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This TED talk suggests that we can now watch as a beam of light propagates through a bottle filled with water. My question is: can we use this new technology to perhaps 'see' the photon as it makes its way to the detector screen in the double slit experiment? What implications can femto-photography have on the single/double-slit experiment and physics in general?

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In the video, Dr Raskar describes the process a little more in-depth. To create the femto-photography videos, his team actually takes extremely short exposures of a light pulse travelling through a medium (e.g. a bottle filled with water) at very precisely synchronised time intervals, so they are basically shooting packets of light at the target one-by-one very many times and taking a picture each time with another time offset.

In effect, you're making a measurement each time, registering the photon's position in space. Its wave function collapses, resulting in a random position in each frame (subject to the double-slit interference probability distribution).

What this means is that you aren't seeing (measuring) the same light pulse travelling through the object, but you're seeing a different light pulse in each frame. If you tried to 'see' a photon make its way to the detector screen in the double slit experiment, you would 'see' it at a point in the space between the double slit and the screen, but every time at a different, random position. (Disregarding the fact that you would need it to scatter off something to detect it with an external camera...)

I'm guessing this technology does not provide any further information about the double-slit experiment or quantum mechanics in general, but it is damn impressive!

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