Comments by "Dr Gamma D" (@DrDeuteron) on "How Physicists Created the Double Slit Experiment In Time" video.

  1. The photon doesn't come into existence when it pops out of the laser aperture, it bounces back and forth in the laser cavity for a while (the coherence time) before that, so it's not quantum woo that a single photons state can exist over significant duration (much longer than pico seconds....internet says from 600ps to 300 microsecond...which is 20cm to 1 km in spatial extent).
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