Bavard's duality theorem on conjugation-invariant norms
arXiv:1606.01961 · doi:10.2140/pjm.2017.288.157
Abstract
Bavard proved a duality theorem between commutator length and quasimorphisms. Burago, Ivanov and Polterovich introduced the notion of a conjugation-invariant norm which is a generalization of commutator length. Entov and Polterovich proved that Oh-Schwarz spectral invariants are subset-controlled quasimorphisms which are geralizations of quasimorphisms. In the present paper, we prove a Bavard-type duality theorem between conjugation-invariant (pseudo-)norms and subset-controlled quasimorphisms on stable groups. %We also give an application of its generalization to symplectic geometry related to Entov-Polterovich's theory on heavy subsets. We also pose a generalization of our main theorem and prove that "stably non-displaceable subsets of symplectic manifolds are heavy" in a rough sense if that generalization holds.
11 pages, the referred paper "Conjugation-invariant norms on the commutator subgroup of infinite braid group" is accepted and so I correct the reference. I would like to congratulate on the first acceptance experience of my junior disciple, to appear in Pacific Journal of Mathematics