Utrecht Science Murals

Scientists working at Utrecht Unversity have made important contributions to chemistry and physics. Noticeable examples include Nobelprize winners Jacobus van ‘t Hoff, Peter Debye, and Gerard ‘t Hooft. Another example is the the foundation of the Royal Netherlands Meteorological Institute (KNMI) in 1854 by Christophorus Buys Ballot.
Inspired by the Wall Formulas project in Leiden, Sander Kempkes and Ingmar Swart of the Science faculty at Utrecht University aim to showcase the achievements and contributions made by Utrecht scientists to society.

The paintings are realized by ‘De strakke Hand‘, a group of local artists.

First measurement of the Doppler in 1845 effect by Prof. Buys Ballot (1817 – 1890)

The Doppler effect

Explanation: If the source of a (sound) wave moves relative to an observer, the frequency of the wave perceived by the observer changes. A well-known example is the pitch of a car horn as it approaches you or moves away from you.

Example of the Dopplereffect

Utrecht link: Buys Ballot was the first to experimentally verify the existence of the Doppler effect. He did so by placing a hornblower on a train riding over the newly opened track between Utrecht and Maarssen.

More information: People who would like to know more can read about the Doppler effect on Wikipedia.

Location of the painting
Ornstein-Uhlenbeckprocess, codeveloped by Prof. Ornstein in 1930

The random walk

Explanation: A drunk person does not move in a straight line. Sometimes, the step is the forward direction, sometimes to the sides, and sometimes backwards. This is an example of a random walk (‘toevalsbeweging’ in Dutch). 

Example of a random walk in two dimensions

The random walk is used to describe a huge number of widely different phenomena, ranging from the motion of oil dropplets in milk, the elasticity of rubber, the motion of birds looking for food, to the stock-market. 

Utrecht component: Together with Prof. George Uhlenbeck – professor in Utrecht from 1935 – 1938, Prof Leonard Ornstein developed a mathematical framework to describe the random walk.

Location of the painting
Molecules can have mirror images (1874), by Jacobus Henricus van ‘t Hoff (1852 – 1911)


Your left and right hand look very much alike: both have four fingers and a thumb. However, if you look more closely, you will realize they are not identical; they are each others mirror image. In the same way, molecules can also exist as mirror images. This phenomenon is known as stereochemistry. It is exceedingly important for many reasons. For example, in medicine, one molecule can act as a potent drug to treat diseases, while it’s mirror image is poisonous. 

Utrecht component: the foundations of Stereochemistry were laid down in a publication in 1874 by Van ‘t Hoff while he was a Ph.D. student at Utrecht University.  Later, he won the first Nobelprize in Chemistry for other work.

More information: the original publication ‘La chimie dans l’espace’ (in French) can be found here. The Kahn Academy has nice video’s about stereochemistry, to be found here.

Location of the painting

The mural paintings are made possible by financial support from the Faculty of Science, the Department of Physics,  the Department of Chemistry, the Institute for Theoretical Physics, the Debye Institute for Nanomaterials Science the Delta Institute for Theoretical Physics and Stichting Physica.