Fred Gilman - Session II

Zierler:

This is David Zierler, oral historian for the American Institute of Physics. It is June 10th, 2020. It is my great pleasure to be here again with Professor Fred Gilman. Fred, thank you so much for joining me for round two of our talks. Thank you so much.

Gilman:

My pleasure as well. We will begin, I assume, where we left off.

Zierler:

Yeah. So where we left off — and we'll back it up a little bit — but just to sort of jog our memory, we left last time with the call you got to join SSC. And I know you want to provide some additional context about — I mean, my first question there was, what had you known about SSC before you got that call? And what was your state of awareness in terms of where SSC was headed, even before you decided to commit to the project?

Gilman:

So you might say it crept up on me —

Zierler:

[laugh]

Gilman:

— but it did not creep up in that I was well aware of what was going on in the community, and my choice to get involved in thinking about the physics potential was intentional. The summer workshop of the high energy community in 1982 at Snowmass Colorado is usually designated as the point at which the Super Collider concept was developed and began to be the goal of many US particle physicists. It was originally dubbed the desertron given the site that was imagined for a proton-proton collider with roughly 20 trillion electron volts per beam. As we touched on before, my personal involvement started with Jim Cronin organizing a workshop around the idea of not just having a proton-proton collider but having the option of a proton-antiproton collider. Part of that idea was to test for asymmetries between the behavior of matter and antimatter starting from an initial state that had equal amounts of matter and antimatter.

Zierler:

And was Cronin raising this issue as a direct result of his own work and the things that he was interested in at the time?

Gilman:

I think that one of the reasons he talked to me to give the theory summary was to assess the possibilities of measuring CP violation, a difference between the behavior of matter and antimatter, whose original observation led to Cronin and Fitch winning the Nobel Prize. To give that talk, I needed to be fully up to speed on the calculations that had been done up to that time for various processes that could lead to major discoveries, and not just those involving CP violation. A large group of theorists had already produced extensive calculations of both the production of new particles and the backgrounds from standard model processes. That was my intensive introduction to Super Collider physics in early 1984, and it led to attending the next Snowmass community workshop in the summer of 1984. I didn't appreciate before how much you accomplish by bringing people together for three weeks and being immersed day in and day out in thinking about the combination of the accelerator, the experiments, and the theoretical physics associated with the discovery potential of a future accelerator. Because we understood the strong and electroweak interactions in the standard model together with the structure functions giving the quark content of the proton, quantitative calculations of the rates for production of possible new particles were now possible. During Snowmass ’84, I was the co-chair of a group on electroweak interactions and Higgs bosons. One focus of that group was on Higgs bosons with “intermediate masses,” where intermediate mass meant greater than about 90 GeV, but smaller than where it would decay into two W bosons, which is about 160 GeV. Our report on discovering the Higgs boson in that mass range was gloomier than earlier because Rubbia’s group at CERN had just presented evidence for a top quark at 40 to 45 GeV, in which case the Higgs boson decays into a top quark and a top antiquark would swamp the other decay modes, in particular the decays into likely discovery modes like four charged leptons. I continued working with others on how to discover an intermediate mass Higgs at Snowmass ’86, while I co-led the group working on heavy quarks and CP violation at the SSC.

Zierler:

When was Rubbia disproved? When did that happen?

Gilman:

Within a couple of years. Large backgrounds in the signal region were found in subsequent analyses and further experiments at CERN did not confirm it. By Snowmass ’86 not only did decays to 4 leptons look like a principal mode in which to discover the Higgs boson, but calculations of the rate for the intermediate mass Higgs boson’s decay into two photons began to look like a potential discovery mode as well if the photon energies could be measured accurately enough. By the late 1980s, these two decay modes had become standard tests of performance for preliminary designs of SSC detectors, and each of the major detector proposals at the SSC had the capability to find the Higgs boson. Roughly 25 years later, the Higgs boson with a mass of 125 GeV was discovered in these two decay modes.

In parallel with working on science to be done at the SSC, including leading the Snowmass ’88 community workshop, my other focus in the late 1980s was on CP violation, both in terms of delineating the parameters of the standard model and testing whether it explained all the CP violation found in particle physics. A part of this was helping make the case for building electron-positron colliders that were “B factories” with sufficient luminosity to make multiple precision measurements of CP violating processes. SLAC was moving in the late 1980s toward proposing a B factory. During the same period, the SSC was on its way to beginning construction.

Zierler:

And who were the drivers of that? When you say it was looking like it was about to happen, who were the key people that were driving this possibility?

Gilman:

In 1985 the SSC Central Design Group was established at Berkeley, led by Maury Tigner. The senior leadership also included Dave Jackson, Chris Quigg, Stan Wojcicki, and its work was supported by many other scientists across the country. The CDG did yeoman’s work to produce a conceptual design report in 1986 and continued afterwards carrying out R&D and refining the SSC design. On the political side, President Reagan had approved the SSC project in 1987, and there had then been a site proposal and selection process that resulted in the choice of the Texas site.

Zierler:

And this is the design and cost for what it would actually be as proposed? We're not talking about a desertron. We're not talking about an addition to Fermilab. We're talking about as it was imagined in Texas?

Gilman:

We had a conceptual design report at that point which had to be made into a site-specific design report. I think a mistake was made at the time on the presentation of the cost that would haunt us later. The cost estimate for the machine alone was about three billion dollars. That was for a 6+ year project and was stated in 1986 dollars. It did not include the experiments, physics research staffing, R&D, etc., nor obviously inflation. It is true that many of those costs were captured in separate estimates and led to a cost around $4B in 1986 dollars. The next year, Reagan’s approval was for essentially the same project, but to start in 1988 and costing $5.3B in then-year dollars. But the $3B number was what stuck in important people’s minds, even if they knew better.

Zierler:

That’s why they're physicists and not salesmen. [laugh] They needed some marketers on board.

Gilman:

It’s not that they're physicists. Nor should they be salesmen. The CDG made a good estimate using panels of experts and followed the instructions from the DOE on what to include or exclude. People outside of physics who were not interested in physics at all had their choice of what number to cite.

Zierler:

Fred, that’s a number. But what about sites? Was anybody talking about where this thing would go?

Gilman:

The site selection process came after Reagan approved the SSC project, with an NAS study judging the merits of each site proposal and the DOE choosing the site. Texas was an excellent site with a layer of Austin chalk hundreds of feet thick to tunnel in, and surface land that was “only fit for raising armadillos.”

Zierler:

So just to be clear in this, the three billion is absent we know where this is going to go?

Gilman:

It’s absent many things, although to be fair, the conceptual design did average over three possible sites for the SSC. We already discussed a whole bunch of things beyond the accelerator construction project that are going to cost you, no matter where it goes. There were also important tensions raising their heads inside and outside the particle physics community. I already spoke in the first interview about the delicate balance inside Snowmass ’88 between those who came to continue building the path to the SSC and people coming who were devoted to projects other than the SSC and wanted to see those projects continue even if the SSC project was underway. As vice-chair of the DPF, I also encountered the increasing issues with scientists outside particle physics. I remember going with Barry Barish, then the chair of the DPF, to talk to the APS president, who was not a fan of the SSC, and trying to get mutual agreement with him on a statement that was coming from the APS council. So the beginnings of fractures within physics, which were going to be very costly, were already forming. Even within high-energy physics, it was clear to everybody that if you built a new frontier proton-collider, eventually proton physics is going to be centered there. What happens to Fermilab? And even though the SSC was to be built from funds in addition to the ongoing high-energy physics budget, once the SSC starts operations, what happens to the budgets for SLAC and the other labs?

Zierler:

Now Fred, when you say what happens to Fermilab, what happens to SLAC, is that an existential question? As in, is the question, “Will Fermilab exist post-SSC?” Or is it “What will Fermilab do next?”

Gilman:

It is what will they do as part of the full DOE national program. I did not think the DOE was planning to close a national laboratory. During construction, these questions weren’t immediate questions. SLAC wanted to build a B factory in the 1990s, and Fermilab had an upgrade of the injector into the Tevatron collider. However, particularly at Fermilab, part of their staff was going to build and test parts of the SSC during construction, and building the physics research staff at the SSC would mean some people and money from the ongoing high-energy physics budget would eventually go to the SSC.

In addition, the choice of who will be the director of the SSC project turned out to be divisive. As head of the Central Design Group, Maury Tigner, was an obvious possibility. When Roy Schwitters was chosen, the situation was made worse by the way the people in the Central Design Group were informed −or not informed−in advance of the announcement.

Zierler:

Do you want to comment, Fred, on why Schwitters and not Tigner?

Gilman:

No. I was an outsider who was not involved in any part of the search or recommending candidates. I did talk informally about the SSC fairly often with Pief at the time. Of course, he was very guarded about the search. The one issue I recall discussing with him was wanting a director of the project who would be the director through the ten years of construction. That was to avoid decisions being made by a director to manage short-term issues, but who didn’t have to live with their consequences in negatively impacting the SSC project’s ultimate success and physics performance at the end of construction.

Zierler:

So just like Pief was a young guy in the early, mid 1960s and he would be director forever, that’s the same kind of model.

Gilman:

Pief was extraordinarily young when he built SLAC. It doesn't have to be forever, but rather to the end of construction and commissioning. Returning to the issue of healing the community, later on I helped get some of my friends from the CDG like Stan Wojcicki to come to Texas and spend time helping with part of the supercollider’s experimental program; Dave Jackson became a member of the SSC experimental program committee. There was some healing with time.

OK. Now it’s September 1989, and there was the meeting of HEPAP and of the SSC Board of Overseers in Dallas that we talked about at the end of my first interview. Roy Schwitters, who had become director of the SSC Project, told me that the SSC Board of Overseers had been talking at their meeting about the search for the associate director of the SSC physics research division and considering me as a candidate. Am I interested? This was totally out of the blue, and came as an enormous surprise not only personally, but because particle physicists, including me, expected an experimentalist in that role. The associate director for physics research would oversee the construction of two major detector projects and the rest of the experimental program, build up the SSCL’s experimental and theoretical physics groups and labs, etc.

