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20082025
most citedRigidity of the Alvarez class

8 citations · 28 across the 19 of their papers we have counts for

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11 papers · 1 filter

math.DG2025

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…

math.DG2022

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…

math.DG2015

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…

math.DG2012★ 1 cited

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…

math.DG2012

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…

math.DG2012

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…

math.DG2010★ 1 cited

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…

math.DG2009★ 2 cited

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…

math.DG2009★ 8 cited

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…

math.DG2008★ 1 cited

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…

math.DG2008★ 4 cited

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…