Roberto Peccei

Roberto Peccei (1942-2020) was a brilliant scientist, a natural leader, a thoughtful colleague, and a special friend. During his distinguished career at UCLA, he has served as a department Chair (1989-1993), Dean of Physical Sciences (1993-2001), and Vice Chancellor for Research (2000-2010), overseeing a significant expansion of UCLA research efforts and the advent of major institutes on campus.

Roberto Peccei was born in Torino, Italy in 1942. He was a son of Aurelio Peccei, an Italian industrialist and philanthropist, who was a member of the anti-fascist movement and the resistance during the World War II, then moved to Argentina to oversee Fiat operations in Latin America, and later founded the Club of Rome with the goal of addressing the multiple crises facing humanity and the planet. Roberto completed his secondary education in Argentina and came to the United States in 1958 as a student. He obtained a B.S. from MIT in 1962, M.S. from NYU in 1964, and a Ph.D. from the MIT Center for Theoretical Physics in 1969. After a postdoctoral appointment at the University of Washington, Dr. Peccei joined the faculty at Stanford University Physics Department (1971-1978), then moved to Max Planck Institute for Physics and Astrophysics in Munich, Germany (1978-1984), and later became the Head of Theory Group at one of the largest European laboratories, DESY in Hamburg (1987-1989). Professor Peccei joined UCLA in 1989, where he conducted research in theoretical physics and served in many administrative positions, including Vice Chancellor for Research. Professor Peccei had a very significant global presence; his service extended well beyond UCLA and included service on many national and international committees on science, as well as the Executive Committee of the Club or Rome.

One of the most famous scientific contributions, and an example of Roberto Peccei’s brilliant thinking is the celebrated Peccei-Quinn symmetry, proposed in collaboration with Helen Quinn. Interactions of elementary particles, as well as the very existence of matter in the universe depend on how different the world would be under the hypothetical action of flipping all particle charges and reflecting the world in a mirror. This mathematical transformation, called “CP” is closely related to flipping the arrow of time. Some physical processes are not invariant with respect to such a transformation, which, remarkably, allows for the dominance of matter over antimatter in the universe. However, if one considers only the strong interactions, which hold the nuclei together, the CP transformation leaves them invariant even though it requires an apparent conspiracy of some seemingly unrelated parameters (the vacuum “theta angle” and a phase coming from the mass parameters of quarks). Peccei and Quinn proposed a brilliant explanation based on a new symmetry of nature. This symmetry implies, in particular, the existence of a new particle which has not yet been discovered, but which has the potential to account for cosmological dark matter, that is, for most of the matter in the universe. Peccei-Quinn symmetry emerges in other areas of physics and has been studied by many scientists in a variety of contexts.

Roberto Peccei’s seminal and groundbreaking contributions have been recognized by numerous prizes and awards. He was particularly happy to receive the J.J. Sakurai Prize for Theoretical Particle Physics awarded by the American Physical Society, of which he was a long-standing member and a Fellow, as well as Chair of Division of Particles and Fields. Roberto Peccei was also elected a Fellow of American Association for the Advancement of Science and a Fellow of Institute of Physics, UK. He was awarded the order of Commendatore in Italy, and a number of honorary professorships and lectureships. In 2016, Roberto Peccei became a member of the American Academy of Arts and Sciences.

Professor Peccei was a passionate communicator of science, who enjoyed teaching graduate and undergraduate students at UCLA. In recent years, his course on the Physics of Energy served as a source of much needed knowledge and inspiration for his students and colleagues.

The memory of Roberto Peccei will continue to inspire his colleagues, postdocs and students.

Roberto Peccei is survived by his wife Jocelyn and their children Alessandra and Aurelio. In lieu of flowers, the family encourages friends of Roberto to make donations in his honor to UCLA Physics and Astronomy, as well as Parkinson’s Disease research at UCLA.