Zierler:

Fred, I want to ask — you're emphasizing all the reasons why you were potentially unqualified for this position. So I want to ask like a chicken and the egg kind of question. Because in 1990, you're on the High-Energy Physics Advisory Panel.

Gilman:

I was on HEPAP, right.

Zierler:

So do you join this panel because you start to work on SSC, or vice versa?

Gilman:

Not at all due to the SSC. HEPAP, to this day, gives advice in general — at that time only to the DOE — on the US program in particle physics. I was an ex-officio member of HEPAP because I was the chair of the DPF.

Zierler:

Right, but so what I'm asking is, as a way to understand, despite the fact that you're unqualified from the experimental and even the administrative angle, I'm wondering if one of the reasons why you were tapped was because of your work in high-energy physics from an advising perspective?

Gilman:

A number of senior members of the particle physics community evidently thought that I was qualified and urged me to take the job. You would have to ask others about that. I suspect that the different roles that I had played in the community generally were a part of the reason. Over a couple of decades, I had been on the experimental program advisory committees of all the high energy laboratories, had participated heavily in the physics studies for new accelerators, and a string of national planning exercises for the SSC and US particle physics generally. After our synagogue in Redwood City burned down, in 1979, I became president of the congregation and was deeply involved in every aspect of rebuilding. I had learned to work daily with a broad range of people, from sub-contractors, project managers, and architects to artists and fundraisers, along with advice from hundreds of congregants. While that was a few million-dollar project built on cost and schedule, what I learned proved invaluable a decade later.

Zierler:

Scaling up.

Gilman:

Yeah. A big, scaling up. I told Roy Schwitters that I would be a candidate and received a draft offer. Then came trying to decide what to do. Let me come back to the Reagan decision to build the SSC. Reagan put his decision in the context of an anecdote about the credo of Jack London — you can find this on the web in a column by George Will in 1987. The Jack London credo begins with “I would rather be ashes than be dust.” Somebody read it to Kenny Stabler, the quarterback for the Oakland Raiders, and asked him what it meant. Stabler replied: “Throw deep.” In part, that was what drew me to devote so much of my efforts to the SSC before I had any premonition of being part of the actual construction project. And it played a role in balancing the pros and cons of accepting the offer to lead the physics research division of the SSC project. There certainly were serious cons. First of all, I had a huge learning curve ahead of me that had to be mastered quickly. There was moving the family to Dallas. Although I thought that I could continue to do some theoretical physics research, it was not going to be anywhere near as satisfying as what I did for over two decades at SLAC and Caltech. I would go from where my daily schedule at SLAC was largely up to me, to where from early morning to the evening, I would have one meeting or event after another as I put together the equivalent of a high-tech start-up. I understood all that, and at times almost thought, “Am I really going to do it?”

Zierler:

This is full time plus, what you're looking at here.

Gilman:

Plus I would have to eventually — not in the first year or two while I was on leave from Stanford — I’d have to give up tenure at Stanford. And, on top of that, there’s a risk — everybody understood it−there’s a chance the project will be cancelled.

Zierler:

So taking an extended leave from your position, this is a non-starter?

Gilman:

I took a year leave that was extended to a two-year leave, but the general rule at Stanford was that you had to return after that. I think that it actually ended up during the third year that I had to make a decision. In any case, I knew from the beginning that eventually — obviously if the project succeeded−I was going to leave Stanford and be in Texas.

Zierler:

Fred, you already said Texas. And this is important, because I want to get this down. When is Texas settled on? When is it not the desert? When is it not Illinois? When is it Texas?

Gilman:

I don’t have in my head exactly the date, but after the Reagan decision in ’87 there was a competition with dozens of proposals that ended with the Waxahachie Texas site chosen by DOE in ’88.

Zierler:

So, it’s before Bush becomes president.

Gilman:

Yes, but not very long before. While it was very much a Reagan decision, George H. W. Bush was very positive about the SSC. I'll jump way ahead and state that I think if he had been elected for a second term, the supercollider would very likely have been built.

Zierler:

I think that’s a safe bet, yeah.

Gilman:

There was the challenge of the job itself. I made a return visit to Texas to talk to the people who were already there, of which there were about 20 in the physics research division at the end of 1989. There would be an order of magnitude more by the time 1993 comes around, maybe almost 300 with visitors. The more I learned about the job and the people that I could rely on to help me ramp up the physics division, the more I became convinced that I could do it. Taking on the challenge and to help create the future of high-energy physics increasingly became an attraction.

Zierler:

Fred, when you say this, how much of this is about the rivalry with CERN? How much of this was about, “We gotta do this before the Europeans do?” And how much of it is it’s gonna be done best at SSC and I care about science, and I just want the best for science?

Gilman:

Because it’s the best for science and the future of particle physics. At the time, I didn't realize how much the Europeans felt threatened. CERN had been studying both the possibility of a very high-energy electron-positron machine or the LHC. The book by Frank Close, The Infinity Puzzle, gives a brief account of the thinking from the CERN point of view based on interviews with Chris Llewellyn Smith and others. From the early 1980s when the idea of the SSC was first conceived, evidently leading European physicists saw it as a major threat to the future of CERN. The SSC would have far higher energy than anything that could be built in the LEP tunnel. I, and some others at SLAC, thought at the time that CERN would build a complementary electron-positron machine if the US built the SSC. In the end, they went ahead with a machine with about one-third the collision energy and ten times the luminosity, compensating for the smaller cross sections for production of new particles accessible to the LHC by having a much higher luminosity. I thought the SSC’s discovery potential would be essential for physics.

Zierler:

So what I'm specifically asking is, for those of you who were thinking, “This has gotta happen here in Texas,” was anybody saying, “And if this doesn't happen here, it’s OK, because the Europeans will do it”? And was that inconceivable at the levels that you were looking at creating in Texas?

Gilman:

The LHC did not have the physics reach of the SSC. I speak for many other people at that time who thought that we should build the next proton collider with a physics reach such that if nature put new physics of any kind that was associated with the mass scale of the weak interactions−a favorite was supersymmetry−other than have just a single Higgs boson−we would be able to fully explore and understand that new physics domain up to masses of new particles of roughly 1 TeV. As for CERN, I expected there would be lots of physics to go around for everyone, even with a late start. Given that LEP was beginning operations, it would be many years before you could take out the LEP magnets and infrastructure, insert new magnets and infrastructure, plus build the gigantic underground halls to hold the LHC experiments. People from CERN agreed privately. Nevertheless, Rubbia, who had become director general of CERN, in 1990 still presented a prospective LHC start date of 1998. Indeed, the LHC didn’t get CERN Council approval until 1994 and started doing physics in the late 2000s. Even with the stretching out of the SSC schedule when Clinton became president, the SSC would have been completed in the early 2000s and the Higgs boson, if that was what nature gave us, discovered in the first few years of running. I didn't worry about the LHC and focused on the machine that I thought we should build. As it turned out, CERN was fortunate that the SSC was cancelled and that nature cooperated with the Higgs boson at 125 GeV.

Zierler:

Fred, let me hear the narrative. Do you remember specifically when you said, “OK, I'll pull the trigger. I'll do this”?

Gilman:

It has to be something like late November. In October 1989, I flew to Texas to understand the job much better, meet my fellow associate directors, talk to Roy, etc. Here’s another historical event for you. I got off the plane at DFW, rented a car, and started driving into Dallas, and there was a news bulletin on the radio that there’s been an earthquake in San Francisco. A World Series game in Candlestick Park had been stopped. I thought, “OK, I've been through lots of earthquakes. There was shaking and people got scared.” Within minutes, the next news bulletin included that a section of the Bay Bridge had fallen into the Bay, and I was the one scared. I had no cell phone at the time. The moment I got into the hotel, I called home. No answer. I eventually got a call from my daughter in LA, who had talked to Barbara. She had been in the car on the way to a piano lesson with our two youngest boys. Our oldest son was in the family room of our Stanford house, and the whole bookcase fell over, but not on him.

Zierler:

Oh, wow.

Gilman:

Our family was not hurt and our house on campus was OK, as later verified by a structural engineer. I had arrived in Dallas for my job visit, symbolically [laugh], — at the time of the Loma Prieta earthquake. I went back with Barbara in November both to get additional questions answered about the job and to understand what our life in Dallas would be as a family. Shortly after that was when my decision came.

Zierler:

So when you decided, Fred, how many butterflies did you have in your stomach? Did you have a concern, a sneaking concern, that this was just not going to work out? Or did you accept this in a real moment of optimism? You're doing it because you think it will work?

Gilman:

I'm doing it because I thought the SSC was the right project to build and I could do the job. I fully understood that the project depended on yearly appropriation bills passed by the congress and signed by the president. I don’t know what number that I assigned at that time — maybe 20% that the congress would either cancel the project or decide to slow it down so that it would be finished years later than I thought it would. Nevertheless, I decided to accept the job. On January 1st of 1990, I became associate director of the supercollider project in charge of the Physics Research Division.

By this point, there was already a major concern that the cost of the site-specific SSC design was going to be significantly more than when Reagan approved the project. There were increases due to a two-year delay in the start of the project from 1988 to 1990 and a longer construction schedule. These were expected along with some relatively small changes due to the geography of the Texas site. Beyond that though, this time there were significant technical changes to raise the energy of the last ring of the injector and to increase the aperture of the magnets to have a larger margin within which to achieve the planned intensity. We all worried about the impact of the change in design and increased cost. Pief and others raised the question of reducing the collision energy, thereby having a smaller, less costly collider. There was a HEPAP subpanel chaired by Sid Drell charged to look at the question of whether to reduce the total collision energy from 40 TeV to, say, 30 TeV, with a corresponding reduction in cost of the collider?

