What about masses?
Another disturbing feature of the Standard Model is that many fundamental
interactions aren't explained by the theory. For example, why is the W
particle is very massive and the photon massless, if both are force carriers?
What causes the generation and distribution of particle mass?
To explain this gap in the Standard Model theory, physicists have theorized
the existence of a particle called the Higgs boson, which has not yet been proven to exist. This particle supposedly interacts with other particles in a way demonstrated by the Higgs Mechanism.
This picture isn't real. As far as we know, neither W's nor photons have size -- they just have different masses.