I've just realised that although they say they can accelerate electron beams that then decelerate within the magnet lens in the electron microscope, the speed of ordinary light in air, rather than in a vacuum, is almost that of the speed of light in a vacuum - ie, "the speed of light "- which according to Einstein nothing could travel faster than. So they have come up with accelerators to accelerate electron beams so that they will travel as fast as light already does - if light actually does have speed - within the traditional microscope.
I have written to essays since the last post that I'll put up later. Both incorporate at least one new point, which is that Snell's Law changed with the introduction of the electron microscope. Snell's Law is used to calculate the change in the angle as light enters a different medium because of refraction. It is: angle of incidence x sin(e) x refractive index a. = angle of refraction or transmission x sin(e) x refractive index b. So that because you have a larger refractive index with a denser material you have a smaller angle when light enters eg a lens from air. It then returns to the prior angle, of course, when exiting the lens. However, with electron optics you have a new Snell's Law where the variable is not refractive index but velocity, which is inversely proportional to refractive index since the refractive index of any material is equal to the speed, or velocity, of light in air over the speed/velocity in the material. This point is laboured in the book I have been looking at so as to make it seem they are trying to make you think about it. However, what I hadn't thought of, despite references, for example, to 'slow electrons' is that nothing is supposed to travel faster than the speed of light.
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