5 positivly charged particles on sphere, min energy configuration, rel

AI Thread Summary
The discussion centers on the Thomson Problem, which involves finding the minimum energy configuration of five positively charged particles on the surface of a sphere. Participants explore whether stable configurations exist that are not at minimum energy and suggest using computer simulations to map potential energy surfaces. There is interest in finding more efficient methods to determine the minimum energy configuration beyond random sampling. A triangular dipyramid is identified as a symmetric solution for the configuration, and a Java applet is mentioned for visualizing particle arrangements. The conversation highlights the complexity of the problem, especially as the number of particles increases.
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Assume 5 charged particles (charge 1) constrained to live on the surface of a sphere are in a configuration that minimizes electrostatic potential energy. Are there configurations that are stable but that are not the minimum energy configuration?

A simple computer program could quickly(?) examine many random configurations and slowly map out the potential energy surface E(θ_1,phi_1,θ_2,phi_2,θ_3,phi_3,θ_4,phi_4,θ_5,phi_5)?

There must be more elegant(less computer time) ways to find the minimum energy configuration?

Has this problem been solved?

Edit, E above is a function of only 8 variables, we can always let one particle be at the north pole?Thanks for any help!
 
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Simon Bridge said:
It's called "the Thomson Problem".
http://en.wikipedia.org/wiki/Thomson_problem

Triangular dipyramid :rolleyes: Nice and symmetric, I should have seen that. Things probably get more interesting with larger numbers. From the link above check out a fun Java app at,

http://thomson.phy.syr.edu/thomsonapplet.php

Check out the screen shot and add a charged particle and watch the charges rearrange to I assume the lowest energy configuration. Still would like to know if there are stable relative minimum.

Edit, I think you have to hit the Auto button on the app to get the configuration to minimize energy?

Thanks for your help!
 

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Nice find!
 
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