Schroedinger's Equation at 100: The Wave Picture That Helped and Possibly Hurt

Caslav Brukner

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arXiv · 2604.26325

Schroedinger's Equation at 100: The Wave Picture That Helped and Possibly Hurt

Caslav Brukner

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Abstract

Schroedinger's equation gave early quantum theory a visual language that looked like physics again: a wave evolving by a linear differential equation. This essay argues that the same success also seeded a recurring impulse to keep quantum theory "classical-looking" by treating the wave function as a physical wave. Schroedinger quickly realized that, for many-particle systems, the wave function is naturally defined on configuration space rather than ordinary physical space, blocking any straightforward reading of it as a literal classical wave. Read through Mach and Boltzmann, who shaped his intellectual outlook most deeply, his achievement appears double-edged: it provided an extraordinarily powerful picture for calculation and discovery, while also warning against taking that picture too literally. I argue that this tension never fully disappeared. It still reappears in modern physics whenever the wave function, or in quantum field theory the field itself, is treated as ontology rather than as part of a representation tied to measurement and observational context, a point sharpened by Bell-type no-go theorems. The centenary moral is: use pictures boldly, but demote them ontologically.

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Caslav Brukner. 2026-04-29. Schroedinger's Equation at 100: The Wave Picture That Helped and Possibly Hurt. https://arxiv.org/abs/2604.26325

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