A chance encounter at a July 4 picnic made the latest development in particle physics seem much more comprehensible. Here's what I learned.
So I was at a July 4 picnic on Wednesday where one of the other guests used to be a physics teacher at Stuyvesant High School, and he explained this whole Higgs boson thing to me in a way that made it make about as much sense as it's going to for someone who only took physics in college. And he did the whole thing without using food metaphors -- molasses, soup, etc. -- which I thought was impressive.
Basically, it's like this: Sub-atomic particles are either fermions or bosons. Fermions are the things you learned about in high school physics -- electrons, protons, neutrons and so on -- that share the quality that you can't have two of them in the same space on an atom. Think of them as the billiard balls: they can be all over the table, but not in the same space at the same time, and where they go is determined by the size of the tables. Most of the widely-known fermions are composites made up of other categories of sub-atomic particles, like quarks (which combine to form protons) and leptons, but the most important thing to know about them for the purposes of this discussion is that they are considered the matter particles.
Bosons are different. Bosons have the capacity to share space because they are more like a force than a thing in the way we normally think of "things" or "particles." And since the normal understanding of the word particle is that it's a small thing that has matter -- the mote in the sun, rather than the light itself -- perhaps a better way for lay people to think of bosons is as entities that have effects; they carry the forces (strong, weak, gravitational or electromagnetic) described by the Standard Model in physics, making them what physicists call force-carrying particles.
But if this whole particle-that-lacks-mass thing is still tripping you up, you don't need to use that word in your own head; bosons lose nothing for our purposes by being thought of as entities, even if they are still technically particles, which is to say something really small of which other things are made. Some bosons have mass and some don't. The Higgs boson has a very large mass for a sub-atomic particle, though of course it is still sub-atomic, which is to say tiny.
There are an array of different kinds of bosons, of which the Higgs boson is only the latest to be (tentatively) confirmed as existing. Here are some of the other kinds of bosons:
* Gluons. So named -- seriously -- because they help glue quarks together, mass-less gluons carry the strong force but operate only at close range, like glue, in that glue will stick two adjacent things together but not attract something from the other side of the room.
* W and Z bosons. W and Z bosons carry the weak force and operate at close range.
* Photons. Photons are mass-less wave-like particles that are the basic building blocks of light and carry the electromagnetic force.