    Cards for the family may be sent to:

  • Department Chair
    UCLA Dept. of Physics & Astronomy MS154705
    475 Portola Plaza
    Los Angeles, CA 90095-1547

Personal Comments

Bill Gelbart added at 2020-07-04 12:13:59
I met Roberto when he first came to UCLA over 30 years ago, and he has been one of my favorite colleagues ever since: from our work together in the early days of the California NanoSystems Institute; from my years as Chair of my Department when he was Dean of the Physical Sciences Division; and - most importantly - from our frequent discussions about science, people, and philosophy. Of the many stories I could tell, I mention here only one. After feeling inspired (but also greatly humbled) by Eugene Wigner`s profound essay on "The Unreasonable Effectiveness of Mathematics in the Natural Sciences", I consulted Roberto for help, and with his modesty, generosity, and sense of humor he somehow succeeded in assuring me that he understood little more of the essay than I did. I will sorely miss these encounters with him, and strongly cherish my many wonderful memories of him.
William Bardeen added at 2020-07-02 05:48:40
Roberto Peccei was a remarkable leader and an outstanding scientist as well as dear friend and colleague. His legacy will remain with us through his many accomplishments and through the colleagues and students whose lives he has changed forever.
Frank Wilczek added at 2020-06-17 06:18:03
Roberto made the world a better place while he was with us. He exuded warmth, enthusiasm, and generosity. His contributions to the substance of science and to its community live on.
pakvasa added at 2020-06-16 17:03:23
"I recall the extreme kindness and friendship and humor with which all interactions with him were always present. I first met him when he was at the MPI in munich and I was visiting from CERN. When I first arrived, I told him about an earlier visit, when i felt insulted anot welcome by the reception by Duerr et .. and Roberto assured me cordially of how I was most welcome, and sureenuf, I had a wonderful time. My next memorable encounter with Roberto was in 2001.I was returning from a stay at Dubrovnik going back home. I happened to by flying on sept 1, 2001. The flight was diverted to Calgary and we had to spend 2 nights in a school. On the third day, we were allowed to resume our journey. As we were collecting our baggagr and shuffling in a very very long queue very slowly. At one point, I heard someone shouting my name! I was very surprised and turned around, and saw Roberto approaching me from far away! When he reached me and we greeted each other, he said that he was sure that there woulld be at least one physicist in this crowd. We then had a pleasent chat, and I learnt that he and his wife were returning from a vacation."
Jose Bernabeu added at 2020-06-16 04:02:26
"I met Roberto for the first time at CERN in the 70`s and enjoyed enlightening discussions. His friendship has been a pleasure and an honor. He leaves a legacy of influential scientific ideas, leader of excellent research groups and best person if possible. We will miss him. His memory will remain with us. My deepest condoleances to his family and colleagues at UCLA."
Kenichiro Aoki added at 2020-06-11 02:03:52
I was one of the first postdocs (of the many) when Roberto came to UCLA, in 1989. He was very friendly, welcoming, and quite supportive of those around him, including those starting out, like me. The four years I spent there were formative to me in physics, as well as in my life. Roberto made the environment lively, friendly, and productive, both as the Department Chair, and as the head of the research group. His memory will live on amongst us, those people he touched.
Andrea Johnson added at 2020-06-10 22:18:07
I was so saddened to hear of Roberto's passing. I knew him for most of the 25 years I worked at UCLA, and he was my boss's boss at the time I retired. Always polite. Always upbeat and professional. He was one of a kind. I applied to be his assistant when he was the Vice Chancellor. He personally called me to tell me that I had not gotten the job. Who does that? Roberto. All class.
David London added at 2020-06-10 11:17:56
"In 1987 I went to DESY as a postdoc. Roberto was my supervisor, but he quickly became a mentor. In working with him on problems in B physics, his ability to intuit the answers was extraordinary. From him I learned that, while it's important to know how to do calculations, the most important thing is a deep understanding of the physics involved. I used to say that if Roberto said a particular physics point was true, it almost certainly was, even if we didn't have a proof. He was also extraordinarily kind. While I was at DESY, my mother passed away, and Roberto & Jocelyn invited my father and me over for dinner. A small gesture, to be sure, but one completely in line with Roberto's character. I will miss him."
