The 19th East Asian Conference onGeometric Topology

February 19–22, 2024
RIMS, Kyoto University, Japan
https://www.kurims.kyoto-u.ac.jp/~eacgt/

The 19th East Asian Conference onGeometric Topology
February 19–22, 2024
RIMS, Kyoto University, Japan

Program Committee :Hyungryul Baik (KAIST), Jae Choon Cha (POSTECH),
Seiichi Kamada (Osaka University), Sang-hyun Kim (KIAS),
Toshitake Kohno (Meiji University), Yi Liu (Peking University),
Tomotada Ohtsuki (RIMS, Kyoto University),
Ruifeng Qiu (East China Normal University), Jiajun Wang (Peking University),
Ying Zhang (Soochow University)

Founding Members :Boju Jiang (Peking University), Gyo Taek Jin (KAIST),
Mitsuyoshi Kato (Kyushu University),
Akio Kawauchi (Osaka Metropolitan University),
Ki Hyoung Ko (KAIST), Yukio Matsumoto (Gakushuin University),
Shicheng Wang (Peking University)

Organizing Committee :Tetsuya Abe, Ayumu Inoue, Katsumi Ishikawa, Tetsuya Ito,
Tomotada Ohtsuki (chair), Tadayuki Watanabe, Wataru YuasaiWelcome to
The 19th East Asian Conference on Geometric Topology
February 19–22, 2024
RIMS, Kyoto University, Japan
https://www.kurims.kyoto-u.ac.jp/~eacgt/
Welcome to RIMS, Kyoto University, Japan. The purpose of the conference is to help
promoting the academic exchange and the friendship among researchers of three East
Asian countries in the area of geometric topology and encouraging graduate studentsof the three countries to study in this fascinating area of mathematics.
This conference is supported by the following:
Research Institute for Mathematical Sciences, Kyoto University
JSPS, Grant-in-Aid for Scientific Research (A): JP21H04428
JSPS, Grant-in-Aid for Scientific Research (A): JP19K21830
JSPS, Grant-in-Aid for Scientific Research (C): JP23K03110
JSPS, Grant-in-Aid for Exploratory Research: JP19K21830
We hope you will enjoy the conference.

Tomotada Ohtsuki
Chair

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Contents
1.
2.
3.
4.
5.

Information
Talk Schedule
Program
Abstracts
List of Participants

1
3
6
16
42

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1. Information
Lecture rooms:
The plenary talks are given at Room 420 on the 4th floor. Parallel sessions take placein 3 rooms: Room 420, Room 111 and Room 110 (both Rooms 111 and 110 are on
the 1st floor).
Registration:
When you arrive at the conference, please input your information (name, aﬃliationand email address) at one of the terminals at the backside of Rooms 420, 111 and110. Further, please take your name card and a copy of program and abstract at theentrance of Room 420 (in front of the room or in the room).
To participants from China and Korea: Please go to Room 103 on the 1st floor at
13:00–14:00 on February 19th (Monday) to make the procedure of your visit. If
you can not visit there at that time, please go to Room 104 (International Research
Support Oﬃce (RIMS secretary)) on the 1st floor when you arrive at the conference.
To participants who attend banquets and/or excursion: Please go to Room 103 on the
1st floor at 13:00–14:00 on February 19th (Monday) to confirm your attendance ofbanquets and/or excursion. If you can not visit there at that time, please contact a
local organizer when you arrive at the conference.
Internet connection:
The eduroam wireless network is available on site. If you have some problems related
to eduroam, please contact your home institution’s technical support.
Banquets:
We have banquets in the cafe restaurant Camphora (in the campus of Kyoto University) at 18:00 on February 19th (Monday) and, in the restaurant Monsieur ITOH
(near Kawaramachi-Sanjo crossing) at 19:00 on February 22th (Thursday). We ask
the participants of the banquets to go there at that time. For the location of Camphoraand Monsieur ITOH, please see the map of them distributed at the conference.
We ask the participants of the conference to arrange the other meals by yourself.
Excursion:
We have an excursion in the afternoon on February 22th (Thursday). We ask theparticipants of the excursion to go to the entrance of RIMS at 13:00 on February 22th
(Thursday).

1

Notice for participants in the morning:
In plenary talks in the morning, Room 420 will be very crowded. In order to avoid
high density of people in Room 420 (to prevent infection), we show live streamings ofplenary talks at screens of Room 111 and Room 110. Please also use Room 111 andRoom 110 to listen plenary talks to avoid high density of people in Room 420.
Notice for speakers:
Speakers are supposed to give their presentations at RIMS.
A speaker can give a talk by either of the following three method. We recommend aspeaker to give a talk by the method (1).
(1) A speaker gives a talk by a slide of a pdf file. In this case, please copy the
pdf file of your slide to the PC at the lecture room in advance (in the teatime before your block), and please give a talk by using this PC. (This PC
is connected to the PC projector of the lecture room, and this PC is also
connected to Zoom via RIMS wifi.)(2) A speaker can give a talk by his/her own PC. (We do not recommend
this method.) In this case, please connect your PC to the PC projector inadvance, and please login Zoom via RIMS wifi in advance. In this case, youneed eduroam or a computer account of RIMS to login Zoom in advance. If
you need a computer account of RIMS, please let the local organizer(eacgt2024@kurims.kyoto-u.ac.jp) know this in advance.
(3) A speaker can give a talk by using blackboard at the lecture room. In thiscase, we distribute live streaming of the talk to online participants via Zoom.
Notice for online participants:
During a talk, please let your sound oﬀ (mute).
At the end of a talk, you can ask questions via Zoom, letting your sound on.
Please do not record the live streaming of a talk.
Notice for chairpersons:Please ask the speakers of your block to copy the pdf files of the talks to the PC at
the lecture room in advance (in the tea time before your block).
For further information, please see the conference web page:https://www.kurims.kyoto-u.ac.jp/~eacgt/

22. Talk Schedule
February 19 (Monday)
Chair
9:45–10:30
10:45–11:30

Room 420 (live streaming are available at Rooms 111 and 110)
Takahiro Kitayama
Thang T. Q. Le
Honghao Gao

11:30–13:00

Lunch

13:00–14:00

Room 103
Registration

Chair

Room 420
Yi LiuRoom 111
Ruifeng Qiu

14:00–14:20

Andrew Kricker

Toshio Saito

14:25–14:45
14:50–15:10

Kouki Yamaguchi
Leo Yoshioka

Motoo Tange
Sungmo Kang

Jean-Baptiste
Bellynck
Jiming Ma
Junseok Kim

15:10–15:40

Tea Time
Noboru Ito

Eiko Kin

Zhiyun Cheng

Carl-Fredrik
Nyberg-Brodda
Dounnu Sasaki
Ryoga Furutani(blanc)Chair

Thang T. Q. Le

15:40–16:00 Fengling Li

16:05–16:25 Kyungbae Park
Naoko Kamada
16:35–16:55 Katsumi Ishikawa
Yanqing Zou
17:00–17:20 Stavros Garoufalidis Youlin Li
18:00–20:00

Banquet3

Room 110
Tetsuya ItoFebruary 20 (Tuesday)
Chair
9:45–10:30
10:45–11:30

Room 420 (live streaming are available at Rooms 111 and 110)
Naoko Kamada
Inasa Nakamura
Seungwon Kim

11:30–13:00

Lunch

Chair
13:00–13:20
13:25–13:45
13:50–14:10

Room 420
Kimihiko Motegi
Gyo Taek Jin
Hajime Kubota
Seonmi Choi

14:10–14:40

Tea Time

Room 111
Kazuhiro Ichihara
Bin YuEiko Kin
Shunsuke Kano

Room 110
Ayumu Inoue
Kokoro Tanaka
Naoki Kimura
Jin Kosaka

Chair
Takuya Sakasai
14:40–15:00 Ying Zhang
15:05–15:25 Yue Gao

Motoo Tange
Jung Hoon Lee
Erika Kuno

15:30–15:50 Ryo Matsuda

Sangbum Cho

Makoto Ozawa
Junhua Wang
Noboru Ito
Kamolphat
Intawong

15:50–16:20

Tea Time

Chair
16:20–16:40
16:45–17:05
17:15–17:35
17:40–18:00

Jiajun Wang
Xiliu Yang
Zhechi Cheng
Tatsumasa Suzuki
Langte Ma

Sang-hyun Kim
Xiaobing Sheng
Akihiro Takano
Gye-Seon Lee
Minkyu Kim

4

Wataru Yuasa
Jun Ueki
Sohei Tateno
Jinho Jeoung
Andreani Petrou

February 21 (Wednesday)
Chair
9:45–10:30
10:45–11:30

Room 420 (live streaming are available at Rooms 111 and 110)
Kouichi Yasui
Noriyuki Hamada
Shicheng Wang

11:30–13:00

Lunch

Chair
13:00–13:20
13:25–13:45
13:50–14:10

Room 420
Noriyuki Hamada
Min Hoon Kim
Yohei Wakamaki
Natsuya Takahashi

14:10–14:40

Tea Time

Chair
14:40–15:00
15:05–15:25
15:30–15:50

Ying Zhang
Wenyuan Yang
Kento Sakai
Wonyong Jang

15:50–16:20

Tea Time

Chair
16:20–16:40
16:45–17:05
17:10–17:30

Takahiro Kitayama
Takuya Sakasai
Ingrid Irmer
Hongtaek Jung

Room 111
Tetsuya Ito
Xiaolei Wu
Wonjun Chang
Zhongzi Wang

Room 110
Jun Murakami
Fengchun Lei
Haimiao Chen
Hiroaki Karuo

Kokoro Tanaka
Yongju Bae
Ayumu Inoue
Mai Sato

Seiichi Kamada
Byeorhi Kim
Zixi Wang
Jumpei Yasuda

Jae Choon Cha
Se-Goo Kim
Sungkyung Kang
Jaewon Lee

Yuya Koda
Makoto Ozawa
Katsunori Arai
Naoyuki Monden

February 22 (Thursday)
Chair
9:45–10:30
10:45–11:30

Room 420 (live streaming are available at Rooms 111 and 110)
Takuya Sakasai
Kazuhiro Ichihara
Sang-hyun Kim

