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All talks will be in Skiles 006.
The conference will begin with one talk at 4:00 on Friday (preceded by a tea) and end by around 1:00 on Sunday.
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3:30-4:00 |
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Tea |
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4:00-4:50 |
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Colloquium: Peter Ozsváth |
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TBA
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5:00-6:00 |
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Lightning talk session 1 |
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9 talks see below
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6:30- |
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Social Gathering |
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Club Room at the Georgia Tech Hotel
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9:00-9:30 |
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Bagels and light refreshments |
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9:30-10:20 |
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Talk: Hyunki Min |
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Knot Floer homology, Sutured Floer homology and contact structures |
10:20-11:00 |
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Tea Break |
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11:00-11:50 |
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Talk: Neda Bagherifard |
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A 3-dimensional approach to the Andrews-Curtis Conjecture |
11:50-12:30 |
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Catered Lunch |
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Fox Bros BBQ |
12:30-1:30 |
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Lighting talk session 2 |
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8 talks see below
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1:30-2:00 |
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break |
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2:00-2:50 |
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Talk: Randy Van Why |
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TBA |
2:50-4:10 |
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Extended Tea Break |
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4:10-5:00 |
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Talk: Ina Petkova |
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Spectral GRID invariants and Lagrangian cobordisms |
6:00- |
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Banquet |
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At: South City Kitchen
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9:00-9:30 |
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Sublime Doughnuts and light refreshments |
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9:30-10:20 |
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Talk: Jonathan Zung |
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Ziggurats and taut foliations
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10:20-11:00 |
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Tea Break |
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11:00-11:50 |
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Talk: Joe Breen |
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Lagrangian sliceness and Legendrian derivatives
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| | Alexander Simons | Homology of the Legendrian Contact DGA for -1 closures of positive braids.
| | | Kevin Yeh | Train track folding automaton and the detection of T(2,3)#T(2,3) by knot Floer homology
| | | Ivan So | Equivariant knots and real monopole
| | | Nur Saglam | Contact $\tau$-Invariant for dual knots
| | | George Clare Kennedy | Investigating Aptamer Space
| | | Geoffrey Baring | scl and quasimorphisms in the free group
| | | Sriram Raghunath | Symplectic Annular Khovanov homology for symmetric knots
| | | Siavash Jafarizadeh | Functoriality for $p$-equivariant Khovanov homology
| | | Matthew Elpers | Characterizing slopes for more three manifolds
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| | Qingfeng Lyu | Persistent foliarity of some (1,1) non-L-space knots
| | | Rob McConkey | Theta, Traffic, and Connected-Sums
| | | Luke Seaton | Whitehead doubles and θ
| | | Rithwik Susheel Vidyarthi | Knot Floer Homology and the Borromean Knot
| | | Nilangshu Bhattacharyya | Stable Homotopy Type for Planar Trivalent Graphs with Perfect Matchings
| | | Fabio Capovilla-Searle | Top degree cohomology of congruence subgroups of symplectic groups
| | | Yangxiao Luo | Cornered skein lasagna theory
| | | Maxwell Throm | Symmetric knots and sl(3) homology
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Titles and Abstracts
A 3-dimensional approach to the Andrews-Curtis Conjecture The Andrews-Curtis conjecture, proposed in the 1950s, asserts that all balanced presentations of the trivial group can be simplified through specific transformations known as stable Andrews-Curtis transformations to the trivial presentation. This conjecture is connected to the smooth 4-dimensional Poincaré conjecture, and some believe that both conjectures may be incorrect. In my talk, however, I will explain a partial connection between the Andrews-Curtis equivalence and a notion of equivalence on certain families of 3-manifolds, and I will demonstrate that a version of the conjecture is not true. This is joint work with Eaman Eftekhary.
Lagrangian sliceness and Legendrian derivatives A knot is Lagrangian slice if it bounds a Lagrangian disk in the symplectic 4-ball. One may ask for such a Lagrangian disk to be decomposable, or regular, in analogy to asking for a smooth slice disk to be ribbon, or handle-ribbon. We currently do not have a characterization of Lagrangian sliceness,or an understanding of whether the additional decomposability/regularity conditions are equivalent. In this talk, I will discuss recent work on the latter, and forthcoming joint work with A. Zupan making progress toward the former.
Knot Floer homology, Sutured Floer homology and contact structures The rank of knot Floer homology contains a lot of information about a knot and its complement. Ghiggini and Ni showed that the rank of HFK in the top grading is 1 if and only if the knot is fibered. Ghiggini–Spano and Ni also showed that, for fibered knots, the rank of HFK in the second-to-top grading is equal to one more than the number of fixed points of the monodromy. There have been several attempts to estimate the rank of HFK in the second-to-top grading. Baldwin and Vela-Vick showed that the rank is greater than or equal to 1 if the knot is fibered, and Ni showed that the rank is greater than or equal to the rank in the top grading under certain additional conditions. In this talk, we give a new estimate of the rank of HFK for non-fibered knots in the second-to-top grading using sutured Floer homology and contact structures. This is joint work with Konstantinos Varvarezos.