Zierler:

So Fred, you're saying there’s a direct correlation there between the cost and the amount of energy being proposed?

Gilman:

Yes, if you have a magnetic field of a given strength in the collider bending magnets, then the radius of the ring goes up with the energy of the beams. Therefore, a higher beam energy means a proportionately bigger ring made up of more magnets of a given length. It also corresponds to more miles of tunneling, more infrastructure. and more cryogenics.

Zierler:

So even at the beginning, they're already talking about scaling back.

Gilman:

Right. And who’s going to present to the subpanel the trade-offs between collision energy and physics reach? Fred Gilman. However, on New Year’s Day, I went out to get a log from a pile of firewood and threw out my back for the first time.

Zierler:

Oh, no.

Gilman:

[laugh] In the first few days of 1990, I'm totally laid out on the floor at home while the subpanel is going to meet in Dallas. I got myself in good enough shape so that I could get on the plane to Dallas. In those first days at the SSC and making my presentation to the subpanel, I would sometimes be found on the floor of my office, and Roy would come in and say, “So you're sleeping on the job again?” In any case, the Drell subpanel’s report recommended keeping the collision energy at 40 TeV and preserving the physics reach. I commuted back and forth between Stanford and Dallas for six months, while my daughter was in her second year at UCLA, my oldest son was finishing high school, and the two younger boys were in grade school.

Zierler:

Where was your workspace? Where else were you, if you were not in California?

Gilman:

Good question. The SSC collider site was south of Dallas, around the town of Waxahachie, Texas. However, at that point, there was not much at the site yet. They were building the factory that would make the prototype magnets for the collider and prepare for testing the magnets, constructing the shafts and tunnels, etc. The main SSC office was in a warehouse that was just at the southern edge of Dallas. The first week or so I stayed at a hotel, but I soon moved into an apartment in a housing complex in DeSoto, Texas, south of Dallas in an area that was largely African American. My days typically began at eight in the morning, and often went to late in the evening. There were almost continuous meetings with the financial, engineering, and physics people who reported to me, with potential hires, and with my fellow associate directors and Roy Schwitters. In these first six months, the detailed site-specific design for the whole project was finished and reviewed intensively. Out of the approximately eight billion dollars for the whole project over ten years, approximately one billion was research and development on detectors, computing, the whole experimental program, plus building up in-house high-energy experimental and theory groups and facilities.

One of the very important people who came to help me was my friend Joe Ballam, who, as you’ll recall, had been associate director for research at the beginning of SLAC. His health now was not very good, but in spite of that, he would spend a week or two at a time in Dallas, helping me set up the equivalent division of the SSC. Again, there was the luck of having met him, first as an undergraduate at Michigan State, and then to become good friends and colleagues at Stanford.

Zierler:

When you say “reviewed,” who reviewed it?

Gilman:

After reviews using internal people plus experts from other labs and industry, there was the review by the Department of Energy, bringing in a large team of outside experts on all aspects of the project, drilling down to low levels of what is called the work breakdown structure (WBS) to see bottom up that the cost, schedule, technical specifications, and management all appropriately match at each level and for the overall project.

The concept and implementation of such reviews for major DOE Office of Science projects had been developed by Daniel Lehman and were called Lehman reviews. They were very intensive, with outside experts for each area, starting with presentations of the full project, and followed by days of parallel sessions. In each session, the experts in that area or sub-area asked probing, tough questions, and dug down for more detailed justifications if any argument or number appeared to be a weak spot. Each day the experts would report back to the review team as a whole, sometimes with resulting overnight homework for the project and/or a new parallel session to probe again. It was not unusual that in a Lehman review the contingency for some technical components was increased, making the project more expensive to the consternation of the proposers. I know quite a few project managers of accelerator or detector projects who much later were privately grateful as it allowed them to finish their project on budget or close to it. Once more, jumping ahead, I came to love Lehman when he led the 1992 review of the first of the major SSC detector projects, SDC, and the project team and technical design came through with a good deal of praise and small changes to the design and baseline cost.

Zierler:

Fred, what was your reaction to the $8 billion-plus figure we were talking about now? Is this doom, as far as you're concerned? Or you think the funding is there at this point?

Gilman:

My recollection is that we thought it was possibly very dangerous. Even when compared to the cost estimates from the late 1980s, let alone those from early on, we all knew it would draw negative reactions in the congress and it was going to amplify the-cost-is-out-of-control-chorus.

Zierler:

What about personnel? Where’s personnel in this?

Gilman:

They are all in the cost estimate, rolled up with the other costs from the smallest tasks to the whole project. This is unlike CERN, incidentally, where a large part of the manpower working on accelerator projects came from inside the lab and were included in the annual budget of CERN. In high-energy physics we called this U.S. accounting versus European accounting, and there was roughly a factor of two in that era between the official costs.

With respect to personnel, let me briefly touch on the people who I brought in to work with me to lead the Physics Division. Vera Lüth, who had been a staff member at SLAC, became my deputy for managing the experimental program. Harvey Lynch, also from SLAC, became my deputy responsible for detector technology, Jim Siegrist, whom I had known as a graduate student at SLAC, came from Berkeley to head experimental physics, while Bill Bardeen from Fermilab took on leading theoretical physics and Marge Bardeen engaged in education and public outreach. Already working on the project when I arrived were Ray Stefanski from Fermilab leading the experimental facilities and Mike Harris from CERN with his experience on the underground detector halls for LEP. Phil Leibold from EG&G, the industrial engineering partner of URA in building the supercollider, was my administrator for the physics division. I learned to do many new things working daily within the project, but also interfacing with the DOE and with the Texas National Research Laboratory Commission, which was managing a billion dollars outside the project to do everything from land acquisition to physics detector R&D. The latter program was within a hundred million dollars allocated for external research support for physicists around the country and was very successful.

Zierler:

This is a new world for you, in more ways than one.

Gilman:

Many, many ways, and especially a new world of people. Even inside high-energy physics it was a new world for me. After a series of calls first for Expressions of Interest, then Letters of Intent, and finally actual detailed proposals, the major detector concepts were winnowed down to two huge detectors. One was called SDC, for Solenoidal Detector Collaboration, a very mundane name. There were a very large number of US institutions involved, with George Trilling from Berkeley as spokesperson. Tom Kirk was the project manager. Internationally, there was a very big Japanese contingent, and significant European universities, who brought in more than 40% of the cost of SDC through in-kind contributions. The other detector at first looked to be L^* (LStar). There’s an interesting story as to the loss of confidence going that route, but in the end the SSC Laboratory decided to stop L^* from going forward. Parts of that collaboration, especially from Asia and Russia joined together with more US groups to propose the GEM (Gammas, Electrons, and Muons) detector in 1991. Barry Barish and Bill Willis were co-spokespersons, with Gary Sanders as the project manager. By the time they were ready for final review, each detector collaboration was headed to well over a thousand people and cost over half a billion dollars. For me, that all by itself was the experience of a lifetime. The other experience of a lifetime was working with my fellow associate directors and the top SSC leadership. To my mind, to the project’s serious detriment, we had three people who were like directors. Strangely enough, their initials were SSC.

Zierler:

Whoa! [laugh]

Gilman:

The first S, you already know — Roy Schwitters. He was the director that I worked for and had been designated by URA as Director of the SSCL to construct the SSC project. Formally, Schwitters reported to URA (as the contractor) and URA in turn to the DOE. Next, let me go to C. C was Joe Cipriano, who had the title of DOE SSC Project Director. He set up his office with a large staff very near the SSCL. Unlike Schwitters, Cipriano had a reporting line to Admiral James Watkins, former chief of naval operations, who was the Secretary of Energy. Watkins evidently didn’t trust the physicists to keep the project on cost and schedule, and Cipriano was the person he assigned to give him direct reports and alerts.

Zierler:

Was it your sense that he was supportive of the project; he was just concerned about keeping it in check?

Gilman:

I think that he wanted the project to be a success by delivering a collider on budget and on schedule. Previously, he had major roles in defense procurement management, especially in the Naval Sea Systems Command. But building the SSC was more than delivering 40 TeV proton-proton collisions. The physics reach depended crucially on the collider’s luminosity and interrelated properties of the injection accelerators, beams, interaction regions, and the detectors. We were constructing one unique, state-of-the-art high−tech scientific facility that would be upgraded in time, not a defense system with many copies to be produced.

The second “S” in addition to “S” for Schwitters was Ed Siskin. Siskin was parachuted into the SSC project (into the office next to mine) as general manager. Ed Siskin organizationally reported to Schwitters. Did you know his name?

Zierler:

I don’t know the name, actually, no.

Gilman:

I learned from Ed Siskin that at some point when nuclear submarines went on their maiden voyage, Watkins was in charge of the naval side, and he was in charge of the reactor side. They went way back to the Rickover days, and he could have had direct access to Watkins as well. I learned some fantastic stories about Rickover and the nuclear navy, some of which I have heard since then in documentaries. One of the other SSC associate directors was a vice admiral from the nuclear navy. When Rickover called him to give him instructions, he would hold the phone far away from his ear. Once Rickover had finished and hung up, he would soon get a call from Watkins who calmly explained what Rickover wanted him to do. [laugh]

Zierler:

That’s great.

Zierler:

So basically, Fred, what it sounds like is that it really never got worked out who was actually going to be in charge.

Gilman:

No, I am saying something more complex. Roy Schwitters as director of the SSC Laboratory led the people tasked with carrying out the plans for construction of the SSC project. That was especially true for physics research where the overall relationships with the particle physics community and the ultimate decisions on the experimental program were those of the SSCL director. However, people in the SSCL would get innumerable questions from the DOE SSC project office. We used to joke that every time they hired another person in the DOE project office, we had to hire somebody to answer all their emails to us demanding answers to the questions they had been asked by higher-ups, the Congress, etc., sometimes by the end of the day. When there were major cost-schedule issues, then the other directors could become engaged.

