In a couple of days I’ll be blogging for 4 years… and I’m in the process of resurrecting about 300 posts from a database-dump made in june. For example here’s my first post ever which is rather naive. This conversion program may last for a couple of weeks and I apologize for all unwanted pingbacks it will produce.

I’ll try to convert chunks of related posts in one go, so that I can at least give them correct self-references. Today’s work consisted in rewriting the posts of my virtual course, in march of this year, on dessins d’enfants and its connection to noncommutative geometry (a precursor of what Ive been blogging about recently). These posts were available through the PDF-archive but are from now on open to the internal search-function. Here are the internal links and a short description of their contents

- The best rejected proposal ever on Grothendieck’s programme and Belyi maps.
- Monsieur Mathieu on the dessins of $M_{12} $ and $M_{24} $.
- The cartographers’ groups 1 on the free product structure of $PSL_2(\mathbb{Z}) $ and related groups.
- The cartographers’ groups 2 continuation and a simpler proof due to Alperin.
- Anabelian geometry on sources of representations of the modular group.
- The noncommutative manifold of a Riemann surface a mental picture to get all finite dimensional representations of the coordinate ring of a curve.
- Noncommutative curves and their manifolds extension to twisted curves.
- Permutation representations of monodromy groups how dessins give such representations.

Besides, I’ve added a few scattered old posts, many more to follow…

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