Geertruida de Haas-Lorentz

Geertruida Luberta de Haas-Lorentz
De Haas-Lorentz in 1927
Born	Geertruida Luberta Lorentz (1885-10-20)October 20, 1885 Leiden, Netherlands
Died	1973 (aged 87–88) Leiden, Netherlands
Alma mater	University of Leiden
Known for	first to perform fluctuational analysis of electrons as Brownian particles
Spouse	Wander Johannes de Haas
Children	4
Parents	Hendrik Lorentz (father) Aletta Catharina Kaiser (mother)
Scientific career
Fields	Physics
Institutions	Technical University of Delft
Thesis	Over de theorie van de Brown'schen beweging en daarmede verwante verschijnselen (1912)
Doctoral advisor	Hendrik Lorentz

Geertruida Luberta "Berta" de Haas-Lorentz (20 November 1885 – 1973) was a Dutch physicist and professor of the Technical University of Delft. She was the first to theoretically study thermal fluctuations in electric circuits, treating electrons as Brownian particles. Consequently she is considered one of the pioneers of electrical noise theory. She was the daughter and doctoral student of Hendrik Lorentz. She went by the name Berta, or Ber.^[1]