1. MTU has this wonderful explanation of the differences in physics between open/closed conical and cylindical bore instruments. Try some of the equations out in grapher or an equivalent!

    Open cylindrical bore (e.g. panpipes): y=sin(nx)

    Closed conical bore (e.g. saxophone): y=sin(nx)/nx

    where n is the harmonic e.g. 1, 2, 3, 4 etc. in both cases.

  2. Physics of emotions — some convert easily between each other (e.g. frustration is easy to turn into positive creative energy), others are much harder to change and require significant outside energy (e.g. jadedness)

    Are those even emotions, in the strictest sense? More thought patterns or alignments?