Geometric Group Theory in East Asia


Welcome to the the GGTea Webinar.

The webinar provides a platform for communication and collaboration among young researchers in geometric group theory. We meet weekly for a one-hour talk followed by half an hour of informal discussion and tea. The talks should be accessible to graduate students. All are welcome to join.

The seminar usually takes place on Fridays at 10am (China) / 11am (Korea, Japan) / 12pm (Aus EST) / 9pm Thursday (US ET), unless otherwise adjusted for the speaker. The talks will be hosted on Zoom. All are welcome to tune in.

Meeting ID: 982 4085 5770

Passcode: a space satisfying the thin triangle property is called a ??? space (10 letters lower case).

This week

December 17 10am China Time: Ivan Levcovitz

Title: Random BMW groups

Abstract: BMW (Burger-Mozes-Wise) groups are a class of groups that act geometrically on the product of two infinite, regular trees. For large enough trees, these groups admit the same coarse geometry (they are all pairwise quasi-isometric), yet they can be algebraically quite different. In fact, by a celebrated result of Burger-Mozes, these groups can even be virtually simple. In this talk, I will discuss a random model for generating BMW groups and how we use ideas from this model to solve counting problems related to these groups. This is joint work with Nir Lazarovich and Alex Margolis.

2021 Schedule

Date Speaker Title
Dec. 17 Ivan Levcovitz Random BMW groups
Dec. 10 Asaf Hadari Uniform recurrence in linear group
Dec. 3 Yvon Verberne The asymptotic dimension of big mapping class groups
Nov. 26 Xiaoming Du The torsion generating set of the extended mapping class groups
Nov. 19 Abdul Zalloum Hyperbolicity in mapping class groups and right-angled Artin groups
Nov. 12 Tarik Aougab Properties of random curves
Nov. 5 4pm Elia Fioravanti Automorphisms and splittings of special groups
Oct. 29 Motoko Kato Acylindrical hyperbolicity of some Artin-Tits groups
Oct. 22 Sahana Balasubramanya Actions of solvable groups on hyperbolic spaces
Oct. 15 Yu-Wei Fan Quasimorphisms on the automorphism groups of certain triangulated categories
Oct. 8 Mark Pengitore Coarse embeddings and homological filling functions
Sep. 24 Qing Liu Rigidity of the Morse boundary
Sep. 17 4pm Mark Hagen Real Cubings
Sep. 10 Tsukasa Ishibashi Sign stability of mapping classes on marked surfaces
June 25 Anne Thomas Fixed points for group actions on 2-dimensional buildings
June 18 Krishnendu Gongopadhyay Reversibility of Hermitian Isometries
June 11 Murray Elder Deciding plainness in PSPACE
June 4 (4pm) Edgar A. Bering IV An algorithm to decide if a free-by-cyclic group is a 3–manifold group
May 28 Tomohiro Fukaya Visual maps between coarsely convex spaces
May 14 Huiping Pan Local rigidity of the Teichmuller space in the Thurston metric
May 7 Kasra Rafi The sublinearly morse boundary
April 30 (4pm) Richard Webb Homeomorphisms of surfaces, rotation sets, and the fine curve graph
April 23 Dounnu Sasaki Currents on cusped hyperbolic surfaces and denseness property
April 16 Masato Mimura The Green-Tao theorem for number fields
April 9 Yi Liu Finite-volume hyperbolic 3-manifolds are almost determined by their finite quotient groups
April 2 Thomas Ng Automorphism groups of one-ended groups that satisfy a uniform exponential growth subgroup alternative
Mar. 26 (4pm) Valentina Disarlo The model theory of the curve graph
Mar. 19 Derrick Wigglesworth The Farrell-Jones Conjecture for (most) hyperbolic-by-cyclic groups
Mar. 12 Ingrid Irmer A topology on mapping class groups
Feb. 26 Camille Horbez (4pm Beijing Time) Measure equivalence rigidity of Out(Fn)
Jan. 15 Kim Ruane Boundary rigidity of groups acting on a product of two trees
Jan. 8 Xiangdong Xie Groups whose left invariant metrics are roughly similar

2020 Schedule

Dec. 18 Ryokichi Tanaka Topological flows for hyperbolic groups
Dec. 11 Giulio Tiozzo (4pm Beijing Time) The fundamental inequality for hyperelliptic Fuchsian groups
Dec. 4 Hung C. Tran Divergence of finitely presented groups
Nov. 27 Rémi Coulon (3pm Beijing Time) Automorphisms with exotic growth
Nov. 20 Jing Tao Polygons, Horogons, and the Nielsen-Thurston Classification Theorem
Nov. 13 Yvon Verberne Strong contractability of geodesics in the mapping class group
Nov. 6 Tomoshige Yukita Continuity of the growth rate on the space of Coxeter groups
Oct. 30 🍁 Fall Social Lightning talks and open problems (program)
Oct. 23 Wenyuan Yang Croke-Kleiner admissible groups: Property (QT) and quasiconvexity
Oct. 16 Hoang Nguyen Quasiconvexity in 3-manifold groups
Oct. 9 Yulan Qing Introduction to big mapping class groups
Sep. 25 Hidetoshi Masai Continuity of the drift of mapping class group
Sep. 18 Hyungryul Baik Some problems in low-dimensional topology with dynamic nature
Sep. 11 Koji Fujiwara The rates of growth in a hyperbolic group.(slides)

Organizers: Hyungryul Baik (KAIST), Ingrid Irmer(SUSTech), Sang-Hyun Kim (KIAS/KAIST), Hidetoshi Masai (Tokyo Tech), Yulan Qing (Fudan), Robert Tang (XJTLU), Wenyuan Yang (Peking).

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