2021-11-24

Speaker: Zhifei Zhu

Title: Hopf invariant

We look at an example of application of Steenrod operations in Hopf invariants.

2021-11-17

Speakers: Nanjun Yang

Title: Construction of Steenrod operations III

This is a continuation of the previous seminar. In particular, we will talk about properties of Steenrod operations and Adem's relations. 

2021-11-10

Speakers: Nanjun Yang

Title: Construction of Steenrod operations II

This is a continuation of the previous seminar. In particular, we will talk about properties of Steenrod operations. 

2021-11-03

Speakers: Nanjun Yang

Title: Construction of Steenrod operations I

In this talk, we will define Steenrod operations and prove some basic properties of these operations.

The main reference will be the Section 4.L in A. Hatcher's book Algebraic Topology.

2021-10-27

Speakers: Zhifei Zhu

Title: Cohomology operations

This week we will finish the proof of the classification theorem of cohomology operations.

2021-10-20

Speakers: Zhifei Zhu

Title: Cohomology operations

We will discuss some basic notion of cohomology operations. In particular, we will discuss the classification of all cohomology operations, which give us some intuition of the Steenrrod squares.

The main reference is the first chapter of the book "Cohomology operations and applications in homotopy theory".

2021-9-22

Speakers: Zhifei Zhu

Title: Organizational Meeting 

We are hosting a learning seminar about min-max theory and cohomology operations in this semester.

Our plan is to go through the first five chapters of the book "Cohomology operations and applications in homotopy theory" by R. E. Mosher and M. C. Tangora, and the paper "Minmax problems related to cup powers and Steenrod squares" by L. Guth and many other related materials based on the interest of the audience.

We are also planning to invite some external speakers in December. If you wish to give a talk in this seminar, please feel free to contact me via zhifeizhu@mail.tsinghua.edu.cn. Currently, the learning seminar will be in person only. We will update if there are any online talks.