Fall 2026:
10/26/26: TBD.
09/28/26: Audrick Pyronneau: Hillman-Kasprowski-Powell-Ray: Homotopy classification of 4-manifolds with 3-manifold fundamental group.
09/21/26: Maggie Miller: Hughes-Kim-Miller-Nahm: An irreducible real projective plane in the 4-sphere.
09/14/26: Daniel Galvin: Kervaire: A manifold which does not admit any differentiable structure.
08/31/26: Anthony Conway: Hambleton-Kreck-Teichner: Topological 4-manifolds with geometrically 2-dimensional fundamental groups.
Spring 2026
04/27/26: Daniel Galvin: Burghelea-Lashof: The homotopy type of the space of diffeomorphisms.
04/20/26: Anthony Conway: Introduction to the odd surgery monoid, following Section 6 of Kreck: surgery and duality and Crowley-Sixt: Stably diffeomorphic manifolds and l_{2q+1}(Z[pi]) .
04/13/26: Simona Vesela (MPIM): On characteristic classes in the topological category.
04/06/26: Ansel Goh: Kasproswki-Powell: Stably exotic 4-manifolds.
03/30/26: Audrick Pyronneau: Spin unions of surface exteriors.
03/23/26: Anthony Conway: Hillman-Kasprowski-Powell-Ray: Homotopy classification of 4-manifolds with 3-manifold fundamental group.
03/09/26: Ansel Goh: Kreck-Su: On 5-manifolds with free fundamental group and simple boundary links in S^5.
03/02/26: Audrick Pyronneau: Powell: Spanning 3-discs in the 4-sphere pushed into the 5-disc.
02/23/26: Slava Krushkal (University of Virginia): Pseudo-isotopies of non-simply connected 4-manifolds.
02/16/26: Anthony Conway: The AB-slice problem, following the DET book (Chapter 23) and Freedman: Are the borromeans AB-slice?
02/02/26: Daniel Galvin: Obstructions in the controlled h-cobordism theorem, following Freedman-Quinn's The topology of 4-manifolds (Theorem 7.2A) and Quinn: Ends of maps II.
01/29/26: Anthony Conway: Good groups, Outline that elementary amenable groups are good, following the DET book (Chapter 19).
01/12/26: Anthony Conway: Good groups, Definition and first properties, following the DET book (Chapter 19).
Fall 2025
12/08/25: Anthony Conway: Wilczynski: On the topological classification of pseudofree group actions on 4-manifolds I.
12/01/25: Anthony Conway: Wilczynski: On the topological classification of pseudofree group actions on 4-manifolds I.
11/17/25: Nathan Louie: Cha-Kim: Lightbulb smoothing for topological surfaces in 4-manifolds (Theorem C).
11/10/25: Audrick Pyronneau: Classifying closed, spin, simply-connected 4-manifolds via the normal 2-type, II
11/03/25: Ansel Goh: Classifying closed, spin, simply-connected 4-manifolds via the normal 2-type, I
10/27/25: Daniel Galvin: On the connectedness of the map Top(4)/O(4) -> Top/O; related to Quinn: Ends of maps III, Corollary 2.2.3.
10/20/25: Ansel Goh: Hambleton-Kreck: Homotopy self-equivalences of 4-manifolds (Theorem B).
10/13/25: Anthony Conway: Knot concordance and intro to homology surgery.
10/06/25: Anthony Conway. Kwasik: On the symmetries of fake CP2.
09/29/25. Audrick Pyronneau. Boyer: Realisation of 4-manifolds with a given boundary (Theorem F).
09/22/25. Daniel Galvin. On the group TOP and the homotopy groups of TOP/O.
09/15/25. Remy Bohm. McCooey: Concordance of Z_pxZ_p actions on S^4.
09/08/25. Anthony Conway. Cha-Kim-Powell: A family of freely slice good boundary links.
08/25/25. Anthony Conway. A short introduction to the surgery conjecture.
Spring 2025
04/21/25. Lisa Piccirillo. Lidman-Piccirillo: Stably irreducible non-orientable knotted surfaces.
04/14/25. Audrick Pyronneau. Kreck: Isotopy classes of diffeomorphisms of (k-1)-connected almost-parallelizable 2k-manifolds.
04/07/25. Daniel Galvin (MPIM). Galvin-Nonino: Pseudo-isotopy versus isotopy for homeomorphisms of 4-manifolds.
03/31/25. John Teague. Kasprowski-Land-Powell-Teichner: Stable classification of 4-manifolds with 3-manifold fundamental groups.
03/24/25. Anthony Conway. Recap of classical and modified surgery; application to closed, spin, simply-connected 4-manifolds,
03/10/25. Jemma Schroder. Kasprowski-Land-Powell-Teichner: Stable classification of 4-manifolds with 3-manifold fundamental groups.
02/24/25. Anthony Conway. Orson-Powell: Simple spines of homotopy 2-spheres are unique.
02/17/25. Audrick Pyronneau. Orson-Powell: Simple spines of homotopy 2-spheres are unique.
02/10/25. Ansel Goh. On Whitehead torsion.
02/03/25. Anthony Conway. Intro to modified surgery theory, i.e. Kreck: Surgery and duality.
01/27/25. Anthony Conway. Davis-Hillman: Aspherical 4-manifolds with elementary amenable fundamental group.
Fall 2024
12/09/24: Anthony Conway. Hillman: Homotopy types of 4-manifolds with 3-manifold fundamental groups.
12/01/24: Mark Pencovitch. Feller-Miller-Nagel-Orson-Powell-Ray: Embedding spheres in knot traces.
11/18/24. Anthony Conway. Intro to surgery theory + Friedl-Teichner: New topologically slice knots.
11/ 13/24. Mark Powell (U. Glasgow). The 31-authored paper: Algorithms in 4-manifold topology.
11/04/24. Audrick Pyronneau. Kasprowski-Powell-Ray: Gluck twists on concordant or homotopic spheres.
10/28/24. Daniel Kasprowski (U. Southampton). Kasprowski-Teichner: CP2 -stable classification of 4 -manifolds with finite fundamental group.
10/21/24. Mark Pencovitch. Orson-Powell: Mapping class groups of simply connected 4-manifolds with boundary.
10/14/24. Anthony Conway. Boyer: Simply-connected 4-manifolds with a given boundary + Realisation of 4-manifolds with a given boundary.