Zierler:

So that’s what I'm asking. Right. So they were all in charge.

Gilman:

Not actively in charge of construction, but continually present and watchful, especially of possible cost or schedule issues. Here’s a story that illustrates the situation in part. Starting near the beginning of the project there were monthly meetings to review the progress of the SSC project with each of the associate directors reporting the part of the project they were responsible for. Joe Cipriano attended those meetings. At the first such meeting that I attended, I gave a high-level account of the project accounts that I was responsible for, although not all cast in standard project terminology. At the next meeting, my presentation looked like those of the other associate directors and I gave a standardized accounting of the physics activities that were revving up and ended with the status of State of Texas funds that were outside the federal project. My detector R&D advisory committee had met and made recommendations on several dozen proposals, and I had already signed memoranda of understanding totaling over $10 million to many groups at universities and labs around the country. Cipriano looked at me and — said something like, “Watch out for this guy. He’s going to scarf up all the money.”

Zierler:

Literally and figuratively.

Gilman:

Very pointed and not appropriate DOE oversight directly into physics research, but coming from Cipriano, I could take it as a sort of back-handed compliment.

Zierler:

And at your level, who would you be reporting to?

Gilman:

Roy Schwitters.

Zierler:

And was that clear, you'd be reporting only to Roy, and that —

Gilman:

Yes, I reported to Roy always. The physicist from the DOE SSC Project office who was assigned oversight of physics research and the detector program and I became friends. A lot of the questions that arose on the technical issues with the detectors and their cost, including the international contributions were explained and talked out in one-on-one conversations. In any case, this was not where the major cost worries were, as the two major detectors were each to be built to cost about a half-billion dollars, with almost half of each detector coming from in-kind international contributions.

The SDC had its Lehman review and passed impressively. It was headed toward construction by the summer of ’93. The GEM detector was at the stage where it was to have a Lehman review within months of when the supercollider died. I had signed that summer the purchase order for 70-some million dollars to construct the magnet, which would have been the biggest open-field magnet ever built. It was to be roughly ten meters in radius and 30 meters long, with a field close to a Tesla. While GEM was going to be deep underground, with the open field we even had to worry about what it did to compasses and airplane navigation. That turned out to be well within acceptable limits.

OK, back to what happened to the SSC project and how it was stopped. I have a different view on the major factors than some who have opined on the subject. Number one, we never convinced the country — and in particular the Congress and the political and scientific leadership — that the SSC was worth building as part of US leadership in science and technology broadly. Even among physicists, some backed it, and others didn't.

Zierler:

Fred, was there a public relations component? Were there people whose job it was to do exactly what you said was not done?

Gilman:

Yes. There were, and they did a good job for those times with the resources they had, but it was nowhere near what we needed. Today, people across the basic sciences do a lot better, using all the modern tools to target multiple audiences. While this is a component of convincing the country, by itself it is not a leading factor in the project being stopped in my mind.

Zierler:

What was your sense of some of the structural problems in society that sort of made this job even more difficult than it was? In other words, if you look at what Pief Panofsky was looking to build in the early 1960s, he had a lot going for him in terms of what the United States was interested in at the time. Right?

Gilman:

Absolutely, the societal changes since the 50s and the end of the Cold War are at the top of the list. For decades, some of the leaders of the physics community had major clout in Washington, including Pief and what he was doing outside of science for national security and arms control. That was very important if not critical in the creation of SLAC. The particle physics community forgets how political the creation of SLAC and Fermilab was. Pief his written about the multiple times SLAC’s creation was in doubt, and whimsically remarked that SLAC’s initial budget allocation was made as part of a deal where there was also funding for a modification of a reactor at Hanford, noting that Stanford rhymed with Hanford.

Zierler:

So if you could just sort of paint a historical picture, what was it about early 1990s United States that even if the public relations people did the perfect job of saying why this was important, what were those things that were sort of — you were going up against that had nothing to do with how important it was or how well that work was being conveyed?

Gilman:

OK, Number Two — the SSC was a line item in the federal budget each year for a project costing many billions of dollars, at exactly the time when people were looking to control spending and cut the budget — people from Texas in particular were among the chief budget hawks. Shortly before the vote that killed the SSC, Senators Gramm and Hutchison of Texas plus Ross Perot, had a press event at the Capitol, talking about cutting the federal budget.

Zierler:

And these are true believers. Even if this would have been good for Texas, they were still against it?

Gilman:

No, on the contrary, they were strongly for constructing the SSC. There was a dichotomy in their minds, and it made many people mad. That some people didn’t see the SSC as worth building for the country was bad enough, but to see it simply as a Texas project — that made it far worse. I assume that’s the context you’re alluding to, in part. This was a deeply divided time — between Democrats and Republicans, or between liberals and conservatives, about spending more, particularly on social issues, versus cutting budget deficits. Coupled with the narrative of increasing SSC project costs that goes back to CDG days, this was deadly.

Zierler:

And here’s another “what if.” The “what if” is had Bush been reelected, probably it would have gone through. Another “what if” is what if the Cold War was still on? What if the Soviet Union hadn’t collapsed?

Gilman:

In fact, I was going to say that there is a preface to all this discussion — Number Zero, if you will, is the overall context that the SSC saga is played out in, which is the international and national context: the world as the Cold War decreased and ended, the competitive economic relationship with Japan, and especially who is president of the United States. You just alluded to my opinion that if George H. W. Bush had been reelected, the supercollider would likely have gone forward. Part of that opinion was my understanding at the time that there might well have been a one- to two-billion-dollar contribution from Japan. We came close to that quite early on when it was reported to be high on the agenda of a planned summit meeting between Bush and the Prime Minister of Japan centered on tariff issues. That trip was postponed, and by the next year, the stars did not line up in the same way, to put it mildly, and Bush was sick at dinner. Bad luck, that the meeting didn't happen early on as planned.

While not at the levels of importance we have been talking about, I would add something else to the list of things that I believe played lesser roles. It was the arrogance of some high-energy physicists which came back to the detriment of the project. While it’s hard to know how much effect this had, I'll give you two incidents to think about. After Clinton became president, there was a briefing on the SSC project for Vice President Al Gore. I heard about the meeting afterwards from others who were there. There’s a brief account of it in Pief’s autobiography. Although he was engaged enough by the discussion of the physics to ask a question about what happened before the Big Bang, the opportunity to get Gore’s strong support for the SSC was lost.

Zierler:

Even worse, Al Gore fancied himself to be science literate.

Gilman:

You bet. Gore was the person we would have liked to have become a champion of the project. When the space station came up for approval, he was widely reported to have worked right up to the vote to make sure it passed the House − I think by one vote.

Zierler:

So this is an important point about NASA and Gore’s support for NASA. Was your sense that this was essentially a binary budgetary issue? The money would have gone either to SSC or to NASA? Was that your understanding?

Gilman:

My understanding from Texans then, as well as other people’s accounts later, was that Ann Richards, the Democratic governor of Texas at the time, and Bill Clinton had a conversation about the two large “Texas projects” — so we’re back to billion-dollar, Texas-related items in the budget — and it was unlikely both would survive. They gave priority to the space station, which had more political support as part of the space program, as well as had pieces being built and NASA facilities in many different places spread across the country. Not many people even knew that their local university or lab or industry had anything to do with the supercollider. Clinton officially continued to support the SSC but stretched out the construction schedule by several years. Everyone understood that this would raise the cost of the project significantly from marching army costs. The chorus of opponents would start the chant again, “The cost is out of control!”

Zierler:

So Fred, to put this in historical context, when did you start reading the tea leaves that this was falling apart? And then when did you know it was done?

Gilman:

Let me come back to my reading of the likelihood of the project being cancelled, and first relate another way that our arrogance came back to bite us. Arguably the most prominent leader of the scientists who publicly opposed the SSC, including testifying against the project to the Congress, was Phil Anderson. I learned long afterward about conversations friends of mine had with him during the height of the battle. Anderson raised arguments he had stated publicly many times against the use of federal funds for big projects in one field like the SSC rather than broadly support other fields of physics and funding smaller projects, particularly in condensed matter physics. But it also emerged that he had been strongly offended by particle physicists calling solid state physics “squalid state physics,” devaluing the science and putting him and his condensed matter colleagues down. Fast forward to 2002 when Curt Callan, from the graduate class before me at Princeton, had his 60th birthday fest. I was one of the speakers and at that point was the chair of HEPAP. I spoke about the future of high-energy physics, a talk that I gave many times during the time of the Bagger-Barish HEPAP subpanel, including the US hosting an international linear collider. The end of the talk emphasized that a plan for high energy physics needs to part of a much bigger plan for all six science areas within the DOE Office of Science. I compared having only one big high-energy physics project to sending out only the flagship without the rest of the fleet. It’s likely to get sunk. The whole fleet of basic science should go out together. Afterwards, Phil Anderson, whom I had never met before, came up and introduced himself. He made a positive comment on my talk and then said that if we had in place the concluding message of my talk at the time of the SSC, he would have felt differently about building the SSC. I've told about this interaction with Phil Anderson to a few of my high-energy colleagues — some of their reactions are, “So what? Now it’s easy to say, especially since he knows that the money that was planned for the SSC did not go to other parts of science after its cancellation.” But I think it is significant. He didn't have to come up, introduce himself, and talk with me at all. Perhaps it did touch him in some way.

Zierler:

Wow.

