Why the rank of an irreducible tensor must be an integer?

  • Context: Graduate 
  • Thread starter Thread starter wdlang
  • Start date Start date
  • Tags Tags
    Integer rank Tensor
Click For Summary
SUMMARY

The rank of an irreducible tensor must be an integer due to the properties of the rotation group representations. Specifically, when considering the tensor defined by the commutation relation [J_z, T^k_q] = q T^k_q, the indices of the tensor, k and q, can represent half-integer values. However, the Clebsch-Gordan decomposition applied to these representations results exclusively in integer representations, confirming that irreducible tensors cannot possess half-integer ranks.

PREREQUISITES
  • Understanding of irreducible representations in group theory
  • Familiarity with the rotation group and its properties
  • Knowledge of Clebsch-Gordan decomposition
  • Basic concepts of tensor algebra
NEXT STEPS
  • Study the properties of the rotation group and its irreducible representations
  • Learn about the Clebsch-Gordan decomposition in detail
  • Explore the implications of tensor algebra in quantum mechanics
  • Investigate the role of tensors in particle physics
USEFUL FOR

Physicists, mathematicians, and students studying quantum mechanics or group theory, particularly those interested in the application of tensors in theoretical physics.

wdlang
Messages
306
Reaction score
0
why not half-integer?

according to the definition, such as [J_z,T^k_q]=q T^k_q

it is quite possible that k can be a half-integer.
 
Physics news on Phys.org
Well, in that context, a tensor has usually two indices, i.e. it transforms as the product of two equal irreducible representations of the rotation group these two representations may be either both integer or both half integer. In any case, the Clebsch Gordon decomposition will yield only integer representations.
 

Similar threads

  • · Replies 9 ·
Replies
9
Views
2K
  • · Replies 4 ·
Replies
4
Views
3K
  • · Replies 1 ·
Replies
1
Views
2K
Replies
8
Views
3K
  • · Replies 2 ·
Replies
2
Views
1K
  • · Replies 6 ·
Replies
6
Views
3K
Replies
5
Views
3K
  • · Replies 5 ·
Replies
5
Views
2K
  • · Replies 1 ·
Replies
1
Views
3K
  • · Replies 9 ·
Replies
9
Views
2K