3 papers
math.SG2025
Flux homomorphism and bilinear form constructed from Shelukhin's quasimorphism
Morimichi Kawasaki, Mitsuaki Kimura, Shuhei Maruyama +2
Given a closed connected symplectic manifold , we construct an alternating -bilinear form on the real first cohomol…
math.SG2025
Non-extendablity of Shelukhin's quasimorphism and non-triviality of Reznikov's class
Morimichi Kawasaki, Mitsuaki Kimura, Shuhei Maruyama +2
Shelukhin constructed a quasimorphism on the universal covering of the group of Hamiltonian diffeomorphisms for a general closed symplectic manifold. In the present paper, we prove…
math.GR2024
Relative simplicity of the universal coverings of transformation groups and Tsuboi's metric
Morimichi Kawasaki, Mitsuaki Kimura, Hiroki Kodama +3
Many transformation groups on manifolds are simple, but their universal coverings are not. In the present paper, we study the concept of relatively simple group, that is, a group w…