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# Tag Archives: Steiner systems

## Synchronization and all that, 2

The story I told in the last post is not over. The recent development is that we spotted a mistake in the paper. An easy mistake to make: we had simply used the symbol n in two different places with … Continue reading

Posted in doing mathematics, exposition
Tagged association scheme, large sets, ovoid, Philippe Delsarte, quadric, spread, Steiner systems, synchronization, triality
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## EKR, Steiner systems, association schemes, and all that

A great number of mathematical problems amount to looking in a large but highly structured graph, and finding a complete or null subgraph of largest possible size there. For a simple example, consider Latin squares of order n. One of … Continue reading

## Steiner systems exist, 2

One of the inevitable consequences of getting old is that my brain becomes more and more like a Swiss cheese, and important pieces of information fall through the holes. So I owe an apology to Michael Braun, Tuvi Etzion, Patric … Continue reading

## Combinatorics in Scotland, group theory in Portugal

I never really wanted to retire. For various reasons which no longer matter, I decided to retire from my position at Queen Mary, University of London, on turning 65 two years ago. I hoped that I would find enough to … Continue reading