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# Tag Archives: topology

## London Combinatorics Colloquia 2019

In London last week for the two combinatorics colloquia, at Queen Mary and LSE. The weather was unusually grey and rainy; it seems in retrospect that it is almost always fine and sunny for this event, but I know that … Continue reading

Posted in events, exposition
Tagged 1-factorisations, Hadamard matrices, model theory, Ramsey theory, Regularity Lemma, Schur's theorem, stability, topology
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## Kinks?

I’ve just been at a conference called “Kinks 2”, or that might be “knkx 2” (I never saw it written down). But look at the list of topics: dynamics, functional equations, infinite combinatorics and probability. How could I resist that? … Continue reading

Posted in events
Tagged Adam Ostaszewski, dynamics, functional equations, infinite combinatorics, probability, topology
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## A crash course on group theory

I have just finished a crash course on group theory at Universidade de Lisboa. The notes are here. From the preface: On a visit to Universidade de Lisboa in November 2016, I was asked to give a “crash course” in … Continue reading

Posted in Lecture notes
Tagged Classification of Finite Simple Groups, finite groups, first-order logic, groups of prime power order, infinite groups, Jordan-Holder Theorem, locally finite groups, oligomorphic permutation groups, periodic groups, profinite groups, residually finite groups, Sylow's theorem, topology
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## A precious jewel

One of my favourite textbooks is Simmons’ Introduction to Topology and Modern Analysis. In the introduction, the author distinguishes two types of mathematics: the rare jewels, like the formula saying that the Riemann zeta function evaluated at 2 is π2/6; … Continue reading

Posted in exposition
Tagged pseudo-arc, random graph, Slavomir Solecki, topology, Urysohn space
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