Soft Matter

Concepts, Phenomena, and Applications

2. Elasticity

The additional material is organized according to book sections and it includes links to (review) papers mentioned in the book, videos of different phenomena we discuss (experiments and simulations), as well as links to online lectures that address certain topics in more details.

2.4 The Poisson ratio       

A brief online lecture by The Efficient Engineer on the Poisson ratio, with several examples of materials.

2.5 Frequency dependent shear modulus

Maxwell and Kelvin-Voigt spring-dashpot model illustrated explicitly. From JolyNYU.

2.6 A brief foray into elastodynamics

Four lectures on Computation geometry of soft matter by Chris Rycroft, given at the 2024  Amherst summer school on Soft Solids and Complex fluids. The lectures touch on several topics treated in various chapters. Lecture 1, Lecture 2, Lecture 3, Lecture 4.

2.7 Bending is the low-energy deformation of sheets and rods

The video shows a triangular polymer sheet wrapping around a water droplet. This effect causes soft contact lenses to attach to your eye. From MecaWet group at ESPCI (Benoît Roman, José Bico and Etienne Reyssat).

2.8 Static shapes and buckling of rods

Online lectures on buckling. Left: From PurdueMET. Right: From The Efficient Engineer.

buckling

Thick beams normally don’t buckle. This beam in the metro station under the World Trade Center buckled due to the sudden impact of the collapse of the WTC on 9/11. Judging by the eye, a higher order buckling mode (see problem 2.4) played a role too.

2.9 Metamaterials with negative Poisson ratio

Demonstration of auxetic materials.
Left: From Jae-Hwang Lee. Right: From Architectural Design Computing

Application of auxetic materials in clothing. From Two Minute Papers.

Videos from van Hecke Lab of a material with holes under compression.

Four lectures on mechanical metamaterials by Katia Bertoldi at the Umass summer school.
Lecture 1, Lecture 2, Lecture 3, Lecture 4.

2.10 Packing of particles jammed together

A talk by Heinrich Jaeger on Acoustically levitated granular matter. Talk starts at 1.35 minutes.

2.12 Topological Mechanics

Waves in gyroscope lattice and wave on a spinner fluid from Irvine lab. More can be found on William Irvine’s lab website.

Mechanical topological material from Vitelli’s lab together with a short intro to topological mechanics by Vincenzo Vitelli.

A lecture by Xiaoming Mao on “Vibrational modes and rheology of generic mechanical networks”.

A lecture by Tom Lubensky on
“Elasticity and Topological Mechanics”.

A lecture by Vincenzo Vitelli on
“Topological Mechanics”

2.14  Box 2: Summary of Landau theory

Two lectures on Landau theory by Jonathon Riddell.

Mehran Kardar‘s lecture on Landau theory.
From MIT Open Course Ware.

Problems

Problem 2.9: build your own topological insulator. If you have lego pieces handy, this scheme will allow you to build a mechanical topological insulator. See also the video from Vitelli lab in section 2.12 of this page.

Coding Problems

Our aim is to make coding problems available for all chapters, including this one, by the end of 2025.