&gt; Turbulence seems to be very weird.<p>Right up there with &quot;the Riemann hypothesis is quite difficult.&quot;  (Of course, probably nothing beats the irony in naming of the Fundamental Lemma (<a href="https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Fundamental_lemma_%28Langlands_program%29" rel="nofollow">https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Fundamental_lemma_%28Langlands...</a>).)