Shadowing Lemma

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A curious creature that exists in only two dimensions, and eats mathematicians. Parodies the words lamina, a 2-dimensional mathematical object, and lemma, a mathematical theorem used to prove other theorems. There is also a whiff of Lemming about it - a real creature with a mythical need for self-harm.


Shadowing Lemmas exist on Roundworld too, but not as mathematician-eating creatures, more's the pity. Shadowing describes the situation where a true orbit of a dynamical system such as a differential equation or a map lies uniformly near (that is, shadows) a pseudo (or approximate) orbit. The shadowing lemma for discrete dynamical systems has been described in Barreto (2008). In this entry the analogous results for continuous dynamical systems, that is, flows, are described.

No, I don't get it either.