At the end of the nineteenth century classical physics seemed on the verge of completion. Kelvin, in a famous 1900 speech, spoke of “two small clouds” on the horizon: the problem of the aether and that of blackbody radiation. Two details, apparently, in an otherwise clear sky. Those two small clouds produced, within twenty-five years, relativity and quantum mechanics: two theories that rewrote from scratch our idea of space, time, matter and cause.
Quantum theory, in particular, is not a simple “correction” of classical mechanics for small systems. It is a radical revision of the very concept of “property of a physical object”. Before a measurement, an electron does not have a defined position — just as a die spinning in the air does not have a number showing. The result emerges only at the moment of interaction with the detector.
This is the deepest conceptual challenge physics has ever thrown at common sense. And, to this day, it has not yet found unanimous interpretive agreement among physicists (Kumar 2010, Gamow 1968, Rovelli 2014).
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Topics: Fisica quantistica Skills: Analisi di casi limite e fantafisica
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