Comments by "Dr Gamma D" (@DrDeuteron) on "Light Can Go Backwards Through Time, And This Experiment Proves It" video.

The photon timing really can’t be better the coherence time of the laser. The photon isn’t created when it is emitted, it spends a lots of time bouncing back and forth in the cavity…..and since all interference setups have to be smaller than the coherence length of the laser, the timing is always uncertain.
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@armandaneshjoo light waves? We’re talking Fock states.
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@armandaneshjoo well obviously photons don't travel backwards in time, so unless we have more info with line widths and all that, I have nothing more to say about it. It's a pretty technical set up, and handwaving at it is insufficient.
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Everyone’s understanding of light is incomplete. Everyone. Theoretical particle physicists understand QED, a relativistic quantum field theory formulation of high energy phenomena. Meanwhile, that gives ZERO insight into quantum optics, where photons are teleported and interfered on a bench in a lab. They are totally different, esp the multiphoton states in quantum optics. And then there is the classical understanding,,.,the ppl who design telecom systems or top secret radar. I’ve been in alll 3, and it is not possible to master all of them
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On the openning: “you understanding of light is incomplete”. Yes, this is true. The fraction of PhDs who can explain pair production (QED), the oo mandel other guy effect (quantum optics), hanburry-twists effect (higher order correlations), holography, SAR imaging, speckle interferometry, bells space ship paradox, the Glauber state, without consulting material is well below 1.
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