Walter M. Elsasser

Walter M. Elsasser was a German-American physicist who made significant contributions to the field of astronomy. His most notable work involves the development of the dynamo theory, which provides an explanation for the Earth's magnetic field. According to this theory, the magnetic field is generated by electric currents induced in the fluid outer core of the Earth. Elsasser's work on the Earth's magnetic field also led to the understanding that the history of this field can be determined by analyzing the magnetic orientation of minerals in rocks.

In addition to his work on the Earth's magnetic field, Elsasser is also recognized for his early proposal regarding the wavelike nature of electrons. Although his idea remained unpublished, it preceded the Davisson–Germer experiment, which demonstrated the diffraction of electrons sent through a crystal and ultimately led to a Nobel Prize in Physics. Elsasser's contributions to the field of physics, particularly in the areas of geomagnetism and the behavior of electrons, have had a lasting impact on our understanding of the Earth and the physical world.