Proof: S_n is Not Abelian for n >= 3

  • Context: Graduate 
  • Thread starter Thread starter TsunamiJoe
  • Start date Start date
Click For Summary

Discussion Overview

The discussion revolves around proving that the symmetric group S_n is not abelian for any n >= 3. Participants explore methods to demonstrate this property, particularly through examples and experimentation with specific cases like S_3 and S_4.

Discussion Character

  • Exploratory, Homework-related, Technical explanation

Main Points Raised

  • One participant expresses confusion about how to approach the problem and requests help without simply receiving the proof.
  • Another participant suggests experimenting with S_3 to find two permutations that do not commute, and then extending this to S_4 to identify a pattern.
  • A later reply indicates that once S_3 is understood, it can be applied to S_n since S_n contains S_3 as a subgroup.
  • There is a mention of hoping that a specific participant will recognize that their example for S_3 applies to S_4 and beyond.
  • One participant notes that a textbook is not necessary for this problem, emphasizing the importance of understanding the elements of S_n and the definition of abelian.
  • Another participant clarifies that they have multiple exercises to work on and prefer to maintain a consistent thought process while tackling such problems.

Areas of Agreement / Disagreement

Participants generally agree on the approach of using specific examples to demonstrate the non-abelian nature of S_n, but there is no consensus on a definitive proof or method at this stage.

Contextual Notes

Some limitations include the reliance on understanding the properties of permutations and the definition of abelian, as well as the potential need for further clarification on the examples discussed.

Who May Find This Useful

This discussion may be useful for students studying group theory, particularly those interested in the properties of symmetric groups and non-abelian structures.

TsunamiJoe
Messages
162
Reaction score
0
I'm having troubles with this problem here -

Show [tex]S_N[/tex] is not abelian for any [tex]n >= 3[/tex]

now right now, I am simply lost, of course its late at night so that might be why, so if some help could be provided that would be appreciated, also i would like it if you didnt simply give the proof, but also explained it.
 
Physics news on Phys.org
Experiment. :smile: Start with S_3 and try to find two permutations that don't commute. Then, try S_4. Look for a pattern you can exploit.
 
Hurkyl said:
Experiment. :smile: Start with S_3 and try to find two permutations that don't commute. Then, try S_4. Look for a pattern you can exploit.
eh. Once you've done S3, you're done, since Sn contains S3 as a subgroup.
 
Yep. I'm hoping TsunamiJoe will notice that his example for S_3 will work for S_4 and all the others. :smile:
 
|~|will respond with answer tomarow, was stupid and left textbook at school|~|
 
Do you need your textbook for this? You just need to know what kind of elements are in S_N and what abelian means.
 
|~| that was not the only exercise to work on, and i try to keep a train of thought when doing maths like these |~|
 

Similar threads

  • · Replies 2 ·
Replies
2
Views
2K
  • · Replies 2 ·
Replies
2
Views
2K
  • · Replies 5 ·
Replies
5
Views
4K
  • · Replies 48 ·
2
Replies
48
Views
5K
Replies
2
Views
2K
  • · Replies 4 ·
Replies
4
Views
4K
  • · Replies 9 ·
Replies
9
Views
2K
  • · Replies 8 ·
Replies
8
Views
3K
  • · Replies 2 ·
Replies
2
Views
2K
Replies
4
Views
2K