Math 2.0

Group theory and generalizations Definition

Solvable group

Builds on Subnormal seriesAbelian group

Definition

A group GG is solvable when it has a subnormal series {e}=G0⊴G1⊴⋯⊴Gn=G\{e\} = G_0 \trianglelefteq G_1 \trianglelefteq \cdots \trianglelefteq G_n = G in which each factor Gi/Gi−1G_i / G_{i-1} is abelian.

Remarks

Equivalently, the derived series of GG reaches {e}\{e\} after finitely many steps. A finite group is solvable if and only if its composition factors are all cyclic of prime order. The group S4S_4 is solvable, by the series {e}⊴V⊴A4⊴S4\{e\} \trianglelefteq V \trianglelefteq A_4 \trianglelefteq S_4. The name comes from Galois theory: a polynomial equation over ℚ\mathbb{Q} is solvable by radicals if and only if its Galois group is solvable.

Reading path

To understand this page from the ground up, read these 14 pages in order. The foundations come first.

Show the path as a graph
Each page uses the pages above it. The colour of the bar on a box shows how strong the evidence is, and the box also gives it as text. The list has the same pages.
  • no evidence level
  1. Binary operation definition
  2. Group concept
  3. Commutativity definition
  4. Conjugate elements definition
  5. Subgroup definition
  6. Abelian group definition
  7. Conjugate subgroup definition
  8. Left coset definition
  9. Right coset definition
  10. Normal subgroup definition
  11. Normality via left and right cosets statement
  12. Quotient group definition
  13. Subnormal series definition
  14. Solvable group definition

Where this leads

13 pages build on this one.

Further reading

  1. Web https://en.wikipedia.org/wiki/Solvable_group, Definition
About this page