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Motivated by the ideas and methods used by Naitoh in the consideration of parallel totally real submanifolds in complex space forms, the author of the present paper successfully makes use of the so called Jordan triple and (restricted)…

Differential Geometry · Mathematics 2014-08-27 Xingxiao Li

We construct complete normal forms for $5$-dimensional real hypersurfaces in $\mathbb C^3$ which are $2$-nondegenerate and also of Levi non-uniform rank zero at the origin point ${\bf p} =0$. The latter condition means that the rank of the…

Differential Geometry · Mathematics 2023-10-19 Masoud Sabzevari

Some of the 95 families of weighted K3 hypersurfaces have been known to have the isometric lattice polarizations. It is shown that weighted K3 hypersurfaces in such families are to one-to-one correspond by explicitly constructing the…

Algebraic Geometry · Mathematics 2010-09-14 Masanori Kobayashi , Makiko Mase

A number of compactifications familiar in complex-analytic geometry, in particular, the Baily-Borel compactification and its toroidal variants, as well as the Deligne-Mumford compactifications, can be covered by open subsets whose nonempty…

Algebraic Topology · Mathematics 2015-11-06 Jiaming Chen , Eduard Looijenga

We approach the study of totally real immersions of smooth manifolds into holomorphic Riemannian space forms of constant sectional curvature -1. We introduce a notion of first and second fundamental form, we prove that they satisfy a…

Differential Geometry · Mathematics 2020-02-04 Francesco Bonsante , Christian El Emam

This paper focuses on the development of harmonic and Clifford analysis techniques in the context of some conformally flat manifolds that arise from factoring out a simply-connected domain from $R^n$ by special arithmetic subgroups of the…

Differential Geometry · Mathematics 2007-05-23 R. S. Krausshar , John Ryan , Qiao Yuying

We study the moduli space $B\textrm{Diff}^+(M)$, for $M$ a reducible, oriented 3-manifold with irreducible prime factors $P_1,\ldots,P_n$. A programme of C\'esar de S\'a-Rourke, Hendriks-Laudenbach, and Hendriks-McCullough studies the…

Geometric Topology · Mathematics 2026-04-03 Rachael Boyd , Corey Bregman , Jan Steinebrunner

Let M be a compact Riemannian manifold equipped with a parallel differential form \omega. We prove a version of Kaehler identities in this setting. This is used to show that the de Rham algebra of M is weakly equivalent to its subquotient…

Differential Geometry · Mathematics 2011-03-02 Misha Verbitsky

Establishing detailed relationships between transnormal systems of different types and their behaviors under covering maps, this paper presents a classification of transnormal systems on compact 3-manifolds in the sense of equivalence. For…

Differential Geometry · Mathematics 2025-03-25 Minghao Li , Ling Yang

Hyperuniform structures are disordered, correlated systems in which density fluctuations are suppressed at large scales. Such a property generalizes the concept of order in patterns and is relevant across diverse physical systems. We…

Soft Condensed Matter · Physics 2025-09-09 Abel H. G. Milor , Otto Sumray , Heather A. Harrington , Axel Voigt , Marco Salvalaglio

Characteristic class relations in Dolbeault cohomology follow from the existence of a holomorphic geometric structure (for example, holomorphic conformal structures, holomorphic Engel distributions, holomorphic projective connections, and…

Differential Geometry · Mathematics 2025-09-29 Benjamin McKay

This note discusses some geometrically defined seminorms on the group $\Ham(M, \omega)$ of Hamiltonian diffeomorphisms of a closed symplectic manifold $(M, \omega)$, giving conditions under which they are nondegenerate and explaining their…

Symplectic Geometry · Mathematics 2007-05-23 Dusa McDuff

We consider a family $M_t^n$, with $n\ge 2$, $t>1$, of real hypersurfaces in a complex affine $n$-dimensional quadric arising in connection with the classification of homogeneous compact simply-connected real-analytic hypersurfaces in…

Complex Variables · Mathematics 2016-11-04 Alexander Isaev

The study of Sobolev and Poincar\'e inequalities for differential forms in Carnot groups and in the more general sub-Riemannian setting is still an open problem in its full generality. One may conjecture that, for general Carnot groups,…

Analysis of PDEs · Mathematics 2026-04-17 Annalisa Baldi , Alessandro Rosa

We algorithmically compute integral Eilenberg-MacLane homology of all semigroups of order at most $8$ and present some particular semigroups with notable classifying spaces, refuting conjectures of Nico. Along the way, we give an…

Algebraic Topology · Mathematics 2025-02-11 Dennis Sweeney

We study almost complex surfaces in the nearly K\"ahler $S^3\times S^3$. We show that there is a local correspondence between almost complex surfaces and solutions of the H-surface equation introduced by Wente. We find a global holomorphic…

Differential Geometry · Mathematics 2014-01-13 John Bolton , Bart Dioos , Luc Vrancken

Two sesquilinear forms $\Phi:\mathbb C^m\times\mathbb C^m\to \mathbb C$ and $\Psi:\mathbb C^n\times\mathbb C^n\to \mathbb C$ are called topologically equivalent if there exists a homeomorphism $\varphi :\mathbb C^m\to \mathbb C^n$ (i.e., a…

Representation Theory · Mathematics 2016-04-28 Carlos M. da Fonseca , Tetiana Rybalkina , Vladimir V. Sergeichuk

We study the homogeneous spaces of a simply connected, compact, simple Lie group $G$ through the lens of K-theory. Our methods apply equally well to the case where $G$ is in one of the four infinite families of classical groups, or one of…

Algebraic Topology · Mathematics 2026-05-06 John Jones , Dmitriy Rumynin , Adam R. Thomas

We use the cylindrical homomorphism and a geometric construction introduced by J. Lewis to study the Lawson homology groups of certain hypersurfaces $X\subset \mathbb{P}^{n+1}$ of degree $d\leq n+1$. As an application, we compute the…

Algebraic Geometry · Mathematics 2009-04-23 Mircea Voineagu

We study the classification of affine holomorphic bundles over a compact complex manifold $X$ in general, and we apply the general theory to the case $X=\mathbb{P}^1_\mathbb{C}$. We study the moduli space of framed, non-degenerate rank 2…

Algebraic Geometry · Mathematics 2025-01-23 Naoufal Bouchareb