English
Related papers

Related papers: ECH embedding obstructions for rational surfaces

200 papers

Let $M$ be a projective toric manifold. We prove two results concerning respectively Kaehler-Einstein submanifolds of M and symplectic embeddings of the standard euclidean ball in M. Both results use the well-known fact that M contains an…

Differential Geometry · Mathematics 2014-10-15 Claudio Arezzo , Andrea Loi , Fabio Zuddas

We call a symplectic rational surface $(X,\omega)$ \textit{positive} if $c_1(X)\cdot[\omega]>0$. The positivity condition of a rational surface is equivalent to the existence of a divisor $D\subset X$, such that $(X, D)$ is a log Calabi-Yau…

Symplectic Geometry · Mathematics 2022-12-06 Jun Li , Tian-Jun Li , Weiwei Wu

We obtain a dynamical--topological obstruction for the existence of isometric embedding of a Riemannian manifold-with-boundary $(M,g)$: if the first real homology of $M$ is nontrivial, if the centre of the fundamental group is trivial, and…

Differential Geometry · Mathematics 2023-09-14 Siran Li

A complete embedding is a symplectic embedding $\iota:Y\to M$ of a geometrically bounded symplectic manifold $Y$ into another geometrically bounded symplectic manifold $M$ of the same dimension. When $Y$ satisfies an additional finiteness…

Symplectic Geometry · Mathematics 2023-01-25 Yoel Groman , Umut Varolgunes

Let $M$ be a smooth projective variety and $\mathbf{D}$ an ample normal crossings divisor. From topological data associated to the pair $(M, \mathbf{D})$, we construct, under assumptions on Gromov-Witten invariants, a series of…

Symplectic Geometry · Mathematics 2021-02-24 Sheel Ganatra , Daniel Pomerleano

This note constructs sharp obstructions for stabilized symplectic embeddings of an ellipsoid into a ball, in the case when the initial four-dimensional ellipsoid has `eccentricity' of the form 3n-1 for some integer n.

Symplectic Geometry · Mathematics 2018-11-28 Dusa McDuff

We prove two assumptions made in an article by Ya.A. Butko, M. Grothaus, O.G. Smolyanov concerning the existence of a strongly continuous operator semigroup solving a Cauchy-Dirichlet problem for an elliptic differential operator in a…

Functional Analysis · Mathematics 2011-12-09 Benedict Baur , Florian Conrad , Martin Grothaus

In this paper, we construct singular Lagrangian fibrations on some examples of disk cotangent bundles in dimensions 4 and 6. As an application, we show how this construction can be used to obtain toric domains in some cases. In particular,…

Symplectic Geometry · Mathematics 2025-06-03 Santiago Achig-Andrango , Renato Vianna , Alejandro Vicente

Let $\varphi:F_1\to F_2$ be an injective morphism of free groups. If $\varphi$ is geometric (i.e. induced by an inclusion of oriented compact connected surfaces with nonempty boundary), then we show that $\varphi$ is an isometric embedding…

Geometric Topology · Mathematics 2025-01-28 Alexis Marchand

Several types of generically-nondegenerate Poisson structures can be effectively studied as symplectic structures on naturally associated Lie algebroids. Relevant examples of this phenomenon include log-, elliptic, $b^k$-, scattering and…

Symplectic Geometry · Mathematics 2020-11-30 Ralph L. Klaasse

We define a family of symplectic invariants which obstruct exact symplectic embeddings between Liouville manifolds, using the general formalism of linearized contact homology and its L-infinity structure. As our primary application, we…

Symplectic Geometry · Mathematics 2024-04-24 Sheel Ganatra , Kyler Siegel

We describe the equivariant cohomology ring of rationally smooth projective embeddings of reductive groups. These embeddings are the projectivizations of reductive monoids. Our main result describes their equivariant cohomology in terms of…

Algebraic Geometry · Mathematics 2015-07-21 Richard Gonzales

This paper continues the investigation of the relation between the geometry of a circle embedding and the values of its Fourier coefficients. First, we answer a question of Kovalev and Yang concerning the support of the Fourier transform of…

Complex Variables · Mathematics 2020-04-02 Liulan Li , Leonid V. Kovalev

The Hamiltonian shape invariant of a domain $X \subset \mathbb R^4$, as a subset of $\mathbb R^2$, describes the product Lagrangian tori which may be embedded in $X$. We provide necessary and sufficient conditions to determine whether or…

Symplectic Geometry · Mathematics 2021-05-11 Richard Hind , Jun Zhang

Firstly we show a generalization of the (1,1)-Lefschetz theorem for projective toric orbifolds and secondly we prove that on 2k-dimensional quasi-smooth hypersurfaces coming from quasi-smooth intersection surfaces, under the Cayley trick,…

Algebraic Geometry · Mathematics 2023-02-09 William D. Montoya

We extend the family of capacities given by McDuff and Siegel by including a constraint $\ell$ on the number of positive asymptotically cylindrical ends of curves showing up in the definition. We prove a generalized computation formula for…

Symplectic Geometry · Mathematics 2025-08-19 Jonathan Michala

We construct a uniformly bounded symplectic structure on $S^2 \times \mathbb{R}^4$ admitting embeddings by arbitrarily large balls. This provides a counterexample to a recent conjecture of Savelyev. We then prove the conjecture holds for a…

Symplectic Geometry · Mathematics 2025-07-16 Spencer Cattalani

We investigate the possibility of embedding minimal abelian surfaces in smooth toric 4-folds with Picard number 2. The existence of such an embedding imposes conditions on the 4-fold, which we partly describe. On the other hand, we exhibit…

Algebraic Geometry · Mathematics 2007-05-23 G. K. Sankaran

Let (M,\omega) be a symplectic manifold, and (\Sigma,\sigma) a closed connected symplectic 2-manifold. We construct a weakly symplectic form {\omega^{D}}_{(\Sigma, \sigma)} on the space of immersions \Sigma \to M that is a special case of…

Symplectic Geometry · Mathematics 2011-08-03 Liat Kessler

A class of graphs that lies strictly between the classes of graphs of genus (at most) $k-1$ and $k$ is studied. For a fixed orientable surface $S_k$ of genus $k$, let $A_{xy}^k$ be the minor-closed class of graphs with terminals $x$ and $y$…

Combinatorics · Mathematics 2011-12-06 Bojan Mohar , Petr Škoda