8 citations · 28 across the 19 of their papers we have counts for
23 papers
Rigidity of Lie foliations with locally symmetric leaves
Gael Meigniez, Hiraku Nozawa
We prove that if the leaves of a minimal Lie foliation are locally isometric to a symmetric space of non-compact type without a Poincare disk factor, then the foliation is smoothly…
Harmonic measures and rigidity for transverse foliations on Seifert -manifolds
Masanori Adachi, Yoshifumi Matsuda, Hiraku Nozawa
Thurston proposed, in part of an unfinished manuscript, to study surface group actions on by using an -connection on the suspension bundle obtained from a harmonic measu…
On statistics which are almost sufficient from the viewpoint of the Fisher metrics
Kaori Yamaguchi, Hiraku Nozawa
A statistic on a statistical model is sufficient if it has no information loss, namely, the Fisher metric of the induced model coincides with that of the original model due to Kull…
Harmonic measures and rigidity for surface group actions on the circle
Masanori Adachi, Yoshifumi Matsuda, Hiraku Nozawa
We study rigidity properties of actions of a torsion-free lattice of on the circle . We follow the approaches of Frankel and Thurston proposed in pre…
Generalized Bishop frames on curves on E^4
Hiraku Nozawa, Subaru Nomoto
We introduce and study generalized Bishop frames on regular curves, which are generalizations of the Frenet and Bishop frames for regular curves on higher dimensional spaces. There…
On a classification of irreducible periodic diffeomorphisms on surfaces which commute with certain involution
Norihisa Takahashi, Hiraku Nozawa
Ishizaka classified up to conjugacy hyperelliptic periodic automorphisms of a surface. Here, an involution on a surface is hyperelliptic if and only if $Σ_{g}/\langle I…
Wild Cantor actions
Jesús Álvarez López, Ramón Barral Lijó, Olga Lukina +1
The discriminant group of a minimal equicontinuous action of a group on a Cantor set is the subgroup of the closure of the action in the group of homeomorphisms of , con…
Coarse distinguishability of graphs with symmetric growth
Jesús Antonio Álvarez López, Ramón Barral Lijó, Hiraku Nozawa
Let be a connected, locally finite graph with symmetric growth. We prove that there is a vertex coloring and some such that every automor…
Dehn twist presentations of hyperelliptic periodic diffeomorphisms on closed surfaces
Norihisa Takahashi, Hiraku Nozawa
We classify up to conjugacy the group generated by a commuting pair of a periodic diffeomorphism and a hyperelliptic involution on an oriented closed surface. This result can be vi…
Chaotic Delone sets
Jesús Antonio Álvarez López, Ramón Barral Lijó, John Hunton +2
We present a definition of chaotic Delone set, and establish the genericity of chaos in the space of -Delone sets for . We also present a hyperbolic analogue of the…
Genericity of chaos for colored graphs
Ramón Barral Lijó, Hiraku Nozawa
To each colored graph, one can associate its closure in the universal space of isomorphism classes of pointed colored graphs, and this subspace can be regarded as a generalized sub…
Localization of Chern-Simons type invariants of Riemannian foliations
Oliver Goertsches, Hiraku Nozawa, Dirk Toeben
We prove an Atiyah-Bott-Berline-Vergne type localization formula for Killing foliations in the context of equivariant basic cohomology. As an application, we localize some Chern-Si…
Haefliger cohomology of complete Riemannian foliations
Hiraku Nozawa
Haefliger cohomology characterizes taut foliated manifolds by Haefliger's theorem. We show that Haefliger cohomology characterizes strongly tense foliated manifolds, namely, foliat…
Rigidity and vanishing of basic Dolbeault cohomology of Sasakian manifolds
Oliver Goertsches, Hiraku Nozawa, Dirk Toeben
The basic Dolbeault cohomology groups of a Sasakian manifold M are invariants of its characteristic foliation F (the orbit foliation of the Reeb flow). We show some fundamental pro…
Tenseness of Riemannian flows
Hiraku Nozawa, José Ignacio Royo Prieto
We show that any transversally complete Riemannian foliation F of dimension one on any possibly non-compact manifold M is tense; namely, (M,F) admits a Riemannian metric such that…
Secondary characteristic classes of transversely homogeneous foliations
Jesús A. Álvarez López, Hiraku Nozawa
Let G be a simple Lie group of real rank one, and S the ideal boundary of the corresponding symmetric space of noncompact type (H^n_R, H^n_C, H^n_H or H^2_O). We show the finitenes…
Equivariant cohomology of K-contact manifolds
Oliver Goertsches, Hiraku Nozawa, Dirk Toeben
We investigate the equivariant cohomology of the natural torus action on a K-contact manifold and its relation to the topology of the Reeb flow. Using the contact moment map, we sh…
Continuity of the Alvarez class under deformations
Hiraku Nozawa
A foliated manifold (M,F) is minimizable if there exists a Riemannian metric g on M such that every leaf of F is a minimal submanifold of (M,g). Alvarez Lopez defined a cohomology…
Minimizability of developable Riemannian foliations
Hiraku Nozawa
Let (M,F) be a closed manifold with a Riemannian foliation. We show that the secondary characteristic classes of the Molino's commuting sheaf of (M,F) vanish if (M,F) is developabl…
Rigidity of the Alvarez class
Hiraku Nozawa
Let be a closed manifold with a Riemannian foliation. The Álvarez class is the cohomology class of degree 1 of whose triviality characterizes the minimizabili…
Five dimensional K-contact manifolds of rank 2
Hiraku Nozawa
A K-contact manifold is a smooth manifold M with a contact form whose Reeb flow preserves a Riemannian metric on M. Main examples are Sasakian manifolds. Our results in this paper…
Rigidity of the Álvarez classes of Riemannian foliations with nilpotent structure Lie algebras
Hiraku Nozawa
We show that if the structure algebra of a Riemannian foliation F on a closed manifold M is nilpotent, then the integral of the Álvarez class of (M,F) along every closed path is th…
Deformation of Sasakian metrics
Hiraku Nozawa
Deformations of the Reeb flow of a Sasakian manifold as transversely Kähler flows may not admit compatible Sasakian metrics anymore. We show that the triviality of the (0,2)-compon…