11:30–13:00
13:00–19:00
19:00–21:00

Lunch
Excursion
Banquet53. ProgramFebruary 19 (Monday)
ROOM 420 (live streaming are available at Rooms 111 and 110)Chair: Takahiro Kitayama
9:45–10:30 Thang T. Q. Le (Georgia Institute of Technology)
Quantum trace map for SLn skein algebras of surfaces
10:45–11:30 Honghao Gao (Tsinghua University)
Legendrian knots and Lagrangian fillings
ROOM 103
13:00–14:00

Registration

ROOM 420
Chair: Yi Liu
14:00–14:20 Andrew Kricker (Nanyang Technological University)
Circle-valued angle structures on ideal triangulations and the meromorphic 3D
index
14:25–14:45 Kouki Yamaguchi (Kyoto University)
On the 3-loop polynomial of genus 1 knots with trivial Alexander polynomial
14:50–15:10 Leo Yoshioka (The University of Tokyo)
Non-trivial cycles of the spaces of long embeddings detected by 2-loop graphs
Chair: Thang T. Q. Le
15:40–16:00 Fengling Li (Dalian University of Technology)
New polynomial invariants for knotoids
16:05–16:25 Kyungbae Park (Kangwon National University)
Alexander polynomial of twisted torus knots
16:35–16:55 Katsumi Ishikawa (Kyoto University)
The trapezoidal conjecture for links of braid index 3
17:00–17:20 Stavros Garoufalidis (Southern University of Science and Technology)
Multivariable knot polynomials from braided Hopf algebras with
automorphisms

6

ROOM 111
Chair: Ruifeng Qiu
14:00–14:20 Toshio Saito (Joetsu University of Education)
Exceptional or half-integral chirally cosmetic surgeries
14:25–14:45 Motoo Tange (University of Tsukuba)
Lens space surgeries on homology spheres of λ = −2, −3
14:50–15:10 Sungmo Kang (Chonnam National University, Mathematics
Education)
Hyperbolic tunnel-number-one knots with Seifert-fibered Dehn surgeries
Chair: Noboru Ito
15:40–16:00 Zhiyun Cheng (Beijing Normal University)
Intersection graph and writhe polynomial
16:05–16:25 Naoko Kamada (Nagoya City University)
An invariant of twisted knots
16:35–16:55 Yanqing Zou (Tongji University)
Some results of tunnel numbers of satellite knots
17:00–17:20 Youlin Li (Shanghai Jiao Tong University)
Strongly exceptional Legendrian connected sum of two Hopf links

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ROOM 110Chair: Tetsuya Ito
14:00–14:20 Jean-Baptiste Bellynck (Osaka University)
Visualizing Cayley graphs of finitely presented groups using force-directed graphalgorithms
14:25–14:45 Jiming Ma (Fudan University)
Complex hyperbolic quadrangle groups
14:50–15:10 Junseok Kim (KAIST)A subgroup of Out(RAAG) and its acylindrical hyperbolicity
Chair: Eiko Kin
15:40–16:00 Carl-Fredrik Nyberg-Brodda (KIAS)
On the freeness problem for parabolic subgroups of SL(2, C)
16:05–16:25 Dounnu Sasaki (Gakushuin University)
Counting subgroups via Mirzakhani’s curve counting
16:35–16:55 Ryoga Furutani (Hiroshima University)
Divides and hyperbolic volumes
17:00–17:20 (blanc)
18:00–20:00

Banquet8February 20 (Tuesday)
ROOM 420 (live streaming are available at Rooms 111 and 110)Chair: Naoko Kamada
9:45–10:30 Inasa Nakamura (Saga University)
Knitted surfaces in the 4-ball and their graphical description
10:45–11:30 Seungwon Kim (Sungkyunkwan University)
Knotted handlebody links in the 4-sphere
ROOM 420
Chair: Kimihiko Motegi
13:00–13:20 Gyo Taek Jin (KAIST)
Minimal grid diagrams of prime knots with crossing number 14 and arc
index 13
13:25–13:45 Hajime Kubota (Kyoto University)
Grid homology for spatial graphs and a Kunneth formula of connected sums
13:50–14:10 Seonmi Choi (Kyungpook National University)
Mosaics for immersed surface-links
Chair: Takuya Sakasai
14:40–15:00 Ying Zhang (Soochow University)
Length minima for an infinite family of filling closed curves on a one-holed torus
15:05–15:25 Yue Gao (Anhui Normal University)
An upperbound for the number of critical points of the systole function on thesurface moduli space
15:30–15:50 Ryo Matsuda (Kyoto University)
Maximal cusps are not dense for the infinite-dimensional Teichmüller spaces
Chair: Jiajun Wang
16:20–16:40 Xiliu Yang (Peking University)
Knot Floer homology and the fundamental group of (1,1) knots
16:45–17:05 Zhechi Cheng (Wuhan University)
Combinatorial aspects of symplectic Khovanov homology
17:15–17:35 Tatsumasa Suzuki (Tokyo Institute of Technology)
The d-invariants of Brieskorn homology 3-spheres with almost simple linear
graphs17:40–18:00 Langte Ma (Shanghai Jiao Tong University)
Homology S 1 × S 3 and TQFT
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ROOM 111
Chair: Kazuhiro Ichihara
13:00–13:20 Bin Yu (Tongji University)
Self orbit equivalences on a class of Anosov flows
13:25–13:45 Eiko Kin (Osaka University)
Complete description of Agol cycles of pseudo-Anosov 3-braids
13:50–14:10 Shunsuke Kano (Tohoku University, MathCCS)
Train track combinatorics and cluster algebras
Chair: Motoo Tange
14:40–15:00 Jung Hoon Lee (Jeonbuk National University)
Primitive curve complex for a handlebody
15:05–15:25 Erika Kuno (Osaka University)
Automorphisms of fine curve graphs for nonorientale surfaces
15:30–15:50 Sangbum Cho (Hanyang University)
Homotopy primitive disk complexes
Chair: Sang-hyun Kim
16:20–16:40 Xiaobing Sheng (Okinawa Institute of Science and Technology)
Some experimental results of knots and links constructed from Thompson’sgroup F a la Jones
16:45–17:05 Akihiro Takano (The University of Tokyo)
The p-colorable subgroup of Thompson’s group F
17:15–17:35 Gye-Seon Lee (Seoul National University)
Convex cocompactness for Coxeter groups
17:40–18:00 Minkyu Kim (KIAS)
Analyticity and primitivity of exponential functors on free groups

10ROOM 110Chair: Ayumu Inoue
13:00–13:20 Kokoro Tanaka (Tokyo Gakugei University)
The second quandle homology group of the knot n-quandle
13:25–13:45 Naoki Kimura (Waseda University)
Invariants of Legendrian knots derived from generalizations of racks
13:50–14:10 Jin Kosaka (Osaka University)
On classification of finite generalized Alexander quandles
Chair: Makoto Ozawa
14:40–15:00 Junhua Wang (Jiangsu University of Technology)
Small diﬀerence between tunnel numbers of cable knots and their companions
15:05–15:25 Noboru Ito (National Institute of Technology, Ibaraki College)
Integrating curvature and quantized Arnold strangeness
15:30–15:50 Kamolphat Intawong (National Institute of Technology, Ibaraki
College)
Knot theory and its application to authentication technology
Chair: Wataru Yuasa
16:20–16:40 Jun Ueki (Ochanomizu University)
Profinite rigidity of the multivariable Alexander polynomials of links
16:45–17:05 Sohei Tateno (Nagoya University)
On the Iwasawa-type formula for Zdp -covers of links
17:15–17:35 Jinho Jeoung (Seoul National University)
PGL2 (Qp )-orbit closures on a p-adic homogeneous space of infinite volume
17:40–18:00 Andreani Petrou (OIST)
Factorisation of the Harer-Zagier transform for HOMFLY-PT polynomials

11

February 21 (Wednesday)
ROOM 420 (live streaming are available at Rooms 111 and 110)Chair: Kouichi Yasui
9:45–10:30 Noriyuki Hamada (Kyushu University)
Exotic 4-manifolds with signature zero
10:45–11:30 Shicheng Wang (Peking University)
Some connections between topology and number theory
ROOM 420
Chair: Noriyuki Hamada
13:00–13:20 Min Hoon Kim (Kyungpook National University)
Calegari homotopy 4-spheres are standard
13:25–13:45 Yohei Wakamaki (Osaka University)
Stabilizations of some small exotic rational surfaces
13:50–14:10 Natsuya Takahashi (Osaka University)
Exotic 4-manifolds with small trisection genus
Chair: Ying Zhang
14:40–15:00 Wenyuan Yang (Peking University)
Limit sets for branching random walks on relatively hyperbolic groups
15:05–15:25 Kento Sakai (Osaka University)
Degeneration of hyperbolic ideal polygons along harmonic map rays
15:30–15:50 Wonyoung Jang (KAIST)On the kernel of group actions on asymptotic cones
Chair: Takahiro Kitayama
16:20–16:40 Takuya Sakasai (The University of Tokyo)
On groups of Kim-Manturov
16:45–17:05 Ingrid Irmer (Southern University of Science and Technology)
Schmutz-Thurston duality
17:10–17:30 Hongtaek Jung (Seoul National University)
Volumes of Hitchin-Riemann moduli spaces are infinite

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ROOM 111
Chair: Tetsuya Ito
13:00–13:20 Xiaolei Wu (Fudan University)
Compactly-supported classes in the homology of big mapping class groups
13:25–13:45 Wonjun Chang (POSTECH)
The generalized Harer conjecture for the homology triviality
13:50–14:10 Zhongzi Wang (Peking University)
Extendability over the 4-sphere and invariant spin structures of surface
automorphisms
Chair: Kokoro Tanaka
14:40–15:00 Yongju Bae (Kyungpook National University)
The chromatic index of links
15:05–15:25 Ayumu Inoue (Tsuda University)
A relationship between quandle homologies and relative group homologies,
from the view point of Seifert (hyper) surfaces
15:30–15:50 Mai Sato (Tsuda University)
Equivalence classes of RotE2 -colorings of a diagram of a torus knot
Chair: Jae Choon Cha
16:20–16:40 Se-Goo Kim (Kyung Hee University)
Double slice genera and rho-invariants of knots
16:45–17:05 Sungkyung Kang (University of Oxford)
Finding exotic disks via satellite operations
17:10–17:30 Jaewon Lee (KAIST)
Obstructing 2-torsion in the rational concordance group

