Joel R. Primack (1945-2025)

Nancy Abrams, Joel's wife wrote on November 14:  "I am sorry to tell you that Joel died early this morning. He had survived pancreatic cancer for 8 years on immuno therapy drugs, but late last summer they just stopped working, and as autumn progressed he got sicker very quickly".

 

Joel came to Princeton from from Gardena (CA) High School, majored in physics, ate at Wilson, and was our class valedictorian. Joel's valedictory address, Science Cannot Give Us Values, warning of the misuse of science, is as relevant today as it was in 1966. Robert Oppenheimer, an honorary degree recipient at our graduation, praised Joel's speech to a New York Times reporter in this article the next day (see the bottom of the first column). Joel continued to tackle the fundamental problems by "going where the data is" and to advocate for science in the public interest throughout his long career.

 

Following Princeton, Joel earned his doctorate in Physics at Stanford in 1970 where Sidney Drell '46 was his dissertation advisor, was a junior member of Harvard's Society of Fellows for three years, and then joined the faculty at the University of California Santa Cruz. He retired as Distinguished Professor of Physics Emeritus although he continued his professional activities. Quoting from Joel's UCSC home page, he worked with numerous collaborators and specialized:

 

"in the formation and evolution of galaxies and the nature of the dark matter that makes up most of the matter in the universe. After helping to create what is now called the “Standard Model” of particle physics, Primack began working in cosmology in the late 1970s, and he became a leader in the new field of particle astrophysics.  His 1982 paper with Heinz Pagels was the first to propose that a natural candidate for the dark matter is the lightest supersymmetric particle. He is one of the principal originators and developers of the theory of Cold Dark Matter, which has become the basis for the standard modern theory of structure formation in the universe. With support from the National Science Foundation, NASA, and the Department of Energy, he has been using supercomputers to simulate and visualize the evolution of the universe and the formation of galaxies under various assumptions, and comparing the predictions of these theories to the latest observational data. He organized and led the University of California systemwide Center for High-Performance AstroComputing (UC-HiPACC) 2010-2015."

 

Added December 3, 2025: Joel's career and impact are summarized in UC Santa Cruz Memoriam which contains a link to Joel's 2017 talk at Google on galaxy formation.

 

Joel's professional achievements were widely recognized with significant professional awards which are summarized on the home page. Most recently, he was presented the American Academy of Science AAAS Abelson Prize. The citation covers Joel's scientific legacy and highlights his achievements in public service, advancing science in the public interest, and communicating to the public the significance and excitement of fundamental discoveries in which he played a significant role.

 

"In an era where science intersects with policy and public engagement, Joel Primack stands out for his diverse contributions. He played a pivotal role in establishing the AAAS Science and Technology Policy Fellowship program, which has empowered thousands of scientists to contribute to policy-making, creating a lasting impact on both individuals and the broader field of science policy.

 

"Primack has also mentored numerous students, many of whom have ventured into big tech and science policy. He underscores the importance of understanding one’s strengths and preferences early in a scientific career, and recognizing when a problem is ripe for solution.

 

"In 1988, Primack led the Federation of American Scientists program on space nuclear reactor arms control and helped stop the launching of Soviet reactor-powered satellites. In 2004, as a member of the APS Panel on Public Affairs, he organized and chaired the committee that wrote a critical APS report on President Bush’s Vision for Space Exploration.

 

"Primack also started the program on Science and Human Rights at AAAS. In 1995, he was made a Fellow of the AAAS “for pioneering efforts in the establishment of the AAAS Congressional Science Fellows Program and for dedication to expanding the use of science in policy-making throughout government.” He chaired the AAAS Committee on Science, Ethics, and Religion from 2000 to 2002.  He also co-authored a book about the relationship between science and government, and two books about the meaning of the new cosmology."

 

He was a dedicated teacher and mentor for his students, both graduate and undergraduate, many of whom went on to distinguished careers of their own. Joel and his wife Nancy also wished to share the excitement and implications of the latest discoveries in physics and cosmology and coauthored two books for the general reader, The View from the Center of the Universe: Discovering our Extraordinary Place in the Cosmos and The New Universe and the Human Future: How a Shared Cosmology Could Transform the World. Their 18-minute 2011 TEDx Talk Changing The World Through A Shared Cosmology addresses these ideas.

 

Joel took the time to speak to the Princeton community at reunions and to the class at a San Francisco luncheon (State of the Universe Report slides), a June 1, 2019 Locomotive Award presentation (scroll down; the awards are chronological. Here's the Locomotive Award citation), and in a November 17, 2021 '66 Tiger Talk, Adventures in Science and Politics (login required). His Tiger Talk covers all aspects of Joel's life and career. Joel explains how he went against advice and mixed science and politics, finding the result enriching and fulfilling. He ably communicated the science to the rest of us and used vivid and imaginative images to explain such findings as the fact that we can only see about 5% of what's out there. Joel also highlighted the role that Princetonians have played in developing modern cosmology from our time on the campus and over the ensuing decades. The Tiger Talk covers Joel's work for disarmament, acquaintance with figures who inspired him such as Andrei Sakharov, and work for science in the public interest. You'll also learn about the first good thing Joel heard about uranium and what's good about it.

