The only way in which the path of a light ray can be bent is by the process of refraction. The amount of refraction (deviation from its original path) is a function of both the wavelength of light involved and the difference in densities of the mediums involved. This gives us a ratio known as the refractive index.
Note that even refraction does not cause a light ray to follow a curved path (as seems to be implied by the diagrams of FE electromagnetic acceleration) but rather it changes instantaneously the direction of an otherwise straight path.
As I pointed out earlier the atmosphere causes a slight refraction effect because air is denser than the vacuum of space beyond and the density of the atmosphere decreases with height above the surface. I also mentioned how this refraction effect is very small compared to the amount of bending that the FE Wiki seems imply takes place as per
https://wiki.tfes.org/Electromagnetic_AccelerationRather it is in the order of arc minutes which would be barely noticeable to the naked eye. Here's a graph to show how the amount of refraction (in arc minutes) varies with altitude in degrees.
https://en.wikipedia.org/wiki/Atmospheric_refraction#/media/File:BennettAtmRefractVsAlt.pngVideos have been posted before by FE'ers claiming to provide evidence the 'bending' of light such as this one
But of course that is not the light bending but an example of light undergoing total internal reflection within the flow of water coming out of the bottle.