Paper
1950
On the Adiabatic Theorem of Quantum Mechanics
Tosio Kato
Gives the first mathematically rigorous proof that a quantum system changed slowly enough stays in its instantaneous eigenstate, putting the adiabatic approximation used throughout perturbation theory on firm ground.
No free copy is linked yet — expect to buy or borrow this one elsewhere.
Groundwork for
Works in the library that name this one as a prerequisite.
Filed under Quantum Mechanics in Physics.