1 citations · 2 across the 4 of their papers we have counts for
5 papers
Group cocycles on the volume-preserving diffeomorphism group
Shuhei Maruyama
We construct two kinds of group cocycles on the volume-preserving diffeomorphism group. We show that, for the volume-preserving diffeomorphism group of the sphere, one of the cocyc…
Extensions of quasi-morphisms to the symplectomorphism group of the disk
Shuhei Maruyama
On the group of symplectomorphisms of the disk which are the identity near the boundary, there are homogeneous quasi-morphisms called the Ruelle invarian…
A note on stable commutator length in braided Ptolemy-Thompson groups
Shuhei Maruyama
In this note, we show that the sets of all stable commutator lengths in the braided Ptolemy-Thompson groups are equal to non-negative rational numbers.
The translation number and quasi-morphisms on groups of symplectomorphisms of the disk
Shuhei Maruyama
On groups of symplectomorphisms of the disk, we construct two homogeneous quasi-morphisms which relate to the Calabi invariant and the flux homomorphism respectively. We also show…
The flux homomorphism and central extensions of diffeomorphism groups
Shuhei Maruyama
Let be a 2-dimensional closed unit disk and the group of symplectomorphisms preserving the origin and the boundary pointwise. We consid…