nl en

Soft and Biomatter Theory


Admission Requirements

No special requirements for those admitted to the MSc programme Research in Physics


In soft matter physics we study physical constituents – particles or complex molecules - whose relevant interactions are small enough (often of order kT) that the matter is easily deformed, hence soft. Many soft matter materials and concepts are relevant for biology. In this course you will get an introduction to the most basic soft matter systems and phases, and to the most important concepts to describe and analyze them. Attention is paid to practical (biological) applications. We aim to pay due attention to general applicability of the techniques and concepts, and to connections with other areas of physics.

We will start the course with an elementary introduction to fluid dynamics, elasticity and fluctuation phenomena like Brownian motion. After this we three important examples of soft matter, colloids, polymers and liquid crystals.

The core of the course is formed by 11 lectures of two hours. For the course we will follow the syllabus which is provided, and which contains essentially all the material covered. Six additional exercise classes will deepen your understanding and train you how to do practical calculations or estimates yourself.

Topics covered:
Basics of fluid mechanics and of elasticity theory
The Reynolds number; small Reynolds number hydrodynamics in biomatter
Brownian motion of particles in a fluid
Use of the fluctuation-dissipation theorem to measure stiffness-constants in biomatter
Introduction to Colloids; forces between colloidal particles; clusters; scattering experiments to probe cluster structure;
Elements of polymers: random walks; ideal chains and force extension of ideal chains; wormlike chain model of biopolymers; behavior of chains in solution;
Elements of liquid crystals
Frank elastic energy of liquid crystals

Course objectives

After completion of the course you will be able to

  • critically discuss the concepts and material treated in the course using a blackboard or whiteboard.

  • explain intermediate steps in a line of reasoning in a research paper in the field.

  • explain intermediate steps in the reasoning leading to a Landau-type coarse grained description of a soft matter or biophysical problem, and use the approach to analyse a problem.

  • perform or critically follow a simple linear stability calculation.

  • critically discuss the scaling behavior of long polymers and the relation to critical phenomena.

Transferable skills

After completion of the course you have gained enough background to independently learn about these topics from the specialized literature.


Physics Schedule
For detailed information go to Timetable in Brightspace

Mode of instruction

See Brightspace.

Lecture and tutorials (6 mandatory exercise classes); a syllabus is provided.
Because of the Covid-19 restrictions, the course will be offered online in the fall of 2020. The online mode of instruction will stimulate student participation and discussion, and will include using video's and little clips about important topics.

Assessment method

The assessment is based on two parts:
1. Active participation in the class and exercise class (on an overall pass/fail basis).
2. After the course, students will take an oral exam, at a mutually agreeable date in December or January that fits the student's schedule and preferences. The oral exam will be in person and will take about an hour, and is in the spirit of an informed discussion in front of a traditional blackboard about the course material.

The aim of the oral exam is to test whether you have studied and grasped the material covered in the syllabus. This does not mean, of course, that you need to memorize everything in the syllabus – in fact, you should feel free to take the syllabus or any notes with you to the exam. Think of the exam more as an intelligent discussion about the concepts that were treated in the course. We will use a blackboard or whiteboard, and I might show you some experimental data to discuss these with you in the light of the material that I covered. The exam is in a relaxed atmosphere and we hope that you will actually learn from the oral exam. Professor Schiessel is present at the exam as a second examiner. The final mark for the course is determined by the oral exam.

PhD students who take the course only for pass/fail do not have to do the exercises.

Reading list

The main course material will be covered in a syllabus which the students can obtain online in Brightspace. A printed copy will also be supplied. An additional reader with figures and certain additional material is also provided.
Primary text book: Soft Matter Physics – an Introduction by M. Kleman and O. D. Lavrentovich (Springer 2003).
This book contains many more topics than can be covered in the course, and will therefore also be a useful reference guide during your later studies. We will clearly indicate during the course which parts of the book are used and examined. It is not obligatory, though, to buy this book.


Registration for Brightspace occurs via uSis’ ( How to sign up for classes click here. (


Lecturer: van Saarloos