David Fryberger
Feb. 22, 1931-May 3, 2026
Palo Alto, California
David Fryberger, 95, died peacefully at his home in Palo Alto, California, on May 3, 2026, in the presence of his wife Betsy and son Mark. During his long career at the Stanford Linear Accelerator Center (1967 to 1998), David contributed significantly to its programs as an experimental physicist and later as a senior administrator and theorist. With a colleague in 1973, he devised a touch-panel screen that was a precursor to the modern touchscreen. He collaborated on the 1974 discovery of the J/psi particle, which revolutionized modern physics and earned SLAC a Nobel Prize. In later years, he pursued his own theoretical work postulating the existence of a subatomic particle that he named the vorton, a second solution to Maxwell’s symmetrized equations. During his remaining professional career and in retirement, David searched for manifestations or other evidence of either the vorton or its close relative, the magneticon (a magnetic monopole), to support his theory.
David was born in Duluth, Minnesota, on February 22, 1931. After his parents’ divorce, he spent summers in Duluth and winters in Daytona Beach, Florida. He attended Phillips Exeter Academy, won several science prizes, and then went on to Yale University, graduating with a degree in Electrical Engineering in 1953. In his last year at Yale, he met Betsy Geraghty, a freshman at Bryn Mawr College, through a chance encounter at a mutual family friend's apartment the day after Thanksgiving in New York City. Upon graduation, he joined the Navy and served for four years on active duty, followed by another 21 years in the Navy Reserve. As a flight navigator, he made hundreds of carrier landings. Throughout his military service, he corresponded with Betsy, and in January of 1957, they married in Chicago.
After a year on the Upper Peninsula of Michigan, the couple moved to Chicago in 1959. Betsy joined the staff of the Art Institute of Chicago and David worked as an electrical engineer at the Illinois Institute of Technology, from which he earned a master's degree in 1962. His never-ending yearning to understand how things worked led him to focus on physics. Admitted to the University of Chicago’s famous physics department, he received his PhD in 1967 and accepted a position at SLAC. He and Betsy settled in Palo Alto, where they made their home for more than 50 years.
In David’s search for evidence to verify his vorton theory, he traveled to Langmuir Laboratory for Atmospheric Research in New Mexico, Popocatepetl, Mexico, and to Hessdalen, Norway. He also collaborated on experiments with Jefferson Laboratory in Virginia. For the past 20 years, David has worked with Michael Sullivan on refining his theories and conducting experiments to detect his theorized particles; and Mike plans to continue. Outside of physics, David's interests were focused on two areas: singing and playing soccer. He sang in several church choruses and in the late 1980s, he joined the Russian chorus Slavyanka, singing in Bay Area concerts and traveling to Russia. An avid soccer player (he had been on Yale's varsity team), he played recreationally for 50 years and coached his son Mark's teams from first grade through high school. He was one of the founders of the SLACers soccer club in 1998, which continues to this day. He and Betsy also played tennis for many years and, in later years, avidly followed professional tennis on TV.
David enjoyed traveling, spending summer vacations in Duluth and New England with Betsy and Mark and his extended families. Her long career as a curator of prints and drawings and love of gardening took them to Europe where they visited historic churches, villas, gardens and museums. After sightseeing, they often enjoyed dinners at Michelin starred restaurants, with fine wines and dark chocolate desserts. In the Bay Area, they attended the San Francisco Opera for over 50 years and later were patrons of Music@Menlo.
David will be remembered for his patient, gentle soul, graciousness and dignity, the twinkle in his eye, and his kindness. Free of body, his spirit will continue to explore the fundamental building blocks of the cosmos that he spent his lifetime studying.
He is survived by his wife Betsy, son Mark and his wife Amanda, grandchildren Laura and John Patrick (Annalise), his two great-grandchildren Peyton and Weston, along with half-sisters Liz Pritchett and Mary Marcina, sister-in-law Helen Geraghty, his dear cousin Devon O'Brien, and many other cousins, nieces, and nephews.