arXiv research

Acyclicity proven for curve complex on surfaces.

By the work of Harer, the reduced homology of the complex of curves is a fundamental cohomological object associated to all torsion free finite index subgroups of the mapping class group. We call this homology group the Steinberg module of the mapping class group. It was previously known that the curve complex has the …

New Jordan Floer homology shows every curve inscribes every isosceles trapezoid.

Persistent homology can recognize knotting in curves.

Floer homology applied to inscribing rectangles into curves.

Develops persistent Khovanov homology for tangles.

In joint work with J. Rasmussen, we gave an interpretation of Heegaard Floer homology for manifolds with torus boundary in terms of immersed curves in a punctured torus. In particular, knot Floer homology is captured by this invariant. Appealing to earlier work of the authors on bordered Floer homology, we give a formu…

We use tropical curves and toric degeneration techniques to construct closed embedded Lagrangian rational homology spheres in a lot of Calabi-Yau threefolds. We apply this construction to the tropical curves obtained from the 2875 lines on the quintic Calabi-Yau threefold. Each admissible tropical curve gives a Lagrang…

The abstract conjectures a link between knot homologies and quiver partition functions.

Characterizes unknotted curves on Seifert surfaces of twist knots.

This note is devoted to a trick which yields almost trivial proofs that certain complexes associated to topological surfaces are connected or simply connected. Applications include new proofs that the complexes of curves, separating curves, nonseparating curves, pants, and cut systems are all connected for genus $g \gg…

Besides offering a friendly introduction to knot homologies and quantum curves, the goal of these lectures is to review some of the concrete predictions that follow from the physical interpretation of knot homologies. In particular, this interpretation allows one to pose questions that would not have been asked otherwi…

Geometric interpretation of tangle invariants using immersed curves.

Study on quadratic L-functions using hyperelliptic curves and homology.

New algebraic method for knot Floer homology computation.

We show that if $V^3$ is a handlebody in $\R^3$, with curves $J_1, ..., J_g \subset \partial V$ which are the attaching curves for a Heegaard splitting of a homology sphere, then there exists a homeomorphism $h\colon V \to V$ so that each of the curves $h(J_i)$ bounds an orientable surface in $\R^3 - int(V)$. This lead…

A new method converts knot Floer homology to immersed curves.

Solves index problem for curved BGG sequences in parabolic geometry.

In previous work with Schoenfeld, we considered a string-type chain complex of curves on surfaces, with differential given by resolving crossings, and computed the homology of this complex for discs. In this paper we consider the corresponding "string homology" of annuli. We find this homology has a rich algebraic stru…

Knot Floer homology is reinterpreted as immersed curves.

We show that the sutured Floer homology of a sutured 3-manifold of the form $(D^2 \times S^1, F \times S^1)$ can be expressed as the homology of a string-type complex, generated by certain sets of curves on $(D^2, F)$ and with a differential given by resolving crossings. We also give some generalisations of this isomor…

New homomorphism proven using immersed curves on disks.

We apply the methods of Heegaard Floer homology to identify topological properties of complex curves in the complex projective plane. As one application, we resolve an open conjecture that constrains the Alexander polynomial of the link of the singular point of the curve in the case that there is exactly one singular p…

The paper tackles deeply slice knots via immersed curves.

New method finds unbranched covers with non-kernel homology.

This paper gives a geometric interpretation of bordered Heegaard Floer homology for manifolds with torus boundary. If $M$ is such a manifold, we show that the type D structure $\widehat{\mathit{CFD}}$ may be viewed as a set of immersed curves decorated with local systems in $\partial M$. These curves-with-decoration ar…

Survey of contact homology for contact manifolds.

Algorithm converts curves on ribbon surfaces to contact surgery diagrams.

Proves conjecture about surface cover homology.

We study here some aspects of the topology of the space of smooth, stable, genus 0 curves in a Riemannian manifold $X$, i.e. the Kontsevich stable curves, which are not necessarily holomorphic. We use the Hofer-Wysocki-Zehnder polyfold structure on this space and some natural characteristic classes, to show that for $X…

Study corrects previous work on knot Floer homology of certain pretzel knots.

Study algebraic curves in C^2 using Floer theory.

We study natural additional structures on real algebraic surfaces with trivial first homology mod 2 of the complexification. If the set of real points realizes the zero of the second homology mod 2 of the complexification, then the set of real points is equipped with a pair of opposite orientations and a Spin structure…

New knots not slice in rational 4-balls found.

We construct an algebraic version of Lagrangian Floer homology for immersed curves inside the pillowcase. We first associate to the pillowcase an algebra A. Then to an immersed curve L inside the pillowcase we associate an A infinity module M(L) over A. Then we prove that Lagrangian Floer homology HF(L,L') is isomorphi…

This is the second of five papers that construct an isomorphism between the Seiberg-Witten Floer homology and the Heegaard Floer homology of a given compact, oriented 3-manifold. The isomorphism is given as a composition of three isomorphisms; the first of these relates a version of embedded contact homology on an an a…

Conditions for simple closed curves in surface covers.

We apply contact homology to obtain new results in the problem of distinguishing immersed plane curves without dangerous self-tangencies.

Rickard complexes in the context of categorified quantum groups can be used to construct braid group actions. We define and study certain natural deformations of these complexes which we call curved Rickard complexes. One application is to obtain deformations of link homologies which generalize those of Batson-Seed arX…

Square inscribed in a curve made of two graph functions.

Satellite knots with (1,1)-patterns have their Floer homology computed using immersed curves.

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.

Study $d$-invariants of L-space double branched covers of arborescent links.

Aramayona and Leininger have provided a "finite rigid subset" $\mathfrak{X}(Σ)$ of the curve complex $\mathscr{C}(Σ)$ of a surface $Σ= Σ^n_g$, characterized by the fact that any simplicial injection $\mathfrak{X}(Σ) \to \mathscr{C}(Σ)$ is induced by a unique element of the mapping class group $\mathrm{Mod}(Σ)$. In this…

Let Y be a closed oriented 3-manifold with a contact form such that all Reeb orbits are nondegenerate. The embedded contact homology (ECH) index associates an integer to each relative 2-dimensional homology class of surfaces whose boundary is the difference between two unions of Reeb orbits. This integer determines the…

Linear bound on Betti numbers of negatively curved orbifolds.

Lower bounds on unknotting number for cabled knots.

The reduced Burau representation $V_n$ of the braid group $B_n$ is obtained from the action of $B_n$ on the homology of an infinite cyclic cover of the disc with $n$ punctures. The group homology $H_*(B_n;V_n)$ of braid groups with coefficients in the complexified reduced Burau representation is calculated. Our topolog…