Gilman:

Now, back to when did I know. I knew there was a non-negligible chance when I accepted the job. In ’92, the House voted to stop SSC construction by a relatively narrow vote. The Senate voted for continued construction, particularly due to the leadership of Senator Bennett Johnson from Louisiana, who was the very powerful chair of the relevant Senate appropriations subcommittee. The bill that emerged from the House-Senate conference, which funded continued construction for fiscal 1993, was approved by the House and the Senate. In the background, Bush had apparently made it clear that he would not sign the final bill without the SSC in it. At that point we all knew that the next year was crucial and would also depend on the presidential election and who controlled the House and the Senate. Dick Taylor bluntly told me at the International Conference on High Energy Physics in August that he thought the SSC would not make it through the next year. While understanding that it would be close, depending in part on the election, I still argued it would make it through. I was wrong: With the stretched-out construction schedule and increased cost in the Clinton budget proposal, the House voted more strongly for termination. The Senate was positive, with the republicans strongly for and the democrats marginally against. After the secretary of energy’s congressional testimony late that summer blasting the URA management of the project, I felt there was no real support from the top of the DOE and that only a small miracle could have saved the project. While Bennett Johnson managed to get continued construction back in the bill that emerged from the conference committee, the opponents were outraged, and the House voted to amend the bill and stop SSC construction by almost two to one in October 1993. The project was dead, with no reasonable path to revive it. One of the things I heard at the time which stuck with me was a leading proponent’s remark that, “It’ll take 20 years for the smell to go away in Washington.” He was right. At the time, I thought that the smell would go away because those involved would mellow or their memories would fade. What happened is that twenty years later when I talked to a science administrator or to a congressional aide — not aide, what do you call it?

Zierler:

Staffers.

Gilman:

Yes, congressional staffers. Rather, as I heard in the last few years talking to the staffers of congressmen and senators, the smell went away because they were too young to remember. They would ask, “What’s the SSC?” There’s no smell left when people don’t even know that the SSC project ever existed!

Zierler:

Fred, how much was actually built, and bought, where you now needed to figure out, “What do we do with this stuff, and how do we get the land back to where we found it?” How big a deal was that?

Gilman:

A big deal. First of all, the DOE wanted to distance itself from the project as far and as fast as possible. Roy Schwitters resigned almost immediately, and John Peoples, the director of Fermilab, became SSC director during the termination phase. I continued as associate director for the physics research division. When John left after a year or so, I became the deputy director, reporting to George Robertson, a retired army general previously one of the other associate directors, who became the director for the last stage of termination. The project was 27% complete. Correspondingly, about a quarter of the roughly billion project dollars planned for R&D, computing, the experimental program, scientific and technical staff, etc. had been spent. I devoted the next year and a half to distributing equipment to the other DOE labs, including the parallel computing facility for physics simulations that we had built from scratch to Livermore; getting the detector and other technology written up so that the knowledge could be transferred to other experiments in the US and at the LHC; and most importantly, helping people across the division find jobs. Most went to universities or labs in the U.S. and stayed associated with particle physics. Some went to industry, and a few, quite successfully, went to Wall Street. There were very few of the physicists or technical staff who didn't find a job. And, of course, a large part of the U.S. physicists who were in the SSC and GEM collaborations soon joined the major LHC detectors, ATLAS and CMS.

Let me come back to the termination of SSC construction and what for me was the lowest point of the whole process. I had heard of the nastiness of the SSC discussion behind the scenes in Washington, with an intensity by some of the project’s opponents that went beyond an argument over cost or the best use of the money. Some displayed a lack of compassion for the tragedy that had befallen those who had been building it. After the vote of the House, the SSC project was officially terminated toward the end of October 1993. In November, the secretary of energy came to Dallas to introduce John Peoples as the new director in a talk to the SSC project’s staff. Peoples found that there was going to be a minimal severance package at best for the project’s almost 2000 employees. He would not take on being the director without an adequate severance package. The DOE backed off, and there was a reasonable severance package. John has my admiration from that time for standing up for the SSC staff. While some in upper management could go back to a lab, university, or industrial position, many−like my division’s financial administrator, safety officer, and a large part of the administrative staff− had come to Dallas from afar, with no immediate employment in sight.

Zierler:

Fred, I want to ask you personally — hindsight is 20/20 — did you feel dumb at the end of the day for having given up a tenured position at Stanford?

Gilman:

No.

Zierler:

You didn't?

Gilman:

No. At the time of cancellation of the SSC, I concentrated on getting people jobs, closing down all the activities, etc. that I described before. My real period of mourning came only after I arrived at Carnegie Mellon, when it all sort of hit me. Looking back at the closeout, I just kept going, trying to do the best I could for the people around me, sending out termination notices as best as I could to people who already had a job prospect or could likely find a job, and sending the technology and people off to do physics at the LHC. Early on in the closeout, two of the division’s senior administrative staff came together to ask me how I was holding up, as in their similar roles for the president of a university and director of a medical center they had witnessed people collapse under similar circumstances.

To this day, and I've said it to many people, I do not regret going to the SSC, because of the huge learning curve that I climbed, and things that I accomplished that I would never have had the opportunity to do in my life. It’s especially the people that I met, the people that I hired, the larger-than-life Texans who remain among our good friends and the friends of our two younger sons. It helps that I landed on my feet, so to speak, and used my experiences to do other things. I would do it all over again, even knowing the tragic outcome of the project.

Zierler:

Fred, I want to ask you — and I'll frame it this way — a prominent theoretical physicist, I won’t say who, his reaction to the loss of SSC was, “Well, so what? We ultimately found what we needed to find at CERN.” What is your response to that specifically, as part of the broader question of what was lost to high-energy physics and physics in general as a result of SSC never being built?

Gilman:

I think that the prominent theoretical physicist is correct, although you don’t have to be either prominent or a theoretical physicist to make such a statement about the Higgs or to make the opposite statement that we didn’t need the LHC if we had built the SSC. It’s also correct to say that we didn’t need the SSC to find out that there is no evidence of supersymmetry, or technicolor, or a complex Higgs sector up to now in the range of masses accessible so far to the LHC.

The SSC was built with what was called a no-lose theorem. Either you'd find a single Higgs boson or you'd find some new physics in its stead below the trillion-electron-volt scale. And if the new physics was, for example, supersymmetry, you would have gained many deeper insights into nature, including perhaps finding the particle making up dark matter and/or a sufficient source of CP violation to give us the universe we live in. Instead, nature gave us one Higgs particle, at least so far, and we're still trying to figure out what’s next. For me, the deepest questions that I hoped to have answered at the SSC remain. Would the supercollider with three times the energy of the LHC have found something major beyond the Higgs? I don’t know, but maybe. Instead, it is CERN that is thinking about a Future Circular Collider that in its final phase after 2050 is a hadron-hadron collider with a total collision energy of about 100 TeV in a new tunnel with a circumference of around 100 km. If the SSC had been built, a functional 87 km tunnel near Dallas would have existed two decades ago into which a Future Circular Collider’s high-field magnets could be placed.

Zierler:

Fred, I want to make sure I understand this correctly. So you're asserting now that because SSC was not built, just because CERN went on to do the things that it did, there are things that we would have discovered today that we still don’t know had SSC been built?

Gilman:

No.

Zierler:

In other words, CERN didn't entirely pick up the ball?

Gilman:

No, it’s not about picking up the ball, it is how far you can run with the ball. I don’t know either way. It is possible that nothing beyond the Higgs would have been found at a 40 TeV SSC. But it could be that the much higher energy of the SSC would have allowed discoveries beyond the Higgs, discoveries for which the LHC is simply below the energy threshold for their production. It could also be that the next energy threshold is, as a more pessimistic example, at a PeV — a thousand TeV — so that both the LHC and SSC would have been far below the new-physics threshold.

Zierler:

Not even China?

Gilman:

Not even China for the 100 TeV machine. I can’t say forever, but I don’t see China doing it alone, and looking at the growing political and economic competition, an international collaboration with a Chinese site looks unlikely to me. Moreover, I now don’t see society across the planet, with all the problems currently confronting us, putting tens of billions of dollars into a new collider with an unknown discovery potential, especially when other parts of science aside from particle physics have made enormous progress, with fascinating insights that affect our everyday lives.

Zierler:

Let’s now move on to your tenure on the High-Energy Physics Advisory Panel. To what extent was it aiming to reconcile community interests into an agenda? And to what extent did it regard itself as advocating on behalf of it? How did that work out?

Gilman:

If I understand the question, HEPAP was constituted to advise the DOE originally. Advising the NSF, who sat in on HEPAP meetings for years, was added officially when I was chair of HEPAP from 1999 to 2005. Also during my tenure, the astronomy and astrophysics advisory committee was formed to advise the NSF, DOE, and NASA. One of the other things that occurred while I was the chair of HEPAP, is that Keith Hodgson from Stanford, who was then chair of the DOE Biological and Environmental Research Advisory Committee, organized all six of the advisory committee chairs to the DOE Office of Science to go to Washington together. At least once a year, we would all assemble in Washington to get briefed on the current issues facing the Office of Science, especially the budget for the next fiscal year. Then we would meet as a group with key members and staffers of the science committees and relevant appropriations subcommittees of both the House and the Senate to make our case for science in general. We testified together before the House Committee on Science, Space, and Technology, and also met with the relevant OMB examiners.

Zierler:

And to the extent that people like John O’Fallon and Martha Krebs and other senior leaders at DOE — post-SSC, was your sense that they were sympathetic because high-energy physics needed a boost? They needed that level of support in terms of the existential questions of “Where do we go from here?”

Gilman:

Yes, O’Fallon and Krebs were very concerned with the health of high-energy physics post-SSC. Soon after the SSC died, another subpanel chaired by Sid Drell was convened to give a basis for short terms actions to bolster high-energy physics, especially as the portion of the field devoted to the high-energy frontier pursued at the SSC was now closed. Their recommendation of course was that the US should join in construction of the accelerator and the experiments for the LHC, which all came to pass after a few years of negotiations. There was to be an increase in the budget for a few years−the Drell Bump–to help the field transition. Without such a bump, the subpanel’s report called for a new HEPAP subpanel to plan the long-term future of the field within the diminished US program. A decade and a half later, the then-Director of the Office of Science, addressing the representatives from the URA universities noted that in the 1990s fusion and high-energy physics had been deemphasized. He wasn’t announcing anything that we didn't all know, but the matter-of-fact reference struck me as someone who lived through the deemphasis day by day. When I succeeded Mike Witherell as chair of HEPAP in 1999, High-Energy Physics (HEP) still had the biggest budget of the six suboffices of the DOE Office of Science, but Basic Energy Sciences had been catching up quickly and was about to pass it. When I looked again a few years ago, the budget of Basic Energy Sciences was two and a half times that of High-Energy Physics, which in turn was down once inflation was taken into account. The other area that has risen dramatically is Advanced Scientific Computing. That directly reflects the priorities of the country.

