[Xcelerate]

It’s kind of intriguing that predicting the future state of any quantum system becomes almost trivial—assuming you can diagonalize the Hamiltonian. But good luck with that in general. (In other words, a “simple” reference frame always exists via unitary conjugation, but finding it is very difficult.)

[srean]

Indeed.

It's disconcerting at times, the scope of finite and infinite dimensional linear algebra, especially when done on a convenient basis.