if the particles are farther away from each other, then the vibrations of particles will spread slower
shadow is localized_spatial_thing. vibration is motion. trajectory is localized_spatial_thing. waves is moving_water. electromagnetic_radiation is both_wave_and_particle. fundamental_particle is localized_spatial_thing. photons is both_particles_and_waves. scientists has discovered_particles_far_smaller_than_atoms gravitational_waves is ripples_in_fabric_of_space_time. drop is particle.