Nobel Laureate in Physics visits campus

by Ruben Gallardo | 5/15/18 2:30am

On May 9, Dartmouth welcomed Nobel Laureate in Physics Jerome Friedman to campus for the second time for a public lecture entitled “Are We Really Made of Quarks?” to a packed audience in Dartmouth Hall. In addition to the lecture, Friedman also met with three students from the Women in Science Project and visited Physics 72, “Introductory Particle Physics” earlier in the day.

When he was a high school student, Friedman received a scholarship from the Art Institute of Chicago Museum School, but after reading the book “Relativity: The Special and the General Theory” by Albert Einstein he decided to pursue an undergraduate degree in physics instead at the University of Chicago. In 1956, he received a doctorate degree in physics from the University of Chicago and in 1960 he joined the physics faculty at the Massachusetts Institute of Technology, where he is currently a professor of physics emeritus.

In 1990, Friedman was jointly awarded the Nobel Prize in Physics with Henry Kendall and Richard Taylor for their science experiments, which were “of essential importance for the development of the quark model in particle physics,” according to the Nobel Prize website. These experiments focused on inelastic electron scattering from the proton and neutron and provided evidence of the “quark sub-structure of the nucleon.”

During his lecture, Friedman said that after Ernest Rutherford’s 1919 discovery of the proton and James Chadwick’s 1932 discovery of the neutron, scientists wondered if these two particles were either fundamental — particles with no substructure — or composed of other particles.

In 1964, Murray Gell-Mann and George Zweig proposed the quark model, which postulated that protons, neutrons and other particles are composed of smaller constituents.

Friedman’s team of investigators from MIT and Stanford University then conducted experiments from 1967 to around 1975 to search for these quarks in the proton using the Stanford Linear Accelerator Center, he said during the lecture.

“We are made of three different things: up quarks, down quarks and electrons,” Friedman said during the lecture. “All atomic matter is made of those three objects in different combinations.”

Physics professor Timothy Smith, who currently teaches “Introductory Particle Physics,” said he thinks that Friedman tried to emphasize in his lecture that although physicists now believe in the quark model, the evidence that proved this theory is very different than the evidence used to prove the existence of other particles.

Friedman showed optimism when he was asked about the future and responded that he believes future generations will figure out answers to the questions that remain unanswered in particle physics, according to Smith. Margaret Hubble ’21 attended Friedman’s lecture and also had the opportunity to meet Friedman personally because of her position as a WISP research assistant for physics professor Devin Walker. Hubble said she found the lecture to be very informative and that she appreciated Friedman’s inquisitiveness during the question and answer session.

“There was always more that he was looking for [during the question and answer session],” Hubble said. “He ended on questions he had about particles and physics. That’s always something that has meant a lot to me because [in physics] there is always one more step and something else we don’t know.”

Megan Ungerman ’21, who is also Walker’s research assistant, said that she, along with her fellow research assistants and WISP members Hubble and Amari Young ’21, had the opportunity to eat lunch with Friedman at King Arthur Flour in Norwich, Vermont.

“[Friedman] talked about where he was born, how he was raised in Chicago and how he got into physics,” Ungerman said. “He [also talked about] these experiments that people didn’t want him to be doing … but then he [provided direct evidence for] the quark [model].”

Smith added that he thinks Dartmouth students benefit from meeting leaders in their fields of study because they can see that these important figures are also real people.

“Bringing people like Friedman gives students a chance … to have a connection with real applications of where their careers could go if they want them to,” Hubble said. “[It also allows students] to understand the larger implications of why we are here [at Dartmouth] learning.”