TBA TBA
Spectral GRID invariants and Lagrangian cobordisms Knot Floer homology is a powerful invariant of knots and links, developed by Ozsvath and Szabo in the early 2000s. Among other properties, it detects the genus, detects fiberedness, and gives a lower bound to the 4-ball genus. The original definition involves counting homomorphic curves in a high-dimensional manifold, and as a result the invariant can be hard to compute. In 2007, Manolecu, Ozsvath, and Sarkar came up with a purely combinatorial description of knot Floer homology for knots in the 3-sphere, called grid homology. Soon after, Ozsvath, Szabo, and Thurston defined invariants of Legendrian knots using grid homology. We show that the filtered version of these GRID invariants, and consequently their associated invariants in a certain spectral sequence for grid homology, obstruct decomposable Lagrangian cobordisms in the symplectization of the standard contact structure, strengthening a result of Baldwin, Lidman, and Wong. This is joint work with Jubeir, Schwartz, Winkeler, and Wong.
TBA TBA
Ziggurats and taut foliations If L is a link in a 3-manifold, which Dehn surgery multislopes give rise to 3-manifolds with taut foliations? In this talk, I will discuss the ziggurat phenomenon: if one restricts to foliations transverse to a fixed flow on the link complement, the set of multislopes typically has a fractal staircase shape with rational corners. In work in progress with Thomas Massoni, we explain the ziggurat phenomenon in some contexts using tools from contact geometry.
Lightning talk
scl and quasimorphisms in the free group Stable commutator length is a stable word measure on groups which has been used to show various group theoretic results. In a paper of Danny Calegari, he proves that the scl can be computed on chains in the free group case by a rational linear programming problem which runs through certain surfaces and maximizes their Euler characteristic. On the dual side, Bavard Duality tells us that scl is equal to the supremum over homogeneous quasimorphisms. My current project with my adviser is to dualize the linear programming problem and reinterpret the variables as counting quasimorphisms to find an extremal quasimorphism for the given word.
Stable Homotopy Type for Planar Trivalent Graphs with Perfect Matchings In this talk, I will describe a space-level refinement of 2-factor homology by constructing a stable homotopy type associated to a distinguished family of planar trivalent graphs equipped with perfect matchings. The resulting spectrum is similar to the Lipshitz–Sarkar Khovanov spectrum for links and yields a stable homotopy invariant of planar trivalent graphs with perfect matchings. Moreover, we show that the closed webs obtained by performing flattenings at each crossing of an oriented link diagram—arising naturally in the context of sl3 link homology—belong to this family of planar trivalent graphs for which the spectrum is built.
Top degree cohomology of congruence subgroups of symplectic groups The cohomology of arithmetic groups has connections to many areas of mathematics such as number theory and diffeomorphism groups. Classifying spaces of congruence subgroups of symplectic groups have an algebro-geometric interpretation as the moduli space of principally polarized abelian varieties with level structures. These congruence subgroups Sp_2n(Z,L) are the kernel of the mod-L reduction map Sp_2n(Z) to Sp_2n(Z / L). By work of Borel-Serre, H^i(Sp_2n(Z / L)) vanishes for i > n^2. I will report on lower bounds in the top degree i = n^2. The key tools in the proof are the theory of Steinberg modules and highly connected simplicial complexes.
Investigating Aptamer Space Aptamers are short strands of RNA which function as chemical antibodies, binding to specific target molecules. They are engineered using a process which produces many possible candidates, but only a few of these will have actually strong binding affinity; most of the rest are false positives. As aptamers are fundamentally genetic sequences, it is an intuitive hypothesis that aptamers which are genetically "close" should also have similar binding affinity, or at least perform similarly in the candidate-generating process. We can also compare structural differences between aptamers and posit a similar line of thinking. However, using traditional clustering techniques as well as the Mapper algorithm from topological data analysis, we show that neither of these distance measures appears effective at grouping together aptamers as they relate to binding affinity.
Characterizing slopes for more three manifolds For any homotopy class h in any compact orientable 3-manifold M which is closed or has exclusively torus boundary components, we produce infinitely many pairs of distinct knots representing h with orientation-preserving homeomorphic 0-surgeries.
Functoriality for $p$-equivariant Khovanov homology I will prove that equivariant khovanov homology for $p$-periodic links is functorial for special class of equivariant cobordisms. I will mention the steps needed for the proof of functoriality in the ordinary Khovanov homology and skew them in my favor.
Cornered skein lasagna theory The Khovanov-Rozansky skein lasagna module was introduced by Morrison-Walker-Wedrich as an invariant of 4-manifold with a framed oriented link in the boundary. I will discuss an extension of the skein lasagna theory to 4-manifolds with codimension 2 corners, its behavior under gluing, and applications to trisections of 4-manifolds. This is joint work with Sarah Blackwell and Slava Krushkal.
