A proton or a neutron can sometimes "violate" conser- vation of energy by emitting and then reabsorbing a pi meson, which has a mass of 185 MeV/c². This is possi- ble as long as the pi meson is reabsorbed within a short enough time At consistent with the uncertainty principle, (a) Consider p → p + л. By what amount AE is energy conservation violated? (Ignore any kinetic energies.) (b) For how long a time At can the pi meson exist? (c) Assuming that the pi meson travels at very nearly the speed of light, how far from the proton can it go? (This procedure, as we discuss in Chapter 12, gives us an

A proton or a neutron can sometimes "violate" conser- vation of energy by emitting and then reabsorbing a pi meson, which has a mass of 185 MeV/c². This is possi- ble as long as the pi meson is reabsorbed within a short enough time At consistent with the uncertainty principle, (a) Consider p → p + л. By what amount AE is energy conservation violated? (Ignore any kinetic energies.) (b) For how long a time At can the pi meson exist? (c) Assuming that the pi meson travels at very nearly the speed of light, how far from the proton can it go? (This procedure, as we discuss in Chapter 12, gives us an