Zierler:

Now, the earlier Drell report from ’93, ’94, what was your sense of the intended audience for that?

Gilman:

The Drell subpanel right after the SSC died?

Zierler:

Right, right. Who was the audience for that, and what were the key challenges presented when Congress failed to provide what was called the Drell bump? The temporary bump in funding.

Gilman:

I think the primary audiences were the administration and the Congress. The report provided the beginnings of a roadmap for high energy physics immediately after the loss of the SSC. In particular, the secretary of energy and the DOE managers could immediately use the report to inform the budget proposal for the next fiscal year. It also gave them the backup to begin preliminary discussion on US involvement in the LHC and to continue the paths toward construction of new facilities at Fermilab and SLAC. Also in the report was a recommendation against continuing the superconducting magnet facility at the SSC site. The federal property was all to be shipped off to other DOE entities, from the accelerator components to the cafeteria equipment. It was made clear to me in a meeting with Sid close to the time that his subpanel’s report was to become public that the rest of the DOE high-energy program wanted the site totally closed down. The SSC was quickly dismantled, the people went away, and the U.S. got involved in the LHC, as it continues to be 25+ years later.

Zierler:

And did you see this as a sort of generalized threat to the HEP? For example, in terms of from the university community to projects such as the B Factory and the Main Injector, and the way in which the United States was willing to participate in the LHC?

Gilman:

Why was it a threat? I don’t understand the word “threat.”

Zierler:

No, no. The threat is that HEP — the concern was that, would this be viable going forward, post-SSC.

Gilman:

It was viable, but at a much-reduced scale to our hopes of what the field would look like. At a reduced scale, it was a viable plan that touched all the players. They got an overall path forward and continued to advance at a lower budget level. Further, if there was no bump, the rest of the path forward would come from a more detailed and prioritized plan to be developed by the next subpanel.

Zierler:

Can you talk a little bit more about the considerations for the U.S. developing a role at the LHC? For example, was there a concern that participation in the LHC would further dampen appetite for HEP initiatives in the United States?

Gilman:

I don’t think so. At the high-energy frontier, long-term the U.S. was to participate in the LHC. In the meantime, before the LHC turned on, Fermilab’s Tevatron collider was the machine at the high-energy frontier, and it was to make a run at trying to find the Higgs, as well as do lots of other physics. Away from the high-energy frontier, plans for the B Factory to be built at SLAC were underway while the SLC was running, as were plans for the main injector and for increasing the luminosity of the Tevatron collider. Neutrino physics was progressing, and we started to move in the direction we are following now with a major underground laboratory and neutrino source at Fermilab. Our dreams got reduced, but there was still an active field that is working at the frontier in a number of areas. It didn't and doesn’t have the priority either within DOE or in science as a whole in the U.S. that it had before.

Zierler:

Now, the ’97, ’98 report that you chaired — is that called the Gilman report?

Gilman:

It was sometimes called the Gilman report because I was the chair, just like others are called the Drell report or the Bagger-Barish report. There’s an official title.

Zierler:

No, but colloquially, is that how it’s referred to?

Gilman:

More often it’s referred to as the Gilman subpanel. Just like the next one was the Bagger-Barish subpanel.

Zierler:

Can you describe what some of the needs were as you articulated them and the process of assembling the report? What were the things you were looking to accomplish with this report, and how did its creation come about?

Gilman:

After the Drell subpanel’s short-term plan immediately after the cancellation of the SSC, both the DOE and the high-energy community needed to have a comprehensive, prioritized plan for the field for a decade. You might call it a continuation of putting U.S. high-energy physics back together. The central budget scenario was constant level-of-effort, And the subpanel was forced to establish sunset times for a number of ongoing activities at Brookhaven, SLAC, and Fermilab in order to fit into that budget. In addition to prioritizing the next steps in research directions that were already planned or underway and to have U.S. participation in the LHC, there were two big portions of the subpanel’s report that were new. One was on the status and future of the university-based portion of the program, including demographics, infrastructure, funding patterns and processes, etc. That portion of the subpanel’s work was led by Abe Seiden. The other was to guide R&D on a possible future machine at the high-energy frontier that would be complementary — with an “e” — to the LHC. There was also the beginning−something that would grow dramatically over the next two decades −of a portion of the report on astroparticle physics, including SLAC’s involvement in what was then called GLAST, now called Fermi, plus Jim Cronin and collaborators headed toward a major cosmic ray effort with Auger. While the machine complementary to the LHC was envisioned to be built in the U.S., it was clearly recognized that it would be an international project. The candidates were: a linear electron-positron collider; a muon collider; and a Very Large Hadron Collider.

Zierler:

And this is not either/or. These are all projects that could theoretically — ?

Gilman:

In parallel?

Zierler:

In parallel.

Gilman:

In parallel for R&D. It was very carefully stated in the report that “This is not a recommendation to construct. This is a recommendation to do R&D to see which of these might be the right project for the United States to take a lead role in.”

Zierler:

Can you talk about what the idea was for post-Tevatron, for a high-energy facility post-Tevatron? How did HEP settle on the International Linear Collider project? And what were the prospects for spinning up major new collaborations?

Gilman:

To answer, let me come back to the three possibilities. A muon collider — muon-antimuon collisions at a total collision energy of several TeV — was one of the proposals. A collaboration to do R&D involving Brookhaven, Fermilab, and universities had formed. To produce intense colliding beams of particles that only live 2.2 microseconds at rest is an accelerator physics and technological tour de force that involved many years of R&D just to prove the concept. I recall the subpanel’s reaction when a realistic timeline was presented, and the panelists around the table understood that very few, if any of us, would be around when such a collider was producing physics, even if the R&D and prototypes were successful. The subpanel recommended support of further R&D with a review of progress in a couple of years. The second possible future accelerator was a very high-energy proton-proton machine, with a total collision energy of roughly 100 TeV. That idea, as we have discussed, is still very much alive as a successor to the LHC. But recall at the time of the subpanel, we had no idea what would be discovered at the LHC. Further, if you were going to build such a machine, it would involve an international collaboration. It would depend on what CERN was going to do, even if it is not built near Geneva. The Fermilab team had some interesting ideas on how it might be possible to build the tunnel and the magnets more cheaply, and the subpanel again supported further R&D and a review in a couple of years. The third option was an electron-positron linear collider. In this case, R&D had been ongoing for years at SLAC and an international collaboration formed with KEK in Japan. An operating linear collider — built with an eye toward showing that you could solve many of the technical issues−the Stanford Linear Collider, was producing Z bosons. To scale up to a total collision energy of 1 to 1.5 TeV and the high luminosities proposed to the subpanel involved many technical issues including greatly increasing the voltage gradient in the colliding linear accelerators in order to make the machine much shorter and less costly. The subpanel consequently recommended increasing R&D funding so that a conceptual design report could be delivered by SLAC working with KEK. Jumping ahead, this effort evolved into a global design effort for an International Linear Collider led by Barry Barish. They eventually settled on a superconducting RF machine, rather than one at “room temperature” like the SLC. The voltage gradients and other parameters were such that you could think of building such a machine with total collision energies of 0.5 to 1 TeV. In the end, the big questions that remained for an ILC by the late 2000s were not so much technical or scientific, as they were social, political, and economic. I do not see an ILC happening in the near term. CERN has got its work cut out for it with the LHC, upgrading and running the High Luminosity LHC, and after that the High Energy LHC with high-field magnets. The world has put and will continue to put enormous resources into that effort. Aside from perhaps Japan, the country that has the potential interest, economy, and technological level to take the lead on an ILC is China, and as I have indicated earlier, I don’t see them doing it alone, nor as an international project given the present political and economic competition. In the US, not only do we have great political divisions on almost every issue, but Drell, Panofsky, Goldberger… who had huge roles to play outside of high energy physics, all have passed from the scene.

Zierler:

Right.

Gilman:

I don’t think there’s a single — maybe you can tell me the name of somebody — a single high-energy physicist who has the same level of recognition in Washington. Can you think of anybody even vaguely close?

Zierler:

That’s a Google search, but the fact that it’s not so easy to answer is telling in and of itself.

Gilman:

You can name a few scientists who do, but not particle physicists.

Zierler:

We talked about Bush to Clinton. We haven't talked about Clinton to Bush. What did that mean — Bush II, obviously. What did that mean for the HEP community when Bush became president?

Gilman:

Instantaneously, Bush continued the plan to double the annual budget of NIH. That remained a high-level priority. The budget of NIH was indeed doubled to $27 billion in FY03, and then grew much more slowly until the last few years. The 2007 Rising Above the Gathering Storm report of the national academies led by Norman Augustine on the growing challenge of China came toward the end of the Bush administration. It did lead to plans to invest strongly in STEM fields, but the increases ended up being quite modest compared to NIH. When Bush came into office, we were just going into a recession as the dot-com bubble burst. In my first full year as chair of HEPAP during a meeting at Fermilab in 2000, we learned that for the first time the proposed budget of high-energy physics was roughly flat−the same dollar amount as the previous fiscal year. In the end, it got adjusted, but still did not keep up with inflation. We’ve had repeated bad luck with respect to the timing of major national and international events around us.

Zierler:

This might be a crazy question, but with another Bush back in the White House, and Texas being right back there in terms of national agendas, did anybody talk about reviving SSC? Did that even come up for a second?

Gilman:

Nope, not even for a second.

