"I don't like it, and I'm sorry I ever had anything to do with it"

Erwin Schrödinger, one of the central figures in the development of quantum mechanics, expressed deep ambivalence about the discipline he helped establish. His famous line, "I don't like it, and I'm sorry I ever had anything to do with it", embodies the complex emotions felt by some early quantum physicists who were simultaneously creators and critics of the theory’s unsettling implications. Schrödinger’s reluctance was not due to a lack of appreciation for the predictive power or utility of quantum mechanics. On the contrary, he contributed major advancements, most famously the Schrödinger equation, which remains a foundational achievement. Nevertheless, he struggled with the theory’s probabilistic nature and its abandonment of classical notions of reality and determinism.

Before quantum mechanics, physics, rooted in the Newtonian tradition, offered a worldview where particles had specific positions and velocities, governed by laws that predicted the future with certainty if the present was known. Quantum theory, especially as interpreted through the Copenhagen interpretation, shattered this certainty. It introduced inherent randomness at a fundamental level, suggesting that the precise state of a system could only be described by probabilities, not certainties. Observables did not possess definite values until actively measured.

Schrödinger’s distaste stemmed from this philosophical departure. He famously illustrated the theory’s paradoxes with the thought experiment known as Schrödinger’s cat, a scenario in which a cat could exist in a superposition of being both alive and dead until observed. Such a conclusion felt absurd and unsettling, as it questioned the nature of reality itself. Schrödinger’s regret, then, arose from witnessing the shift away from a clear, tangible, and objective universe toward a realm filled with ambiguity, paradox, and a limited capacity for complete knowledge, a shift which, for him, was deeply unsatisfying at an intellectual and philosophical level.