Math 2.0

Group theory and generalizations Definition

Simple group

Builds on Normal subgroup

Definition

A group GG is simple when G≠{e}G \neq \{e\} and the only normal subgroups of GG are {e}\{e\} and GG.

Remarks

The cyclic groups ℤ/pℤ\mathbb{Z}/p\mathbb{Z} of prime order pp are simple, and they are the only abelian simple groups. The alternating group AnA_n is simple for n≥5n \geq 5, and A5A_5 is the smallest simple group that is not abelian. A simple group has only the trivial quotient and itself as quotients, so it cannot be split into smaller pieces by a quotient.

Reading path

To understand this page from the ground up, read these 6 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. Group concept
  2. Conjugate elements definition
  3. Subgroup definition
  4. Conjugate subgroup definition
  5. Normal subgroup definition
  6. Simple group definition

Where this leads

13 pages build on this one.

Further reading

  1. Web https://en.wikipedia.org/wiki/Simple_group, lead section
About this page
Tag0C093D1T4M
URIm2://0C093D1T4M
Kinddefinition
WritingW1 stated
MSC20E32
DefinesSimple group
UsesNormal subgroup

Markdown · JSON · Edit on GitHub

What this page needs for W2

  • edge not_instance_of in: one non-example that fails one clause (0 of 1)

The writing levels say how complete the text of a page is. They do not measure its truth.

What links here

Used by