Forces From The Particle Viewpoint
When one particle scatters off of another, altering its trajectory, there are two ways to think about the process. In the field picture, we imagine that the field generated by one particle caused a force on the other. Alternatively, we can imagine one particle emitting a virtual particle which is absorbed by the other. The virtual particle transfers momentum from one particle to the other. This particle viewpoint is especially helpful when there are a large number of complicated quantum corrections to the calculation since these corrections can be visualized as Feynman diagrams containing additional virtual particles.
The description of forces in terms of virtual particles is limited by the applicability of the perturbation theory from which it is derived. In certain situations, such as low-energy QCD and the description of bound states, perturbation theory breaks down.
Read more about this topic: Force Carrier
Famous quotes containing the words forces and/or particle:
“The poorest man may in his cottage bid defiance to all the forces of the Crown. It may be frail—its roof may shake—the wind may blow through it—the storm may enter—the rain may enter—but the King of England cannot enter!—all his forces dare not cross the threshold of the ruined tenement!”
—William Pitt, The Elder, Lord Chatham (1708–1778)
“Each particle is a microcosm, and faithfully renders the likeness of the world.”
—Ralph Waldo Emerson (1803–1882)