Recent content by zhangpujumbo

Dirac's QM

I still want to know how helicity is related to polarization. Can you recommend some readings? Thank you!

in the attachment. Why the grand total angular momentum is 0? thank u!

I've seen some arguments about your question in the Dirac's classic QM textbook. Any more opinions?

Then sometimes the boundary conditions do make a difference.

I see in many textbooks that all authors start field quantization with EM field confined in a cube of finite size, certainly some B.C. is imposed, usually periodic B.C., finally the cube goes to whole space. I have some questions on this procedure: 1, Is periodic(or other) B.C. reasonable...

I think a compact software like mathtype will help greatly.

It is said that two eigenstates of spin correspond to two kinds of circularly polarized states, but I don't know the details too. Anyone knows what subject deals with this stuff? Thank u!

It seems that all the equations are copied piece by piece, then typying equations will be too laborious a task Is there a shortcut?

Are topics on Optical Engineering also included in this subforum?

I don't know how to type mathematical equations here, it's too inconvenient.:cry: How do you do that?

en, it's clearer.

I don't mean all wavefunctions must be complex. But thank u all the same!

Yes, I agree with your opinion very much!:approve: There must be something wrong. Thanks a lot:smile:

I feel such a warm welcome here! Thank u all:smile: