Electrons always move because they are only one-dimensional matter, so photons can fill their other dimensions to cause movement. The matter-photon hybrid is held together because quantum entanglement unifies entities that restart at the same point. Electrons then always move, as light does, but are light-like on only two dimensions as one dimension is matter-like, so are slower.
In contrast, when quarks combine into atoms, the distribution is symmetric, so they don’t naturally move as electrons do. Yet quarks still have free channels for photons to occupy, as their higher generations show, so atoms can acquire extra photons to move as electrons do. Light hitting a solar sail then moves it because its matter absorbs photons that bias the quantum field around it in their direction. The sail matter is already trembling in all directions, so adding photons that increase that tremble one way make it move.
The alternative that photon particles push the sail struggles because photons have no mass, so energy is said to cause momentum, but relativistic mass is a troublesome concept in physics. The simpler view is that the sail moves when its quantum field changes, not because particles push it.
Adding photons also explains why mass increases as objects go faster, as more competition for channels produces more interference, which increases the processing that in this model is mass. The increase isn’t linear because interference doesn’t increase linearly with load, as networks like the Internet show. Mass then increases as movement increases, as relativity states.
This also explains inertia, the tendency of matter to keep on moving, because when matter acquires photons that make it move, they stay with it, so it carries on moving the same way.
That matter can acquire photons explains how it moves but not how gravity works, so how does a large mass like the earth move the matter around it, even at great distances?