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ROOM 110Chair: Jun Murakami
13:00–13:20 Fengchun Lei (Dalian University of Technology)
On H ′ -splittings of handlebodies
13:25–13:45 Haimiao Chen (Beijing Technology and Business University)
Torsion in Kauﬀman bracket skein module of a 4-strand Montesinos knot
exterior
13:50–14:10 Hiroaki Karuo (Gakushuin University)
On positivity of Roger–Yang skein algebras
Chair: Seiichi Kamada
14:40–15:00 Byeorhi Kim (POSTECH)
On light bulb theorem for immersed surfaces
15:05–15:25 Zixi Wang (Zhejiang Normal University)
Profinite rigidity and flexibility of some branched twisted spin 2-knots
15:30–15:50 Jumpei Yasuda (Osaka University)
Alexander theorem on surfaces in the 4-ball using knitted surfaces
Chair: Yuya Koda
16:20–16:40 Makoto Ozawa (Komazawa University)
Critical complexes for the 3-sphere16:45–17:05 Katsunori Arai (Osaka University)
Cohomology of groupoid racks for spatial surfaces
17:10–17:30 Naoyuki Monden (Okayama University)
Ruled surfaces and indecomposable Lefschetz fibrations

14February 22 (Thursday)
ROOM 420 (live streaming are available at Rooms 111 and 110)Chair: Takuya Sakasai
9:50–10:30 Kazuhiro Ichihara (Nihon University)
Boundary slopes (nearly) bound exceptional slopes
10:45–11:30 Sang-hyun Kim (KIAS)
The first order ridigity of manifold diﬀeomorphism groups
13:00–19:00
19:00–21:00

Excursion
Banquet15

4. Abstracts
Plenary talks
Honghao Gao Tsinghua University
Title: Legendrian knots and Lagrangian fillings
Abstract: Legendrian knots and their exact Lagrangian fillings are central objects
to study in low dimensional contact and symplectic topology. Therefore, it is an
important question to classify exact Lagrangian fillings up to Hamiltonian isotopy.
It is conjectured that this classification is controlled by a quiver and some derived
algebraic structures. In this talk, I will review the historical developments, and explain
the algebraic machinery to distinguish fillings. Then, I will discuss the ideas to obtaina subjectivity result, which involving new ideas such as understanding polygons on
surfaces, quiver with potentials, etc. This is based on a joint work with Roger Casals.

Noriyuki Hamada Kyushu University
Title: Exotic 4-manifolds with signature zero
Abstract: We will talk about our recent construction of infinitely many simplyconnected closed exotic symplectic 4-manifolds with signature zero, which are homeomorphic but not diﬀeomorphic to #2k+1 (S 2 ×S 2 ) and #2l+1 (CP2 # CP2 ) for each k ≥ 5and l ≥ 4, respectively. Notably, they provide the smallest such exotic 4-manifolds
known to date. Moreover, they populate some new lattices in symplectic geographyof simply-connected minimal symplectic 4-manifolds of general type. We build our
examples from scratch: first, construct fairly special small Lefschetz fibrations overtori with signature zero, take fiber sum with the trivial fibration over a torus, andthen apply surgeries along Lagrangian tori to kill π1 . This is joint work with Inanc
Baykur (University of Massachusetts Amherst).

Kazuhiro Ichihara Nihon University
Title: Boundary slopes (nearly) bound exceptional slopes
Abstract: For a hyperbolic knot in the 3-sphere, we say a non-meridional slope is
exceptional if Dehn surgery on that slope results in a non-hyperbolic manifold. We
provide evidence in support of two conjectures. The first (inspired by a questionof Kimihiko Motegi) states that any exceptional surgery slope occurs in the intervalbounded by the least and the greatest finite boundary slopes. Secondly, when there
are exceptional surgeries, we conjecture there are (possibly equal) NIT (meaning that
non-integral or toroidal) boundary slopes b1 ≤ b2 so that the exceptional slopes lie
16

in [⌊b1 ⌋, ⌈b2 ⌉]. Moreover, if ⌈b1 ⌉ ≤ ⌊b2 ⌋, the integers in the interval [⌈b1 ⌉, ⌊b2 ⌋] areall exceptional surgeries. This talk is based on a joint work with Thomas Mattman(California State University, Chico).

Sang-hyun Kim KIAS
Title: The first order ridigity of manifold diﬀeomorphism groups
Abstract: Two groups are elementarily equivalent if they have the same sets of true
first order group theoretic sentences. We prove that if the homeomorphism groups oftwo compact connected manifolds are elementarily equivalent, then the manifolds are
homeomorphic. This generalizes Whittaker’s theorem on isomorphic homeomorphismgroups (1963) without relying on it. Joint work with Thomas Koberda (UVa) andJavier de la Nuez-Gonzalez (KIAS).

Seungwon Kim Sungkyunkwan University
Title: Knotted handlebody links in the 4-sphere
Abstract: In dimension 3, the following two theorems are well known: first, any two
Seifert surfaces bounded by the unknot are isotopic, and second, any two splitting
spheres of the 2-component trivial link are isotopic.
Recently, Budney-Gabai found that the generalization of the first theorem to dimension 4 is false , i.e., there are infinitely many 3-balls bounded by the trivial 2-knotin the 4-sphere. In this talk, I will talk about the generalization of Budney-Gabai’s
theorem to higher genus surface links. First, I will show that there exists a pair ofhandlebodies of genus greater than equal to two, bounded by the trivial surface knot
in the 4-sphere, which are not isotopic rel. boundary. I will also talk about the existence of 3-dimensional handlebody links in the 4-sphere that are not isotopic relative
to the boundary by showing that there are non isotopic splitting spheres for trivial
surface links. This talk is based on joint works with Mark Hughes and Maggie Miller.

Thang T. Q. Le Georgia Institute of Technology
Title: Quantum trace map for SLn skein algebras of surfaces
Abstract: For a punctured surface there are two quantizations of the SLn character
variety. The first quantization is the SLn skein algebra, and the second one is the FockGoncharov’s quantization of the higher Teichmuller space. When n = 2 Bonahon andWong showed that there is an algebra homomorphism, called the quantum trace, fromthe first quantized algebra to the second one. On the classical level the map expresses
the trace of a curve in terms of Thurston’s shear coordinates of the Teichmuller space.
17

We show a similar quantum trace map exists for SLn . This is a joint work with T.
Yu.

Inasa Nakamura Saga University
Title: Knitted surfaces in the 4-ball and their graphical description
Abstract: Knits (or BMW tangles) are tangles in a cylinder generated by generatorsof the BMW (Birman-Murakami-Wenzl) algebras, consisting of standard generatorsof the braid group and their inverses, and splices of crossings called pairs of hooks.
We give a new construction of surfaces in D2 × B 2 , called knitted surfaces (or BMW
surfaces), that are described as the trace of deformations of knits, and we give thenotion of charts for knitted surfaces, that are graphs in B 2 . We show that a knitted
surface has a chart description. Knitted surfaces and their chart description include
2-dimensional braids and their chart description. This is joint work with Jumpei
Yasuda (Osaka University).

Shicheng Wang Peking University
Title: Some connections between topology and number theory
Abstract: We will discuss some connections between topology and number theory
inspired by the studies of mapping degrees and achirality of manifolds.

18

Parallel Session

Katsunori Arai Osaka University
Title: Cohomology of groupoid racks for spatial surfaces
Abstract: A spatial surface is a compact surface embedded in the 3-sphere. We
assume that each connected component has non-empty boundary. Oriented spatial
surfaces are represented by using trivalent spines and their diagrams. In this talk, we
introduce the cohomology theory for groupoid racks and define cocycle invariants oforiented spatial surfaces, where a groupoid rack is an algebraic structure that can beused for colorings of diagrams of oriented spatial surfaces.

Yongju Bae Kyungpook National University
Title: The chromatic index of links
Abstract: Knots and links can be classified by the quandle colorability. For thecolorable knots or links, there are various quandle invariants for finer classification
e.g. the number of colorings, quandle cocycle invariants, etc. Unfortunately, there
are no particular method to study the non-colorable knots at the moment. In thistalk, we are going to introduce a new invariant, called the chromatic index of links,
which is designed for studying non-colorable knots. We will try to show relationshipbetween the chromatic index and the other known knot invariants; crossing number,
braid index and bridge number, etc.

Jean-Baptiste Bellynck Osaka University
Title: Visualizing Cayley graphs of finitely presented groups using force-directed
graph algorithms
Abstract: In this presentation, I will discuss an implementation of a program visualizing group presentations as Cayley graphs. I will explore diﬀerent approaches,
drawing comparisons with similar projects in the field. I will delve into one specificapproach that utilizes a force-directed graph drawing algorithm specifically refitted
for groups.
I will explain how the application might be used in university-level teaching to approach group theory from the perspective of symmetry operations on geometric objects
as done in Carter’s work. [Carter, 2009]. The drawn Cayley graphs make it possible
to build up a graph theoretic intuition of various concepts like subgroups, quotientgroups, growth of groups or word problem for groups.
19

Finally, since every finitely presented group can be generated in this manner, I will
touch on how the software might be useful in experimental research of finitely presented groups.

Wonjun Chang POSTECH
Title: The generalized Harer conjecture for the homology triviality
Abstract: The classical Harer conjecture concerns the stable homology triviality ofthe evident embedding from braid groups to mapping class groups, a result establishedby Song and Tillmann. The main part of the proof is to show that the map inducedon the plus construction of its classifying spaces (of their direct limits) is a double
loop space map. In this talk, we present a proof of the generalized Harer conjecture,
which extends the homology triviality to every (regular) embedding from braid groups
to mapping class groups. The main strategy employed in the proof is to remove all
the interchangeable subsurfaces and collapse the new boundary components. Then we
get a covering space over a disk with marked points, which we know how to handle.
The final goal is to show that the map induced on their classifying spaces preserves
the actions of the framed little 2-disks operad.