Persistent foliarity of some (1,1) non-L-space knots We discuss an approach to finding taut foliations in (1,1) non-L-space knot complements. We use it to show that (1,1) almost L-space knots are persistently foliar.
Theta, Traffic, and Connected-Sums Bar-Natan and van der Veen recently presented their new invariant for knots, theta. It is a powerful invariant which effectively distinguishes knots that is also easily computable. We will talk about the invariant and see how the invariant is represented. Talk about how cars driving on our knots can be used to help prove things for the invariant. And how we use the cars and the resulting traffic functions to show additivity of theta under the connected sum.
Symplectic Annular Khovanov homology for symmetric knots When a knot diagram is symmetric, it induces an action on the Khovanov chain complex of the knot. We can analyze the equivariant cohomology of the chain complex with respect to this action to understand relationships between the Khovanov homology of the original knot and the Khovanov homology of the quotient knot. Seidel and Smith have defined a symplectic reformulation of combinatorial Khovanov homology, and they have used localization techniques in Floer theory to study the symplectic Khovanov homology of 2-periodic knots. In our work, we define an annular version of symplectic Khovanov homology, and apply this theory to investigate the symplectic Khovanov homology of 2-periodic and strongly invertible knots. This talk is based on joint work with Kristen Hendricks and Cheuk Yu Mak.
Contact $\tau$-Invariant for dual knots The Heegaard Floer $\tau$-invariant is a knot concordance invariant that bounds the 4–ball genus of a knot in $S^{3}$ defined by Ozsváth and Szabó using Knot Floer Homology. Later, Raoux generalized their construction to knots in a rational homology sphere and obtained lower bounds in some of these invariants. There are various computations of $\tau$-Invariant for many manifolds like this, for example, contact $\tau$-invariant defined by Hedden. Motivated by these works, we aim to compute it for dual knots. Let L be a Legendrian knot in $S^{3}$ with the standard contact structure and $(Y, \xi)$ be the manifold obtained by Legendrian surgery on L. Our goal is to calculate the $\tau$-invariant $\tau_{\xi}(S^3_{tb-1}(K),K_{tb-1})$ of the dual knot K in terms of the smooth $\tau$-invariant $\tau(K)$ in $S^{3}$ and the surgery info. This is joint work with Katherine Raoux.
Whitehead doubles and θ We introduce a computational tool to generate t-twisted, s-clasped Whitehead doubles of knots. Using this tool, we propose a conjecture describing the behavior of θ on untwisted Whitehead doubles and verify the conjecture for all prime knots with fewer than 13 crossings. Our results provide supporting evidence for a broader conjecture that θ, introduced by Bar-Natan and van der Veen, may be equal to the two-loop polynomial, a previously studied knot invariant.
Homology of the Legendrian Contact DGA for -1 closures of positive braids. Given a Legendrian knot, Chekanov introduced a way to associate a differential graded algebra (DGA) to the knot. The homology of this DGA is an invariant that has been used to differentiate Legendrian knots that cannot be distinguished with tb and rotation numbers. In this brief talk, I will explain how to study the homology of these DGAs using noncommutative Groebner bases.
Equivariant knots and real monopole Equivariant knots are knots with a specified symmetry. Extending from the definition of equivariant knots, there are the notions of equivariant Seifert surface and equivariant slice surface in D^4. However, even for the equivariant Seifert genus, it is hard to determine as there is no analogue of Seifert algorithm for equivariant knots. In this talk, I will talk about a work in progress which utilize invariants from real monopole Floer homotopy type to give a lower bound for equivariant slice genus. This is a joint work with Jin Miyazawa.
Symmetric knots and sl(3) homology An equivariant link is a link that has a finite order group action preserving the link. From this group action, one can define a compatible group action on the Khovanov homology of the knot. This gives rank inequalities on the odd and even Khovanov homologies for the knot as in Stoffregen-Zhang. We hope to extend this to sl(3) link homology.
Knot Floer Homology and the Borromean Knot Mapping class groups of surfaces are interesting objects to study. One way to study them is to form the mapping torus, which is a three-manifold. For surfaces with a single boundary, this naturally gives rise to a 3-manifold along with a knot inside it, and we can assign it the Knot Floer complex. A natural question to ask is when is this injective? When the monodromy is the Identity, it is in fact injective, and this corresponds to the Borromean knot. We will try to answer this question when the monodromy is a boundary Dehn twist.
Train track folding automaton and the detection of T(2,3)#T(2,3) by knot Floer homology We aim to show that there are no hyperbolic knots with the same HFK as that of T(2,3)#T(2,3). This amounts to classifying all pseudo-Anosov maps on the disk with six marked points that lift to fixed-point free pseudo Anosov maps. To that end, we give a description of an algorithm that generates all such possible train tracks on the disk that can carry such maps. From these we can perform an extensive case analysis to enumerate all possible maps on the disk carried by these train tracks. We then rule out all of the cases using some calculations on the Alexander polynomial, or calculations on the homology in the lift.
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