3 July 1887 - Birth of Hendrika Johanna van Leeuwen, physicist known for her contributions to the theory of magnestism

The daughter of Professors Pieter Eliza van Leeuwen and Maria Wilhelmina Schepman, Hendrika Johanna van Leeuwen was born in The Hague on 3 July 1887.

After secondary school in her hometown, she continued her training in physics at the University of Leiden, under the supervision of Hendrik Antoon Lorentz. In 1919, he obtained his Ph.D., whose thesis entitled "Problems of the electronic theory of Magnetism" focused on explaining why magnetism is essentially a quantum mechanical effect (a result now known as the Bohr-van Leeuwen theorem). In this respect, Van Leeuwen was unaware of the results presented 8 years earlier by Niels Bohr also in his doctoral thesis.

During and after his Ph.D. research, he taught in secondary schools. In September 1920, he became a practical assistant at the Technische Hogeschool in Delft. After over twenty years, Van Leeuwen received a permanent appointment in 1943 as a senior theoretical and applied physics assistant. This allowed her to conduct her research, including the so-called permeability of ferromagnetic metals such as iron and nickel.

In 1947 she was appointed professor at the TH Delft, becoming the first woman professor at this institution. Until her retirement in 1952, she lectured on ferromagnetism and special relativity.

Hendrika Johanna van Leeuwen died at her home in Delft, the Netherlands, on 26 February 1974, aged 86.