A Comparative Study between K\"ahler and Non-K\"ahler Hyperbolicity
In this note, we establish a connection between SKT and balanced hyperbolicity, highlighting their relationship with K\"ahler hyperbolicity in the sense of Gromov.
math.CV↗
arXiv subjects
Samir Marouani
Publications and source records attributed to Samir Marouani.
SKT Hyperbolic and Gauduchon Hyperbolic Compact Complex Manifolds
We introduce two notions of hyperbolicity for not necessarily K\"ahler even balanced $n$-dimensional compact complex manifolds $X$. The first, called {\it SKT hyperbolicity}, generalises Gromov's K\"ahler hyperbolicity by means of SKT metrics. The second, called {\it Gauduchon hyperbolicity} by means of Gauduchon metrics. Our first main result in this paper asserts that every SKT hyperbolic $X$ is also Kobayashi/Brody hyperbolic and every Gauduchon hyperbolic $X$ is divisorially hyperbolic. The second main result is to prove a vanishing theorem for the $L^2$ harmonic spaces on the universal cover of a SKT hyperbolic manifold.
math.DG↗
Balanced Hyperbolic and Divisorially Hyperbolic Compact Complex Manifolds
We introduce two notions of hyperbolicity for not necessarily Kähler $n$-dimensional compact complex manifolds $X$. The first, called {\it balanced hyperbolicity}, generalises Gromov's Kähler hyperbolicity by means of Gauduchon's balanced metrics. The second, called {\it divisorial hyperbolicity}, generalises the Brody hyperbolicity by ruling out the existence of non-degenerate holomorphic maps from $\C^{n-1}$ to $X$ that have what we term a subexponential growth. Our main result in the first part of the paper asserts that every balanced hyperbolic $X$ is also divisorially hyperbolic. We provide a certain number of examples and counter-examples and discuss various properties of these manifolds. In the second part of the paper, we introduce the notions of {\it divisorially Kähler} and {\it divisorially nef} real De Rham cohomology classes of degree $2$ and study their properties. They also apply to $C^\infty$, not necessarily holomorphic, complex line bundles and are expected to be implied in certain cases by the hyperbolicity properties introduced in the first part of the work. While motivated by the observation of hyperbolicity properties of certain non-Kähler manifolds, all these four new notions seem to have a role to play even in the Kähler and the projective settings.
math.CV↗
Some Properties of Balanced Hyperbolic Compact Complex Manifolds
We prove several vanishing theorems for the cohomology of balanced hyperbolic manifolds that we introduced in our previous work and for the $L^2$ harmonic spaces on the universal cover of these manifolds. Other results include a Hard Lefschetz-type theorem for certain compact complex balanced manifolds and the non-existence of certain $L^1$ currents on the universal covering space of a balanced hyperbolic manifold.
math.CV↗