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Timeline for Electrons on a pancake ellipsoid

Current License: CC BY-SA 3.0

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Apr 13, 2017 at 12:58 history edited CommunityBot
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Jan 2, 2017 at 0:06 comment added Wlodek Kuperberg The perfectly flat pancake (a circular disk) could also be considered, as the limiting case. What would the configurations of a reasonably small numbers $k$ of electrons look like? One can predict some configurations for $k\le 7$ maybe a few beyond $7$. At which value of $k$ lack of symmetry occurs first?
Feb 28, 2016 at 15:35 history edited Joseph O'Rourke CC BY-SA 3.0
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Feb 28, 2016 at 15:21 comment added user21349 The continuous case has been solved for a more general class of shapes that includes oblate ellipsoids. See I W McAllister 1990 J. Phys. D: Appl. Phys. 23 359 doi:10.1088/0022-3727/23/3/016 and math.stackexchange.com/questions/112662/… .
Feb 28, 2016 at 14:54 comment added Yoav Kallus A little Googling came up with this homework problem(?): (physics.princeton.edu/~mcdonald/examples/ellipsoid.pdf), but I haven't checked the calculation. The electrostatic calculation gives the asymptotic density when the number of electrons is very large.
Feb 28, 2016 at 14:44 comment added Manfred Weis For an experimental answer, you might try to obtain such an oblate ellipsoid made metal and then apply some ferrofluid to it youtube.com/watch?v=5APHa7vscoI
Feb 28, 2016 at 14:42 comment added Carlo Beenakker software that will calculate this for you is provided in Charged particles constrained to a curved surface
Feb 28, 2016 at 14:42 comment added Yoav Kallus The answer for minimizing the potential energy (I am assuming a Coulomb potential) and maximizing the minimum distance are going to be very different. The latter gives an asymptotically uniform distribution, while the former will give an uneven distribution with much lower density on the top and bottom. The transition between asymptotic uniformity and nonuniformity is discussed in Hardin and Saff, 2005 dx.doi.org/10.1016/j.aim.2004.05.006
Feb 28, 2016 at 14:32 comment added Manfred Weis Is the ellipsoid an isolator? Would be yet another variant under which the solutions may be different.
Feb 28, 2016 at 13:54 history edited Joseph O'Rourke CC BY-SA 3.0
"flying-saucer" is not as good an analogy as "pancake."
Feb 28, 2016 at 3:01 comment added Gerhard Paseman I was going to suggest capacitor design, but this is a different situation. Nevertheless, you might have some success asking this in an electrical engineering forum, even if they are less concerned with precision. Gerhard "Or Do I Mean Accuracy" Paseman, 2016.02.27.
Feb 28, 2016 at 2:35 history asked Joseph O'Rourke CC BY-SA 3.0