2 citations · 3 across the 6 of their papers we have counts for
6 papers
Quasi-isometry type of the metric space derived from the kernel of the Calabi homomorphism
Tomohiko Ishida
We prove that the set of symmetrized conjugacy classes of the kernel of the Calabi homomorphism on the group of area-preserving diffeomorphisms of the -disk is not quasi-isometr…
Orderings of Witzel-Zaremsky-Thompson groups
Tomohiko Ishida
We prove the orderability of the Witzel-Zaremsky-Thompson group for a direct system of orderable groups under a certain compatibility assumption.
A twisted first homology group of the handlebody mapping class group
Tomohiko Ishida, Masatoshi Sato
Let be a 3-dimensional handlebody of genus . We determine the twisted first homology group of the mapping class group of with coefficients in the first integral…
Homomorphisms on groups of volume-preserving diffeomorphisms via fundamental groups
Tomohiko Ishida
Let be a closed manifold. Polterovich constructed a linear map from the vector space of quasi-morphisms on the fundamental group of to the space of quasi-morphis…
Quasi-morphisms on the group of area-preserving diffeomorphisms of the 2-disk via braid groups
Tomohiko Ishida
Recently Gambaudo and Ghys proved that there exist infinitely many quasi-morphisms on the group of area-preserving diffeomorphisms of the…
The Lie algebra of rooted planar trees
Tomohiko Ishida, Nariya Kawazumi
We study a natural Lie algebra structure on the free vector space generated by all rooted planar trees as the associated Lie algebra of the nonsymmetric operad (non- operad, pre…