Notes on Feynman stuff


concepts to be taught:

(a) can't say how a process got from start to finish
(b) all ways for a process to occur are relevant, KEY CONCEPT
(c) hidden variable in addition to probability for a process, phase, KEY CONCEPT
(d) phase can only be measured indirectly
(e) classical mechanics limiting case of quantum mechanics
(f) small set of paths actually relevant compared to large number of possible paths
(g) relay my personal method of thinking... once localized a particle spreads out as goes over all paths, WORDS ONLY
(h) in single slit probability distribution is roughly constant... phase is not constant
(i) multiple slit causes interference patters, even though paths exist to those regions of zero probability
(j) phase/probability at each slit initially relevant to final distribution
(k) summing over certain selected paths yields strange results
(l) also a phase corresponding to each path


terms:

process - going from some initial to some final state, ex. electron starting at slit and ending at a point on the screen
path - a particular way that some process can happen
phase - each process has a probability and a second parameter, phase, paths have only phase


1st level: single slit, fixed endpoint, vary only path selection, choose individually or sum over various regular sets
concepts demonstrated: (a), (b), (e), (f), (k), (l)

2nd level: single slit, sum over full set of paths, vary endpoint
concepts demonstrated: (a), (b), (c), (h)

3rd level: double slit, sum over full set for each path individual as vary endpoint, sum over both full sets as vary endpoint
concepts demonstrated: (b), (c), (d), (i)

4th level: vary slit location and probability/phase for each slit, sum over all paths through each slit as endpoint varies
concepts demonstrated: (b), (i), (j)

5th level: vary everything
concepts demonstrated: all