English
Related papers

Related papers: CR Embeddings, Chains, and the Fefferman Bundle

200 papers

In this {paper}, we consider holomorphic embeddings of $Gr(2,m)$ into $Gr(2,n)$. We study such embeddings by finding all possible total Chern classes of the pull-back of the universal bundles under these embeddings. Using the relations…

Algebraic Geometry · Mathematics 2017-02-16 Minhyuk Kwon

An ultrametric topology formalizes the notion of hierarchical structure. An ultrametric embedding, referred to here as ultrametricity, is implied by a hierarchical embedding. Such hierarchical structure can be global in the data set, or…

Methodology · Statistics 2011-01-11 Fionn Murtagh

When identified with sequences of irreducible Hermitian-Einstein connections, sequences of stable holomorphic bundles of fixed topological type and bounded degree on a compact complex surface equipped with a Gauduchon metric are shown to…

alg-geom · Mathematics 2008-02-03 Nicholas P. Buchdahl

Beginning with a review of the arguments leading to the so-called c=1 barrier in the continuum formulation of noncritical string theory, the pathology is then exhibited in a discretized version of the theory, formulated through dynamical…

High Energy Physics - Theory · Physics 2007-05-23 Parthasarathi Majumdar

We show that the Poincar\'e bundle gives a fully faithful embedding from the derived category of a curve of sufficiently high genus into the derived category of its moduli space of bundles of rank $r$ with fixed determinant of degree 1.…

Algebraic Geometry · Mathematics 2019-09-17 Pieter Belmans , Swarnava Mukhopadhyay

In this paper, projective representations of generalized chain geometries are investigated, using the concepts and results of part I. In particular, we study under which conditions such a projective representation maps the chains of a…

Algebraic Geometry · Mathematics 2024-02-13 Andrea Blunck , Hans Havlicek

Let M be a compact Sasakian manifold. We show that M admits a CR-embedding into a Sasakian manifold diffeomorphic to a sphere, and this embedding is compatible with the respective Reeb fields. We argue that a stronger embedding theorem…

Differential Geometry · Mathematics 2007-10-25 Liviu Ornea , Misha Verbitsky

In this paper, we study CR maps between hyperquadrics and Winkelmann hypersurfaces. Based on a previous study on the CR Ahlfors derivative of Lamel-Son and a recent result of Huang-Lu-Tang-Xiao on CR maps between hyperquadrics, we prove…

Complex Variables · Mathematics 2024-04-26 Michael Reiter , Duong Ngoc Son

Let $(X,T^{1,0}X)$ be a $(2n+1+d)$-dimensional compact CR manifold with codimension $d+1$, $d\geq1$, and let $G$ be a $d$-dimensional compact Lie group with CR action on $X$ and $T$ be a globally defined vector field on $X$ such that…

Complex Variables · Mathematics 2018-10-24 Kevin Fritsch , Hendrik Herrmann , Chin-Yu Hsiao

Let $E$ be a smooth bundle with fiber an $n$-dimensional real projective space $\mathbb{R}P^n$. We show that, if every fiber carries a positively curved pointwise strongly $1/4$-pinched Riemannian metric that varies continuously with…

Geometric Topology · Mathematics 2023-06-23 Diego Corro , Karla Garcia , Martin Günther , Jan-Bernhard Kordaß

Many complex systems involve interactions between more than two agents. Hypergraphs capture these higher-order interactions through hyperedges that may link more than two nodes. We consider the problem of embedding a hypergraph into…

Social and Information Networks · Computer Science 2023-01-06 Xue Gong , Desmond J. Higham , Konstantinos Zygalakis

In this paper, we study degenerate CR embeddings $f$ of a strictly pseudoconvex hypersurface $M\subset \bC^{n+1}$ into a sphere $\bS$ in a higher dimensional complex space $\bC^{N+1}$. The degeneracy of the mapping $f$ will be characterized…

Complex Variables · Mathematics 2012-08-16 Peter Ebenfelt

We introduce pseudoconformal structures on 4--dimensional manifolds and study their properties. Such structures are arising from two different complex operators which agree in a 2--dimensional subbundle of the tangent bundle; this subbundle…

Differential Geometry · Mathematics 2015-06-30 Ioannis D. Platis

Complex Chern-Simons bundles are line bundles with connection, originating in the study of quantization of moduli spaces of flat connections with complex gauge groups. In this paper we introduce and study these bundles in the families…

Algebraic Geometry · Mathematics 2022-03-17 Dennis Eriksson , Gerard Freixas i Montplet , Richard A. Wentworth

It is shown that any smooth closed orientable manifold of dimension $2k + 1$, $k \geq 2$, admits a smooth polynomially convex embedding into $\mathbb C^{3k}$. This improves by $1$ the previously known lower bound of $3k+1$ on the possible…

Complex Variables · Mathematics 2020-09-29 Purvi Gupta , Rasul Shafikov

For a smooth strictly pseudoconvex hypersurface in a complex manifold, we give a necessary and sufficient condition for being CR-diffeomorphic to a real-analytic CR manifold. Our condition amounts to a holomorphic extension property for the…

Complex Variables · Mathematics 2019-06-25 Ilya Kossovskiy , Dmitri Zaitsev

Datasets with non-trivial large scale topology can be hard to embed in low-dimensional Euclidean space with existing dimensionality reduction algorithms. We propose to model topologically complex datasets using vector bundles, in such a way…

Computational Geometry · Computer Science 2023-03-17 Luis Scoccola , Jose A. Perea

On a bounded strictly pseudoconvex domain in $\mathbb{C}^n$, $n >1$, the smoothness of the Cheng-Yau solution to Fefferman's complex Monge-Amp\`ere equation up to the boundary is obstructed by a local curvature invariant of the boundary,…

Complex Variables · Mathematics 2021-04-06 Sean N. Curry , Peter Ebenfelt

We construct a one-parameter family of Lorentzian conformal structures on the canonical circle bundle of a partially integrable contact almost Cauchy-Riemann manifold. This builds on previous work by Leitner, who generalised Fefferman's…

Differential Geometry · Mathematics 2025-06-11 Arman Taghavi-Chabert

We discuss the problem of embedding univalent functions into Loewner chains in higher dimension. In particular, we prove that a normalized univalent map of the ball in $\C^n$ whose image is a smooth strongly pseudoconvex domain is…

Complex Variables · Mathematics 2016-08-11 Leandro Arosio , Filippo Bracci , Erlend Fornæss Wold