In the last EMS Magazine (2021/No. 121) Volker Mehrmann reflected in his editorial (link) on the bygone (virtual) European Congress 8ECM. At the end he asked to write to him our opinions about the matters that he addressed, which I did. I want to share here now my e-mail to him with you: Lieber Volker, … Continue reading "Message from the EMS president"
Today I learnt from an article in the QuantaMagazine (link to article) that there is finally a new book trying to explain Freedman’s proof of the 4-dimensional Poincaré conjecture (link to book). The article is fun to read since it contains statements of the involved people about how the whole ‘situation’ about the non-understandable write-up … Continue reading "New book about Freedman’s proof"
Half a year ago Steffen Kionke wrote a blog post on condensed mathematics wherein he mentioned that Peter Scholze put up a challenge to formally verify a key fundamental result of a joint paper with Clausen: a result Scholze terms his most important theorem to date. Today I want to inform you that the mentioned … Continue reading "Computer assisted verification of contemporary mathematics"
Rummaging in the arXiv I ran across this article and the notion of topological complexity which is really appealing. The idea of topological complexity isn’t quite new, it was developed by M. Farber in a short article published in 2003 in Discrete & Computational Geometry. The article doesn’t even have a proper review on MathSciNet, … Continue reading "Topological complexity"
This post is inspired by Alex Engel’s post “Validity of results II” on incorrect results and computer proof checking. Before I get there, let me start with some background first and reveal the connection later. Dustin Clausen and Peter Scholze have put forward the idea of “condensed mathematics” which aims at replacing topological spaces by … Continue reading "Condensed mathematics"
In July I wrote a post about Validity of results. It was about a recent preprint pointing out an erroneous proof in an influential paper. By chance I stumbled yesterday upon this question on MathOverflow: Extent of unscientific, and of wrong, papers in research mathematics. The question starts with a link to Kevin Buzzard’s slides … Continue reading "Validity of results, II"
Recently, I learned that the group G∞ of germs at +∞ of orientation preserving homeomorphisms of the real line has two remarkable properites: it is simple and left-orderable. I thought it is maybe worth to share some background on left-orderability (and why this might be interesting). Let’s start with a definition: A group G is … Continue reading "The group of germs at infinity of line homeomorphisms"
Gestern sind die Ergebnisse der DZHW-Wissenschaftsbefragung veröffentlicht worden. Die Wissenschaftsbefragung ist eine bundesweite repräsentative Trendstudie. [… Sie] versteht sich als langfristiges Barometer der Wissenschaft. Sie ist ein wichtiges Werkzeug zur Untersuchung der Arbeits- und Forschungsbedingungen an deutschen Universitäten und soll ein umfassendes Meinungsbild zur Lage und Entwicklung des deutschen Wissenschaftssystems liefern. Hier ist die Pressemeldung, … Continue reading "Ergebnisse der Wissenschaftsbefragung"