"Topology and Probability, in the service of the most humungous data set of all"
Thursday May 23, 2019 — 6 PM @ The Barn (Ryerson 352)
Abstract. There are data sets that are normal sized, data sets that are large, and there are those that qualify as “Big Data”. And then there are the humungous ones, the humungousest of which is The Universe; i.e. cosmological data. Cosmological data sets are so overwhelming that, if you look hard enough, you can find almost anything that you want (or do not want) to find in them, and this calls for the development of powerful techniques that, on the one hand, summarize the data in a meaningful way and, on the other hand, allow for distinguishing between important physical phenomena and those which `you just happened to see by chance’. Abstract mathematical concepts from the rather esoteric area of Algebraic Topology provide a set of techniques, for the first of these problems, while Probability Theory provides the second set. I will explain how all all three of these topics - Cosmology, Algebraic Topology, and Probability Theory - fit together, although I will not assume any prior knowledge of any of them. (i.e. Lots of pictures, hardly any formulae, and definitely not even an attempt at a proof (despite the fact that a lot of the fun is in the proofs).