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Related papers: From flops to diffeomorphism groups

200 papers

$p$-Adic compactifications of geometric loop and diffeomorphism groups of compact manifolds on finite-dimensional spaces over non-Archimedean fields are investigated. Weakened topology is introduced. The structure of newly constructed…

Group Theory · Mathematics 2007-05-23 S. Ludkovsky , B. Diarra

We construct a symplectic structure on a disc that admits a compactly supported symplectomorphism which is not smoothly isotopic to the identity. The symplectic structure has an overtwisted concave end; the construction of the…

Symplectic Geometry · Mathematics 2017-03-17 Roger Casals , Ailsa Keating , Ivan Smith

We prove uniqueness, up to diffeomorphism, of symplectically aspherical fillings of certain unit cotangent bundles, including those of higher-dimensional tori.

Symplectic Geometry · Mathematics 2023-10-05 Hansjörg Geiges , Myeonggi Kwon , Kai Zehmisch

The notion of a holomorphically symplectic manifold can be generalized to the singular one. This paper studies the birational contraction maps between symplectic varieties, and then describes the deformation of a symplectic variety which…

Algebraic Geometry · Mathematics 2007-05-23 Yoshinori Namikawa

We characterise boundary shaped disc like neighbourhoods of certain isotropic submanifolds in terms of aperiodicity of Reeb flows. We prove uniqueness of homotopy and diffeomorphism type of such contact manifolds assuming non-existence of…

Symplectic Geometry · Mathematics 2022-08-30 Myeonggi Kwon , Kevin Wiegand , Kai Zehmisch

Banyaga has shown that the group of symplectomorphisms Symp(N) of a compact symplectic manifold (N,w) determines the symplectic structure. This motivates the study of the homotopy properties of Symp(N). Gromov has shown that the group of…

Differential Geometry · Mathematics 2007-05-23 Aristide Tsemo

We study the relation between the symplectomorphism group Symp M of a closed connected symplectic manifold M and the symplectomorphism and diffeomorphism groups Symp \TM and Diff \TM of its one point blow up \TM. There are three main…

Symplectic Geometry · Mathematics 2007-07-30 Dusa McDuff

Let M be a smooth connected compact surface, P be either the real line R^1 or the circle S^1, and f:M-->P be a smooth mapping. In a previous series of papers for the case when f is a Morse map the author calculated the homotopy types of…

Geometric Topology · Mathematics 2009-12-17 Sergiy Maksymenko

We provide examples of contact manifolds of any odd dimension $\geq 5$ which are not diffeomorphic but have exact symplectomorphic symplectizations.

Symplectic Geometry · Mathematics 2015-12-11 Sylvain Courte

We associate each endomorphism of a finite cyclic group with a digraph and study many properties of this digraph, including its adjacent matrix and automorphism group.

Combinatorics · Mathematics 2011-08-16 Min Sha

If G is a (connected) complex Lie Group and Z is a generalized flag manifold for G, the the open orbits D of a (connected) real form G_0 of G form an interesting class of complex homogeneous spaces, which play an important role in the…

Representation Theory · Mathematics 2008-02-03 Edward G. Dunne , Roger Zierau

The paper provides a link between ergodic theory and symplectic topology. A classical notion of ergodic theory is a skew product map associated with a loop in a group of transformations. We study skew products which come from loops in the…

Differential Geometry · Mathematics 2007-05-23 Leonid Polterovich

In this survey article, we summarize some recent progress and problems on the symplectomorphism groups, with an emphasis on the connection to the space of ball-packings.

Symplectic Geometry · Mathematics 2019-10-08 Jun Li , Weiwei Wu

We prove a result that relates the number of homomorphisms from the fundamental group of a compact nonorientable surface to a finite group $G$, where conjugacy classes of the boundary components of the surface must map to prescribed…

Group Theory · Mathematics 2025-02-19 Michael R. Klug

We prove that if two closed, connected, regular cosymplectic manifolds have isomorphic groups of cosymplectomorphisms (as topological groups), then the underlying manifolds are diffeomorphic. The proof proceeds by characterizing the Reeb…

Symplectic Geometry · Mathematics 2026-02-09 Etienne Djoukeng , Stephane Tchuiaga

We discuss some examples of open manifolds which admit non-isomorphic symplectic structures of Liouville type.

Symplectic Geometry · Mathematics 2010-12-14 Paul Seidel

The paper is devoted to the study of homotopy properties of stabilizers of smooth functions on oriented surfaces, i.e., groups of diffeomorphisms of surfaces preserving a given function. For some class of smooth functions which is a…

Geometric Topology · Mathematics 2026-05-06 Bohdan Feshchenko

We consider groups of orientation-preserving real analytic diffeomorphisms of the circle which have a finite image under the rotation number function. We show that if such a group is nondiscrete with respect to the $C^1$-topology then it…

Dynamical Systems · Mathematics 2008-11-04 Yoshifumi Matsuda

For r at least 3, p at least 2, we classify all actions of the groups Diff^r_c(R) and Diff^r_+(S1) by C^p -diffeomorphisms on the line and on the circle. This is the same as describing all nontrivial group homomorphisms between groups of…

Geometric Topology · Mathematics 2013-09-10 Kathryn Mann

For each nonnegative integer m we show that any closed, oriented topological four-manifold with fundamental group Z_{4m+2} and odd intersection form, with possibly seven exceptions, either admits no smooth structure or admits infinitely…

Geometric Topology · Mathematics 2024-06-14 R. Inanc Baykur , Andras I. Stipsicz , Zoltan Szabo