Comment by aarond0623 | Hacker News Reader

Comment by aarond0623 | Hacker News Reader

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The first one was portrayed in a clickbait "everything you know about electricity is wrong" way. There have been several response videos to it that lay out why it's misleading that explain it better than I can, but suffice to say that the lightbulb does not turn on immediately like he claims.

There second one takes a mathematical model for the path integral for light and portrays it like that's actually what is happening, with plenty of phrases like light "chooses" the path of least action that imply something more going on. Also, the experiment at the end with the laser pointer is awful. The light we are seeing is scattering from the laser pointer's aperture, not some evidence that light is taking alternate paths.

> suffice to say that the lightbulb does not turn on immediately like he claims

Many people said this, but he set up an experiment to test it and the light does turn on instantly as claimed: https://www.youtube.com/watch?v=oI_X2cMHNe0

> There second one takes a mathematical model for the path integral for light and portrays it like that's actually what is happening

I know nothing about this. Is there a more accurate mathematical model available than the one he uses? Otherwise, I think it seems sensible to portray our best mathematical model as "what's really going on". And I didn't get the sense that light was "choosing" anything when watching the video, I got the sense that the amplitudes of all possible paths were cancelling out except for the shortest path (or something along those lines)

There are many equivalent formulations of quantum mechanics, the one the above post takes issue with is the path integral formulation. But because you can show an exact mathematical equivalence it makes all the same predictions as, for example, Hamiltonian evolution.

The words people like to use for the path integral is a sum over histories---that corresponds tightly with the ingredients in the path integral. So in this formulation it's what's "actually happening". But in other mathematical formulations other words are more appealing and what someone claims is "actually happening" sounds different.

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