Haimiao Chen Beijing Technology and Business University
Title: Torsion in Kauﬀman bracket skein module of a 4-strand Montesinos knot exterior
Abstract: For a 3-manifold M , let S(M ) denote its Kauﬀman bracket skein module. Problem 1.92 (G) (i) in the Kirby’s list asks whether S(M ) is free when M isirreducible and has no incompressible non-parallel to the boundary torus. We answer
this negatively by showing that S(M ) contains torsion when M is the complement ofa 4-strand Montesinos knot in the 3-sphere.

Zhechi Cheng Wuhan University
Title: Combinatorial aspects of symplectic Khovanov homology
Abstract: Symplectic Khovanov homology is a link invariant defined with symplectic
geometry. It behaves similarly to Khovanov homology, so Its comparison with the
Khovanov homology remains an interesting question. In 2020, Abouzaid and Smith
proved that symplectic Khovanov homology is isomorphic to Khovanov homology overcharacteristic-zero fields, while the more general cases remain open. In this talk, I
will discuss sone recent progress on the topic in non characteristic-zero fields.

20

Zhiyun Cheng Beijing Normal University
Title: Intersection graph and writhe polynomial
Abstract: In this talk, I will explain the relation between the intersection graph ofa chord diagram and the writhe polynomial of the corresponding virtual knot.

Sangbum Cho Hanyang University
Title: Homotopy primitive disk complexes
Abstract: Given a Heegaard splitting of the 3-sphere, the primitive disk complex isdefined to be the full subcomplex of the disk complex for one of the handlebodies of the
splitting, spanned by the vertices of primitive disks. It is an open question whether theprimitive disk complex is connected or not when the genus of the splitting is greaterthan three. In this talk, we prove that a quotient of the primitive disk complex, called
the homotopy primitive disk complex, is connected.

Seonmi Choi Kyungpook National University
Title: Mosaics for immersed surface-links
Abstract: The concept of a knot mosaic was introduced by Lomonaco and Kauﬀman
as a means to construct a quantum knot system. The mosaic number of a given knot
K is defined as the minimum integer n that allows the representation of K on an n×n
mosaic board. Building upon this, Nelson and I generalized the knot mosaic system
for surface-links using marked graph diagrams and gave the lower and upper boundsof the mosaic number of the surface-links in Yoshikawa’s table. In this talk, we definea mosaic system for immersed surface-links using singular marked graph diagrams anddiscuss the mosaic number of immersed surface-links. This is joint work with Jieon
Kim.

Ryoga Furutani Hiroshima University
Title: Divides and hyperbolic volumes
Abstract: A divide is a concept introduced by A’Campo as part of his study oncomplex plane curve singularities. Each divide defines a link in the 3-sphere called
the link of the divide. In this talk, we reconstruct the complement of the link of adivide according to the combinatorial structure of the divide. As a consequence, weshow that the complement of the link of a prime divide can be obtained by Dehn
filling a hyperbolic 3-manifold that admits a decomposition into several ideal regulartetrahedra, octahedra and cuboctahedra. This immediately gives an upper bound of21

the hyperbolic volume of the link of a divide. In addition, we show that the upperbound given here is asymptotically sharp. This is joint work with Y.Koda.

Yue Gao Anhui Normal University
Title: An upperbound for the number of critical points of the systole function on thesurface moduli space
Abstract: We obtain an upper bound for the number of non-isometric critical pointsof the systole function on Tg . Besides, we obtain an upper bound for the number of
those critical points whose systole is smaller than a constant.

Stavros Garoufalidis Southern University of Science and Technology
Title: Multivariable knot polynomials from braided Hopf algebras with automorphisms
Abstract: We will discuss a unified approach to define multivariable polynomial invariants of knots that include the colored Jones polynomials, the ADO polynomials
and the invariants defined using the theory of quantum groups. Our constructionuses braided Hopf algebras with automorphisms. We will give examples of 2-variable
invariants, and discuss their structural properties. Joint work with Rinat Kashaev.

Ayumu Inoue Tsuda University
Title: A relationship between quandle homologies and relative group homologies,
from the view point of Seifert (hyper) surfaces
Abstract: Associated with a triple of a group G, its automorphism φ, and its subgroup H satisfying a certain condition, we have a quandle X = (G, H, φ). In this talk,we see that we have a chain map from the (twisted) quandle chain complex CnQ (X)Zto the (Adamson/Hochschild) relative group chain complex Cn ([G : H]). Utilizing
this chain map, we have a 2-cocycle of the knot quandle of a fibered knot which maps
the fundamental class to the area of the fiber. We further see that each connected
sum of the m-twist-spun trefoil and a surface knot, whose triple point number is zero,is not reversible and not negative amphicheiral if 2 ≤ m ≤ 5.

Kamolphat Intawong National Institute of Technology, Ibaraki College
Title: Knot theory and its application to authentication technology
Abstract: In the information society, it is essential to continue developing information security technology. Recently, various approaches, such as quizzes, have been
22

taken. In the past years, we have been studying knot theory and introducing new
functions implying invariants to distinguish some knots and links. One of the functions we introduced has a specific characteristic that enables it to accomplish the
purpose with surprisingly less calculation time. In this study we apply this function:
the multiple linking number T to create quizzes for authentication.

Ingrid Irmer Southern University of Science and Technology
Title: Schmutz-Thurston duality
Abstract: When constructing mapping class group-equivariant cell decompositionsof Teichmueller space, the theory is greatly simplified by the existence of punctures
or at least marked points, relative to which it is possible to construct cell decompositions. Two people who have independently pioneered the study of mapping classgroup-equivariant cell decompositions of Teichmueller space of closed compact surfaces
without marked points are Schmutz and Thurston. In this talk it will be explainedthat there is a sense in which the two approaches are dual.

Katsumi Ishikawa Kyoto University
Title: The trapezoidal conjecture for links of braid index 3
Abstract: The trapezoidal conjecture is a classical famous conjecture posed by Fox,
which states that the coeﬃcient sequence of the Alexander polynomial of any alternating knot is trapezoidal. In this talk, we show this conjecture for knots and linksof braid index 3.

Noboru Ito National Institute of Technology, Ibaraki College
Title: Integrating curvature and quantized Arnold strangeness
Abstract: Arnold invariants, J − , J + and St, of plane curves are classical and wellknown. Two invariants J − and J + have been successfully quantized. The former wasquantized by Viro and the latter by Lanzat-Polyak. However, the Arnold invariant
St (Arnold strangeness) quantization remained unrealized. In this talk, we express
a quantization of St (Arnold strangeness) by integrating curvatures multiplied bydensities.

Wonyoung Jang KAIST
Title: On the kernel of group actions on asymptotic cones
Abstract: The concept of an asymptotic cone was first suggested by Gromov and he23

used it to establish Gromov’s polynomial growth theorem. An asymptotic cone of agroup reflects many properties of the group. For example, a group is virtually nilpotent
if and only if all of its asymptotic cones are locally compact (equivalently, proper).
Also, a finitely generated group is hyperbolic if and only if all of its asymptotic cones
are real trees. In this talk, we characterize the natural kernel of the action of agroup G on its asymptotic cone. Our main theorem states that if G is acylindrically
hyperbolic, then the kernel of G-action on an asymptotic cone of G is the sameas many algebraically defined subgroups. Moreover, this result does not depend on
the choice of ultrafilter and sequence that we need to define asymptotic cones so it
implies that the kernel is invariant under the choice of these. It is known that a group
may have distinct (actually, non-homeomorphic) asymptotic cones, and indeed someacylindrically hyperbolic groups also have various asymptotic cones. We also extend
this result by other spaces at “infinity”, for instance, the limit set of convergencegroup action, Floyd boundary, and many boundaries of CAT(0) spaces with someconditions. If time permits, we will introduce another action of G on an asymptotic
cone, called Paulin’s construction, and describe the kernel of Paulin’s construction.
This work is joint with my advisor, Hyungryul Baik.

Jinho Jeoung Seoul National University
Title: PGL2 (Qp )-orbit closures on a p-adic homogeneous space of infinite volume
Abstract: Let K be an unramified quadratic extension of Qp for a fixed p > 2.
Projective general linear groups G = PGL2 (K) and H = PGL2 (Qp ) act transitively
on Bruhat-Tits trees TG and TH , respectively. We identify G/H with the set of Hsubtrees G.TH . Let Γ be a Schottky subgroup such that Γ\TG is infinite volume andhas an additional condition named high-branchedness, and let Λ be its limit set.
We classify Γ-orbits in G/H. Let C = gC H ∈ G/H. As a generalization of Ratner’s
theorem, if Γ\gC .TH meets the convex core of Γ\TG , then the Γ-orbit of C is either
dense or closed in CΛ = {gH : ∂(g.TH ) ∩ Λ ̸= ∅}.

Gyo Taek Jin KAIST
Title: Minimal grid diagrams of prime knots with crossing number 14 and arc index
13
Abstract: There are 46,972 prime knots with crossing number 14. Among them
19,536 are alternating and have arc index 16. Among the non-alternating knots,
17,477, and 3,180 have arc index 10, 11, and 12, respectively. The remaining 23,762
have arc index 13 or 14. There are none with arc index 15 or larger. We used the24Dowker-Thistlethwaite code of the 23,762 knots provided by the program Knotscapeto locate non-alternating edges in their diagrams. Our method requires at least six
non-alternating edges to find arc presentations with 13 arcs. We obtained 7,504 knots
having arc index 13. We show them by their minimal grid diagrams. It is a joint workwith Hwa Jeong Lee, Alexander Stoimenow, Minchae Kim, Songwon Ryu, Dongju
Shin, and Hun Kim.