Ahmed Ali added at 2020-06-10 09:53:38
"It is with deep sorrow and sense of personal loss that I and my wife (Lubov Vassilevskaya) read the notice of Roberto's death. We came to know Roberto in different ways: She heard his lectures at the Erice summer school and later worked on the axion physics, and I got to know him as he joined the theoretical physics group at DESY, which he headed for five years. Roberto was a born leader - very inspiring and highly supportive. Personally, I owe him a lot as hehelped me out of a difficult situation related to my work. in Roberto, we have lost a true friend and a great physicist. "
Brian Hill added at 2020-06-10 01:54:57
Roberto's collegiality and positivity established a great environment for all those around him. He was larger than life in his good will and energy. I am grateful to have been among those in his orbit for a few years.
Xinmin Zhang added at 2020-06-10 01:22:06
I came to the theory group of DESY and studied with Roberto in the summer of 1987. One year later, Roberto took me and Boris Kastening to UCLA. After I received my Ph.D with Roberto in the summer of 1991, and two postdocs in US, I came back to China and worked in the Institute of High Energy Physics since then. For the past more than thirty years Roberto had a tremendous influence in my scientific careers. The last time I met Roberto is when I visited UCLA in the last September. Still like a student I reported to him what I am doing in China to build a CMB polarization telescope in Tibet to search for the Primordial Gravitational wave, and listened to his instructions. Thank you, Roberto! My family and I will miss him greatly.
Reinhold Ruckl added at 2020-06-10 01:20:56
"With Roberto we have lost a wonderful person and a distinguished scientist, open-minded, creative, committed, generous, kind and always ready to help. His ideas and contributions have lasting influence on particle physics and beyond. He built up strong research groups and put the scientific carees of many students and postdocs on a successful track. I met Roberto for the first time when he joined the MPI at Munich. Since then I had the great privilege to interact with him in many ways until these days. He was an encouraging teacher, an inspiring collaborator, a valuable advisor, and became a good friend. I owe Roberto a lot. But not only his achievements in physics and his service to academic institutions, also his devotion to social matters, for example, as a member of the Club of Rome, are truly exceptional. To be around him was always exciting. He is unforgettable and will be sorely missed."
Zvi Bern added at 2020-06-09 22:09:04
"I was greatly saddened to learn of the passing of my good friend and mentor. Whatever good judgment and optimism I have I picked up mostly from him. A spectacularly great physicist and teacher who understood that theoretical physics is not just about equations but is a thoroughly human activity. A great loss for the physics community and for UCLA. A true mensch. "
Wolfgang Lerche added at 2020-06-09 12:25:02
Roberto was my PhD advisor and brought me on the right track. At the time, he was almost the soul of the MPI, he was everywhere, always in full action, be it for his 80 hours course on quantum field theory, or for his humor and laughter on the floor. He shaped quite a number of us students. I will never forget what he has been doing for me and the group there.
Claudio Pellegrini added at 2020-06-09 11:29:30
I met Roberto when I joined UCLA in the Fall 1989, a short time after he had moved there. He was very friendly, supportive and helped me in many important ways to start my new program and everything that I did in the following years. Roberto has been a constant point of reference for me during all my time at UCLA and later, after I retired, as he has been for many other people. I am so sad to think that I will not talk to him the next time I visit the department. It is a big loss for physics, UCLA and for me and Maria Grazia.
Mike Cornwall added at 2020-06-09 11:16:55
