Tag Archives: commuting graph

Graphs on groups, 10

Posted on 01/01/2022 by Peter Cameron

The lesson of this post and the next in the series is that the most interesting questions (to me, anyway) are not about the girth of the deep commuting graph but instead about the classes of groups G defined by … Continue reading →

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Graphs on groups, 5

Posted on 26/03/2021 by Peter Cameron

I gave two lectures on this stuff to a new research seminar on Groups and Graphs, run by Vijayakumar Ambat in Kochi, Kerala. The first was an introduction to the hierarchy, the second was about cographs and twin reduction, why … Continue reading →

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Graphs on groups, 2

Posted on 27/01/2021 by Peter Cameron

I wrote the long post about this to try to write it out of my system. No luck … I mentioned in that survey that every finite graph is embeddable as induced subgraph in the enhanced power graph, deep commuting … Continue reading →

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Graphs defined on groups

Posted on 23/01/2021 by Peter Cameron

I’ve been spending time I can ill afford on various questions related to graphs whose vertex set is a group G and which capture some of the structure of G. (I interpret this to mean that the graph is invariant … Continue reading →

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Induced subgraphs of power and commuting graphs

Posted on 16/12/2020 by Peter Cameron

For those who like thinking about these things, here is a small observation and a few problems. As I have recently discussed, the power graph of a group is perfect. This means that all its induced subgraphs are perfect, and … Continue reading →

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Graphs defined on groups

Posted on 04/12/2020 by Peter Cameron

Apologies; I have been so busy lately that very little has got written up. Let me try to remedy this with a quick tour through some recent mathematical developments. As some of my posts have hinted, one topic I have … Continue reading →

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Perfectness of the power graph

Posted on 04/10/2020 by Peter Cameron

The power graph of a group is the graph whose vertices are the group elements (sometimes the identity is excluded but it doesn’t matter here), in which x and y are joined if one is a power of the other. … Continue reading →

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Groups and graphs

Posted on 08/09/2020 by Peter Cameron

Two new preprints have appeared on the arXiv (2008.09291 and 2009.02884), about which I would like to say something. One is by Saul Freedman, the other by him and two co-authors (his PhD supervisors). The intersection graph of a group … Continue reading →

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The power graph yet again

Posted on 15/03/2016 by Peter Cameron

Five years ago, I posted a short update on the power graph of a group. Now, finally, the paper resulting from this has appeared on the arXiv; my coauthors are Ghodratollah Aalipour, Saieed Akbari, Reza Nikandish and Farzad Shaveisi. I … Continue reading →

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