Class 8

Notes index

Class 6

Origin of the Universe - Class 7

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Questions from homework 5:

1. How quantum theory solves the problems of "infinite density" and "radiative collapse" of atoms.
2. Spin, especially spin 1/2. Angular momentum.
3. Antimatter. We can make it and use it (as in PET), but it is rare in nature. Why?
4. All neutrinos are left-handed (in the Standard Model). Parity is strongly violated in this case.
5. Virtual particles and "real" particles.
6. The "color charge" of quarks is not real color. It is a property that, in some ways, behaves like our perception of color.
7. The strong force between two quarks increases with distance, while the electric force decreases. At 3*10^-17 m, the strong force between two u quarks is 60 times the electric force, but at 10^-18 m it is 25 times. See particle chart, part of The Particle Adventure at http://pdg.lbl.gov/cpep.html.

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