Roberto and Jocelyn were good friends, whom we saw less of than we would have liked in later years. When he first came to UCLA, after a couple of months I had the temerity to suggest that he become the new department chairman. Up to the appearance of Roberto, our theoretical physics funding had been only NSF. It seems that there was an informal agreement between NSF and DOE that UCLA was NSF's bailiwick. However, Roberto and I made a personal visit to DOE and convinced them that Roberto deserved funding for himself and some junior people, and DOE responded handsomely to the prospects laid out by Roberto. His chairmanship was but the start of a long and very productive career in leadership at UCLA, as well as in physics. Although in all these years I only wrote one paper jointly with Roberto (on a project initiated by Alex Kusenko), I very much enjoyed working with his postdocs, notably Duncan Morris. Roberto had the bad luck to be hit by a string of serious health issues, but he worked hard and fruitfully in spite of these handicaps, I will miss him a great deal.
Wilfried Buchmuller added at 2020-06-08 16:14:32
The two years as a postdoc in Roberto's group at the MPI in Munich were a special time in my life. The intensity of discussions and the feeling to embark on new unexplored directions were very exciting. Moreover, discussions beyond physics were at least equally interesting. With his open and friendly personality Roberto created an atmosphere that will be remembered and that will last among his collaborators and friends.
Claudio Dib added at 2020-06-08 11:27:21
Roberto has been one of the most influential persons in my life in many ways. While I was a postdoc at UCLA Roberto provided such a wonderful environment to work and interact with people that became my friends until today. His insight help me learn physics for sure, but also showed me how a good scientist and professor should be as a whole. His capacity as a leader and organizer I always admire and keep in my thoughts as a reference for myself. But most of all I feel very fortunate for the opportunity I had of sharing time with him, such a kind, generous person he always was. My wife Susanne and I accompany Jocelyn and family in our thoughts. Roberto will be greatly missed by us.
Tao Han added at 2020-06-08 07:07:25
I was privileged to have worked with Roberto on one project in 1995, together with his former student Xinmin Zhang, who is now a leading physicist in China working on physical cosmology. The top-quark was newly discovered by then at the Fermilab Tevatron, with a surprisingly large mass. Roberto pointed out to us that the top will inevitably decay to a charm-quark plus a Z-boson via a Flavor-Changing-Neutral-Current process, which will be admittedly very rare in the Standard Model, but could be sensitive to new physics. Our work laid out the ground for testing the t-c-Z interaction in the low-energy experiments and at the high energy colliders. The paper remains to be a standard reference in this topic. JoAnne Hewett and I extended this idea and proposed to look for the single top-quark production at e+e- colliders. I vividly remember that Roberto happened to chair the session in a conference where I was giving a talk on this topic. He was notably happy with his characteristic laughter and candid comments. Roberto's deep physics insight, his encouragement to junior colleagues, his magnetic personality left me permanent fond memories. Roberto will be dearly missed!
Santi Peris added at 2020-06-08 04:20:28
I joined the UCLA Physics Dept. in 1989 with a Fulbright fellowship. It was my first postdoc and Roberto had arrived not much earlier. Luckily for me, Roberto had gathered a very nice group of postdocs and we immediately hit it off. Coming from Europe, I had no idea about what life in L.A. would be like. Just as an example of Roberto's generosity, I remember he lent me his car for a full weekend (it was the first time for me to drive automatic...) so that I could be able to go to a car dealer and buy whatever old clunker I could find. In physics, he was also equally generous; always ready to try to help you out. I also remember how, after a full day of work in his office as Head of the Physics Dept. , he was ready to listen to postdocs like me who kept asking his secretary "Is Roberto available now?". It was quite amazing how quickly he was able to get into the discussion, grasp the main idea and make useful suggestions to be discussed the next day. His style of doing physics, and other things, was very contagious. After all these years, it still is.
Manfred Lindner added at 2020-06-08 02:32:37
Roberto was a great physicist with a very pleasant, generous and humorous character. I have great memories of the joint time in the early 1980s at MPI in Munich were we - a bunch of PhD students - really learned a lot from him. He was always open for questions or discussions and I still keep the notes from his excellent courses. Roberto certainly played a big role in the fact that quite a number of the students from that time hold now positions in science. Later we kept meeting at conferences and workshops and it was always a pleasure to discuss with him. Roberto contributed over time also in a very positive way to science administration and he supported various important initiatives, but his main interest always remained science. He was a great physicist and we will miss him.
