## Wavys Werk und Davids Beitrag

#### Wer ist schon gern berechenbar? Ein Gespräch mit einer Welle über ihre Simulationen.

via GIPHY

Stimme aus dem Nichts: Warum hat Gott nicht gesprochen „Es werde Schall!“?

Ich: Keine Ahnung.

Stimme aus dem Nichts: Hat er schon, es hat nur niemand gehört.

Ich: Sehr witzig. Wer ist da und warum sehe ich dich nicht?

Stimme aus dem Nichts: Ich bin Wavy, die akustische Welle. Du kannst mich nicht sehen, sondern
nur hören.

Ich: Das ergibt Sinn. Ich heiße David. Es freut mich dich endlich kennen zu lernen. Ich habe meine
Doktorarbeit über dich geschrieben.

Wavy: Ach ja? Um was geht es darin?

Ich: Ich habe Fehlerabschätzungen für Finite Elemente Lösungen von Wellengleichungen mit
dynamischen Randbedingungen bewiesen.

Wavy: Wie bitte? Wenn du glaubst mich durch „Fachchinesisch“ beeindrucken zu können, hast du
dich geschnitten.

Ich: Natürlich nicht, verzeih mir. Dann lass mich mit einer Frage beginnen: Weißt du wie ein
Mikrofon funktioniert?

## Merry Christmas

We wish you a merry christmas with this blackboard art by David Hipp, Andreas Sturm et al.

## 5th International Conference on Elliptic and Parabolic Problems

f.l.: Rainer Mandel, Janina Gärtner, Piotr Idzik, Andreas Hirsch, Wolfgang Reichel

From May 22nd till May 26th the 5th International Conference on Elliptic and Parabolic Problems took place in Gaeta, Italy. With 17 invited talks and 184 short talks in 19 minisymposia distributed on four and a half days the amount of talks at the conference was quite impressive. Besides the more than 200 participants from all over the world there were six researchers from the CRC: Wolfgang Reichel who had the honour to give the opening talk; Janina Gärtner, Andreas Hirsch, Piotr Idzik, Rainer Mandel and Martin Spitz, all of them contributing by a short talk to the minisymposium “PDEs arising in nonlinear optics”. In this minisymposium consisting of 14 talks, which was organised by Jarosław Mederski and Wolfgang Reichel, we were kept up to date with the ongoing research of colleagues who are well-known to our working groups in Karlsruhe. Continue Reading →

## Women in PDEs @ Karlsruhe

On April 27-28, 2017 the workshop “Women in PDEs @ Karlsruhe” will take place. The aim of this workshop is to provide a platform to bring together students of mathematics (in Bachelor or Master programs), young researchers (PhD students and postdocs) and established female mathematicians from academia and industry working on partial differential equations (PDEs). Outstanding invited speakers will give talks on their current research topics. A panel discussion will give the possibility to discuss questions not only concerning research but also career choices/planning and practical questions of managing career and family.

## What is Bifurcation Theory?

In the following I would like to present the main ideas of bifurcation theory along with some basic examples that illustrate the theory. For the sake of shortness let me formulate the fundamental question of bifurcation theory in an abstract way. Suppose you are given an equation $$F(x,\lambda)=0$$ with the property that $$x=0$$ is always a solution, the so-called trivial solution. Is it possible to find some $$\lambda^*$$ such that a sequence of nontrivial solutions converges to $$(0,\lambda^*)$$? In other words: Do nontrivial solutions bifurcate from the trivial solutions? In the following I will present three equations from analysis, linear algebra and ordinary differential equations showing that bifurcation theory is a topic worth studying! The reading requires some amount of advanced mathematics — do not hesitate to contact me if you need some additional explanations. By the way: Next semester I will give a lecture on that topic which is suited for master students or advanced bachelor students with a background in analysis, differential equations and possibly boundary value problems, see below for more information. Continue Reading →