is as follows: let F{\displaystyle F} be a number field with ringof integers O{\displaystyle O} and G{\displaystyle\mathrm{G}} an algebraic group over F{\displaystyle F.
The whole group G is generated(as an algebraic group) by T and the root subgroups, while the Borel subgroup B is generated by T and the positive root subgroups.
A pseudo-reductive group over a field k(sometimes called a k-reductive group) is a smooth connected affine algebraic group defined over k whose k-unipotent radical(i.e., largest smooth connected unipotent normal k-subgroup) is trivial.
A linear algebraic group G over a field k is called simple(or k-simple) if it is semisimple, nontrivial, and every smooth connected normal subgroup of G over k is trivial or equal to G. Some authors call this property"almost simple.
For example, the projective linear group PGL(2)is connected as an algebraic group over any field, but its group of real points PGL(2,R) has two connected components.
For a connected linear algebraic group G over a local field k of characteristic zero(such as the real numbers), the group G(k) is compact in the classical topology(based on the topology of k) if and only if G is reductive and anisotropic.
In general the finite group associated to an endomorphism of a simply connected simple algebraic group is the universal central extension of a simple group, so is perfect and has trivial Schur multiplier.
More generally, a connected linear algebraic group G over an algebraically closed field is called reductive if every smooth connected unipotent normal subgroup of G is trivial.
For a perfect field k, that can be avoided: a linear algebraic group G over k is reductive if and only if every smooth connected unipotent normal k-subgroup of G is trivial.