On Unitary Evolution and Collapse in Quantum Mechanics

  title={On Unitary Evolution and Collapse in Quantum Mechanics},
  author={Francesco Giacosa},
In the framework of an interference setup in which only two outcomes are possible (such as in the case of a Mach–Zehnder interferometer), we discuss in a simple and pedagogical way the difference between a standard, unitary quantum mechanical evolution and the existence of a real collapse of the wavefunction. This is a central and not-yet resolved question of quantum mechanics and indeed of quantum field theory as well. Moreover, we also present the Elitzur–Vaidman bomb, the delayed choice… 

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