Примеры использования Dynkin diagrams на Английском языке и их переводы на Русский язык
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Dynkin diagrams may also arise in other contexts.
The McKay correspondence can be extended to multiply laced Dynkin diagrams, by using a pair of binary polyhedral groups.
Extended Dynkin diagrams(affine) are given"+" and represent one added node.
Ree realized that a similar construction could be applied to the Dynkin diagrams F4 and G2, leading to two new families of finite simple groups.
Dynkin diagrams correspond to and are used to classify root systems and therefore semisimple Lie algebras.
So far no one has yet found a clean uniform description of the finite simple groups similar to the parameterization of the compact Lie groups by Dynkin diagrams.
Very-extended Dynkin diagrams with 3 nodes added are given.
Dropping the direction on the graph edges corresponds to replacing a root system by the finite reflection group it generates, the so-called Weyl group, andthus undirected Dynkin diagrams classify Weyl groups.
In this case the Dynkin diagrams exactly coincide with Coxeter diagrams, .
At the level of diagrams, this is necessary as otherwise the quotient diagram will have a loop, due to identifying two nodes but having an edge between them, andloops are not allowed in Dynkin diagrams.
One then classifies Dynkin diagrams according to the constraints they must satisfy, as described below.
The A, D, E nomenclature also yields thesimply laced finite Coxeter groups, by the same diagrams: in this case the Dynkin diagrams exactly coincide with the Coxeter diagrams, as there are no multiple edges.
Same as"~" Over-extended Dynkin diagrams(hyperbolic) are given"^" or"++" and represent two added nodes.
Dynkin diagrams are closely related to Coxeter diagrams of finite Coxeter groups, and the terminology is often conflated.
The fundamental interest in Dynkin diagrams is that they classify semisimple Lie algebras over algebraically closed fields.
Dynkin diagrams have the additional restriction that the only permitted edge labels are 2, 3, 4, and 6.
A further difference, which is only stylistic,is that Dynkin diagrams are conventionally drawn with double or triple edges between nodes(for p 4, 6), rather than an edge labeled with"p.
Dynkin diagrams are equivalent to generalized Cartan matrices, as shown in this table of rank 2 Dynkin diagrams with their corresponding 2x2 Cartan matrices.
Compact hyperbolic Dynkin diagrams exist up to rank 5, and noncompact hyperbolic graphs exist up to rank 10.
Dynkin diagrams are named for Eugene Dynkin, who used them in two papers(1946, 1947) simplifying the classification of semisimple Lie algebras; see Dynkin 2000.
The simply laced Dynkin diagrams, those with no multiple edges(A, D, E) classify many further mathematical objects; see discussion at ADE classification.
Dynkin diagrams can be interpreted as classifying many distinct, related objects, and the notation"An, Bn,…" is used to refer to all such interpretations, depending on context; this ambiguity can be confusing.
These are two of the four families of Dynkin diagrams(omitting B n{\displaystyle B_{n}} and C n{\displaystyle C_{n}}), and three of the five exceptional Dynkin diagrams omitting F 4{\displaystyle F_{4}} and G 2{\displaystyle G_{2.
Dynkin diagrams differ from Coxeter diagrams of finite groups in two important respects: Partly directed Dynkin diagrams are partly directed- any multiple edge(in Coxeter terms, labeled with"4" or above) has a direction(an arrow pointing from one node to the other); thus Dynkin diagrams have more data than the underlying Coxeter diagram undirected graph.
The right map is simply an inclusion- undirected Dynkin diagrams are special cases of Coxeter diagrams, and Weyl groups are special cases of finite Coxeter groups- and is not onto, as not every Coxeter diagram is an undirected Dynkin diagram(the missed diagrams being H3, H4 and I2(p) for p 5 p≥ 7), and correspondingly not every finite Coxeter group is a Weyl group.
Dynkin diagrams are closely related objects, which differ from Coxeter diagrams in two respects: firstly, branches labeled"4" or greater are directed, while Coxeter diagrams are undirected; secondly, Dynkin diagrams must satisfy an additional(crystallographic) restriction, namely that the only allowed branch labels are 2, 3, 4, and 6.
Then Dynkin diagrams and Coxeter diagrams may be related as follows: By this is meant that Coxeter diagrams of finite groups correspond to point groups generated by reflections, while Dynkin diagrams must satisfy an additional restriction corresponding to the crystallographic restriction theorem, and that Coxeter diagrams are undirected, while Dynkin diagrams are(partly) directed.
See Dynkin diagram generator for diagrams. .
The term"Dynkin diagram" can be ambiguous.
For a quasi-split group, every Galois orbit in the Dynkin diagram is circled.