Tag Archives: Axiom of Choice

Infinity and Foundation

Posted on 16/07/2017 by

After the reviving effect of a week’s holiday, I have been thinking about Zermelo–Fraenkel set theory, inspired by a very nice student project I supervised (about which I hope to say something here sometime soonish). I have come across a … Continue reading →

Posted in exposition | Tagged , , , , , | 9 Comments

Thoughts on topology

Posted on 16/04/2016 by

As well as Advanced Combinatorics, I have been teaching Topology this semester. This is something I had not taught for many years. I was only teaching half the module: the first half had been given, and the notes prepared, by … Continue reading →

Posted in teaching | Tagged , , , , | 4 Comments

Automorphisms of groups

Posted on 05/11/2011 by

I set a question to my group theory class. It is quite easy until suddenly you find yourself falling off a cliff into deep water. Indeed, I don’t know the answer to the second part of this question. Show that … Continue reading →

Posted in exposition, open problems | Tagged , , , | 4 Comments