Article Contents
Article Contents

# The gap between near commutativity and almost commutativity in symplectic category

• On any closed symplectic manifold of dimension greater than $2$, we construct a pair of smooth functions, such that on the one hand, the uniform norm of their Poisson bracket equals to $1$, but on the other hand, this pair cannot be reasonably approximated (in the uniform norm) by a pair of Poisson commuting smooth functions. This comes in contrast with the dimension $2$ case, where by a partial case of a result of Zapolsky [13], an opposite statement holds.
Mathematics Subject Classification: Primary: 53D99.

 Citation:

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