Rogerio Rosenfeld added at 2020-06-07 17:38:19
"Roberto hired me for my first postdoc in 1990 as a World Laboratory fellow. He had a talent for getting funds and consequently there were many of us at UCLA. It was a wonderful time. We worked with Duncan Morris on the possibility of multi-(W,Z) production in high energy cosmic ray events motivated by a strongly interacting electroweak sector. It was a lot of fun to work with Roberto and Duncan. We were all touched by Roberto's kindness, generosity, good spirit, honesty and sharp intellect. I feel very fortunate to have had the opportunity to be around Roberto even if for a short period of time! "
Helen Quinn added at 2020-06-07 09:20:26
"Roberto was a wonderful person as well as being a great physicist. Working with him was such fun, and always interesting. He was the one who asked the right questions --and that is the most difficult thing to do in doing any science. He did not give up until we came to a good answer -- but his insistence was always cheerful and full of good suggestions for how to solve the problem, or good questions to set us thinking in a new direction.. We will all miss him. "
George Zoupanos added at 2020-07-07 02:13:06
"I feel very lucky that I met Roberto very early in my scientific life. During my frequent visits at MPI in Munich and later in the Theory-DESY, I had the opportunity to see from close and admire the great scientific atmosphere that Roberto was able to produce. A particular pleasure for me was Roberto's participation in the Corfu Meetings, where he came with Jocelyn. Similary I keep the best possible memories from Roberto's visit in our university in Athens, his 60th birthday in UCLA and our last meeting during a School in Mexico. Below is the dedication to Roberto's memory that you can find in our EISA (Corfu Institute homepage): Jun 1, 2020: It is with great sadness that we received the terrible news that Roberto Peccei has passed away. Roberto was an outstanding physicist a charismatic figure of our community, and a source of inspiration for several generations of theoretical physicists. Roberto has had great influence on theoretical physics by creating some of the most successful research groups in the world, first at the Max Planck Institute in Munich, then at DESY, where he headed the Theory Group, and finally at the UCLA where he also held the position of Vice Chancellor for Research. Among his many contributions to theoretical physics, the most famous is the solution of the strong CP problem done together with Helen Quinn, for which they were awarded the Sakurai Prize in 2013. Roberto participated in the early Corfu Meetings in the '80s as a lecturer. Roberto's presence in the early Corfu Schools and Workshops was of great importance for their success and in establishing them internationally. EISA mourns the passing of Roberto Peccei together with all his numerous friends, students and colleagues, while our thoughts are with his family and close friends to whom we would like to express our deepest condolences. "
Hidenori Sonoda added at 2020-06-07 00:10:44
I received the news of Roberto's premature passing with great sorrows. I was one of the young physicists hired by the UCLA particle theory group shortly after his arrival there. I still remember his phone call of job offer; his ringing voice was full of enthusiasm. His enthusiasm was contagious as people who met him personally all know. Working at UCLA under his umbrella, we were much encouraged and felt secure (however temporarily). I feel lucky to have known him. I would like to give my sincere condolences to Jocelyn whose interest and knowledge in Japanese culture made me feel at home.
Arkady Vainshtein added at 2020-06-06 14:32:40
My acquaintance with Roberto goes many years back in time. We did not meet often but at our every meeting he impressed me strongly. Besides his talents in physics, Roberto was a person with many valencies, a real leader. In spite of his numerous administrative duties he never lost his taste to physics and agility of his reactions to discussion of new ideas. I will miss him greatly.
Emily A. Carter added at 2020-06-06 12:53:20
