Addition of Angular Momentum for identical particles

Click For Summary
SUMMARY

The discussion focuses on the addition of angular momentum for identical particles with spin 1, specifically addressing the differences in total spin states when particles are distinguishable versus identical. For distinguishable particles, total spin states can be j=0, 1, or 2. However, for identical particles, the total state must be (anti-)symmetric according to Bose or Fermi statistics, which affects the construction of states. The participant seeks clarity on how to derive the states for j=0 and j=1 from the j=2 states using ladder operators.

PREREQUISITES
  • Understanding of angular momentum addition in quantum mechanics
  • Familiarity with spin-1 particles
  • Knowledge of Bose-Einstein and Fermi-Dirac statistics
  • Experience with ladder operators in quantum mechanics
NEXT STEPS
  • Study the application of ladder operators in constructing quantum states
  • Research the implications of Bose and Fermi statistics on identical particles
  • Explore the mathematical framework of symmetric and antisymmetric wave functions
  • Investigate the addition of angular momentum for systems with higher spins
USEFUL FOR

Quantum physicists, students of quantum mechanics, and researchers studying particle statistics and angular momentum in identical particle systems.

Gabriel Maia
Messages
70
Reaction score
1
This is the problem I'm trying to understand:

Consider two particles with spin 1 without orbital angular momentum. If they are distinguishable, from the rule of addition of angular momentum applied to spin, we'll have states of total spin j=0,1,2. If we have, however, identical particles which are the possible states?

In textbooks, the addition of angular momentum is never treated in terms of distinguishable and identical particles, at least I don't recall it. The way I would approach this problem is to acknowledge that the possible total spin would be j=0,1,2 and then, from the state |-1\rangle |-1\rangle, I would use the ladder operator to build all the other four states compatible with j=2. How do I build the states for j=0,1? The state |j=1,m_{j}=-1\rangle must be built from the same states as |j=2,m_{j}=-1\rangle, that is, |-1\rangle |0\rangle and |0\rangle |-1\rangle. So how are they any different?

Thank you very much.

The Attempt at a Solution

 
Physics news on Phys.org
What is important for distinguishable particles is that the total state is (anti-)symmetric (depending on Bose/Fermi statistics). You need to take the spin state into account as well as the spatial wave function.
 

Similar threads

  • · Replies 1 ·
Replies
1
Views
2K
Replies
5
Views
1K
  • · Replies 10 ·
Replies
10
Views
2K
Replies
17
Views
2K
Replies
3
Views
2K
Replies
10
Views
3K
  • · Replies 5 ·
Replies
5
Views
2K
Replies
17
Views
3K
  • · Replies 1 ·
Replies
1
Views
3K
  • · Replies 5 ·
Replies
5
Views
2K