Fear of flying persistent fear or anxiety when they consider flying, as well as during flying. They will avoid flying if they can, and the fear, anxiety, and avoidance cause significant distress and impair their ability to function. Take-off, bad weather, and turbulence appear to be the most anxiety provoking aspects of flying. The most extreme manifestations can include panic attacks or vomiting at the mere sight or mention of an aircraft or air travel. Around 60% of people with fear of flying report having some other anxiety disorder. The causes of flight phobia and the mechanisms by which it is maintained were
Complexity function applicable, which may be taken to be uniformly recurrent or even uniquely ergodic. For "x" a real number and "b" an integer ≥ 2 then the complexity function of "x" in base "b" is the complexity function "p"("x","b","n") of the sequence of digits of "x" written in base "b". If "x" is an irrational number then "p"("x","b","n") ≥ "n"+1; if "x" is rational then "p"("x","b","n") ≤ "C" for some constant "C" depending on "x" and "b". It is conjectured that for algebraic irrational "x" the complexity is "b" (which would follow if all such numbers were normal) but all that