It’s fun to see how teaching about 2-level atoms and lie group generators discussed in terms of group |g> and excited states |e>, S^{2}, Sz and S-/S+ operators can be generalized. Seeing the generalization actually helps understand the qubit model, better. You realize that the case of generators and operators is just a special case of same world expressed more generally in and about qudits. In particular, one learns how to dump the physics notation – though its still very useful for intuition to think in terms of atoms, energy levels, electron spins, bosonic/fermionic anti-symmetry, braid groups, etc etc .

http://arxiv.org/abs/quant-ph/0001075

One sees the clear overlap now between 1950s cryptanalysis theory and physics (and why the work in open physics was so hampered).

## About home_pw@msn.com

Computer Programmer who often does network administration with focus on security servers. Very strong in Microsoft Azure cloud!