Joel Explaining it to the rest of us at Terhune Orchards Locomotive Award ceremony

Nassau Herald

2025 Greetings from Nancy and Joel: Samara’s with husband Patrick, a Hollywood screenwriter. Their son Wilder loves school, reading, Legos, and especially soccer.

Tributes and Memories

Ned Groth:

Ned wrote Me and Joel, Somewhere Near the Center of the Universe, a June 3, 2029 '66 Tiger Tale to tell the story of their friendship, careers, and public service.

 

Jeff Burt:

I am trying to process the loss of  Joel Primack and came across this autobiographic piece by Joel (Joel's scientific biography, part of his UCSC home page). It is pretty up to date. Just scanning it quickly takes my breath away. If this were anyone else but Joel, I would feel the writer was overly impressed with his accomplishment and self importance.
 

But as you know well, this is 100 percent true. It is not a reflection of arrogance - but rather an incredible lifetime of achievement. Joel was a phenomenon and simply being in his presence was an honor and blessing. We will miss our valedictorian greatly!!

 

Jon Holman:

I knew Joel slightly back in campus days, but that's all. I was mortal and he was, well, a lot smarter than I. I aspired to someday take some classes he skipped as a freshman (math, not physics. I didn't even aspire to physics).
 
I encountered him again at a wedding in 2016. My niece Marsea (actually Diana's niece but I've adopted her) was getting married, and Marsea is a close friend of Joel's wife Nancy Abrams. I saw Joel's name on the wedding attendee list and found him. He was, as always, charming and friendly, even pretending that he remembered me.
 
Then Joel began to endure years of pancreatic cancer. Stage 1, Whipple surgery, seemingly OK, then suddenly stage 4, then a miraculous immunotherapy trial which worked for years until it didn't. During that whole time he engaged more fully with our class and with Princeton. He was going to speak about dark matter to our San Francisco lunch group, but his plane was late, so we rescheduled it. At our 53rd Reunion he made it back to Princeton and we gave him our Locomotive Award, which you can read about separately on our website. He was planning to come to our 60th.
 
You can read about his many accomplishments elsewhere on these pages. Joel was a renowned physicist and an extraordinary connecting point between scientists and the broader world, including government. He received many awards. He was a great raconteur; he brought down the house with his story about how a senior Caltech professor (or maybe head of admissions), a Princetonian, convinced him to go to Princeton rather than Caltech even though Joel had figured for years as a Southern Californian that he would go to Caltech. The reason: Joel was just as interested in the humanities as in science.
 
Joel was proud of his many accomplishments, but I never heard him mention that he was our valedictorian. The only words of praise on which he was unwavering were for Nancy, his collaborator and wife and very accomplished in her own right, his daughter Samara, and his grandson Wilder. Just read Samara's words on this page and you'll understand Joel well.
 

It's always sad when a classmate dies. But we all thought Joel was cured, and indeed for several years he really seemed to be. We thought he had beaten a disease that had killed his father and brother at much younger ages. So it's doubly painful that a seeming miracle was maybe that, but not enough.

 

Len Hirsh:

Joel showed me, without any intention of doing so , that I should give up my idea of pursuing a career in academic physics.  As I was struggling with senior math courses of mysterious complexity, Joel was reading the material as if it were a comic book. He was quite shy in those days about his abilities, but impressed us all.  He will be missed by all who knew him.

 

Tom Adams:

We had the privilege of taking Honors Math with Joel, who was the brilliant physicist/philosopher of our time. This was the class that convinced me, JP Godich, and the late Jack Cohen that we were not meant to be math majors. All of us attended Prof. Washnitzer’s seminar-style lectures on differential geometry and topology. Joel sat in the front row and asked deeply insightful questions. Each week, JP, Jack, and I, and a couple of other guys, met without Joel as a late-night support group in an empty classroom in McCosh to work out the problem set that was due the next morning. Our papers always came back with the errors marked in red. Instead of showing corrections, the papers always had the same notation at the top, “See Mr. Primack’s paper.” Joel’s homework assignments were so perfect that they became the answer key. We were in the presence of genius. He fulfilled his promise in his career. His passing is a great loss.

 

Fred Forster:

As a physics major at Princeton, I know “of” Joel Primack—but a Venn diagram displaying our mutual, contemporaneous experiences would be narrow indeed. While I researched how Cadmium Sulfide solar cells worked, his focus was eventually to determine how the Cosmos worked—a  life well lived at a very different, infinite scale.
 

However, I did follow his career closely to witness the amazing insights he surfaced to help us comprehend…well, like everything.  I recommend to all of us to watch a TED talk from 14 years ago, “Changing the World Through a Shared Cosmology”. Joel and his wife, Nancy Ellen Abrams, an equally brilliant philosopher, focused on the interfaces among history, philosophy and science, and connected the dots.  I just watched it for the 3rd time and the call for us to understand just where we fit into the Cosmos and the nature of our responsibilities to deal with global issues was palpable.

