Berni J. Alder

Berni J. Alder of El Cerrito, California died on September 7, 2020 at the age of 94 from complications of heart failure. Berni was a scientist of great influence and international distinction, who was among the 1950s pioneers of using computer simulation to model the behavior of materials at the atomic level. He was especially known for adapting Monte Carlo techniques to create the field of molecular dynamics and solve problems in quantum mechanics. Successor techniques are applied today to problems ranging from molecular biology to financial planning to predicting elections. For this work Alder won many honors: the 2008 President’s Medal of Science awarded by Pres. Barack Obama, the Boltzmann Medal, the Guggenheim Fellowship, and membership in the National Academy of Sciences and the American Academy of Arts & Sciences. The “Berni J. Alder Prize” is awarded in his honor every three years by the Centre Européen de Calcul Atomique et Moléculaire.

Berni Alder was born to Ludwig Adler and Otillie née Gottschalk in Duisburg, Germany on September 9, 1925. In 1933, as soon as the Nazi regime rose to power, Berni, his parents, elder brother Henry, and twin brother Charles fled to Zurich, Switzerland. In 1941 they emigrated to the U.S. to settle in Berkeley, California. Alder attended one year at Berkeley High School, then enrolled in UC-Berkeley. His studies were interrupted in 1944, when he was drafted into the U.S. Navy. He became a U.S. citizen while serving as a radar technician coordinating allied communications in the Pacific theatre. When the war ended, he returned to Berkeley to complete his degree.

While working towards his PhD from Caltech in 1953, Alder came to the attention of Edward Teller who was impressed that Alder had independently hit upon the Monte Carlo technique, although his thesis advisor had dissuaded him from publishing his idea. Teller hired him to work as one of the earliest employees at Lawrence Livermore National Labs, where he continued for the next 66 years, well past his official retirement, stopping only when Covid-19 closed the facilities. He also held joint appointments at UCBerkeley and UC-Davis and mentored several generations of graduate students and postdoctoral fellows.

Berni was a patriot who served his adopted homeland and international science alike. His highest ideal was to make “a contribution” to the collective project of scientific knowledge. He was an intensely curious person whose interests ranged from atoms to people—and everything in between. He took a sensual delight in the world: skiing and hiking in the Alps as a boy in Switzerland and later in the Sierras; travelling widely to conferences, usually as a honored guest; taking in ruins, museums, theater, and opera; and transplanting his family for sabbaticals to Israel, Rome, Amsterdam, and Paris. Berni loved to talk to young people, asking questions so direct they actually answered them. He was a generous host who loved dining with friends and family, eating his way through the best restaurants in France and California.

Berni leaves behind his beloved wife, Esther née Berger, and their three children and families: his son Prof. Ken Alder, his wife Dr. Bronwyn Rae, and their daughter Dr. Madeleine Alder; his son Rabbi Daniel Alder, his wife Rebecca Kryspin Alder and their children, Gabrielle and Yonatan; and his daughter Prof. Janet Alder Suss, her husband Eric Suss and their two daughters, Rachel and Nina. Berni was predeceased earlier this year by his twin, Charles, his best friend and constant companion of 94 years; leaving behind Charles’ daughter, Stephanie and her daughter Joanna and her family. Berni was also predeceased by his older brother, Henry, leaving behind his son, Larry and his family, Janice, Allison, and Cate. He was also especially close to his wife’s family in Toronto, notably the families of Ralph and Susan Berger, and their children Eric and Esther and their families; and David and Eileen Berger, and their sons Michael, Avi, Josh, and Aron, along with their families.

A private funeral service was held on Sept. 10. Donations may be made in his honor to either the UC-Berkeley Chemistry Department https://chemistry. berkeley.edu/giving or the Mazon hunger relief charity www.mazon.org.