Not even close. The diameter of the electron is under 10^-18 meters -- that's a sort of experimental upper bound derived from collision experiments -- but it m

Not even close. The diameter of the electron is under 10^-18 meters -- that's a sort of experimental upper bound derived from collision experiments -- but it may well be much smaller than that. Some estimates for the diameter of the electron approach the Planck length -- and some, which are no less credible, are well under the Planck length, e.g. at 10^-80m. In physics, the electron is usually described as a point with no size at all. Thus, for practical intents and purposes, it exists but is infinitely small. (Which sort of reflects the notion that human physics is an idealization of the natural world.) The Planck length isn't a hard physical limit for size. It's where direct measurement starts running into insurmountable barriers.