arXiv research

Defines cobordism maps connecting Khovanov and instanton homologies.

Study shows Khovanov homology's relation to decomposable Lagrangian cobordisms.

Study on knot concordance and homology cobordism using Heegaard Floer homology.

3-manifolds with specific homology are cobordant if homeomorphic.

Paper extends cobordism maps in Khovanov and instanton homologies.

New example shows figure eight knot not smoothly concordant but homology cobordant.

Study Brieskorn spheres using Floer homology, generating infinite rank summands in homology cobordism.

It has been a central open problem in Heegaard Floer theory whether cobordisms of links induce homomorphisms on the associated link Floer homology groups. We provide an affirmative answer by introducing a natural notion of cobordism between sutured manifolds, and showing that such a cobordism induces a map on sutured F…

We study the problem of defining maps on link Floer homology induced by unoriented link cobordisms. We provide a natural notion of link cobordism, disoriented link cobordism, which tracks the motion of index zero and index three critical points. Then we construct a map on unoriented link Floer homology associated to a …

New cobordism maps for instanton knot homology help compute surgeries on knots.

The paper studies hyperbolic three-manifolds and their geometric constraints.

Rational homology ribbon cobordism defines a partial order on 3-manifolds.

We compute the $\mathrm{Pin}(2)$-equivariant Seiberg-Witten Floer homology of Seifert rational homology three-spheres in terms of their Heegaard Floer homology. As a result of this computation, we prove Manolescu's conjecture that $β=-\barμ$ for Seifert integral homology three-spheres. We show that the Manolescu invari…

Study non-orientable link cobordisms using Floer homologies to prove inequalities.

We consider the question of when a rational homology 3-sphere is rational homology cobordant to a connected sum of lens spaces. We prove that every rational homology cobordism class in the subgroup generated by lens spaces is represented by a unique connected sum of lens spaces whose first homology embeds in any other …

Study ribbon homology concordances using link Floer homology.

It is known that every closed oriented 3-manifold is homology cobordant to a hyperbolic 3-manifold. By contrast we show that many homology cobordism classes contain no Seifert fibered 3-manifold. This is accomplished by determining the isomorphism type of the rational cohomology ring of all Seifert fibered 3-manifolds …

New techniques in Khovanov homology help distinguish exotic surfaces in 4-ball.

Let S be a compact oriented surface. A homology cobordism of S is a cobordism C between two copies of S, such that both the "top" inclusion and the "bottom" inclusion of S in C induce isomorphisms in homology. Homology cobordisms of S form a monoid, into which the mapping class group of S embeds by the mapping cylinder…

Periodic Floer homology (PFH) is a Gromov-Floer type invariant for fibered three-manifolds with Hamiltonian structures. The cobordism maps on periodic Floer homology induced by symplectic cobordisms are currently only defined indirectly by using Seiberg-Witten theory. In this paper, we investigate the cobordism maps in…

Study shows quotient group is infinitely generated.

A homology cylinder over a compact manifold is a homology cobordism between two copies of the manifold together with a boundary parametrization. We study abelian quotients of the homology cobordism group of homology cylinders. For homology cylinders over general surfaces, it was shown by Cha, Friedl and Kim that their …

Trisections help compute Heegaard Floer homology invariants.

We construct cobordism maps on link Floer homology associated to decorated link cobordisms. The maps are defined on a curved chain homotopy type invariant. We describe the construction, and prove invariance. We also make a comparison with the graph TQFT for Heegaard Floer homology.

For any $s \in [-\infty, 0]$ and oriented homology 3-sphere $Y$, we introduce a homology cobordism invariant $r_s(Y)\in (0,\infty]$. The values $\{r_s(Y)\}$ are included in the critical values of the $SU(2)$-Chern-Simons functional of $Y$, and we show a negative definite cobordism inequality and a connected sum formul…

The paper introduces a cobordism for Khovanov homology crossing change and categorifies Vassiliev skein relations.

This paper explores how many positive integer surgeries on a knot produce a manifold rational homology cobordant to a lens space.

We study 4-dimensional homology cobordisms without 3-handles, showing that they interact nicely with Thurston geometries, character varieties, and instanton and Heegaard Floer homologies. Using these, we derive obstructions to such cobordisms. As one example of these obstructions, we generalize other recent results on …

Study uses twisted Alexander polynomials to link fibered classes in 3-manifolds.

Two codimension-one submanifolds are cobordant if they have the same homology class.

Lagrangian cobordisms are three-dimensional compact oriented cobordisms between once-punctured surfaces, subject to some homological conditions. We extend the Le-Murakami-Ohtsuki invariant of homology three-spheres to a functor from the category of Lagrangian cobordisms to a certain category of Jacobi diagrams. We prov…

Survey of homology cobordism group with open problems.

Python tool calculates cobordism maps in Khovanov homology.

This paper continues our exploration of homology cobordism of 3-manifolds using our recent results on Cheeger-Gromov rho-invariants associated to amenable representations. We introduce a new type of torsion in 3-manifold groups we call hidden torsion, and an algebraic approximation we call local hidden torsion. We cons…

Extends Khovanov bracket to link cobordisms, proving functoriality up to scalars.

In this paper, we introduce a category of graded commutative rings with certain algebraic morphisms, to investigate the cobordism category of plumbed 3-manifolds. In particular, we define a non-associative distributive algebra that gives necessary conditions for an abstract morphism between the homologies of two plumbe…

The homology cobordism group of homology cylinders is a generalization of the mapping class group and the string link concordance group. We study this group and its filtrations by subgroups by developing new homomorphisms. First, we define extended Milnor invariants by combining the ideas of Milnor's link invariants an…

The study connects knot Floer homology and Lagrangian cobordisms.

We construct maps on hat Heegaard Floer homology for cobordisms decorated with graphs. The graph TQFT allows for cobordisms with disconnected ends. Our construction uses Juhász's sutured Floer TQFT. We compute the maps for several elementary graph cobordisms. As an application, we compute the action of the fundamental …

In this paper we present our results on the homology cobordism group $\Th$ of the oriented integral homology 3-spheres. We specially emphasize the role played in the subject by the gauge theory including Floer homology and invariants by Donaldson and Seiberg -- Witten.

In this paper we construct gluing maps and cobordism maps for sutured monopole Floer homology.

New homology $q_2$ from 3D cobordism to integers.

Heegaard Floer homology study confirms composition maps match up to homotopy.

Determines conditions for ribbon cobordisms between lens spaces.

The paper extends a knot invariant to graphs and connects it to homology cylinders.

Proves complex homology three-spheres can be bounded by many handles.

Study shows torsion order bounds band-unlinking number for knot cobordisms.

We establish a structural understanding of the involutive Heegaard Floer homology for all linear combinations of almost-rational (AR) plumbed three-manifolds. We use this to show that the Neumann-Siebenmann invariant is a homology cobordism invariant for all linear combinations of AR plumbed homology spheres. As a coro…