Physicist David Bohm, who developed a non-local formulation of quantum mechanics that he hoped would evade some of the conceptually thorny aspects of the Copenhagen Interpretation, and would later inspire the work of John Bell, was born #OTD in 1917.
Bohm’s quantum mechanics textbook was published in 1951. It was very successful, and is still available from Dover as a reprint. It's a great book.
I almost said “inexpensive reprint," but then I checked the Dover website. It's $40 now! A few years ago it was $25, and when I bought it, the book was $14. Dover-flation!
https://store.doverpublications.com/0486659690.html
Anyway, here's my copy:
That same year, a crotchety old faculty member named Einstein encouraged the young Bohm to study von Neumann’s work scrutinizing “hidden variable theories.”
These are theories that assert additional deterministic variables whose state and dynamics, were they known to us, would resolve the indeterminacy of quantum mechanics.