| Pierre Weiss | |
|---|---|
|   | |
| Born | 25 March 1865 Mulhouse | 
| Died | 24 October 1940 (aged 75) Lyon | 
| Nationality | French | 
| Fields | Physics | 
| Known for | Ferromagnetism | 
Pierre-Ernest Weiss (25 March 1865 – 24 October 1940) was a French physicist who developed the domain theory of ferromagnetism in 1907.Weiss domains and the Weiss magneton are named after him. Weiss also developed the Molecular or Mean field theory, which is often called Weiss-mean-field theory.
Weiss was born in Mulhouse and died in Lyon.