Is the Fundamental group of the circle abelian?

In summary, the Fundamental group of the circle (S^1) is abelian because it is isomorphic to the abelian group of integers.
  • #1
fraggle
19
0

Homework Statement


Is the Fundamental group of the circle (S^1) abelian?

Not a homework question, just something I want to use.


Homework Equations




The Attempt at a Solution


Intuitively it appears to be and it is isomorphic to the additive group of integers which is abelian. I believe isomorphism preserve the abelian property. I'd just like a second opinion.

Thanks
 
Physics news on Phys.org
  • #2
The fundamental group of the circle is the integers, which is abelian.
 
  • #3
fraggle said:

Homework Statement


Is the Fundamental group of the circle (S^1) abelian?

Not a homework question, just something I want to use.


Homework Equations




The Attempt at a Solution


Intuitively it appears to be and it is isomorphic to the additive group of integers which is abelian. I believe isomorphism preserve the abelian property. I'd just like a second opinion.

Thanks

If you have an isomorphism from G to H, call it f, and H is abelian then

f(gh)=f(g)f(h)=f(h)f(g) (since H is abelian) = f(hg)

So f(gh)=f(hg) which means gh=hg since f is a bijection. Hence G is abelian too
 

Related to Is the Fundamental group of the circle abelian?

What is the fundamental group of the circle?

The fundamental group of the circle is the group of all loops on the circle starting and ending at the same point. It is denoted by π1(S1) or simply π1.

Is the fundamental group of the circle abelian?

Yes, the fundamental group of the circle is abelian. This means that the group operation is commutative, and the order in which the loops are composed does not matter.

How is the fundamental group of the circle calculated?

The fundamental group of the circle can be calculated using the fundamental theorem of algebraic topology, which states that the fundamental group of a space is isomorphic to the group of its covering spaces. In the case of the circle, the group is isomorphic to the integers.

What is the significance of the fundamental group of the circle?

The fundamental group of the circle is significant in topology and geometry, as it helps to classify and distinguish different types of spaces. It also has applications in fields such as physics and computer science.

Can the fundamental group of the circle be non-abelian?

No, the fundamental group of the circle is always abelian. This is because the circle is a simply connected space, meaning that any loop on the circle can be continuously deformed into a point without leaving the space. This property ensures that the fundamental group is always abelian.

Similar threads

  • Calculus and Beyond Homework Help
Replies
3
Views
1K
  • Calculus and Beyond Homework Help
Replies
1
Views
1K
  • Calculus and Beyond Homework Help
Replies
9
Views
2K
  • Calculus and Beyond Homework Help
Replies
2
Views
994
  • Calculus and Beyond Homework Help
Replies
5
Views
1K
  • Calculus and Beyond Homework Help
Replies
3
Views
1K
  • Calculus and Beyond Homework Help
Replies
5
Views
2K
  • Calculus and Beyond Homework Help
Replies
4
Views
1K
  • Calculus and Beyond Homework Help
Replies
4
Views
3K
  • Calculus and Beyond Homework Help
Replies
16
Views
2K
Back
Top