[AndyJackson]

The stuff that QM is used for in the everyday work of practical applications can probably be counted on one or two hands. E.g., superconductors, superfluids. (Unless you are claiming lasers and semiconductors, etc., as in the provenance of QM, which I think is an over extension

But lasers and semiconductors are smack in the middle of the provenance of QM and if you had read the papers of Schawlow and Townes on the one hand, or Bardeen on the other hand, you would understand that point. These things were invented exactly because their inventors were the brilliant and highly able students of those who invented Quantum Mechanics.

[Sam Hill]

I knew somebody was going to say that, which is why I said bringing up lasers, etc., is expanding the credit for QM.

Lasers were discovered in the course of studying photoelectric effect -- not Quantum Mechanics, per se.

[Sam Hill]

"These things were invented exactly because their inventors were the brilliant and highly able students of those who invented Quantum Mechanics."

I realize why you are saying that. And probably it's right, since these things come out of Planck by way of Einstein.

Even accepting that, lasers, etc., are still a small fraction of doing stuff. In my earlier posts I acknowleged that the category of QM things is growing rapidly. But it is still a fraction of things in the practical world (i.e., applied physics).

And, again, most if not all of these things could be "described" just as effectively by classical physics.