Episode 036 - Anne Hofmeister on Galactic Rotation, Math, and Glass

The times below are continuations from the last episode. My opening is about 1:30, and then we start with galaxy motions at "26:00". 26:00 Galaxy motions 27:00 Galaxy rotation curves: do not match Keplerian orbits 28:00 Galaxies spin more like records (laggy soft records); mass distribution is nothing like the Solar System 29:00 Hurricanes as a better analogy for galaxies 30:00 Stars in a galaxy move in local organization 32:00 Nebulas 34:00 The opposite extreme: rigid body rotation 35:00 Gravitational attraction between stars creating coherence 36:00 Curiosity that gravity and electrical forces are both inverse square laws 37:00 Poisson's equation 38:00 Summing densities in Poisson's inhomogeneous term is physically meaningless; intensive quantities can't be summed that way 40:00 Gauss' theorem: flux through a surface and quantity within a volume 41:00 Summing is for extensive variables 42:00 Pressure an ambiguous variable 43:00 Future work 44:00 Thermal expansivity: Giauque 45:00 Problems with the glass transition measurements done in the past: need to completely drive out water from the experimental charges 48:00 Wrapup