How Do Continuous Linear Representations of S^1 Function in Hilbert Spaces?

Click For Summary
SUMMARY

The continuous linear representations of S^1 on a separable Hilbert space H are defined similarly to those in finite-dimensional cases due to the compactness of S^1. Every continuous linear representation is unitary and can be decomposed into a direct sum of irreducible representations. Since S^1 is abelian, its irreducible representations correspond to its characters, which are one-dimensional. This establishes a clear framework for understanding these representations in Hilbert spaces.

PREREQUISITES
  • Understanding of separable Hilbert spaces
  • Knowledge of unitary representations
  • Familiarity with compact groups, specifically S^1
  • Concept of irreducible representations and characters
NEXT STEPS
  • Research the properties of unitary representations in Hilbert spaces
  • Study the structure of compact groups and their representations
  • Explore the concept of characters in representation theory
  • Learn about the decomposition of representations into irreducible components
USEFUL FOR

Mathematicians, physicists, and students studying functional analysis, representation theory, or quantum mechanics who seek to understand the application of continuous linear representations in Hilbert spaces.

HMY
Messages
13
Reaction score
0
Let H be a separable Hilbert space. What are the continuous
linear representations of S^1 on H?

I read in an article this is defined as in the finite-dim case.
Why is this so?

Thanks.
 
Physics news on Phys.org
Well S^1 is compact, so every continuous linear representation of S^1 on H is unitary (re-norm H if necessary) and decomposes into a direct sum of irreducible representations. And since S^1 is abelian, its irreducible representations are nothing other than its characters, i.e. they're one-dimensional.

Is this what you're asking?
 

Similar threads

  • · Replies 1 ·
Replies
1
Views
3K
  • · Replies 4 ·
Replies
4
Views
2K
  • · Replies 4 ·
Replies
4
Views
3K
  • · Replies 2 ·
Replies
2
Views
4K
  • · Replies 2 ·
Replies
2
Views
3K
  • · Replies 16 ·
Replies
16
Views
1K
  • · Replies 10 ·
Replies
10
Views
3K
  • · Replies 9 ·
Replies
9
Views
2K
  • · Replies 2 ·
Replies
2
Views
2K
  • · Replies 0 ·
Replies
0
Views
8K