Английская Википедия:Diameter (group theory)

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In the area of abstract algebra known as group theory, the diameter of a finite group is a measure of its complexity.

Consider a finite group <math>\left(G,\circ\right)</math>, and any set of generators Шаблон:Mvar. Define <math>D_S</math> to be the graph diameter of the Cayley graph <math>\Lambda=\left(G,S\right)</math>. Then the diameter of <math>\left(G,\circ\right)</math> is the largest value of <math>D_S</math> taken over all generating sets Шаблон:Mvar.

For instance, every finite cyclic group of order Шаблон:Mvar, the Cayley graph for a generating set with one generator is an Шаблон:Mvar-vertex cycle graph. The diameter of this graph, and of the group, is <math>\lfloor s/2\rfloor</math>.[1]

It is conjectured, for all non-abelian finite simple groups Шаблон:Mvar, that[2]

<math>

\operatorname{diam}(G) \leqslant \left(\log|G|\right)^{\mathcal{O}(1)}. </math>

Many partial results are known but the full conjecture remains open.[3]

References

Шаблон:Reflist


Шаблон:Group-theory-stub

  1. Шаблон:Citation.
  2. Шаблон:Harvtxt, Conj. 1.7. This conjecture is misquoted by Шаблон:Harvtxt, who omit the non-abelian qualifier.
  3. Шаблон:Citation.