Table of Contents
Fetching ...

$p$-Kähler structures on fibrations and reductive Lie groups

Anna Fino, Gueo Grantcharov, Asia Mainenti

TL;DR

The paper addresses the existence and obstruction of $p$-Kähler and $p$-pluriclosed structures on two main classes: quasi-regular fibrations (notably compact complex homogeneous spaces via the Tits fibration) and invariant complex structures on even-dimensional reductive Lie groups. It develops obstruction criteria based on orbifold line bundle Chern classes and root-system data, showing that under certain positivity and pullback conditions, many fibrations cannot support $(m-j)$-Kähler or $(n-2)$-pluriclosed structures. It then constructs non-regular invariant complex structures on $\mathfrak{sl}(2m-1,\mathbb{R})$ that admit compatible balanced metrics but are not pluriclosed, and contrasts this with a regular family on $\mathfrak{sl}(3,\mathbb{R})$ that also admits balanced metrics. Overall, the results illuminate how algebraic and geometric structures constrain the existence of special Hermitian metrics and provide explicit balanced examples in non-Kähler contexts. These findings advance understanding of the interplay between fibration geometry, Lie-group complex structures, and balanced vs. pluriclosed phenomena.

Abstract

We investigate the existence of $p$-Kähler structures on two classes of complex manifolds: on quasi-regular fibrations, with particular emphasis on complex homogeneous spaces, and on reductive Lie groups endowed with invariant complex structures. In the latter setting, we construct non-regular complex structures on the Lie algebras $\mathfrak{sl}(2m-1,\mathbb{R})$ for $m \ge 2$ and show that these structures admit compatible balanced metrics, providing new explicit examples of balanced manifolds.

$p$-Kähler structures on fibrations and reductive Lie groups

TL;DR

The paper addresses the existence and obstruction of -Kähler and -pluriclosed structures on two main classes: quasi-regular fibrations (notably compact complex homogeneous spaces via the Tits fibration) and invariant complex structures on even-dimensional reductive Lie groups. It develops obstruction criteria based on orbifold line bundle Chern classes and root-system data, showing that under certain positivity and pullback conditions, many fibrations cannot support -Kähler or -pluriclosed structures. It then constructs non-regular invariant complex structures on that admit compatible balanced metrics but are not pluriclosed, and contrasts this with a regular family on that also admits balanced metrics. Overall, the results illuminate how algebraic and geometric structures constrain the existence of special Hermitian metrics and provide explicit balanced examples in non-Kähler contexts. These findings advance understanding of the interplay between fibration geometry, Lie-group complex structures, and balanced vs. pluriclosed phenomena.

Abstract

We investigate the existence of -Kähler structures on two classes of complex manifolds: on quasi-regular fibrations, with particular emphasis on complex homogeneous spaces, and on reductive Lie groups endowed with invariant complex structures. In the latter setting, we construct non-regular complex structures on the Lie algebras for and show that these structures admit compatible balanced metrics, providing new explicit examples of balanced manifolds.
Paper Structure (7 sections, 14 theorems, 40 equations)

This paper contains 7 sections, 14 theorems, 40 equations.

Key Result

Proposition 2.6

A compact complex manifold $(M,J)$ is $p$-Kähler if and only if all strongly positive currents of bidimension $(p,p)$ that are $(p,p)$-components of a boundary are trivial. Similarly, $(M,J)$ is $p$-pluriclosed if and only if all strongly positive currents of bidimension $(p,p)$ that are $(p,p)$-com

Theorems & Definitions (39)

  • Definition 2.1
  • Definition 2.2
  • Definition 2.3: AAAles
  • Definition 2.4
  • Remark 2.5
  • Proposition 2.6: AAAles
  • Theorem 3.1
  • proof
  • Theorem 3.2: Titswang54
  • Corollary 3.3
  • ...and 29 more