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[External Email] Dear geometers, First, I’d like to apologize to those who get this message on multiple lists, and also apologize that I’m sending this two days after the other announcements. I’d like to invite any interested parties to join me for the continuation of a lecture series I started at MIT in February, where I am currently visiting (sort of, in the present circumstances). This was not an official class, and because of my professional travel and then current events, there have only been three lectures so far. So I am able to open it up to the community at large. A description of the perspective and topics are below. The lectures will be at noon, Eastern Time, on Mondays starting on the 30th. For those who haven’t attended so far there will be a one-time optional “catch up” lecture at 11am Eastern Time on the 30th. Folks can also take a look at the accessible expository paper https://arxiv.org/abs/math/0610236<https://urldefense.com/v3/__https://arxiv.org/abs/math/0610236__;!!C5qS4YX3!QSQorDY5Fniima--UWLCm8WHh7X_oacJhLpI8QnmauFtklYTYyAUho5l7VnOnSk$>, which was the topic of lecture 2. E-mail me and I will add you to an e-mail list through which every Monday morning, starting this coming Monday, I will send out links for the lecture. (I will try to keep the links the same so they can be re-used, but since I will only be using freely available tools I make no promises.) Also, feel free to pass this invitation along. Best wishes, Dev Algebraic Topology from a Geometric Viewpoint Mondays at noon, re-starting March 30. (With one additional cial “catch up” lecture March 30 at 11) The level will be aimed at graduate students, not only in algebraic topology but in geometric topology as well as algebraic or differential or symplectic geometry, as well as anyone else interested in a geometric take on “intermediate” topics in algebraic topology. I will only assume basic algebraic topology (a year long course) and some basic differential topology (a subset of what is in the book by Guillemin-Pollack). The topics I plan to treat in such a manner are as follows. * (Catch-up lecture) Homology and cohomology of configurations in Euclidean space - these give rise to some fun combinatorics, and govern the homology of spaces of maps from spheres. * Homotopy periods / Hopf invariants - up to torsion all maps from spheres to a simply connected space are determined by “higher linking invariants, with correction.” The representatives in de Rham theory agree with integrals arising in field theory. This also gives rise to a new approach to the lower central series of groups, currently being written up (which has planned applications ranging from non-simply connected rational homotopy theory to the Johnson filtration). * Homology and cohomology of infinite Grassmannians - revisiting this standard calculation. * The geometry of Eilenberg-MacLane spaces, and their homology and cohomology. * Homology and cohomology of unordered configuration spaces - in particular, cohomology of symmetric groups. * The Blakers-Massey Theorem, and its application to configuration space models for spaces of embeddings, and resulting knot and link invariants. * Geometry of Steenrod operations, and progress towards E_\infty models for cochains on manifolds through intersection and linking.