Zierler:

Why? Just like it’s impossible? There’s nothing to talk about?

Gilman:

Right after the project was stopped, there were people with wild ideas of how to revive the project. Crazy ideas that never happened. After that, forget it. For the DOE, the SSC was an enormous embarrassment. They didn't want to touch it with a ten-foot pole, and George W. Bush had lots of other things to worry about after September 11th.

Zierler:

That’s it. Right, right. I should have specified that had anybody been considering a revival of the SSC, obviously it would have been pre 9/11, if at all.

Gilman:

Nobody had that wild idea.

Zierler:

One of my colleagues astutely observed that the Bagger-Barish report had a quite glossy production, that it looked professional. It looked really well done.

Gilman:

It was quite different in appearance than all the previous subpanel reports which followed a template that must have gone back decades, all in black and white with a choice of a monotonic cover color.

Zierler:

What was different about it, and why so glossy? What was the idea there?

Gilman:

We had by then seen reports produced by other parts of science and from the DOE labs that were aimed at a broad range of audiences. Working with people doing PR for the labs, the time had come to get our act together. I set up what I initially termed a HEPAP writing group when I became the chair. It produced a briefing book of slides and pictures that we called Interactions, the Science of Matter, Space, and Time. It was aimed at a wide audience, from fellow academics and academic administrators to those in the Congress, their staffers, and the OMB. A very important role was played by Judy Jackson and Neil Calder, the public affairs leads at Fermilab and SLAC, who continually pushed us to write so that it drew the reader into the awe of the questions and the adventure of people trying to answer them. For the Bagger-Barish subpanel, not only was the report itself in this new format, but a new group was formed to produce a companion document for a general audience interested in science, Quantum Universe. Did you ever see that?

Zierler:

Yes. Which was also glossy, and also seemed like its intended audience was quite broad, actually.

Gilman:

I was able to convince Persis Drell, who had been on the subpanel, to lead it. She did a great job. When it came out, we went to Washington, and Persis, I, and a few other people, went to introduce it to key congressional staffers. Persis would lead off with the mysteries of dark matter, dark energy, and the few percent of the universe that is ordinary matter. The reactions were different than in any other visit. One of the lead staffers for appropriations said, “Wow.” Another said something like “You're kidding” and started asking questions. I think it did have a very positive effect not only on staffers and the congress, but also those in the OMB and OSTP — although budgets didn't jump up immediately, but —

Zierler:

But is that the only metric, in terms of its success? If budgets jumped?

Gilman:

Right, it’s not. First, it had an important role in educating science writers and those interested in science among the general public about the frontiers of particle physics broadly and to better understand what we're doing. Within the academic world it gave a tool to hand to colleagues or students or to show to their dean as a reference and part of a conversation on resources or hires. It was followed by another glossy report on Discovering the Quantum Universe: The Role of Particle Colliders. Along with many other fields of science, medicine, and engineering — back to the theme you heard earlier — we’ve learned to communicate much better the excitement of our science and why the people who do it merit support.

Zierler:

In terms of the report being intended for a broader audience, besides the budget, what were the motivations for that, and how well were those goals met, do you think, in terms of what the report was aimed to do?

Gilman:

I think the report met its goals in the short to medium term. Jack Marburger had a couple of pictures from it in the hallway outside his office as science advisor, and it helped me a great deal in briefings of the OMB, OSTP, and Ray Orbach, who led the DOE Office of Science during the Bush administration. Orbach, a well-known condensed-matter physicist, took us on in a serious way, understanding the big questions in high energy physics in depth, and giving us plenty of homework to supply more about the physics and detailed plans after meetings. He had HEPAP produce a short list of priorities as part of his twenty-year facilities plan that he constructed in 2003 for the whole Office of Science. Five of HEPAP’s top six priorities made it into his final list The International Linear Collider was at the top of the mid-term priorities. In effect, he became one of the most important proponents of trying to get the country to build, within an international collaboration, an electron-positron collider. Before I left as chair in 2005, the Global Design Effort for the ILC was in place. The full technical design report did not come out until 2013. I believe that the chance of having it built in the U.S. went away as the DOE’s estimated costs went into double digits in units of billions of dollars and a new administration took office.

Zierler:

Some questions on P5. I'll just state all of the Ps — Particle Physics Project Prioritization Panel.

Gilman:

That’s another product of the Bagger-Barish subpanel. Let me go back to the Gilman subpanel which recommended that there be a periodic, competitive review of all the university grant proposals up for funding, rather than evaluations of each proposal individually. This was partly driven by a number of physicists writing to the subpanel that funding continued for some people when they were no longer as productive as in the past, while junior faculty beginning their careers were underfunded. The DOE High Energy Physics program officers were reluctant to give up their option to review proposals individually. Of course, for issues affecting the field as a whole they asked HEPAP for advice, but even in those cases DOE asked HEPAP specific questions or directed subpanels to answer specific charges. The subpanel’s recommendation to do a periodic comparative review of proposals from universities led to having individual reviewers rate a few proposals relative to each other, and a comparative review of a portion of the proposals, but the recommendation to have continuing competitive reviews of all the university proposals in a given funding cycle wasn’t implemented.

The Bagger-Barish subpanel meeting to decide on the recommendations and to begin writing the final report took place in Santa Fe in September 2001. September 11th was the second full day of the meeting. This time there was a united subpanel that wanted the particle physics community to set priorities periodically for the whole field. A subgroup drafted the concept and invented the name P5. My recollection is that members of the subgroup were especially effective in getting the agencies to see the merits of a community-driven process to set priorities rather than a process that was sometimes opaque and left the funding agencies open to challenges of a decision by portions of the community. Soon thereafter, the first P5 started to function. As chair of HEPAP, I was an ex officio member of the first couple of P5s. I think it has been a very good system. After P5 was in existence for several years, everyone understood that P5 gives both the field and the agencies greater credibility with respect to the priorities of the entire program and it helps get the OMB and congress to respond positively.

Zierler:

Did you see the planning process behind the P5 as something different from the decadal process as it is today?

Gilman:

I think the inspiration is similar, and to a lesser degree, the decadal process inspired parts of the 1997-1998 subpanel. As I maybe mentioned to you before, John Bahcall was a close friend of mine from Caltech days, and he had led the Astronomy and Astrophysics 1990s survey. When I became the chair of the 1997 subpanel, we had several conversations on his experience and ways that the subpanel process and report might have parts more like the decadal survey. When the subpanel was formed, I learned that there was a Committee on Elementary Particle Physics chaired by Bruce Winstein working on a report to the Board on Physics and Astronomy that was one of a decadal series of reports on areas of physics. The groups worked independently, but once we had a draft of the subpanel report, we communicated our summary and received feedback that we were generally in accord. Of course, given the constraints of the DOE and the specific charge to the subpanel, we had an intentionally limited timeframe and set of topics, plus we inherited a process used many times previously. If you look back, you can see some of the subpanel’s recommendations and process as in the vein of a decadal survey. Behind the scenes there were anonymous straw votes on prioritized projects inside budget-scenarios, followed by candid discussions inside the subpanel. It wasn’t a decadal survey, but some of the seeds were planted for what came later with P5.

Zierler:

Did P5 — from the beginning, was there a clear link to the Snowmass meetings? Was it designed to be sort of operated in parallel with Snowmass?

Gilman:

There was a Snowmass meeting as part of the whole process for the Bagger-Barish subpanel. It was a chance for the community to come and talk to the subpanel, and it’s natural that P5 would love to hear from the community as a whole, not just in writing or individual presentations. In fact, the Gilman subpanel’s meetings were planned to be at the major labs and a few universities, with open sessions to get community feedback. Snowmass is another natural way to get both informal and organized input. Now I think it’s in everybody’s brain that, if possible, something like Snowmass is a necessary event as part of the P5 process.

Zierler:

Another autopsy kind of question — why do you think support for ILC fell apart? What happened there?

Gilman:

The ILC (or an equivalent circular machine) remains in the long-range plans of the high-energy physics community globally. As to why, more than twenty years on, there is no construction project, I think comes down primarily to the cost.

Zierler:

Simple as that?

Gilman:

The U.S. would not be host — that possibility got pushed from the 2000s to the next decade and beyond as the U.S. community and successive P5’s saw the DOE HEP program did not even keep up with inflation. It just wasn’t gonna happen here. Still, a significant part of the U.S. community and the labs would be interested in being part of an ILC or equivalent, and it continues to be a part of the global planning for future colliders.

Zierler:

Were there lessons learned or could have been learned from the SSC issue that could have been applied, that would have made ILC sort of viable?

Gilman:

We did learn. A, the ILC was going to be international from the beginning. B, we would have to put together the international collaboration even to do the R&D and have an extensively reviewed design report and cost before we could expect to get it approved by any government. C, an understanding of the experimental program−would you have two detectors or one−and a cost envelope. D, International agreements from the beginning and not done on the fly later on. Those were some lessons learned. The big lesson when you're talking 10 or 20 billion dollars is that the decision is very largely out of the particle physics community’s hands. All kinds of then-current social, political, and economic issues that we talked about before can come into play. You're in contention not only with known issues and forces not under your control, but with issues you sometimes are even unaware of.

Zierler:

Right, right. [laugh]

Gilman:

[laugh]

Zierler:

So another existential question about the status or the state of U.S. particle physics — so just to set the stage, Tevatron is about to complete its scientific program, and there’s a question mark about what happens next with Tevatron. LHC comes online at this point, right?

Gilman:

Right.

Zierler:

Where is the high-energy physics community in response to these things, and the kinds of questions it asked itself about its relevance and its path forward?

