I thank Greg Hakim, Riwal Plougonven, Chris Snyder, Jacques Vanneste, Álvaro Viúdez, and Djoko Wirosoetisno for showing me pre-publication versions of their work and for many useful comments, and Tim Dunkerton and Pascale Lelong for their vision in organizing such a timely and stimulating First Workshop on Spontaneous Imbalance and for funding assistance. Djoko Wirosoetisno contributed recent insights into the mathematical issues, which in diffusive versions of these problems involve the extremely smooth behavior known as Gevrey regularity.
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