Endnotes
Note 7: Why atoms can’t be photographed
- Quote: Cells can be photographed using a microscope. That won’t work for atoms, so tiny that visible light can’t bounce off them effectively.
- Endnote: Visible light’s waves have crests and troughs much wider than atoms, so a flash of visible light can no more reflect off a single atom than ocean waves can reflect off a pebble.
- Discussion
Note 12: Antiparticles
- Quote: The up quark’s antiparticle is the up anti-quark. Consequently, the up anti-quark’s antiparticle is the up quark. Similarly, the down quark’s antiparticle is the down anti-quark, and vice versa.
- Endnote: Notice that we do not say that “up quarks are particles and up anti-quarks are antiparticles”; that would be incorrect. They are each other’s antiparticles.
- Discussion [and see also my older article on the subject, which has a link to even more detailed discussion.]
Note 13: Conserving quarks
- Quote: In the sense of physics dialect, the number of quarks minus the number of anti-quarks is conserved. And so, once an object with three extra quarks has somehow been formed, the number of its extra quarks never grows or shrinks and forever remains three, unless and until the object is destroyed.
- Endnote: The weak nuclear force can interconvert up quarks and down quarks and is responsible for processes that change protons into neutrons (and vice versa), such as occur in stellar furnaces. The strong nuclear force leaves quark type unchanged and thus keeps protons as protons and neutrons as neutrons. Both preserve quark number minus anti-quark number, a conservation law that holds in all experiments so far, though it is expected to fail to a tiny degree.
- Discussion
Note 14: The proton phib
- Quote: Considering all this complexity, you can understand why the proton phib has survived; it’s a quick sound bite, whereas the truth requires several pages.
- Endnote: There’s a second reason: it works quite well in predicting certain experimental results, for surprising reasons involving sophisticated math. There may perhaps be a third reason regarding the proton’s internal structure.
- Discussion
Note 16: Activity and stability in protons
- Quote: Such collisions and transformations are happening continuously and stably inside protons and neutrons. They are completely benign, cause no damage, and always conserve the number of extra quarks.
- Endnote: It is not at all obvious that a proton could have so much inner activity and yet preserve outward stability. In fact, it is possible only because of quantum physics. Atoms have this property, too; quantum physics allows electrons both to surround a nucleus in a static manner and yet to maintain considerable motion.
- Discussion
