 Now we take a little leap. If a photon is actually a localized vibrating ripple in the quantized electromagnetic field, why not consider the electron to be a localized vibrating ripple in a quantized matter field? A field that permeates all the space in the universe. This is not as odd as it might look. In our first segment on the microscopic, we saw the wave properties of the electron. And in the second segment on the atom, we saw that its behavior is described by the Schrodinger wave equation. And in our third segment on elementary particles, we saw how electrons and positrons can be materialized at any point in space. What's happening is that the photon has disturbed the electron field to the point that it generates the kinds of waves that constitute electron particles. A convenient way to illustrate elementary particle interactions is to use Feynman diagrams invented by Richard Feynman in 1948. Straight lines are for fermions. Squiggly lines are for force particles, bosons. And the back arrow on a fermion indicates an antiparticle. This is what quantum field theory is all about. These fields generate particles. You can't have a particle without a field. And every field will have its particle. Elementary bosons, force particles, require force fields. Elementary fermions, matter particles, require matter fields. In modern physics, there is no such thing as empty space. Fields pervade space. They are a condition or property of space. You can't have space without fields.