In a way, nature is so mysterious that things we see and the explanations we give, might not be the true picture at all. How do we know nature’s true properties? Let’s hold this line as it will divert to too much philosophy.
As per Ernst Mach, a scientific theory must be economical, in terms of ideas it uses. Observed values(like splitting of spectral lines) should be connected with mathematical ideas to arrive at conclusions(as tested by experiment). When Schrodinger published his wave mechanics, Heisenberg did the same with his matrix mechanics. The conclusions arrived at were equivalent. Yet, Schrodinger has used continuum/wave ideas whereas Heisenberg has just crunched the numbers. As we can hardly “observe” waves inside an atom, Ernst Mach would have preferred Heisenberg’s theory.
Though Schrodinger and Heisenberg were nice on the surface, they criticised each other in personal letters. Schrodinger wrote to Lorentz that ideas of quantum jumps were “monstrous”. Young Heisenberg wrote Pauli that the continuum ideas looked “bullshit”. When at an after-lecture session, Heisenberg asked Schrodinger how he supposes to explain photoelectric effect and blackbody radiation; Willy Wien treated as if to throw him out. Wien angrily said, “Young man. These effects will be duly explained”.
With the advent of quantum mechanics, physics already entered a far-abstract realm. Old-school physicists tended to side with Schrodinger, as he preserved the semi-classical nature of physics they were trained in. Younger generation physicists(like Pauli, Dirac and Heisenberg) were finally breaking all the old-school ideas.
Even after decades, the philosophical discussions continue. String theory, Standard Model of particles, cosmology and host of other stuff. Personally, I don’t have the skill-set to follow all these discussions. It feels that the journey has become obscure again.
(inspired by Walter Moore’s biography of Schrodinger)
