Welcome to the 2nd 3J Topology Seminar
The 2nd 3J Topology Seminar will be held at 北京中科院数学与系统科学研究院 from Dec. 20-22, 2019 (the 3rd weekend of December), hosted by AMSS (数学与系统科学研究院).
The seminar will be paperless. All the information about the seminar, including Talk Schedule, Abstracts of the talks, Travel Information, Accommodation and Dining arrangement, and Reimbursement Information, will be released at this page.
Message Board
- 12月18日： 活动信息已经完整更新了，诸位周末见！
Program
(Homotopy theory and its applications）
| Dec. 20, Friday | Dec. 21, Saturday | Dec. 22, Sunday | |
|---|---|---|---|
| 7:00 - 8:45 | Breakfast | Breakfast | |
| 8:45 - 9:00 | Opening | ||
| Chair | |||
| 9:00 - 09:50 | Jie Wu | Yang Su | |
| 9:50 - 10:20 | Tea Break | Tea Break | |
| 10:20 - 11:10 | Full-day Registration | Jie Wu | Huijun Yang |
| 11:10-11:40 | Tea Break | Tea Break | |
| 11:40-12:30 | Ye Liu | Sang Xie | |
| 12:30-14:30 | Lunch | Lunch | |
| 14:30-15:20 | Ye Liu | Free discussion/Leave | |
| 15:20-15:40 | Full-day Free discussion | Tea Break | |
| 15:40-16:10 | Yubo Liu | ||
| 16:10- | Free discussion | ||
| 18:00 | Dinner | Dinner |
- All talks will take place in (数学院南楼N219；从正门坐电梯至2楼，出来左手前方多媒体教室即是)
Talks
- Jie Wu (HNU) Slides
Title: $\mathrm{EHP}$ sequences, exponents of homotopy groups and the Barratt conjecture
Abstract: This is an introductory talk on the Barratt conjecture. The lecture will start from classical $EHP$ sequences. Then we move to talk about some recent research on generalized $EHP$ fibrations as well as some open questions on spherical fibrations over spheres. After showing that the $2$-torsion component of $\pi_*(S^3)$ has an exponent of $4$ as an introductory example, we highlight some classical results on the exponents of homotopy groups. Finally we will talk the Barratt Conjecture, which is a longstanding open problem, as well as the proposed approaches for attacking the conjecture.
- Ye Liu (XJTLU) Summary
Title: Topics on hyperplane arrangements
Abstract: In these talks, we survey the theory of hyperplane arrangements and its variants. Our goal is to give an introduction to some open problems in this field, especially those related to topology.
- Yubo Liu (CAS)
Title: On the Covering Type
Abstract: The covering type of a space X is a numerical homotopy invariant, which in some sense measures the homotopical size of X. In this talk，I’ll give a brief introduction of covering type.
- Yang Su (CAS)
Title: Finiteness and infiniteness of the Torelli groups of (hyper)-Kahler manifolds (2)
Abstract: The Torelli group of a closed smooth manifold X is the subgroup of the mapping class group consisting of elements which act trivially on the integral cohomology of X. In this note we give counterexamples to a theorem by Verbitsky which states that the Torelli group of simply connected Kahler manifolds of complex dimension >2 is finite. We also give a counterexample to the theorem of Verbitsky which claims that the Torelli group of hyper-Kahler manifolds are finite. Finally we confirm the finiteness result for the special case of the hyper-Kahler manifold K[2]. This is a joint work with M.Kreck.
- Huijun Yang (HU)
Title: Existence of contact structures on 9-manifolds
Abstract: In this talk, the necessary and sufficient conditions for a closed orientable 9-manifold to admit a contact structure will be given. In addition, seems to be of independent interest, we will prove that the 7-th integral Stiefel-Whitney class of a 9-dimensional spinc manifold is zero. This is a joint work with Diarmuid Crowley.
- Sang Xie (Nankai)
Title: SOME NOTES ON REALIZING SPACES AS CLASSIFYING SPACES
Abstract: The Dold-Lashof classifying space, $Baut_1 (X)$, is the classifying space for fibrations with fibre the homotopy type of $X$. There is a long-standing, open question in rational homotopy theory: Which simply connected rational homotopy types occur as $Baut_1(X)$? In this present, we will show the following unrealization result: The rational homotopy type of $CP^3$ is not realized as the classifying space of any simply connected, π-finite, rational space.
Travel Information
地址: 中国科学院数学与系统科学研究院南楼
北京市海淀区中关村东路55号
100190
乘车路线：这个家伙很懒，什么都没有留下！
(If you use Baidu or Gaode map, you do not need this)
Accommodation
- 我们已经为所有注册参会者预定了住宿；老师们都统一安排在辽宁大厦；学生们都统一安排在物科宾馆，两人一间。
- You do not need to pay the accommodation fees if you have applied the financial support from the host.
- Lunch at Saturday and Sunday are provided at 物科4楼（自助餐）
- Dinner at Friday and Saturday is provided at 物科3楼（桌餐）
Reimbursement Information
To apply reimbursement from the host, please contact Professor Yang Su (苏阳老师，suyang@math.ac.cn) with the following:
- 来回火车票
Mailing Address:
北京海淀区中关村东路55号
中国科学院数学与系统科学研究院 晨兴数学中心
苏阳