arXiv research

Study equivariant isotopy in higher dimensions, finding exceptions.

New invariants refine link homology, showing large genus differences.

The paper proves the regularity of cohomogeneity two problems and constructs minimal hypersurfaces on spheres.

The purpose of this paper is to construct and study equivariant Khovanov homology - a version of Khovanov homology theory for periodic links. Since our construction works regardless of the characteristic of the coefficient ring it generalizes a previous construction by Chbili. We establish invariance under equivariant …

New example of non-smooth isotopy after stabilization in 4-manifolds.

Let $Δ$ be a trivial knot in the three-sphere. For every finite cyclic group $G$ of odd order, we construct a $G$-equivariant Khovanov homology with coefficients in the filed $\F_{2}$. This homology is an invariant of links up to isotopy in $(S^{3},Δ)$. Another interpretation is given using the categorification of the …

New minimal hypersphere found in 4-sphere solving Bernstein problem.

The paper proves $n$-transitivity for equivariant diffeomorphisms of manifolds.

If a continuous map f: X->Q is approximable arbitrary closely by embeddings X->Q, can some embedding be taken onto f by a pseudo-isotopy? This question, called Isotopic Realization Problem, was raised by Shchepin and Akhmet'ev. We consider the case where X is a compact n-polyhedron, Q a PL m-manifold and show that the …

A real 3-manifold is a smooth 3-manifold together with an orientation preserving smooth involution, called a real structure. In this article we study open book decompositions on smooth real 3-manifolds that are compatible with the real structure. We call them real open book decompositions. We show that each real open b…

The paper creates non-isotopic but homotopic diffeomorphisms in 4-manifolds.

The $\mathbb{Z}_{2}$-equivariant Heegaard Floer cohomlogy $\widehat{HF}_{\mathbb{Z}_{2}}(Σ(K))$ of a knot $K$ in $S^{3}$, constructed by Hendricks, Lipshitz, and Sarkar, is an isotopy invariant which is defined using bridge diagrams of $K$ drawn on a sphere. We prove that $\widehat{HF}_{\mathbb{Z}_{2}}(Σ(K))$ can be co…

Classifies real tight contact structures on lens spaces and solid tori.

Study surfaces in 4-manifolds with cyclic fundamental group.

New invariant shows Dehn twist on connected sum of homology tori is not isotopic to identity.

We describe a generalization of GKM theory for actions of arbitrary compact connected Lie groups. To an action satisfying the non-abelian GKM conditions we attach a graph encoding the structure of the non-abelian 1-skeleton, i.e., the subspace of points with isotopy rank at most one less than the rank of the acting gro…

We prove a theorem on equivariant maps implying the following two corollaries: (1) Let N and M be compact orientable n-manifolds with boundaries such that M\subset N, the inclusion M\to N induces an isomorphism in integral cohomology, both M and N have (n-d-1)-dimensional spines and m > max {n+2, (3n+1-d)/2} . Then the…

Study of disks in complex projective space with specific fundamental groups.

We construct an isotopy of a planar compactum that is not the restriction of an isotopy of any planar continuum.

A braid-like isotopy for links in 3-space is an isotopy which uses only those Reidemeister moves which occur in isotopies of braids. We define a refined Jones polynomial and its corresponding Khovanov homology which are, in general, only invariant under braid-like isotopies.

New obstructions show some 4-manifold homeomorphisms are pseudo-isotopic but not isotopic.

Approaches 4D Schoenflies via pseudo-isotopy.

For each braid $β\in Br_n$ we construct a $2$-periodic complex $\mathbb{S}_β$ of quasi-coherent $\mathbb{C}^*\times \mathbb{C}^*$-equivariant sheaves on the non-commutative nested Hilbert scheme $Hilb_{1,n}^{free}$. We show that the triply graded vector space of the hypecohomology $ \mathbb{H}( \mathbb{S}_β\otimes \wed…

Classifies curves up to symplectic isotopy.

In this paper we solve the following problem in the affirmative: Let $Z$ be a continuum in the plane $\complex$ and suppose that $h:Z\times [0,1]\to\complex$ is an isotopy starting at the identity. Can $h$ be extended to an isotopy of the plane? We will provide a new characterization of an accessible point in a planar …

Smooth isotopy on cube saves energy with extra dimensions.

A star-like isotopy for oriented links in 3-space is an isotopy which uses only Reidemeister II moves with opposite orientations and Reidemeister III moves with alternating orientations when checking the strands clockwise (or anticlockwise). We define a link polynomial derived from the Jones polynomial which is, in gen…

Refined 1-cocycle for knots helps quantify isotopies.

Classifies isotopy classes of links from Thompson's group F and its subgroup.

Uniform convergence of isotopies implies ambient isotopy, aiding knot equivalence.

Proves a Thom Isotopy Theorem for nonproper semialgebraic maps.

Minimal surfaces and curves can have singularities removed by isotopy.

Improved proofs for topological and smooth pseudo-isotopies of simply connected 4-manifolds.

The study constructs examples of pseudo-isotopic but not isotopic 4-manifold diffeomorphisms.

In this paper we define and study flexible links and flexible isotopy in projective space. Flexible links are meant to capture the topological properties of real algebraic links. We classify all flexible links up to flexible isotopy using Ekholms interpretation of Viros encomplexed writhe.

Veering triangulations link Thurston norm and isotopy of surfaces.

Proof confirms Hamiltonian isotopy of submanifolds.

We construct counterexamples to lifting properties of Hamiltonian and contact isotopies.

This paper introduces two virtual knot theory ``analogues'' of a well-known family of invariants for knots in thickened surfaces: the Grishanov-Vassiliev finite-type invariants of order two. The first, called the three loop isotopy invariant, is an invariant of virtual knots while the second, called the three loop fram…

The symplectic isotopy conjecture states that every smooth symplectic surface in $CP^2$ is symplectically isotopic to a complex algebraic curve. Progress began with Gromov's pseudoholomorphic curves [Gro85], and progressed further culminating in Siebert and Tian's proof of the conjecture up to degree 17 [ST05], but fur…

Proof of isotopy invariance in Khovanov link homology.

Classifies smooth isotopy of a specific Lagrangian embedding.

We define an equivalence relation called A-isotopy between finitely determined map-germs, which is a strengthened version of A-equivalence. We consider the number of A-isotopy classes of equidimensional Morin singularities, and some other well-known low-dimensional singularities. We also give an application to stable p…

Study isotopy and concordance for metrics on manifolds with boundary.

This paper investigates dynamics that persist under isotopy in classes of orientation-preserving homeomorphisms of orientable surfaces. The persistence of periodic points with respect to periodic and strong Nielsen equivalence is studied. The existence of a dynamically minimal representative with respect to these relat…

We establish the uniqueness up to Hamiltonian isotopy of the Lagrangian spheres in some four dimensional Stein manifolds.

Constructs pseudo-isotopies with Cerf diagrams and Hatcher-Wagoner invariants for barbell maps.

We present a grid diagram analogue of Carter, Rieger and Saito's smooth movie theorem. Specifically, we give definitions for grid movies, grid movie isotopies and present a definition of grid planar isotopy as a particular subset of the grid diagram moves: stabilization, destabilization and commutation. We show that gr…