Hongtaek Jung Seoul National University
Title: Volumes of Hitchin-Riemann moduli spaces are infinite
Abstract: Let Hitn (S) be the PSL(n, R)-Hitchin component of a compact surface
S with negative Euler characteristic and let M od(S) be the mapping class group.
We discuss the Atiyah-Bott-Goldman volumes of the Hitchin-Riemann moduli spaces
Hitn (S)/M od(S). When n = 2, M. Mirzakhani proved that the Atiyah-Bott-Goldman
volume, or equivalently the Weil-Petersson volume, of Hit2 (S)/M od(S) is finite. On
the contrary, we show that the volumes of Hitn (S)/M od(S) are infinite providedn > 2. This is joint work with Suhyoung Choi.

Naoko Kamada Nagoya City University
Title: An invariant of twisted knots
Abstract: Twisted knots correspond to stable equivalence classes of thickened (possibly, non-orientable) surfaces. They are a generalization of virtual knots. The odd
writhe is an invariant of virtual knots defined by Kauﬀman. The n writhe and index
polynomials are extensions of the odd writhe. In this talk, we discuss an invariant of
twisted knots, which is related to the n writhe and index polynomials.

Sungkyung Kang University of Oxford
Title: Finding exotic disks via satellite operations
Abstract: Given a pair of slice disks which might not even be topologically isotopic, their (generalized) doubles are always topologically isotopic but potentially notsmoothly isotopic. We prove that if we started with a pair of disks which are distinguished by cobordism maps in hat-flavored knot Floer homology, then the doubled
disks are also distinguished in the same way. This gives the first general and flexible
method of constructing exotic disks from any nontrivial knot. We also show that thesame argument is in some cases possible also with Khovanov homology. This is a joint
work with Gary Guth, Kyle Hayden, and JungHwan Park.

25

Sungmo Kang Chonnam National University, Mathematics Education
Title: Hyperbolic tunnel-number-one knots with Seifert-fibered Dehn surgeries
Abstract: In this talk, I will present Seifert-fibered surgeries under some circumstances on hyperbolic tunnel-number-one knots are integral and are realized by primitive/Seifert positions. This result supports partially the two conjectures related toSeifert-fibered surgeries on hyperbolic knots: (1) Any Seifert-fibered surgeries on hyperbolic knots in the 3-sphere are integral, and (2) any Seifert-fibered surgeries onhyperbolic tunnel-number-one knots can be realized by a primitive/Seifert position
whose surface slope corresponds to the surgery slope.

Shunsuke Kano Tohoku University, MathCCS
Title: Train track combinatorics and cluster algebras
Abstract: The concepts of train track was introduced by W. P. Thurston to study
the measured foliations/laminations and the pseudo-Anosov mapping classes on asurface. In this talk, we translate some concepts of train tracks into the languageof cluster algebras using the tropicalization of Goncharov–Shen’s potential function.
Using this, we translate a combinatorial property of a train track associated witha pseudo-Anosov mapping class into the combinatorial property in cluster algebras,
called the sign stability which was introduced by Tsukasa Ishibashi and the speaker.

Hiroaki Karuo Gakushuin University
Title: On positivity of Roger–Yang skein algebras
Abstract: The positivity conjecture of skein algebras is an intriguing topic inspiredby (quantum) cluster algebras. The conjecture asserts that the “bracelets basis” over
the Laurent polynomial ring Z[q ±1 ] is a positive basis i.e. has structure constants inZ≥0 [q ±1 ]. It is known the bracelets basis forms a “lower bound” among the positive
bases of the skein algebra. In this talk, we show similar results for Roger–Yang skein
algebras, which are related to decorated Teichmüller spaces and cluster algebras ofpunctured surfaces.

Byeorhi Kim POSTECH
Title: On light bulb theorem for immersed surfaces
Abstract: The classical light bulb trick states that a knot smoothly embedded in
S 2 × S 1 that intersects a S 2 × {y} transversally exactly one point is isotopic to thestandard vertical curve. In 2020, David Gabai generalized the classical light bulb
trick to embedded surfaces in 4-manifolds. In this talk, we will give an overview of26

Gabai’s 4-dimensional light bulb theorem and generalize it to immersed surfaces in
4-manifolds.

Junseok Kim KAIST
Title: A subgroup of Out(RAAG) and its acylindrical hyperbolicity
Abstract: In this talk, I will introduce a finite index normal subgroup of the outerautomorphism group of right-angled Artin group generated by transvections and partial conjugations. In order to check whether this group is acylindrically hyperbolic ornot, we will discuss some interesting algebraic structure of it when the defining graphof right-angled Artin group is connected.

Min Hoon Kim Kyungpook National University
Title: Calegari homotopy 4-spheres are standard
Abstract: In 2009, D. Calegari constructed smooth homotopy 4-spheres for eachfibered knot in the 3-sphere. In this talk, we show that all of them are diﬀeomorphic
to the 4-sphere.

Minkyu Kim KIAS
Title: Analyticity and primitivity of exponential functors on free groups
Abstract: Functors on the category gr of finitely generated free groups and grouphomomorphisms appear naturally in diﬀerent contexts of topology. There are examples given by Hochschild-Pirashvili homology for wedge of circles, or functors on the
Habiro-Massuyeau category of Jacobi diagrams in handlebodies; as another example,
bivariant functors on gr provide natural coeﬃcients for the stable cohomology of automorphism groups of free groups. Some of these natural examples satisfy further
properties: they are analytic and/or exponential.
Pirashvili proves that the category of exponential contravariant functors from gr
to the category k-Mod of k-modules is equivalent to the category of cocommutative
Hopf algebras over k. Powell proves an equivalence between the category of analytic
contravariant functors from gr to k-Mod, and the category of linear functors on thelinear PROP associated to the Lie operad when k is a field of characteristic 0. In
this talk, after explaining these two equivalences of categories, I will explain how theyinteract with each other. We also go further by introducing primitive contravariant
functors on gr to extend the results to positive characteristic. This is a joint workwith Christine Vespa.

27

Se-Goo Kim Kyung Hee University
Title: Double slice genera and rho-invariants of knots
Abstract: We give a lower bound on the double slice genus of a knot using CheegerGromov-von Neumann rho-invariants. We obtain the lower bound from a new obstruction to embedding a closed 3-manifold with infinite cyclic first homology in aclosed 4-manifold with infinite cyclic fundamental group, preserving the first homology. As an application, we give knots with vanishing Casson-Gordon invariants whose
double slice genera are arbitrarily large. This is a joint work with Taehee Kim.

Naoki Kimura Waseda University
Title: Invariants of Legendrian knots derived from generalizations of racks
Abstract: Racks and quandles are algebraic systems which bring knot invariants.
In this talk, we introduce algebraic systems called a bi-Legendrian rack and a 4Legendrian rack, both of which are racks equipped with additional structures. We
explain these algebraic systems provide invariants of Legendrian knots.

Eiko Kin Osaka University
Title: Complete description of Agol cycles of pseudo-Anosov 3-braids
Abstract: The combinatorial isomorphism class of a periodic splitting sequence is
a complete conjugacy invariant of a pseudo-Anosov map associated to the stablemeasured lamination. An Agol cycle of a pseudo-Anosov map is a periodic part of aperiodic splitting sequence. Mosher defined a train track in a torus associated to a
Farey interval and investigated its properties including an intriguing relation between
the train track and the continued fraction expansion of a quadratic irrational number.
In this talk we study Mosher’s train track and give a complete description of the Agolcycles of pseudo-Anosov 3-braids. This is joint work with Keiko Kawamuro.

Jin Kosaka Osaka University
Title: On classification of finite generalized Alexander quandles
Abstract: Due to D. Joyce, for a given group and an automorphism of it, a quandle isconstructed, which we call a generalized Alexander quandle. Recently, A. Higashitaniand H. Kurihara has studied generalized Alexander quandles of finite groups. Although many generalized Alexander quandles can be classified using their theorem,
there exist quandles derived from groups of order more than 16 that do not satisfy
the assumptions of their theorem and cannot be classified. In this talk, I will present
the results of isomorphisms of these exceptional quandles.
28

Andrew Kricker Nanyang Technological University
Title: Circle-valued angle structures on ideal triangulations and the meromorphic 3D
index
Abstract: This talk will present some results concerning the space of S 1 -valued angle
structures on an ideal triangulation of a cusped 3-manifold. These structures wereintroduced by Feng Luo. The main theorem is that the connected components ofthis space are in a natural bijection with the elements of certain homology groups
associated to the manifold. The correspondence will be constructed geometrically byconsidering the obstruction theory problem of lifting boundary-parabolic representations of the fundamental group of the manifold to P SL(2, C) to boundary-unipotent
representations to SL(2, C). We will explain an application of these results to thestudy of the meromorphic 3D index of Garoufalidis and Kashaev. This is joint workwith Craig Hodgson and Rafael Siejakowski.

Hajime Kubota Kyoto University
Title: Grid homology for spatial graphs and a Kunneth formula of connected sums
Abstract: Grid homology is a combinatorial reconstruction of the knot Floer homology. There is an extension of grid homology for transverse spatial graphs, which
is known to be related to sutured Floer homology. In this talk, I will show that if
a spatial graph has a sink, source, or cut edge, then its grid homology is trivial.As
an application, I will give a purely combinatorial proof of a Künneth formula for the
knot Floer homology of connected sums in the framework of the grid homology.

Erika Kuno Osaka University
Title: Automorphisms of fine curve graphs for nonorientale surfaces
Abstract: The fine curve graph of a surface was introduced by Bowden, Hensel, andWebb as a graph consisting of the actual essential simple closed curves on the surface.
Long, Margalit, Pham, Verberne, and Yao proved that the automorphism group of thefine curve graph of a closed orientable surface is isomorphic to the homeomorphismgroup of the surface. We generalized their result to closed nonorientable surfaces Ngof genus g ≥ 4. This is a joint work with Mitsuaki Kimura.

Gye-Seon Lee Seoul National University
Title: Convex cocompactness for Coxeter groups
Abstract: There are several notions of convex cocompactness for discrete subgroupsof PGL(V ) acting on the projective space P (V ), where V is a finite-dimensional real29

vector space. This generalizes both the classical theory of convex cocompactness inreal hyperbolic geometry, and the theory of divisible convex sets. In this talk, I will
explain these notions in the context of Vinberg’s theory of discrete reflection groups.
Joint work with Jeﬀrey Danciger, François Guéritaud, Fanny Kassel and Ludovic
Marquis.

