Scientific Milestones

Generations of Caltech faculty, alumni, and students have made important contributions to science and engineering research.

A sampling of some of Caltech's historic achievements in science:

The Discovery of Anti-matter

Carl Anderson In 1934, Caltech physicist Carl Anderson discovered the anti-electron, or positron, the first empirical proof for the existence of anti-matter. In addition to providing inspiration for decades of science-fiction writers, Anderson's discovery permanently reshaped our view of the universe and opened major new avenues of investigation in modern physics. He was awarded the Nobel Prize in 1936.

The Nature of the Chemical Bond

Linus Pauling What has been called the single most important discovery in the history of chemistry was made at Caltech in the 1930s by Linus Pauling. Pauling determined the nature of the chemical bond: how atoms link up to form molecules in both living and nonliving systems. Up to that time, chemistry had essentially been a hit-or-miss proposition; Pauling's insight handed chemists a powerful new tool for both predicting and manipulating the outcome of chemical reactions. Major advances in chemistry and molecular biology, and the creation of hundreds of synthetic products, had their roots in this single discovery. Pauling won the Nobel Prize twice: for chemistry, in 1954 and for peace, in 1962.

The Foundations of Molecular Biology

Thomas Hunt Morgan Between 1930 and 1960, a remarkable group of biologists at Caltech played a central role in creating the science of molecular biology. They included Thomas Hunt Morgan (1933 Nobel laureate), whose studies of the relationship of chromosomes to heredity laid the foundations for much of modern biology, and George Beadle (1958 Nobel laureate), who discovered much of what we now know about the chemical activity of genes. Beginning in the 1940s, Caltech's Max Delbruck, a physicist turned biologist, introduced the rigorous techniques of physics to the study of biology and made fundamental discoveries concerning the nature of viruses and viral disease. He received the 1969 Nobel Prize for his work.

The Birth of Modern Earthquake Science

Charles Richter Four Caltech scientists, working in the 1920s and early 1930s, played a pivotal role in developing seismology into an international science of earthquake study, detection, and measurement. Seismologist Harry Wood and astronomer John Anderson invented a sensitive seismograph capable of recording even very small earthquakes in Southern California, and geophysicist Charles Richter devised a formula (now referred to as the Richter Scale) for measuring the size of those quakes. Later, Richter and geophysicist Beno Gutenberg would apply the formula to earthquakes throughout the world.

The Recommended Daily Adult Requirement

Henry Borsook The RDA of vitamins A, B, C, and D grew out of work carried out at Caltech in the 1930s and 40s by biologist Henry Borsook. His research led the government to establish the Recommended Daily Requirements for Human Nutrition.

The Smallest Building Blocks of Matter

Murray Gell-Mann In the early 1960s, Caltech physicist Murray Gell-Mann determined that protons and neutrons, long considered the smallest building blocks of matter, are made up of even smaller particles, which he named quarks. Quarks were not discovered in the laboratory but at Gell-Mann's blackboard; their existence has since been verified experimentally. Their discovery opened up new avenues of research in subatomic physics, clarified the nature of the "strong force" that holds protons and neutrons together in the atomic nucleus, and pointed the way to a better understanding of what occurred in the first instants of the Big Bang, the explosion that gave birth to the universe. Gell-Mann received the Nobel Prize in 1969.
Left Brain/Right Brain
Roger Sperry It was at Caltech that psychobiologist Roger Sperry discovered that the left and right hemispheres of the brain are specialized for different capacities: the left brain for verbal thinking and language; and the right brain for spatial-visual thought. His work has had an incalculable impact in fields ranging from education to behavioral psychology to neurophysiology. Sperry was awarded the Nobel Prize in 1981.

The Dawn of the Aerospace Age

Theodore Von Karman The principles of modern aviation and jet flight grew out of work carried on at Caltech by Theodore von Karman, the head of Caltech's Graduate Aeronautical Laboratory (GALCIT) during the 1930s. At GALCIT, von Karman and his students developed the principles of airplane design and flight that helped get the aircraft industry off the ground and turned southern California into the aircraft capital of the world. In the mid-1930s, off-campus experiments by several of von Karman's students led to the establishment in 1944 of the world-famous Jet Propulsion Laboratory, today the nerve center of America's robotic space program, including the Pioneer, Mariner, Voyager, Magellan, and Galileo missions to explore the solar system.

