Zobrazeno 1 - 10
of 90
pro vyhledávání: '"Kamishima, Yoshinobu"'
Autor:
Baues, Oliver, Kamishima, Yoshinobu
In this expository paper we discuss several properties on closed aspherical parabolic ${\sfG}$-manifolds $X/\Gamma$. These are manifolds $X/\Gamma$, where $X$ is a smooth contractible manifold with a parabolic ${\sfG}$-structure for which $\Gamma\leq
Externí odkaz:
http://arxiv.org/abs/2309.13569
Autor:
Baues, Oliver, Kamishima, Yoshinobu
We establish that for any proper action of a Lie group on a manifold the associated equivariant differentiable cohomology groups with coefficients in modules of $\mathcal{C}^\infty$-functions vanish in all degrees except than zero. Furthermore let $G
Externí odkaz:
http://arxiv.org/abs/2101.03831
Autor:
Baues, Oliver, Kamishima, Yoshinobu
Let $G/H$ be a contractible homogeneous Sasaki manifold. A compact locally homogeneous aspherical Sasaki manifold $\Gamma\big\backslash G/H$ is by definition a quotient of $G/H$ by a discrete uniform subgroup $\Gamma\leq G$. We show that a compact lo
Externí odkaz:
http://arxiv.org/abs/1906.05049
Autor:
Kamishima, Yoshinobu
We study positive definite quaternionic contact $(4n+3)$-manifolds ($qc$-manifold for short). Just like the $CR$-structure contains the class of Sasaki manifolds, the $qc$-structure admits a class of $3$-Sasaki manifolds with integrable distribution
Externí odkaz:
http://arxiv.org/abs/1902.08796
Publikováno v:
Nagoya Mathematical Journal, 08 November (2019), pp. 1-14
A Vaisman manifold is a special kind of locally conformally Kaehler manifold, which is closely related to a Sasaki manifold. In this paper we show a basic structure theorem of simply connected homogeneous Sasaki and Vaisman manifods of unimodular Lie
Externí odkaz:
http://arxiv.org/abs/1810.01095
Autor:
Baues, Oliver, Kamishima, Yoshinobu
Publikováno v:
Geom. Topol. 27 (2023) 1-50
Every compact aspherical Riemannian manifold admits a canonical series of orbibundle structures with infrasolv fibers which is called its infrasolv tower. The tower arises from the solvable radicals of isometry group actions on the universal covers.
Externí odkaz:
http://arxiv.org/abs/1810.00228
Autor:
Baues, Oliver, Kamishima, Yoshinobu
Publikováno v:
In Differential Geometry and its Applications June 2020 70
Publikováno v:
International Journal of Mathematics, Vol. 26 (06), 1-29 (2015)
We prove various classification results for homogeneous locally conformally symplectic manifolds. In particular, we show that a homogeneous locally conformally Kaehler manifold of a reductive group is of Vaisman type, if the normalizer of the isotrop
Externí odkaz:
http://arxiv.org/abs/1403.3268
Autor:
Hasegawa, Keizo, Kamishima, Yoshinobu
Publikováno v:
Osaka Journal of Mathematics, Vol. 53, No. 3 (2016)
In this paper we show as main results two structure theorems of a compact homogeneous locally conformally Kaehler (or shortly l.c.K.) manifold, a holomorphic structure theorem asserting that it has a structure of holomorphic principal fiber bundle ov
Externí odkaz:
http://arxiv.org/abs/1312.2202
Autor:
Kamishima, Yoshinobu
If an $m+2$-manifold $M$ is locally modeled on $\RR^{m+2}$ with coordinate changes lying in the subgroup $G=\RR^{m+2}\rtimes ({\rO}(m+1,1)\times \RR^+)$ of the affine group ${\rA}(m+2)$, then $M$ is said to be a \emph{Lorentzian similarity manifold}.
Externí odkaz:
http://arxiv.org/abs/1110.1792