We Have No Idea: A Guide to the Unknown Universe

by Jorge Cham

The idea that the Higgs boson might exist came out of studying the patterns of the particles that transmit forces—the photon, the W boson, and the Z boson—and asking questions about their mass. Physicists asked: Why is one of them massless (the photon) and the others (W and Z) very massive? It didn’t make sense in this particular case for this strange label that we call mass to be zero for one force particle and yet be nonzero for the others. Peter Higgs and several other particle physicists stared at this for a while until they found the solution: just make stuff up. Literally. They posited that if you add one more particle (the Higgs boson) and its field (the Higgs field) to the equations then mass as a particle label—and why some particles have it more than others—start to make sense. Roughly, the theory goes like this: imagine a field that permeates the entire universe. This field does something no other field does: rather than attracting or repelling anything, it makes it hard for particles to get going or slow down. The effect of this field is identical to the effect of having inertial mass.