Middle and High School … from a Montessori Point of View
LiveScience has a neat little slideshow that briefly describes the different types of elementary particles. These include the particles, like quarks that make up protons, which have been observed, as well as sparticles and the Higg’s boson that have not.
CERN also has a nice page describing the Standard Model.
When it comes to particle physics … [m]easuring something once is meaningless because of the high degree of uncertainty involved in such exotic, small systems. Scientists rely on taking measurements over and over again — enough times to dismiss the chance of a fluke.
— Moskowitz (2011): Is the New Physics Here? Atom Smashers Get an Antimatter Surprise in LiveScience
New research, out of the Large Haldron Collider in Switzerland, shows a 0.8% difference in the way matter and antimatter particles behave. This small difference could go a long way in explaining why the universe is made up mostly of matter today, even though in the beginning there were about equal amounts of matter and antimatter. It would mean that the current, best theory describing particle physics, the Standard Model, needs some significant tweaking.
0.8% is small, but significant. How confident are the physicists that their measurements are accurate? Well, the more measurements you take the more confident you can be in your average result, though you can never be 100% certain. The LHC scientists did enough measurements that they could calculate, statistically, that there is only a 0.05% chance that their measurement is wrong.
Physicists at CERN believe they’ve measured neutrinos moving faster than the speed of light. Since most of modern physics is based on the speed of light being the upper speed limit for practically everything, (remember, in E=mc2, c is the speed of light) this is somewhat of a big deal. NPR has an article:
1. Neutrinos themselves are quite fascinating and elusive particles. Sciencemadefun has a nice video explaining what is a neutrino.
2. Victor Stenger provides an interesting perspective on these results. He points out that the theoretical particles, tachyons, move faster than light, but they can’t move slower than light, so, seen from the point of view of a tachyon, time would move backward. Only photons move at the speed of light.