I am filled with sadness in hearing this news. I experienced Roberto as a warm, genuine person of great integrity and passion for science. I knew him from my last tour of duty at UCLA, when I was a Professor of Chemistry from 1988-2004. I got to know him first when he was Dean of Physical Sciences and then after as Vice Chancellor for Research. I was so pleased that when I returned to UCLA last fall in my current role, I had the chance to reconnect with him at a UCLA event and then a couple of months ago, my husband and I ran into him and Jocelyn on the street. All four of us were masked, taking walks, during COVID19. We talked a bit then and I said I hoped to see them again soon. Roberto was beloved at UCLA. Certainly he was to me.
Valery Rubakov added at 2020-06-06 12:32:21
With great sorrow I heard that Roberto passed away. I have great memories of meetings with him in various places in the world, such as Moscow, DESY and Erice. He was a great physicist and outstandingly warm and pleasant character. He was very supportive of Russian theorists in chaotic 1990's when we had hard times out here -- this sort of solidarity is unforgettable. Really a great loss for the community, and for me personally.
Christof Wetterich added at 2020-06-06 07:08:20
Roberto was a great man, creative, with plenty of ideas, and caring for others. He took responsibility, on the small and the large. He not only made important contributions to physics - he also influenced many of us by building strong groups wherever he was. I learned a lot from him, not only in physics. His fine humor and his generous personality will not be forgotten.
Bob Cousins added at 2020-06-06 03:06:23
Roberto was my temporary assigned advisor when I arrived at Stanford in fall 1976. He and Jocelyn had a few of us new students to their house for dinner, about which we laughed for years. I took courses from him in 1977, including the period when he and Helen Quinn wrote their famous paper. He was a *very* popular, inspiring teacher, to the extent that students would imitate his catchy phrases and mannerisms. As it happened, we both spent most of our careers at UCLA. It was wonderful to have Roberto as a colleague and friend. His breadth of knowledge was a resource for all of us. I nearly always felt compelled to say yes to his requests to help him when he was our Chair and then Dean, and found myself in some interesting situations as a result. My wife and I are among the many who will miss him greatly.
Tsutomu Yanagida added at 2020-06-05 21:59:54
I will never forget the good days I had with Roberto in Munich. I would not have survived in Physics without his support. I would give my deepest sympathies. "
Marcela Carena and Carlos Wagner added at 2020-06-05 20:11:30
"We met Roberto back in January 1987, when we were graduate students at the Instituto Balseiro in Bariloche, Argentina, and we were attending the Swieca Summer School, in Sao Paulo. The encounter with him changed our lives. We were chatting with him during one of the warm evening breaks, when, after much hesitation, we decided to ask Roberto about the possibility of getting a postdoc at DESY after finishing our Ph.D. in Bariloche. With his usual charm, Roberto explained us that getting two postdoc positions at DESY was not going to be easy, but he could possibly get two student fellowships for us to pursue our Ph.D. in Hamburg. We were convinced that these were just empty words, but we did not know Roberto. When we went back to Bariloche two weeks later, there was a Telex from him, telling us that he was indeed offering us to go as graduate students to Hamburg University. We were extremely surprised, but seven months later we were in Hamburg, where we had a fantastic experience and we met plenty of wonderful people, in spite of the fact that we had to finish our Ph.D. in record time due to Roberto's departure to UCLA. Roberto was an amazing scientist and also an amazing person. He had a tremendous influence in our lives and in our scientific careers. We only wish we had had more time to interact with him in the last years. Thank you, Roberto ! With Love, Marcela Carena and Carlos Wagner "
Wick Haxton added at 2020-06-05 17:20:24
I will miss Roberto greatly. Perhaps the defining event of my graduate career was Roberto's advanced quantum/field theory course at Stanford. The problem sets were awesomely difficult and ambitious -- so much so that most of the class took incompletes in order to buy more time. Later it was a great treat, after becoming a professional physicist, to interact with him at meetings. He had such a large personality and cheerful approach to life. Such a loss.
Harry Nelson added at 2020-06-05 12:52:12
I believe I first met Roberto at CERN circa 1988, when I was working on e'/e with NA31. But it may have been earlier at SLAC when with some others I proposed an axion experiment. We visited a few times since then at UCSB and at UCLA. He was always warm and intensely curious about experimental issues, intuitive, and a great deal of fun to hang out with.