Reading seminar: Freedman's proof of the 4-dimensional Poincaré conjecture

Wintersemester 2021/2022

Wednesdays, 13:15, seminar room 1.315



Content: The goal of this reading seminar is to understand Freedman's proof of the 4-dimensional Poincaré conjecture.
We will read every week a chapter from [BKKPR] and discuss the content in the Wednesdays slots.



Topics:
03.11.21 Smale's proof of the Poincaré conjecture in higher dimensions
10.11.21 Context for the disc embedding theorem [BKKPR, Chapter 1]
17.11.21 Outline of the upcoming proof [BKKPR, Chapter 2]
24.11.21 Intersection numbers and the statement of the disc embedding theorem [BKKPR, Chapter 11]
01.12.21 Gropes, ... [BKKPR, Chapter 12]
08.12.21 ... towers, ... [BKKPR, Chapter 12]
15.12.21 ... and skyscrapers [BKKPR, Chapter 12]
05.01.22 Picture camp [BKKPR, Chapter 13]
12.01.22 Architecture of infinite towers and skyscrapers [BKKPR, Chapter 14]
19.01.22 Basic geometric constructions [BKKPR, Chapter 15]
26.01.22 From immersed discs to capped gropes I [BKKPR, Chapter 16]
02.02.22 no seminar
09.02.22 From immersed discs to capped gropes II [BKKPR, Chapter 16]


Literature:
[BKKPR] S. Behrens, B. Kalmár, M. Kim, M. Powell, and A. Ray, The disc embedding theorem, Oxford university press, 2021. Via your HU account it is available here.
[S] A. Scorpan, The wild world of 4-manifolds, AMS, 2005.