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Structural stability addendum

It may also be a guiding principle of modeling that models of ill-reproducible phenomena should be in terms of structurally unstable models. See G. C. Pacquette and Y. Oono, “Structural stability and selection of propagating fronts in semilinear parabolic partial differential equations,” Phys. Rev. E  49 , 2368-2388 (1994).

Footnote 47 Comments on the structural stability of chaos.

As is noted here, if the structural perturbation is only C^0 close, obviously chaos can be immediately destroyed. 

Footnote 48 Functional analytical nature of the Navier-Stokes equation