Jaewon Lee KAIST
Title: Obstructing 2-torsion in the rational concordance group
Abstract: It is well known that there are many 2-torsion elements in the concordancegroup. On the other hand, it is not known if there is any torsion element in the rational
concordance group CQ . Cha defined the algebraic rational concordance group AC Q ,an analogue of the classical algebraic concordance group, and showed that AC Q =∞Z∞ ⊕ Z∞
2 ⊕ Z4 . The knots that represent 2-torsion in AC Q potentially have order two
in CQ . In this talk, we provide an obstruction for algebraically rationally 2-torsion
knots from being of finite order in CQ . Moreover, we give a family consisting of suchknots that generates an infinite rank subgroup of CQ . We also remark that Cha proved
that, in higher dimensions, the algebraic rational concordance order is the same as therational concordance order. Our obstruction is based on the localized von Neumannρ-invariant.

Jung Hoon Lee Jeonbuk National University
Title: Primitive curve complex for a handlebody
Abstract: A simple closed curve C in the boundary Σ of a handlebody V is aprimitive curve if there exists a disk D in V such that C intersects ∂D transversely
in a single point. Such a disk D is called a dual disk of C, and (C, D) is called a dual
pair. Two primitive curves C and C ′ in Σ are said to be separated if there exist dual
disks D and D′ of C and C ′ respectively such that C ∪ D and C ′ ∪ D′ are disjoint.
We show that for any primitive curves C and C ′ in the boundary of a genus-g (≥ 2)
handlebody, there exists a sequence C = C1 , C2 , . . . , Cn = C ′ of primitive curves suchthat Ci and Ci+1 are separated for each i ∈ {1, 2, . . . , n − 1}. As a consequence, theprimitive curve complex and the separating disk complex of a genus-g handlebody areconnected for every g ≥ 2.

Fengchun Lei Dalian University of Technology
Title: On H ′ -splittings of handlebodies
Abstract: Let F be a compact connected orientable surface properly embedded30

in a compact connected orientable 3-manifold M . If F is separating M into two
handlebodies H1 and H2 , we say that H1 ∪F H2 is an H ′ -splitting of M . In the talk,we will describe a characteristic of an H ′ -splitting for a handlebody.

Fengling Li Dalian University of Technology
Title: New polynomial invariants for knotoids
Abstract: As a generalization of the classical knots, knotoids deal with the open
ended knot diagram in a surface. In recent years, many polynomial invariants for
knotoids appeared, such as the bracket polynomial, the index polynomial and the nthpolynomial, etc. In this talk, we will introduce a family of new polynomial invariants
for knotoids and discuss some properties of them. This is joint work with Yi Feng.

Youlin Li Shanghai Jiao Tong University
Title: Strongly exceptional Legendrian connected sum of two Hopf links
Abstract: A Legendrian link in a contact 3-manifold is a smooth link that is tangent
to the contact structure at every point. In an overtwisted contact 3-manifold, a
Legendrian link is called “exceptional” if its complement is tight. It is considered“strongly exceptional” if its complement is tight and does not have Giroux torsion.
In this talk, the strongly exceptional Legendrian representatives of connected sum of
two Hopf links in contact 3-spheres are completely classified. This is joint work with
Sinem Onaran.

Jiming Ma Fudan University
Title: Complex hyperbolic quadrangle groups
Abstract: We study representations of hyperbolic quadrangle groups into the isometric group of the complex hyperbolic plane. We show the discreteness and faithfulnessof a representation with double accidental parabolicities. In particular, the 4-cusped
hyperbolic 3-manifold S3 − L12n2205 admits a spherical CR uniformization, where
L12n2205 is the link in Hoste-Thistlethwaite’s table.

Langte Ma Shanghai Jiao Tong University
Title: Homology S 1 × S 3 and TQFT
Abstract: In this talk, I will survey recent developments on the study of gauge
theoretical invariants defined over closed smooth four manifolds whose integral homology is the same as that of S 1 × S 3 . The Seiberg–Witten type invariant defined by31

Mrowka–Ruberman–Salieve is proved to satisfy TQFT properties. Conjecturally, it isequivalent to the Yang–Mills type invariant introduced by Furuta–Ohta. The equivalence between these two invariants will lead to interesting consequences, including a
conjecture of Akbulut.

Ryo Matsuda Kyoto University
Title: Maximal cusps are not dense for the infinite-dimensional Teichmüller spaces
Abstract: It is known that the Bers boundary of a finite dimensional Teichmüller
space has only a cusp and totally degenerate. McMullen has also shown that the setof all maximal cusps is dense in the Bers boundary. In this talk, we first show thata new type of degenerate called the David-Fuchsian b group, exists when Riemannsurfaces satisfy the lower condition. The Riemann surface corresponding to this groupis homeomorphic to the base point of Teichmüller space. Using this result, I will provethat the maximal cusps are not dense if the Riemann surface has at least two nonplanar ends and satisfies the Shiga condition.

Naoyuki Monden Okayama University
Title: Ruled surfaces and indecomposable Lefschetz fibrations
Abstract: Ruled surfaces play an important role in the theory of Lefschetz fibrations.
In fact, Lefschetz fibrations on blow-ups of ruled surfaces have given many interesting
examples. In this talk, we give a relation among the genus of the base space of blowups of a ruled surface admitting a Lefschetz fibration, the number of blow-ups andthe genus of the Lefschetz fibration. Using this relation, we obtain a condition for
a Lefschetz fibration to be fiber sum indecomposable. Moreover, we give fiber sum
indecomposable Lefschetz fibrations on minimal total spaces.

Carl-Fredrik Nyberg-Brodda KIAS
Title: On the freeness problem for parabolic subgroups of SL(2, C)
Abstract: I will report on some recent results on the freeness problem for parabolic
subgroups of SL(2, C).

Makoto Ozawa Komazawa University
Title: Critical complexes for the 3-sphere
Abstract: A simplicial complex is said to be critical for the 3-sphere S 3 if it cannot
be embedded in S 3 but after removing any one point, it can be embedded.
32

We show that if a multibranched surface cannot be embedded in S 3 , it contains a
critical complex which is a union of a multibranched surface and a (possibly empty)
graph. We exhibit all critical complexes which are contained in K5 × S 1 and K3,3 × S 1
families. We also classify all critical complexes which have a form (G × S 1 ) ∪ H, where
G and H are graphs.
In spite of the above property, there exist complexes which cannot be embedded in3
S , but they do not contain any critical complexes. From the property of those examples, we define an equivalence relation on all simplicial complexes C and a partiallyordered set of complexes (C/ ∼; ⫅), and refine the definition of critical. According to
the refined definition of critical, we show that if a complex X cannot be embedded in
S 3 , then there exists [X ′ ] ⫅ [X] such that [X ′ ] is critical for [S 3 ].
This is a joint work with Mario Eudave-Muñoz.

Kyungbae Park Kangwon National University
Title: Alexander polynomial of twisted torus knots
Abstract: Twisted torus knots are a generalization of torus knots obtained by introducing additional full twists to adjacent strands of torus knots. In this talk, we
present an explicit formula for the Alexander polynomial of twisted torus knots. We
use a presentation of the knot group of twisted torus knots and Fox’s free diﬀerential
calculus. We further explore the applications of our computations, including a determination of the genus for certain families of twisted torus knots. This is joint workwith Adnan.

Andreani Petrou OIST
Title: Factorisation of the Harer-Zagier transform for HOMFLY-PT polynomials
Abstract: I will talk about the Laplace transform of the HOMFLY-PT polynomial
for knots, called the Harer-Zagier (HZ) transform, which is a function of two variables
λ and q. For some special families of knots it admits a fully factorised form. This
is not true, however, for the majority of knots, for which it can only be decomposed
as a sum of factorised terms. An interesting relation between this decomposition and
Khovanov homology will be discussed. Notwithstanding, we suggest that by fixing
the variable λ = q n , for some “magical” exponent n, the HZ transform of any knot
can obtain a factorised form in terms of cyclotomic polynomials. Moreover, I will talkabout the zeros of HZ transform which show an interesting behavior.

33

Toshio Saito Joetsu University of Education
Title: Exceptional or half-integral chirally cosmetic surgeries
Abstract: A pair of Dehn surgeries on a knot is called chirally cosmetic if theyyield orientation-reversingly homeomorphic 3-manifolds. In this talk, based on several
restrictions previously obtained, I will talk about exceptional or half-integral chirally
cosmetic surgeries. This is joint work with Kazuhiro Ichihara.

Kento Sakai Osaka University
Title: Degeneration of hyperbolic ideal polygons along harmonic map rays
Abstract: Let S be a surface of hyperbolic type and X be a complex structure on S.
If S is a closed surface, Wolf constructed a homeomorphism between the Teichmüller
space T (S) of S and the vector space of holomorphic quadratic diﬀerentials on X
via harmonic maps between surfaces. A ray in the vector space of the holomorphic
quadratic diﬀerentials determines the one-parameter family of hyperbolic surfaces
through that homeomorphism. The one-parameter family is called the harmonic map
ray. He also showed that a harmonic map ray converges to an R-tree in the sense ofequivariant Gromov-Hausdorﬀ convergence if taking a lift to the universal covering andproperly rescaling the hyperbolic metrics. In this talk, I will introduce the analogue
result in the case that S is a hyperbolic ideal polygon, which is based on Gupta’s
result about the coordinates of the Teichmüller spaces of hyperbolic surfaces withcrowns via harmonic maps. We consider a pointed Gromov-Hausdorﬀ convergence
instead of the equivariant version, since a hyperbolic ideal polygon does not have any
nontrivial action by the surface group.

Takuya Sakasai The University of Tokyo
Title: On groups of Kim-Manturov
Abstract: We consider some groups related to the group Γ4n defined by S. Kim and
V. O. Manturov. We discuss their structures (subgroups, generating sets and so on)
from the group theoretical point of view. This is a joint work with Kokoro Tanaka
and Yuuki Tadokoro.

