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Related papers: CR embeddings of nilpotent Lie groups

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We obtain an embedding theorem for compact strongly pseudoconvex CR manifolds which are bounadries of some complete Hermitian manifolds. We use this to compactify some negatively curved Kaehler manifolds with compact strongly pseudoconvex…

Complex Variables · Mathematics 2015-09-10 G. Marinescu , N. Yeganefar

We consider locally homogeneous $CR$ manifolds and show that, under a condition only depending on their underlying contact structure, their $CR$ automorphisms form a finite dimensional Lie group.

Differential Geometry · Mathematics 2017-06-13 Stefano Marini , Costantino Medori , Mauro Nacinovich , Andrea Spiro

We classify the germs of $\mathcal{C}^\infty$ CR manifolds that admit a smooth CR contraction. We show that such a CR manifold is embedded into $\CC^n$ as a real hypersurface defined by a polynomial defining function consisting of monomials…

Complex Variables · Mathematics 2011-02-19 Kang-Tae Kim , Jean-Christophe Yoccoz

A complex Lie algebroid is a complex vector bundle over a smooth (real) manifold M with a bracket on sections and an anchor to the complexified tangent bundle of M which satisfy the usual Lie algebroid axioms. A proposal is made here to…

Differential Geometry · Mathematics 2007-05-23 Alan Weinstein

Given any real-analytic CR manifold M, we provide general conditions on M guaranteeing that the group of all its global real-analytic CR automorphisms is a Lie group (in an appropriate topology). Our conditions are in particular satisfied…

Complex Variables · Mathematics 2009-01-12 Bernhard Lamel , Nordine Mir , Dmitri Zaitsev

Let G be compact Lie group. It is shown that the cotangent bundle of the complexification of G admits a hyperkahler structure which is invariant under left and right translations by elements of G. The proof is to realize the cotangent…

Differential Geometry · Mathematics 2007-05-23 P. B. Kronheimer

We classify the nilpotent Lie algebras of real dimension eight and minimal center that admit a complex structure. Furthermore, for every such nilpotent Lie algebra $\mathfrak{g}$, we describe the space of complex structures on…

Rings and Algebras · Mathematics 2022-03-17 Adela Latorre , Luis Ugarte , Raquel Villacampa

We describe a class (called regular) of invariant generalized complex structures on a real semisimple Lie group G. The problem reduces to the description of admissible pairs (\gk, \omega), where \gk is an appropriate regular subalgebra of…

Differential Geometry · Mathematics 2014-02-26 Dmitri V. Alekseevsky , Liana David

For a complex semi-simple Lie algebra, every nilpotent orbit in its projectivization comes with a complex contact structure. For each nilpotent orbit, we classify projective Legendrian subvarieties that are homogeneous under the actions of…

Complex Variables · Mathematics 2026-03-10 Minseong Kwon

This paper investigates some properties of complex structures on Lie algebras. In particular, we focus on $\textit{nilpotent}$ $\textit{complex structures}$ that are characterized by a suitable $J$-invariant ascending or descending central…

Differential Geometry · Mathematics 2022-02-07 Junze Zhang

Pittie [Pit88] proved that the Dolbeault cohomology of all left-invariant complex structures on compact Lie groups can be computed by looking at the Dolbeault cohomology induced on a conveniently chosen maximal torus. We use the algebraic…

Complex Variables · Mathematics 2022-03-29 Howard Jacobowitz , Max Reinhold Jahnke

In this paper we study left invariant CR structures on Lie groups which are compatible with geometric properties as Poisson and kahler properties.

Differential Geometry · Mathematics 2007-05-23 A. Tsemo

We characterise the integrability of any co-CR quaternionic structure in terms of the curvature and a generalized torsion of the connection. Also, we apply this result to obtain, for example, the following. (1) New co-CR quaternionic…

Differential Geometry · Mathematics 2013-05-17 Radu Pantilie

On the basis of a result of Barrett, we show that members of certain classes of abstract Levi flat manifolds with boundary, whose Levi foliation contains a compact leaf with contracting, flat holonomy, admit no $CR$ embedding as a…

Complex Variables · Mathematics 2010-03-09 Giuseppe Della Sala

We consider canonical fibrations and algebraic geometric structures on homogeneous CR manifolds, in connection with the notion of CR algebra. We give applications to the classifications of left invariant CR structures on semisimple Lie…

Differential Geometry · Mathematics 2010-12-20 Andrea Altomani , Costantino Medori , Mauro Nacinovich

Gromov claimed, with a sketch of proof, that simply connected nilpotent Lie groups have polynomially bounded filling invariants. The literature establishes this, often with a stronger conclusion where the exponent of polynomiality is…

Group Theory · Mathematics 2026-03-30 Gabriel Pallier

This paper completes the classification of seven-dimensional nilpotent Lie groups endowed with a left-invariant purely coclosed $\text{G}_2$-structure, initiated by the first-named author and collaborators. In this previous work, the…

Differential Geometry · Mathematics 2025-10-30 Giovanni Bazzoni , Giorgia Petracci

We prove that every compact, pseudoconvex, orientable, CR manifold of $\C^n$, bounds a complex manifold in the $C^\infty$ sense. In particular, the tangential Cauchy-Riemann system has closed range.

Complex Variables · Mathematics 2017-07-12 Luca Baracco

We study complex product structures on nilpotent Lie algebras, establishing some of their main properties, and then we restrict ourselves to 6 dimensions, obtaining the classification of 6-dimensional nilpotent Lie algebras admitting such…

Differential Geometry · Mathematics 2007-05-23 Adrian Andrada

Let $i:X\hookrightarrow Y$ be a closed embedding of smooth algebraic varieties. Denote by $N$ the normal bundle of $X$ in $Y$. We describe the construction of two Lie-type structures on the shifted bundle $N[-1]$ which encode the…

Algebraic Geometry · Mathematics 2014-07-01 Damien Calaque , Andrei Caldararu , Junwu Tu