SPP 2026 – Geometry at Infinity

Blaschke’s Inclusion Theorem

An extremely classical theorem from planar geometry is the following one: If \(B_1\) and \(B_2\) are two strictly convex, compact planar domains with smooth boundaries touching at some point \(p \in \partial B_1 \cap \partial B_2\) with common inner normal, then \(B_1 \subset B_2\) provided that the curvatures \(k_i(\nu)\) of the boundaries satisfy \(k_1(\nu) \ge … Continue reading

A Mathematical Conventions Survey

I wanted to share the results of this funny survey with you: 100 Questions About Mathematical Conventions. But beware, if you click on the link you will loose an hour of your life time. 😉

Rationalized stable homotopy groups of spheres

Computing the stable homotopy groups of spheres \(\pi_*^s\) is a major problem in stable homotopy theory. In chromatic homotopy theory one studies, for every prime \(p\), a tower \[\cdots \to L_n\mathcal{S} \to \cdots \to L_1\mathcal{S} \to \mathcal{S}_\mathbb{Q}\] over the rational sphere spectrum \(\mathcal{S}_\mathbb{Q}\) whose homotopy limit is the \(p\)-localization \(\mathcal{S}_{(p)}\) of the sphere spectrum. Since … Continue reading

Ars legendi-Fakultätenpreis Mathematik 2024

Der diesjährige Ars legendi-Fakultätenpreis für exzellente Hochschullehre in der Mathematik geht an Prof. Anselm Knebusch. Prof. Anselm Knebusch von der Hochschule für Technik Stuttgart setzt das innovative Konzept des “computerbasierten Lernens im Hörsaal” ein, um der Heterogenität der Studienanfänger in der Mathematikausbildung der Ingenieursstudiengänge zu begegnen. Zur Aktivierung der Studierenden wird der neue Ansatz des … Continue reading

Abel Prize 2024

The Abel Prize 2024 goes to Michel Talagrand for his groundbreaking contributions to probability theory and functional analysis, with outstanding applications in mathematical physics and statistics.

Metric spaces and C*-algebras III

This is a continuation of the previous two posts I and II. In the first one I defined the uniform Roe algebra \(C_u^*(X)\) of a metric space \(X\) of bounded geometry and mentioned the following interesting result: Two metric spaces \(X\) and \(Y\) are coarsely equivalent if and only if their uniform Roe algebras \(C_u^*(X)\) … Continue reading

Isoclinism of groups

Do you know when two groups \(G\) and \(H\) are called isoclinic to each other? I have never heard of this notion before, but there was a paper on the arXiv listing today using it in its abstract; so I looked in this paper, not because I was interested in its content, but just because … Continue reading

Analysis, Geometry and Topology of Positive Scalar Curvature Metrics

I wasn’t traveling much (actually, almost not at all) to conferences or workshops in the last few years. First because of the COVID-19 pandemic and afterwards because I got a child and was on parental leave for a long time. This will change this year and right now I am on the Oberwolfach Workshop Analysis, … Continue reading