The Age of the Earth and the Perils of Lead

Clair Patterson That the earth has existed for 4.6 billion years was first determined in 1953 by Caltech geochemist Clair Patterson, through studies of the decay rate of lead isotopes in earth's oldest rocks. Patterson subsequently turned his attention from lead in rocks to lead pollution in the oceans and atmosphere. His demonstration that lead pollution from automobile exhaust had reached dangerously high levels, was a major factor in the U.S. government's decision to establish pollution controls within the auto industry. Patterson, and his determined and often lonely crusade against lead pollution, was made the basis of a fictional character in the Saul Bellow novel The Dean's December.

"We Are Starstuff"

Charles Lauritsen This phrase is a familiar one to viewers of the Carl Sagan series Cosmos and has much of its genesis in pioneering astrophysics research carried out for over three decades in Caltech's Kellogg Laboratory. There, a team of scientists, headed by the late Charles Lauritsen, demonstrated that nearly all the elements in the universe and in our bodies were originally cooked up inside stars. Kellogg physicist Willy Fowler was awarded the Nobel Prize in 1983 for his "studies of the nuclear reactions of importance in the formation of the chemical elements of the universe."

Probing the Secrets of the Universe

Maarten Schmidt A leading British astronomer, Martin Rees, summed up Caltech's record in astronomy in this way: "The universe of astronomy has no center but the universe of astronomers does. For years that center has been in Pasadena, California." Among Caltech's major contributions: in 1948, the first survey of the entire sky visible from the northern hemisphere, a survey that discovered thousands of new stars, galaxies and comets, and created an atlas of the heavens that astronomers the world over used for the next three decades. (A second Palomar sky survey was completed in 1999.) Palomar is also the home of the 200-inch Hale Telescope, for more than four decades the largest and most powerful optical telescope in the Western hemisphere. Some of the most significant astronomical discoveries of the past 40 years have been made with this instrument. It was also at Caltech, in 1964, that astronomer Maarten Schmidt determined that quasars, a puzzling class of cosmic objects, were the most powerful and distant objects in the universe. Since quasar light has been traveling for billions of years to reach Earth, Schmidt's discovery gave astronomers an unprecedented look at how the universe looked at a much younger period in its history, billions of years before the birth of the sun and its planets.

Animal Magnetism

Heinz Lowenstam In the 1960s, Caltech paleoecologist Heinz Lowenstam startled biologists and geologists alike with the discovery that many animals do what conventional science had considered impossible: they manufacture substances such as the iron-containing mineral magnetite within their bodies. Out of Lowenstam's work came the more recent finding that many migratory animals, including birds, bees, and whales, generate magnetite within their bodies and may owe their uncanny homing instincts to the presence of this "internal compass" that allows them to navigate by means of Earth's magnetic field.

Richard Feynman—a Caltech Institution

Richard Feynman The late Richard Feynman, one of the most brilliant theoretical physicists and original thinkers of the 20th century, epitomizes Caltech for many. Although Feynman's Nobel-prize winning research (he won in 1965) was largely completed before he came to Caltech in 1949, he continued to make discoveries at Caltech that many felt should have won him a second Nobel Prize. Beloved by students as a friend and teacher, Feynman also found time to perform year after year in Caltech student dramatic productions. A drummer and artist as well as a physicist and actor, in 1985 he also turned popular author and published an irreverent memoir, "Surely You're Joking, Mr. Feynman," that spent 14 weeks on the New York Times best-seller list. In 1986, he became known to an even larger audience through his participation, and his famous ice-water experiment, on the Presidential Commission investigating the explosion of the Space Shuttle Challenger. Commenting on Feynman's appointment to the commission, one Caltech colleague came as close as any to summing up the essential quality of his genius: "Do they realize," he wondered, "that Feynman asks questions and keeps asking them until he gets answers?"