HomeMorphological AnalysisProject ListReference ListDownload ListTutorialAbout ZwickyMA/CarmaGlossaryWicked ProblemsContactCredits-Links-Legal |

Fritz Zwicky

Fritz Zwicky

Developed General Morphological Analysis

Biographical Sketch

Fritz Zwicky is not a household name in science today. He was not a super star of the likes of Einstein, Hubble or Oppenheimer. Yet his influence was significant — far more so, I believe, than his present-day lack of fame would suggest. He was one of the broadest and most inventive scientists of his time, and combined theoretical studies with eminently practical, humanitarian activities.

Zwicky was born in Varna, Bulgaria, in 1898, the son of a Swiss merchant. At the age of 6 he was sent to his father's ancestral district in Switzerland, Glarus, for schooling. Although expected to take up a career in commerce, Fritz' early bent for science apparently persuaded his father to allow him to study engineering instead.

In 1914 he moved to Zürich where he subsequently enrolled in the Swiss Federal Institute of Technology. There he switched to mathematics and experimental physics, wrote his examination essay for no one less than Herman Weyl, and in 1922 took his doctorate with a dissertation on ionic crystals. Three years later he moved to the California Institute of Technology in Pasadena to work with, among others, the great experimental physicist Robert Millikan.

   Coma Cluster
Coma Cluster: Thanks to the Max Planck Institute for Astrophysics

From this point on, Zwicky more or less worked out of Pasadena, both as a faculty member of Caltech (1927-68) and research director/consultant for Aerojet Engineering Corporation (1943-61). He became Professor of Astrophysics at Caltech in 1942 and was a member of the staff of Mount Wilson and Palomar Observatories until his retirement in 1968.

Zwicky has been described as a notorious maverick in science, both brilliant and insufferable. He is primarily known for his work in astrophysics, and especially his comprehensive galaxy surveys. However, he thrived on investigating and theorizing about extreme phenomena and the boundary conditions of different problems. This lead him both to develop a method for systematically investigating multi-dimensional problem complexes, and to formulating a number of hypotheses which represented significant breakthroughs in astronomy.

Zwicky and Walter Baade were the driving forces behind acquiring and installing the first Schmidt telescope to be used in a mountain-top observatory -- the famous 18-inch Palomar Schmidt -- in 1935. Schmidt's revolutionary new telescope made it possible to photograph large areas of the sky quickly, with little distortion. Zwicky used it to make the first rapid survey of the heavens, mapping out hundreds of thousands of galaxies (now called the Zwicky Galaxy Database). As a result of this, Zwicky discovered that galaxies tended to cluster, opening up a new chapter in the history of astronomy and cosmology. At the same time, he applied the virial theorem to the Coma cluster of galaxies and obtained evidence of unseen mass, thus starting off the debate on what is now called dark matter. (The 18-inch Schmidt was later used by Gene and Carolyn Schumaker to discover the comet Schumaker-Levy 9, which crashed into Jupiter.)

Pursuing the idea that "bright novae" were of fundamental interest for determining the distance to far-off galaxies, he and Walter Baade coined the term supernova (Baade & Zwicky, 1934a). These, Zwicky proposed, marked the transition from ordinary stars to neutron stars -- which he was the first to hypothesize -- and were the origin of cosmic rays (Baade & Zwicky, 1934b). This was an amazing (and correct) triple hypothesis and was an important step in the still on-going project to determine the size and age of the (visible) universe. (Zwicky's neutron star-hypothesis finally entered mainstream astronomy in the 1960's). In 1937 Zwicky proposed that galaxies could act a gravitational lenses.
   Zwicky at the 18-inch Schmidt
Zwicky at the 18-inch Schmidt: Thanks to the Jet Propulsion Laboratory Archives.

Besides numerous other contributions to astrophysics, Zwicky was active in the aerospace industry. Just after WWII, he was appointed head of the U.S. Air Force teams that went to Germany and Japan to evaluate wartime research on jet propulsion. He was director of research at Aerojet Engineering and was involved in the development of jet and rocket propulsion systems -- for which he obtained a number of patents. He is credited by some as being the "father" of the modern jet engine.

On top of all this, Zwicky was engaged in a number of charitable activities, including his work to help rebuild scientific libraries destroyed during the war and participating in the Pestalozzi Foundation's program to establish war orphan villages. He was also vice president of the International Academy of Astronautics, where he promoted a program of space law.

Zwicky developed his "morphological approach" -- or general morphological analysis -- as a method for structuring and investigating the total set of relationships contained in multi-dimensional, usually non-quantifiable, problem complexes (see General Morphological Analysis). He applied this method inter alia in astrophysics, in the development of propulsive power plants and propellants, and to the legal aspects of space travel and colonization. He founded the Society for Morphological Research and enthusiastically advanced "General Morphology" for some 40 years – between the early 1930's until his death in 1974. Morphological analysis goes through iterative steps or phases which represent cycles of analysis and synthesis - the basic method for developing (scientific) models (Ritchey, 1991).

*    *    *

The Author: Dr. Tom Ritchey is a former Research Director for the Institution for Technology Foresight and Assessment at the Swedish National Defence Research Agency (FOI) in Stockholm. He is a methodologist and facilitator who works primarily with non-quantified decision support modelling -- especially with General Morphological Analysis (MA), Bayesian Networks (BN) and Multi-Criteria Decision support. Since 1995 he has directed more than 80 projects involving computer aided MA for Swedish government agencies, national and international NGO:s and private companies. He is the founder of the Swedish Morphological Society (www.swemorph.com) and Director of Ritchey Consulting.


Baade, Walter & F. Zwicky, “On Super-Novae,” Proc. of the Nat. Acad. of Sci. 20, 254 (1934a).

Baade, Walter & F. Zwicky, “Supernovae and Cosmic rays,” Physical Review 45, 138 (1934b).

Ritchey, T., "Analysis and Synthesis - On Scientific Method based on a Study by Bernhard Riemann", Systems Research 8(4), 21-41 (1991, revised 1996).   [Download in PDF]  

Zwicky, F., "Morphological Astronomy", The Observatory. Vol. 68, No. 845, Aug. 1948, S. 121-143.  [Download in PDF]  [Caution: This file is 2.6 Mb]  Thanks to The Obseravtory.

Principal works in English by Zwicky on General Morphological Analysis:

Zwicky, F., Discovery, Invention, Research - Through the Morphological Approach, Toronto: The Macmillian Company, 1969.

Zwicky, F. & Wilson A. (eds.), New Methods of Thought and Procedure: Contributions to the Symposium on Methodologies. Berlin: Springer, 1967.

Biographical information on Fritz Zwicky can be found here:

Alfred Stöckli & Roland Müller. Fritz Zwicky – An Extraordinary Astrophysicist.
Cambridge Scientific Publishers, Cambridge, 2011. ISBN 978-1-904868-78-1

Book Review: "Fritz Zwicky: An Extraordinary Astrophysicist "  by Tom Ritchey.
Acta Morphologica Generalis, Vol 1, No 3. (2011)

Remembering Zwicky  by Jesse Greenstein
Engineering and Science 37:15-19, 1974. Thanks to the Swiss Fritz Zwicky Foundation.

Idea Man  by Stephan M. Maurer
A recent short biography of Zwicky and his scientific exploits. Thanks to Beamline.

HomeMorphological AnalysisProject ListReference ListDownload ListTutorialAbout ZwickyMA/CarmaGlossaryWicked ProblemsContactCredits-Links-Legal |

About Fritz Zwicky