- #1
bob900
- 40
- 0
Suppose we have three hermitian operators A,B,C each with only non degenerate eigenvalues.
If A and B commute, then for each eigenvector of A we can find an eigenvector of B, and because the eigenvalues are non degenerate the mapping is one to one. If B and C commute we can do the same. This implies that A and C also have a one to one mapping of their eigenbases, and so A and C commute.
But in general we know that the commutation relation is not transitive for some arbitrary set of operators {X,Y,Z}. Is this because some of them might have degenerate eigenvalues?
If A and B commute, then for each eigenvector of A we can find an eigenvector of B, and because the eigenvalues are non degenerate the mapping is one to one. If B and C commute we can do the same. This implies that A and C also have a one to one mapping of their eigenbases, and so A and C commute.
But in general we know that the commutation relation is not transitive for some arbitrary set of operators {X,Y,Z}. Is this because some of them might have degenerate eigenvalues?