Tag Archives: derangements

More on derangements

Posted on 04/04/2020 by Peter Cameron

Francis Bacon, in The New Organon, developed a famous metaphor: Those who have handled sciences have been either men of experiment or men of dogmas. The men of experiment are like the ant, they only collect and use; the reasoners … Continue reading →

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Perth, week 4

Posted on 08/10/2016 by Peter Cameron

And now the time in Adelaide and Perth is over. We are back in London, having arrived on the same day as we left Australia. This was the first time I have done this, and I really don’t recommend it. … Continue reading →

Posted in exposition, synchronization | Tagged , , | 2 Comments

Perth, week 1

Posted on 18/09/2016 by Peter Cameron

The first week of the visit is over. The weather has been quite cold, but it is likely to improve as time goes on. The best day so far was yesterday, when we went to Yanchep National Park and had … Continue reading →

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Green on derangements

Posted on 26/05/2016 by Peter Cameron

I have to mention Ben Green again. Yesterday he gave a lovely colloquium talk on a problem I had cracked my head against some years ago without much success. As usual with derangements, the story begins with a classical result: … Continue reading →

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Asymptotic group theory, 2

Posted on 19/08/2015 by Peter Cameron

Inna Capdeboscq started proceedings this morning with a talk about one small part of the second-generation (Gorenstein–Lyons–Solomon) proof of the Classification of Finite Simple Groups. What she described will be volume 8 of the complete proof, if I remember correctly. … Continue reading →

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Finding derangements without CFSG

Posted on 18/01/2013 by Peter Cameron

Nearly two years ago, I posed the problem of finding an “elementary” deterministic polynomial-time algorithm for finding a fixed-point-free element (or derangement) in a transitive permutation group. The background is that there are so many fpf elements (at least a … Continue reading →

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Pretty structures

Posted on 08/05/2011 by Peter Cameron

I was at the Pretty Structures conference in Paris last week. The original conference in what became this sequence was called Pretty Things. Perhaps this is not serious enough for a meeting held at the Institut Henri Poincaré, I don’t … Continue reading →

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