 

Jeff Weiss:

Aside from being the '66 Valedictorian, speaking before J. Robert Oppenheimer at the '66 Graduation, Joel truly played a major role in the current leading physics and cosmological model of the universe; i.e., Lambda-Cold-Dark-Matter (although that model has been taking some major hits here and there from the Webb Telescope and latest European satellites in recent years). I attach a photo of Joel speaking to the SF Luncheon group at the Delancey Street Restaurant on the Embarcadero in 2019 -- at an earlier time when we had ~30 attendees and were given a private room for our '66 lunches there. It shows myself, Joel and Gib Hentschke. As a physics major, it was a privilege to have been the same Princeton class with him.

 

Samara Bay '02, Joel's daughter:

"It's like the great library of Alexandria burned a second time." My mom said this the morning my dad died, this week.

My dad was a great man. In mind, in kindness. A world-renowned astrophysicist known for his hand in Dark Matter -- a theory he and colleagues offered in the early 80s that remains the best understanding for what makes up 90-something % of the universe. And renowned among those who worked with him, knew him, and loved him, for how consistently he fought for women in science, for the responsibility scientists have to society and the public good, and for truth.

He spent his last good day this week writing 8 letters of recommendation for his former students. He felt they relied on him, and also felt it his sacred duty to leverage his power.

He read voraciously and across disciplines. I used to call his vast knowledge a "murky abyss" when I was in high school and wrote in my application to Princeton (where he was the valedictorian of 1966) that I wanted one of those murky abysses of my own. He was interested in everything and had a twinkle in his eye when he'd learn something new. Always confident in his brilliance; never attached to certainty.

He gave me incredible genetics (the big brain! The impossibly youthful skin!) but more than that he gave me incredible generosity.

I'm an only child and he made me feel as special as the universe. He may have even liked me more. Proud of me and everyone (everyone!) knew it. Cared about my ideas at the dinner table. Made it clear in word and action that he was a true feminist. A fervent (and financial!) supporter of my career as an artist. An endlessly curious ear for my moves since then, always sending links to pieces he thought I should read or people who should appreciate my work.

I have spent my life trying to spread the kind of permission my parents gave me.

My mom and I are heartbroken and grateful. He survived pancreatic cancer for nearly 8 years, a total medical miracle (due in part to luck and in part to his science-minded drive to be his own experiment to the end, to have a hand in curing this thing if at all possible). We're planning a memorial in the new year.

For now, going for soft grief. Just love. Just so much love.

Joel Primack, you are immortal.

 

Robert L. Jaffe '68

 

Joel was a friend and collaborator for almost 60 years. We worked intensely together creating SWOPSI (Stanford Workshops on Political and Social Issues) for several years as graduate students at Stanford.  Curiously, Joel and I had both come from Jewish backgrounds, both been undergraduate physics majors at Princeton, and both were valedictorians of our classes (’66 for Joel, ’68 for me). The goals of SWOPSI resonated with our vision the of university “in the Nation’s service". Joel’s life was a model of how scientists can integrate fundamental research with service to humankind.

 

Frank N. von Hippel, Princeton Professor of Public and International Affairs emeritus

 

Joel made a difference in a number of areas. He also had a good marriage and Nancy and he raised a creative daughter who is carrying on and raising the next generation. In short, a good life!

 
The area where I have the most to contribute to memorializing Joel would relate to the creation of the Congressional Science Fellowships, which Joel launched, as a post-doc influencing the American Physical Society and the American Association for the Advancement of Sciences – although I don’t know the details of how Joel did so and who facilitated that effort.
 
I believe that Joel also had a key role in getting the American Physical Society Summer Studies going.  He certainly got me involved in running a summer study on summer studies(!) and then the following year in organizing the Reactor Safety Study, which facilitated my transition from pure to what I call “policy physics.” 
 
We also co-authored Advice and Dissent: Scientists in the Political Arena, which prepared me for my own career in the policy arena and (we were told much later) resulted in a reform of the way that the National Academy of Sciences National Research Council studies are done: making them more independent of the influence of their sponsors. 
 
So, despite the fact that I was older and more senior: a starting Assistant Professor when I met Joel as a first-year graduate student at Stanford, he had more influence shaping my career than I did in shaping his. 
 

And, of course, in the background was the Vietnam War, to which a whole generation was reacting and which led many of us to focus on public policy who otherwise would have continued in more conventional careers.  I hope the uprisings today have a similar positive effect on the generation that is currently developing.  As a result of the information-technology revolution, they live in a very different and more artificial world than the one we grew up in, however, and the paths they create will be very different from ours.

 

 

Tributes from Joel's students and others who knew him:

Joel was a dedicated teacher who was very supportive of his students. The Neptune Society obituary contains student tributes.

If you have photos or memories that you wish to share, please send them to the '66 Memorial Team (66_MemorialTeam@tiger1966.org). We will add them to this page.