## anonymous 3 years ago physical explanation of accidental degenaracy

1. anonymous

Symmetry.

2. anonymous

what type of symmetry?? i mean for hydrogen atom,the energy eigen values are degenerate w.r.t l i.e,potential is central i.e,v(r)=-1/r^m.why it is called accidental??

3. anonymous

The radial symmetry of the potential gives you the degeneracy in m, which is "expected." The additional symmetry that produces the "accidental" (unexpected) degeneracy in l is conservation of the Lenz vector:${\bf p} \times {\bf L} - \frac{1}{r} {\bf r}$Roughly speaking, it's the fact that in a 1/r potential the direction of an elliptical orbit does not change.