From: utzoo!decvax!duke!harpo!seismo!hao!hplabs!hplabsb!soreff Newsgroups: net.physics Title: Truly three dimensional instability Article-I.D.: hplabsb.1268 Posted: Fri Jan 7 18:33:06 1983 Received: Sun Jan 9 01:53:59 1983 Does anyone out there know of an example of a physical system with an instability which truly requires a three dimensional representation or description? I don't mean a system where some vector quantities need components in all three directions, but rather one where for each direction, there is at least one physical function (temperature, electrostatic potential, magnitude of magnetic field strength) which varies along that direction in a way that is qualitatively important to the instability. Basically I am looking for systems which don't have an analog in any system with full translational symmetry in any direction, or with full rotational symmetry about any axis (which would also allow a two dimensional representation). A number of instabilities (those associated with convection, for instance) can produce three dimensional patterns (the hexagonal convection cells, in this instance), but all the ones that I know of have two dimensional analog, so the three-dimensionality of the system only affects the size of critical onset parameters and the like, but not the qualitative instability. I'd like this to be a discussion question, so please post answers to the net. -Jeffrey Soreff (hplabsb!soreff)