Louis Néel was a French physicist who shared, with Hannes Alfvén, the 1970 Nobel Prize in Physics for his work on the magnetic properties of solids. Néel discovered antiferromagnetism, in which the magnetic fields of small groups of atoms are aligned in opposite directions. His research not only permitted the manufacture of products used in, for example, computer memories, but also explained phenomena such as the recording by certain of the Earth's rocks of geomagnetic fields.