Dounnu Sasaki Gakushuin University
Title: Counting subgroups via Mirzakhani’s curve counting
Abstract: Given a closed hyperbolic surface Σ of genus g, Mirzakhani proved thatthe number of closed geodesics of length at most L and of a given type is asymptotic
to cL6g−6 for some c > 0. Since a closed geodesic corresponds to a conjugacy class of34

the fundamental group π1 (Σ), we extend this to the counting problem of conjugacy
classes of finitely generated subgroups of π1 (Σ). Using ‘half the sum of the lengthsof the boundaries of the convex core of a subgroup’ instead of the length of a closed
geodesic, we find that the number of such conjugacy classes is similarly asymptotic to
cL6g−6 for some c > 0. Furthermore, we argue that this measurement for subgroups is‘natural’ within the framework of subset currents, which is a completion of weighted
conjugacy classes of finitely generated subgroups of π1 (Σ).

Mai Sato Tsuda University
Title: Equivalence classes of RotE2 -colorings of a diagram of a torus knot
Abstract: For each quandle X, it is well-known that there is a bijection between
the sets of X-colorings of two oriented knot diagrams which are related to each otherby a finite sequence of Reidemeister moves and planar isotopies. In this talk, we
introduce an equivalence relation, named R-equivalence, on the set of X-coloringsof an oriented knot diagram utilizing these bijections. We further determine the Requivalence classes of RotE2 -colorings, satisfying a certain condition, of a diagram ofa torus knot. Here, RotE2 is a quandle consisting of the rotational transformationsof the Euclidean plane E2 .

Xiaobing Sheng Okinawa Institute of Science and Technology
Title: Some experimental results of knots and links constructed from Thompson’sgroup F a la Jones
Abstract: Vaughan Jones, in his late years, motivated by an attempt to develop new
conformal field theory, obtained unitary representations of Thompson’s groups F and
T and these results further stimulated researches on Jones construction, from boththe aspect of pure maths and mathematical physics.
As one of the consequences, Jones found a rather concrete way of constructing
knots and links from Thompson’s group F as an analogue of results on braid groups.
Aiello and Baader extended these results to the positive oriented Thompson’s group−→
F which is isomorphic to Higman (Brown-) Thompson group F3 .
In this talk, I would like to present a sequence of computational results on certain
sequences of knots and links constructed from certain sequences of words in F and we
also provide a way of estimating the number of crossings from some group theoretic
property.

35

Tatsumasa Suzuki Tokyo Institute of Technology
Title: The d-invariants of Brieskorn homology 3-spheres with almost simple linear
graphsAbstract: In 2003, Ozsváth and Szabó introduced an invariant of rational homology
spinc cobordisms called a d-invariant. In 2020, Karakurt and Şavk investigated the dinvariant of any Brieskorn homology 3-sphere Σ(p, q, r) with pq + pr − qr = 1. These
homology 3-spheres have surgery diagrams that can be regarded as almost simple
linear graphs. They derived concrete calculation results with p even and a formulawith p odd. In this talk, we find a sharper evaluation formula when p is odd andpresent some suﬃcient conditions for the equality of this formula.

Natsuya Takahashi Osaka University
Title: Exotic 4-manifolds with small trisection genus
Abstract: A trisection genus is an integer-valued invariant of smooth 4-manifolds,
which can be considered as a 4-dimensional analogue of Heegaard genus for 3-manifolds.
Lambert-Cole and Meier conjectured that any exotic pair of 4-manifolds has the same
trisection genus. In this talk, we will give an exotic pair of 4-manifolds with boundarythat satisfies the conjecture. The trisection genus of our exotic pair is 4, which is thesmallest value known to date.

Akihiro Takano The University of Tokyo
Title: The p-colorable subgroup of Thompson’s group F
Abstract: Recently, Jones introduced a method of constructing knots and links
from elements of Thompson’s group F by using its unitary representations. He also
defined a subgroup of F as the stabilizer subgroup, called the 3-colorable subgroup.
We proved that all knots and links obtained from non-trivial elements of this groupare 3-colorable. In this talk, we extend this result to any odd integer p greater than
two. Namely, we define the p-colorable subgroup of F whose non-trivial elements yield
p-colorable knots and links, and show that it is isomorphic to the Brown–Thompson
group. This is joint work with Yuya Kodama (Tokyo Metropolitan University).

Kokoro Tanaka Tokyo Gakugei University
Title: The second quandle homology group of the knot n-quandle
Abstract: The knot quandle is known to be a complete invariant for oriented classicalknots up to orientation. Eisermann computed the second quandle homology groupof the knot quandle and showed that it characterizes the unknot. In this talk, we
36

compute the second quandle homology group of the knot n-quandle for each integern > 1, where the knot n-quandle is a certain quotient of the knot quandle. Although
the knot n-quandle is weaker than the knot quandle, the second homology group of
the former is found to have more information than that of the latter. As one of
the consequences, it follows that the second quandle homology group of the knot 3quandle characterizes the unknot, the trefoil and the cinquefoil. This is a joint workwith Yuta Taniguchi (Osaka University).

Motoo Tange University of Tsukuba
Title: Lens space surgeries on homology spheres of λ = −2, −3
Abstract: Berge listed lens space surgeries on S 3 in terms of doubly primitive construction in the 1990’s. In 2009, Tange listed lens space surgeries on Σ(2, 3, 5) by
the same method. By Greene and Caudell it is proven that these examples are alllens spaces obtained from S 3 or Σ(2, 3, 5). In this talk, we will list lens space surgeries Kp = L(p, q) on homology spheres with the Casson invariants −2 or −3 up top ≤ 1200 by using doubly primitive construction. We conjecture that this list gives
all lens spaces obtained from such homology spheres. This is a joint work with Tauchi
Koichi.

Sohei Tateno Nagoya University
Title: On the Iwasawa-type formula for Zdp -covers of links
Abstract: It is known that there are deep analogies between algebraic number theory
and low dimensional topology. Hillman-Matei-Morishita, Kadokami-Mizusawa, andUeki proved analogous theorems for links corresponding to Iwasawa’s class number formula. In this talk, as Cuoco-Monsky generalized Iwasawa’s formula to Zdp -extensions,
we will give asymptotic formulae for the first homology groups of Zdp -covers of links.
We will also describe the relationship between the characteristic element of the Zcp cover of a c-component link and those of Zdp -subcovers of the link. This is a joint workwith Jun Ueki.

Jun Ueki Ochanomizu University
Title: Profinite rigidity of the multivariable Alexander polynomials of links
Abstract: The multivariable Alexander polynomial of a d-component link in S 3 isdetermined by the isomorphism class of the link group up to GLn Z-action on thevariables. We study to what extent the polynomial is determined by the isomorphism

37

class of the profinite completion of the link group. This talk is based on a joint workwith Biao Ma at Technion.

Yohei Wakamaki Osaka University
Title: Stabilizations of some small exotic rational surfaces
Abstract: A 4-manifold is called almost completely decomposable (ACD) if it becomes diﬀeomorphic to kCP2 #lCP2 for some integers k, l ≥ 0 after taking a connected sum with CP2 . Although there are infinitely many examples of exotic 4manifolds that are confirmed to be ACD, those with second Betti numbers less than 10
are relatively rare. In this talk, we show that an example of an exotic rational surface
with the second Betti number b2 = 7, 8, 9, and 10 (i.e., an exotic CP2 #(b2 −1)CP2 ) isACD. In particular, among known ACD exotic 4-manifolds with explicitly given Kirby
diagrams, the above exotic CP2 #6CP2 is the smallest in terms of the second Betti
number. If time permits, we also discuss a similar result that an exotic CP2 #5CP2
becomes diﬀeomorphic to 2CP2 #6CP2 after taking a connected sum with S 2 × S 2 .

Junhua Wang Jiangsu University of Technology
Title: Small diﬀerence between tunnel numbers of cable knots and their companions
Abstract: In this talk, we will give a suﬃcient and necessary condition which iscalled p/q-primitive for when the tunnel number of a p/q-cable knot equals to that ofits companion. This is a joint work with Wenjie Diao and Yanqing Zou.

Zhongzi Wang Peking University
Title: Extendability over the 4-sphere and invariant spin structures of surface automorphisms
Abstract: I will talk about recent development on the topic indicated by the title.
The talk is based on joint papers with Shicheng Wang and with Weibiao Wang.

Zixi Wang Zhejiang Normal University
Title:Profinite rigidity and flexibility of some branched twisted spin 2-knots
Abstract: It has been recently focused that whether some given manifold could be
distinguished by the collection of its finite covers, i.e. by the profinite completion of
its fundamental group. We care about one class of 4-dimensional manifolds which arecomplement of branched spin 2-knots and give some results about the condition forthem to be profinitely rigid or flexible.
38

Xiaolei Wu Fudan University
Title: Compactly-supported classes in the homology of big mapping class groups
Abstract: I will start the talk with an overview about the theory of big mapping classgroups. Then I will discuss some recent advances on the homology of big mappingclass groups. In particular, I want to talk about some of recent work with Martin
Palmer on when a homology class of the big mapping class groups could have compact
support.

Kouki Yamaguchi Kyoto University
Title: On the 3-loop polynomial of genus 1 knots with trivial Alexander polynomial
Abstract: The Kontsevich invariant of knots is an universal invariant among all
quantum invariants and all Vassiliev invariants. The Kontsevich invariant is expandedin the special form which is called the loop expansion, and its 3-loop part is presented
by the 3-loop polynomial (3-loop invariant). In this talk, we give a restriction of theset of possible values of the 3-loop polynomials of genus 1 knots with trivial Alexanderpolynomial. As a special case, we present the 3-loop polynomial of any genus 1 knot
with trivial (≤ 2)-loop polynomials by using five Vassiliev invariants of the knot.
Further, we give a new example of the calculation of the 3-loop polynomial.

