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# Author Archives: Peter Cameron

## A trip to Coimbra

The University of Coimbra is the oldest in Portugal, having been founded in 1290 (younger than Oxford, older than St Andrews), but after bouncing back and forth between Coimbra and Lisboa for a while, it finally settled in Coimbra in … Continue reading

Posted in events, geography, history
Tagged Bussaco forest, Coimbra fado, Conimbriga Roman town, the random graph
3 Comments

## Pedro Nunes

Pedro Nunes was a Portuguese mathematician of the sixteenth century, perhaps the greatest mathematician of his time in Europe. Yesterday I was treated to a very informative short presentation about Nunes and his work by the historian of science Henrique … Continue reading

## Quieter times

Things have been a little quieter for the last couple of weeks. Tomorrow, off to Portugal for a week and a half, then the Czech Republic for a week, then a couple of weeks to catch my breath before New … Continue reading

Posted in Uncategorized
Tagged awesome comics, decommissioning, graph partitions, switching classes
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## Primitive switching classes

Last year I wrote here about switching classes of graphs for which the switching class has a primitive automorphism group. (I repeat the definitions briefly below.) I conjectured that, except for the trivial switching classes of the complete and null … Continue reading

Posted in exposition, mathematics
Tagged Akos Seress, Don Taylor, Pablo Spiga, primitive group, switching class, two-graph
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## Spitalfields photos

Take a look at these astonishing photographs … http://spitalfieldslife.com/2014/06/29/an-astonishing-photographic-discovery/

## Automorphism groups of hypergraphs

I am getting old and forgetful, but I don’t think I said anything here about this problem yet. If I did, apologies for the repetition – but there is something new to report! In April, Laci Babai and I finally … Continue reading

Posted in exposition, mathematics
Tagged Akos Seress, hypergraphs, Laci Babai, Pablo Spiga, primitive groups
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## Metrics

HEFCE had a consultation on metrics. I found out about it too late to send in a submission. But you may want to read what two people whose opinions I respect, David Colquhoun and David Spiegelhalter, have to say.

## Busy times, 10: in Waterloo

After a week in London, off to Waterloo for Chris Godsil’s 65th birthday conference. The week at home was no holiday: among other things I managed to read and examine Christopher Harden’s PhD thesis (a nice study of fixed point … Continue reading

Posted in events
Tagged algebraic graph theory, antipodean animals, Chris Godsil, Elora, perfect state transfer, quantum, sandwiches, Waterloo
2 Comments

## A five-finger exercise

This morning at the Godsil 65 conference, Cheryl Praeger was wearing a T-shirt she was a bit ashamed of. It had been produced by the Australian Mathematics Trust to commemorate Niels Abel’s anniversary, and featured a quintic equation (he was … Continue reading

## Almost highly transitive

I want to discuss a concept I have known about for quite a long time, but never found any real use for. Suggestions welcome! Highly transitive groups A permutation group is n-transitive if it has a single orbit on the … Continue reading

Posted in Uncategorized
Tagged generic, Henson's graph, homogeneous, multiorders, orders, Petrov-Vershik measure, random graph, universal
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