Reducing Symmetry from SU(2) to U(1): A Guide | Dear PF

  • Thread starter Neitrino
  • Start date
  • Tags
    Symmetry
In summary, SU(2) and U(1) are mathematical groups used in theoretical physics to study quantum mechanics and particle physics. Reducing symmetry is the process of simplifying a system by removing certain symmetries or constraints, allowing for a better understanding of complex systems. This is important in physics because it can reveal underlying patterns and relationships. An example of reducing symmetry is the unification of SU(2) and U(1) in the electroweak theory, which has practical applications in technologies such as particle accelerators and medical imaging devices.
  • #1
Neitrino
137
0
Dear PF,

I don't know whether this is the right place for such question, but
how to reduce symmetry suppose from SU(2) symmetric Lagrangian down to U(1)?

Thank you
 
Physics news on Phys.org
  • #2
You can't. If you let the Higgs doublet acquire an VEV in a SU(2) invariant theory, you break the entire SU(2) symmetry and end up with with three massive gauge bosons.

You can however break down SU(2)xU(1) to a (nontrivial) subgroep U(1). This is what is done in the Electroweak theory.
 
  • #3
Thank you Dimitri
 

1. What is SU(2) and U(1)?

SU(2) and U(1) are both mathematical groups used in theoretical physics, specifically in the study of quantum mechanics and particle physics. SU(2) stands for Special Unitary Group of degree 2, while U(1) stands for Unitary Group of degree 1.

2. What does "Reducing Symmetry" mean?

Reducing symmetry refers to the process of simplifying a system by removing certain symmetries or constraints. In the context of SU(2) and U(1), it involves finding a way to reduce the number of dimensions in a system without changing its overall properties.

3. Why is reducing symmetry important in physics?

Reducing symmetry allows physicists to better understand and analyze complex systems by simplifying them. It can also help reveal underlying patterns and relationships that may not be apparent in the original system. In the case of SU(2) and U(1), reducing symmetry is important in studying the behavior of subatomic particles and their interactions.

4. Can you give an example of reducing symmetry from SU(2) to U(1)?

One example is the electroweak theory, which combines the electromagnetic and weak nuclear forces. This theory was developed by unifying the SU(2) and U(1) symmetries through the Higgs mechanism, resulting in the reduction of symmetry from SU(2) to U(1).

5. What are some practical applications of reducing symmetry from SU(2) to U(1)?

The successful unification of the SU(2) and U(1) symmetries in the electroweak theory has led to the development of technologies such as particle accelerators and medical imaging devices. It has also helped in our understanding of the fundamental forces of nature and the behavior of subatomic particles.

Similar threads

  • High Energy, Nuclear, Particle Physics
Replies
2
Views
607
  • Beyond the Standard Models
2
Replies
61
Views
6K
Replies
52
Views
12K
  • Beyond the Standard Models
Replies
4
Views
3K
Replies
7
Views
1K
  • Beyond the Standard Models
Replies
27
Views
7K
Replies
3
Views
919
  • Beyond the Standard Models
Replies
11
Views
3K
  • Beyond the Standard Models
Replies
17
Views
4K
  • Linear and Abstract Algebra
Replies
1
Views
980
Back
Top