The cat's cradle, stirring, and topological complexity

There are several physical situations in which the tangling of a loop is relevant: the game of cat's cradle is a simple example, but a more important application involves the stirring of a fluid by rods. Here we discuss how elementary topology constrains the types of mappings that can occur on a surface, for example when the surface is the domain of a two-dimensional fluid.

Two jobs, two countries, two homes

Yulij Il’yashenko is well known in the dynamical systems community for his work on the 16th Hilbert problem, generic properties of dynamical systems, and non-local bifurcations. He works part-time both at Cornell University in the USA and at Moscow State University, the Independent University and the Steklov Institute in Russia. Hinke Osinga asked him what it was like to grow up in the former USSR and how he has come to enjoy his life split between two continents.

The Dynamics of Toys

Many mechanical toys display compelling and subtle dynamical properties. This article includes both modeling and experimental data for two classical examples: The drinking bird, and the balancing stick.

Dynamical Systems and Climate: Opportunities for Involvement

Mary Lou Zeeman describes the state of dynamical systems activities and opportunities in the field of Climate dynamics and modeling. This article is a follow up to Zeeman's May 2008 article Climate Math in San Diego.

Sensor Networks, Algebraic Topology, and Dynamics

Robert Ghrist gives an overview of how algebraic topology and dynamical systems are being applied to the engineering problem of sensor placement and data collection. Ghrist's work in this field with collaborator Vin de Silva, Pomona College earned them a 2007 SciAm 50 award, Scientific American's list of the fifty most important advancements in technology and innovation.

Cultural and culinary delights with AUTO

Eusebius Doedel is famous in dynamical systems as the man behind the software package AUTO. He is (almost) equally well known for his many travels and his love for good wine and good food, not to mention a good cigar! Hinke Osinga asked him how he managed to satisfy his appetite for foreign cultures and travel during his academic career at Concordia University, where he has worked since 1979.

Viscosity movie: a big hit on YouTube

In 2003, Robert Deegan, Florian Merkt, and Harry Swinney created a research video on holes and fingering in a vibrating particulate suspension. Deegan describes the process by which this became popular YouTube, with over 1.5 million hits and many imitators.

Interview with Freddy Dumortier

Freddy Dumortier is well known for his work in bifurcation theory, blow-up techniques and slow-fast systems. His 60th birthday was celebrated in April 2007 in Hasselt and Brussels with the conference Dynamics in Perturbations. Bernd Krauskopf used this opportunity to talk to him at the Belgian Academy of Sciences Building about his views on the field of dynamical systems.

The answer after a lunch with Arnol'd

Gábor Domokos has written two papers in the 2006 fall issue of The Mathematical Intelligencer, one of them with Péter Várkonyi, on results that arose in answer to a question posed by Arnol'd. Springer has been so kind to permit us reproducing these publications: "My Lunch with Arnol'd" by Gábor Domokos, pages 31-33, and "Mono-monostatic bodies: The answer to Arnold's question" by Péter Várkonyi and Gábor Domokos, pages 34-38, of The Mathematical Intelligencer 28(4) (2006).