Nearby exact Lagrangian intersection lemma (source code)

= Nearby exact Lagrangian intersection lemma

If a compact Lagrangian $L$ has $H^1(L;\mathbb R)=0$, every sufficiently close Lagrangian graph is the graph of $df$ and meets the zero section at least at a maximum and a minimum of $f$. Without the cohomology assumption, a nowhere-zero closed one-form can give a disjoint nearby graph.