Okay, time to geek out a bit. I feel guilt for both doing so, and using the term "geeking out" but what can you do? Suffer with me.
For those of you who know of the Large Hadron Collider, you know it is big. 17 Miles big. Underground. A friend of mine once visited the site and the stories were otherworldly. Luckily, National Geographic (an odd choice of publications for servicing us with physics news, no?) provides us with a brief look into that world. [P.S. what a wonderfully designed site. Note the simple navigation at the top, the clean white-space design - webmasters take note]At the Heart of All Matter
- please don't mind me for quoting, specifically, Rutherford, of McGill fame:
Was it, as [J.J.] Thomson believed, a pudding, with electrons embedded like raisins? No. In 1911 physicist Ernest Rutherford announced that atoms are mostly empty space, their mass concentrated in a tiny nucleus orbited by electrons.
I digress, on to the good stuff:
There must be some exotic hidden matter in the mix. A theory called supersymmetry could account for this: It states that every fundamental particle had a much more massive counterpart in the early universe. The electron might have had a hefty partner that physicists refer to as the selectron. The muon might have had the smuon. The quark might have had ... the squark. Many of those supersymmetric partners would have been unstable, but one kind may have been just stable enough to survive since the dawn of time. And those particles might, at this very second, be streaming through your body without interacting with your meat and bones. They might be dark matter.
Then we get the worst analogy in the world:
[Theoretical physicist John Ellis of CERN] offers an analogy: Different fundamental particles, he says, are like a crowd of people running through mud. Some particles, like quarks, have big boots that get covered with lots of mud; others, like electrons, have little shoes that barely gather any mud at all. Photons don't wear shoes—they just glide over the top of the mud without picking any up.
*Sigh*.. Nevertheless, it's an interesting piece and gives a tiny view into the big world of colliders in general. Have a look.