- #1
LagrangeEuler
- 717
- 20
I'm not sure what people meant about this. Heisenberg hamiltonian is ##O(3)## invariant.
[tex]H=-J\sum_{\langle i,j \rangle} \vec{S}_i \cdot \vec{S}_j[/tex]
##\langle \rangle## denotes nearest neighbors.
It has ##O(3)## symmetry. If I understand well ground state is infinitely degenerate. But system must choose some ground state. Now where is symmetry breaking here?
[tex]H=-J\sum_{\langle i,j \rangle} \vec{S}_i \cdot \vec{S}_j[/tex]
##\langle \rangle## denotes nearest neighbors.
It has ##O(3)## symmetry. If I understand well ground state is infinitely degenerate. But system must choose some ground state. Now where is symmetry breaking here?