- #1

- 1

- 0

**what is the (mathematical) justification**to represent the operator by a vector which has a direction that the operator has not. Yet worse, l(l+1) h2 is the proper value of operator

**L^2**and from

**such result**it is assumed that (l(l+1))^1/2 is the length of operator

**L**. Such trick-representation seems to be a strong convention, but it does not make it mathematically correct.