Wenyuan Yang Peking University
Title: Limit sets for branching random walks on relatively hyperbolic groups
Abstract: Branching random walks (BRW) on groups consist of two independent
processes on the Cayley graphs: branching and movement. Start with a particle
on a favorite location of the graph. According to a given oﬀspring distribution, theparticles at the time n split into a random set of particles with mean r ≥ 1, each ofwhich then moves independently with a fixed step distribution to the next locations.
It is well-known that if the oﬀspring mean r is less than the spectral radius of theunderlying random walk, then BRW is transient: the particles are eventually free on
any finite set of locations. The particles trace a random subgraph which accumulates
to a random subset called limit set in a boundary of the graph. In this talk, we
consider BRW on relatively hyperbolic groups and study the limit set of the trace at
the Bowditch and Floyd boundaries. In particular, the Hausdorﬀ dimension of thelimit set will be computed. This is based on a joint work with Mathieu Dussaule andLongmin Wang.

39

Xiliu Yang Peking University
Title: Knot Floer homology and the fundamental group of (1,1) knots
Abstract: Knot Floer homology is a categorification of the Alexander polynomialof knots introduced independently by Ozsvath and Szabo and by Rasmussen. The
explicit relationship between the fundamental group and the knot Floer homology is
one of the fundamental questions about Heegaard Floer homology raised by Ozsvathand Szabo. In this talk, I will explain our recent progress on this question for (1,1)
knots. We give an algorithm for computing the knot Floer homology of a (1,1) knot
from a particular presentation of its fundamental group. This is joint work with Jiajun
Wang.

Jumpei Yasuda Osaka University
Title: Alexander theorem on surfaces in the 4-ball using knitted surfaces
Abstract: Knits (or BMW-tangles) are tangles in a cylinder obtained from braids bysplicing for some crossings. In this talk, we generalize knits for surface-knot theory as
knitted surfaces (or BMW surfaces). These surfaces are properly embedded surfaces
in the 4-ball with non-empty boundaries. We show that every properly embedded
surface in the 4-ball with a non-empty boundary is ambiently isotopic to a knitted
surface. This is joint work with Inasa Nakamura (Saga University).

Leo Yoshioka The University of Tokyo
Title: Non-trivial cycles of the spaces of long embeddings detected by 2-loop graphs
Abstract: In this talk, we introduce machinery to give geometric and non-trivial(co)cycles of the spaces of long embeddings. We construct these cocycles by integral over configuration spaces associated with 2-loop graphs. This framework is a
generalization of several works for 1-loop graphs by Bott, Cattaneo, Rossi, Sakai and
Watanabe. Using 2-loop graphs, we obtain higher-degree cocycles of long embeddings,
even with codimension two. The non-triviality of the cocycles is shown by counting
graphs on some diagrams. If time permits, we compare our 2-loop graphs with hairygraphs, which Arone and Turchin introduced in embedding calculus.

Bin Yu Tongji University
Title: Self orbit equivalences on a class of Anosov flows
Abstract: Let Mk (k ∈ Z and |k| > 4) be the 3-manifold obtained by doing k Dehn
surgery on the figure-eight knot, and Xt be the canonical Anosov flow on Mk that isconstructed by Goodman. In this talk, I will explain a brief proof of the following
40

result: if |k| ≫ 0, then M od(Mk ) ∼= Z4 and every element of the mapping class groupof Mk can be represented by a self orbit equivalence of Xt . This answered a question
asked by Barthelme and Mann.

Ying Zhang Soochow University
Title: Length minima for an infinite family of filling closed curves on a one-holed
torus
Abstract: We explicitly find the minima as well as the minimum points of thegeodesic length functions for the family of filling (hence non-simple) closed curves,a2 bn (n ≥ 3), on a complete one-holed hyperbolic torus in its relative Teichmüller
space, where a, b are simple closed curves on the one-holed torus which intersect exactly once transversely. This provides concrete examples for the problem to minimize
the geodesic length of a fixed filling closed curve on a complete hyperbolic surface offinite type in its relative Teichmüller space. This is joint work with Zhongzi Wang.

Yanqing Zou Tongji University
Title: Some results of tunnel numbers of satellite knots
Abstract: We will show our recent results on tunnel numbers of satellite knots andtheir companions. This is a joint work with Wang Junhua, Diao Wenjie and Yan
Chunxing.

41

5. List of Participants

Katsunori Arai (Osaka University)

Wonyong Jang (KAIST)

Yongju Bae (Kyungpook National University)

Jinho Jeoung (Seoul National University)

Jean-Baptiste Bellynck (Osaka University)

Gyo Taek Jin (KAIST)Jae Choon Cha (POSTECH)

Hongtaek Jung (Seoul National University)

Wonjun Chang (POSTECH)

Teruhisa Kadokami (Kanazawa University)

Haimiao Chen (Beijing Technology and Business University)

Naoko Kamada (Nagoya City University)
Seiichi Kamada (Osaka University)

Zhechi Cheng (Wuhan University)

Sungkyung Kang (University of Oxford)

Zhiyun Cheng (Beijing Normal University)

Sungmo Kang (Chonnam National University)

Sangbum Cho (Hanyang Unversity)

Shunsuke Kano (Tohoku University)

Seonmi Choi (Kyungpook National University)

Hiroaki Karuo (Gakushuin University)

Ryoga Furutani (Hiroshima University)
Honghao Gao, (Tsinghua University)

Yasushi Kasahara (Kochi University of Technology)

Yue Gao (Anhui Normal University)

Mai Katada (Kyushu University)

Stavros Garoufalidis (Southern University of
Science and Technology)

Akishi Kato (The University of Tokyo)
Kengo Kawamura (Osaka Sangyo University)

Noriyuki Hamada (Kyushu University)

Byeorhi Kim (POSTECH)

Mikami Hirasawa (Nagoya Institute of Technology)

Junseok Kim (KAIST)

Kazuhiro Ichihara (Nihon University)

Min Hoon Kim (Kyungpook National University)

Shotaro Imachi (Kyoto University)

Minkyu Kim (KIAS)

Ayumu Inoue (Tsuda University)

Sang-hyun Kim (KIAS)

Kamolphat Intawong (National Institute ofTechnology, Ibaraki College)

Se-Goo Kim (Kyung Hee University)
Seungwon Kim (Sungkyunkwan University)

Ingrid Irmer (Southern University of Scienceand Technology)

Naoki Kimura (Waseda University)

Katsumi Ishikawa (RIMS, Kyoto University)

Eiko Kin (Osaka University)

Goo Ishikawa (Hokkaido University)

Unhou Kin (Nagoya City University)

Noboru Ito (National Institute of Technology,
Ibaraki College)

Takahiro Kitayama (University of Tokyo)

Tetsuya Ito (Kyoto University)

Ryoma Kobayashi (National Institute of Technology, Ishikawa College)

Kentaro Iwai (Kyoto University)

Yuya Koda (Keio University)42

Toshitake Kohno (Meiji University)

Makoto Ozawa (Komazawa University)

Jin Kosaka (Osaka University)

Kyungbae Park (Kangwon National University)

Andrew Kricker (Nanyang Technological University)

Andreani Petrou (Okinawa Institute of Scienceand Technology)

Hajime Kubota (Kyoto University)

Ruifeng Qiu (East China Normal University )Erika Kuno (Osaka University)

Toshio Saito (Joetsu University of Education)

Thang Le (Georgia Institute of Technology)

Kento Sakai (Osaka University)

Gye-Seon Lee (Seoul National University)

Takuya Sakasai (The University of Tokyo)

Jaewon Lee (KAIST)

Dounnu Sasaki (Gakushuin University)

Jung Hoon Lee (Jeonbuk National University)

Mai Sato (Tsuda University)

Fengchun Lei (Dalian Univerisity of Technology)

Shota Segawa (Osaka University)
Seung Yeop Yang (Kyungpook National University)

Fengling Li (Dalian Univerisity of Technology)

Xiaobing Sheng (Okinawa Institute of Scienceand Technology)

Ping Li (Fudan University)
Yanlin Li (Hangzhou Normal Unniversity)

Reiko Shinjo (Kokushikan University)
Youlin Li (Shanghai Jiao Tong University)
Masaaki Suzuki (Meiji University)
Yi Liu (Peking University)
Sakie Suzuki (Tokyo Institute of Technology)
Jiming Ma (Fudan University)
Langte Ma (Shanghai Jiao Tong University)

Tatsumasa Suzuki (Tokyo Institute of Technology)

Shuhei Maruyama (Kanazawa University)

Natsuya Takahashi (Osaka University)

Ryo Matsuda (Kyoto University)

Akihiro Takano (The University of Tokyo)

Yukio Matsumoto (Gakushuin University)

Kokoro Tanaka (Tokyo Gakugei University)

Ryosuke Miki (Osaka University)

Motoo Tange (University of Tsukuba)

Naoyuki Monden (Okayama University)

Yuta Taniguchi (Osaka University)

Gabriel Montoya-Vega (CUNY Graduate Center and University of Puerto Rico-Rio Piedras)

Sohei Tateno (Nagoya University)
Haruchika Tsuno (Osaka University)

Kimihiko Motegi (Nihon University)

Yudai Ueda (RIMS, Kyoto University)

Jun Murakami (Waseda University)

Jun Ueki (Ochanomizu University)

Inasa Nakamura (Saga University)

Yohei Wakamaki (Osaka University)

Takumi Nakashima (Kyoto University)

Jiajun Wang (Peking University)

Yuya Nishimura (Hiroshima University)
Carl-Fredrik Nyberg-Brodda (KIAS)

Junhua Wang (Jiangsu University of Technology)

Tomotada Ohtsuki (RIMS, Kyoto University)

Shicheng Wang, (Peking University)
43

Zhongzi Wang (Peking University)

Jumpei Yasuda (Osaka University)

Zixi Wang (Zhejiang Normal University)

Kouichi Yasui (Osaka University)

Tadayuki Watanabe (Kyoto University)

Leo Yoshioka (The University of Tokyo)

Xiaolei Wu (Fudan University)

Bin Yu (Tongji University)

Yuichi Yamada (The Univ. of Electro-Comm.)

Wataru Yuasa (Kyoto University)

Kouki Yamaguchi (RIMS, Kyoto University)

Tang Yuxuan (Waseda University)

Wenyuan Yang (Peking University)

Ying Zhang (Soochow University)

Xiliu Yang, (Peking University)

Zou, Yanqing (East China Normal University)

44