Gilman:

There was a debate that went on in the runup to the LHC turning on, as to how long the Tevatron run could actually continue once the LHC started. It went back and forth between people inside Fermilab, the DOE, me, and others. My feeling was that once the LHC is on the air, even if it’s in the early stages, the opening of a new energy regime would so dominate the field that people working on the Tevatron would overwhelmingly vote with their feet and move to the LHC. Therefore, we should strongly focus on finding the Higgs at the Tevatron before the LHC turns on, and correspondingly minimize major shutdowns focused on upgrading one of the detectors. Of course, if you knew that the initial LHC physics run would be delayed, the boundary conditions might change. I also thought that building the BTEV experiment for the Tevatron collider would have provided very interesting B physics and CP violation discoveries that would have kept the Tevatron collider running productively during the LHC’s early years, but that was not to be.

Zierler:

Why?

Gilman:

Because in the end, BTeV was cancelled as part of a decision made by the DOE and announced to HEPAP as the budget for the new fiscal year came out.

Zierler:

Here’s a cause-and-effect kind of question for the beginning of the 21st century. There’s a clear rise or a larger interest in U.S. physics community to both neutrino and cosmological physics. This really becomes a much bigger deal. Do you see the relative standing of high-energy physics as part of that narrative of the rise of these two other major fields in physics, or are these separate narratives as far as you’re concerned?

Gilman:

Not separate. For example, I think of myself as a particle theorist who is now focused mostly on cosmology and its future. Historically, the words high-energy physics came to be the title assigned to the field because the principal tools of particle physics, which once were cosmic rays coupled with emulsions or cloud chambers, had become accelerators coupled with counters or bubble chambers. Experiments done with intense beams at higher and higher energies drove the fantastic progress in our understanding that led to the standard model. Questions such as the nature of dark matter can be approached through cosmology and astrophysics, cryogenic dark matter detectors deep underground, and experiments at accelerators. The nature of dark energy, on the other hand, appears to be a question which is to be answered within cosmology. We should think in terms of having a whole set of tools to find out what the particles and fields in the universe are and their interactions. All that is part of particle physics, by definition.

Zierler:

That’s beautiful. Does it go both ways? Just like we're not going to learn too much about dark energy working with an accelerator, are there things that cannot be understood in cosmology or neutrino physics absent classical high-energy particle physics?

Gilman:

Sure. There’s an example in recent news stories relevant to the question of whether there is CP violation in the lepton sector, which is being explored with neutrino beams. As we’ve discussed, the amount of CP violation observed in the weak interactions of quarks is far too small to account for the dominance of matter in the universe. I don’t see how you determine if it’s coming from the lepton sector just using cosmology. You need to do difficult experiments involving neutrino oscillations that compare neutrinos to antineutrinos and if there’s a difference, how big is it? That is happening at reactors and accelerators.

Zierler:

Now Fred, when you resigned or stepped down from the High-Energy Physics Advisory Panel in 2005, can we read into that larger things about the stage of high-energy physics circa 2005? Or was it simply more a matter of personal decisions and other things that you wanted to work on?

Gilman:

I might have stayed on for a bit if needed to find a new chair. But I had two three-year terms, and I don’t know that anybody ever served more than that. Mel Shochet was the chair after me, and I think he served two three-year terms. It was time to go do something else, which is in fact what I did, in that I then got very much involved in the LSST in the years that followed.

Zierler:

And how did that begin, your involvement in LSST?

Gilman:

The path was again an interesting one. At about the same time that I became the chair of HEPAP, I became the head of the department of physics at Carnegie Mellon. With most of the faculty who had arrived in the decade or two after World War II retiring, it was an opportunity to change in a major way the research portfolio of the department. At the time, each department in the university had an intensive external advisory board visit every five years or so. At Carnegie Mellon, such boards involved both a few members of the Board of Trustees together with prominent academics from other universities, and they reported directly to the CMU president. For the 2001 physics advisory board, instead of doing what had happened often before−proposing hires spread across research areas−we developed a plan focused on three hires in biological physics. The advisory board and then the president and provost backed our plan, and the department carried it out. In early 2007, another advisory board was on tap, and this time, the department’s plan was to make a major move in cosmology, with three additional faculty slots in physics plus three more from retirements on top of the existing astrophysics group. In addition, the department would grow quantum electronics from retirements. Once more, the advisory board strongly endorsed the plan, and the president and the provost agreed. By that summer, faculty searches had begun and the McWilliams Center for Cosmology was born through a major gift from an alum who was on the advisory board.

In the 2007 plan, we emphasized that Carnegie Mellon could bring something special to the table because of our multidisciplinary character and especially the connections that were already growing at CMU between astrophysics, computer science, and statistics in analyzing cosmological data. That drove us to get involved in large cosmological surveys since that’s where the huge data sets were going to come from. Also, we could get involved early on in some major projects and assume important roles from the beginning. The prime example of applying that strategy was the Large Synoptic Survey Telescope, now called the Vera Rubin Observatory, as the ultimate ground-based survey. We soon applied for membership and became the 22nd institution in the LSST Corporation in early 2008, thereby putting our long-lead stake in the ground twenty years out. I became CMU’s representative on the LSST board and soon was on the executive board and deeply involved with many others in trying to make the project a success. It’s a DOE and NSF project that costs about two-thirds of a billion dollars, including the contribution of $30 million by Bill Gates and Charles Simonyi to build the mirrors. The project passed the preliminary design review and became the first priority for a large ground-based project in the decadal survey. Going into the final design, AURA, the Association of Universities for Research in Astronomy, for NSF, and SLAC for DOE took on being the management organizations for construction. From 2012 to 2018 I chaired the AURA/SLAC council overseeing LSST construction, starting with finding a director and a project manager. The project was on cost and schedule and well past the peak in annual funding before Covid struck. Now it’s sitting on top of the mountain in Chile, and hopefully sometime this year the project will get re-baselined. It’s different than turning the whole project back on again as if nothing happened. It’s going to take extra effort now to get the project rolling again and to finish the project with a delay of a year, probably more.

Zierler:

And when it’s back up and running, what are your big hopes and dreams for the project? What do you want to see accomplished?

Gilman:

It’s an amazing scientific project. The basic strategy is to survey the whole sky roughly a thousand times in ten years, creating what is now called the Legacy Survey of Space and Time. Roughly 20 trillion bytes of pictures per night. If you add up all the pictures taken of a particular piece of the sky and superpose them, you see very deeply−for example, 20 billion galaxies−with an 8.4-meter primary mirror and a 3.2 billion pixel camera. It will pin down the properties of dark energy far better and map the dark matter in the universe using weak gravitational lensing. The number of known small objects in the solar system will be multiplied by ten to a hundred to understand much better how our solar system assembled and apply that to planetary systems elsewhere. Ditto for understanding the assembly of the milky way and other galaxies. In short, it’ll have an effect on almost every part of astrophysics and astronomy. However, I still think that the biggest thing that will come from the LSST will be a surprise, which will happen because not only can you superpose pictures, you can also subtract them electronically and see what changed. LSST will find something like ten million transient events a night. Most of them will be mundane, the analogue of peripheral collisions at colliders−known asteroids, comets, variable stars, etc. But buried in those transient events, maybe just a few in a billion when you subtract pictures, you could discover something never seen before. While we didn’t know it when construction started, we now routinely observe gravitational waves and have entered the era of multi-messenger astronomy. LSST is a perfect partner to LIGO and/or x-ray or radio astronomy observatories either by finding the transient event itself or by supplying its recent history.

Zierler:

Now, are you letting your imagination run wild? Like if I were to ask you what are the things you'd be surprised to see, are you talking in terms of these are just new categories to science, or you don’t even know what it is that you're willing to be surprised about?

Gilman:

Possibly new science, like learning something major and unexpected about dark matter or dark energy. Possibly observing astronomical objects or situations that we didn’t know existed. Best would be something no one has thought about before.

Zierler:

Who are some of your major collaborators on this project?

Gilman:

At the top level is NSF collaborating with DOE, and one layer down it is AURA collaborating with SLAC. That’s an important achievement in itself which bodes well for US science in the future. Then there is the large set of universities and labs collaborating in the LSST Corporation, which is leading the way to get private funding for the science. Each of the science research topics has an associated science collaboration, the biggest of all being the Dark Energy Science Collaboration, which now involves roughly a thousand people worldwide. That’s particle physics size, with Rachel Mandelbaum from Carnegie Mellon now spokesperson.

Zierler:

Very cool. Have you found Carnegie Mellon to be a good place, post-SSC? Has that worked out for you?

Gilman:

Great. It has really been a terrific place for me in many ways. When considering what to do after the SSC, the obvious thing was to go back to SLAC, but the words “go back” felt wrong after all the things that I did in Texas and the person that I had become. I wanted to do something else related to academia or possibly even in the private sector. When I first arrived at Carnegie Mellon in 1995, I was quite determined not to have administrative responsibilities, and not to have anything to do directly with the DOE. That lasted in the case of the DOE about — well, less than a year. Pief convinced me to be one of the three senior advisors, along with him and Maury Tigner, who were designated by the DOE to advise the Chinese high-energy physics program under the 1979 US-China Science and Technology Cooperative Agreement. That turned out to be a decade-long adventure together with T.D. Lee that led to a major upgrade of their electron-positron collider to a tau-charm factory. At around the same time Pief roped me into that, the president of CMU got me involved in a component of the CMU strategic plan that was being developed and the provost had me lead an effort through the faculty senate to redo CMU’s retirement plans. As recounted earlier, by ’99, I was head of the department of physics and became dean of science in 2007. Some of the things that I got to do as dean were to help build cell, developmental, and neurobiology−memories of Cold Spring Harbor−and celebrate with a first-place Putnam team−memories of MSU 50 years earlier. In hindsight now, if I had gone back to SLAC, not only would I not have done all the university-related activities that I did at CMU, but I doubt that I would ever have been chair of a HEPAP subpanel or chair of HEPAP itself. While I might well have been the same person with the same approach to the future of high-energy physics while employed at SLAC, for those outside of SLAC who did not know me personally, I probably would have been looked at with suspicion as another representative of the national laboratories and a supposed adversary of university-PIs. It also made it possible later to take on the roles with the LSST and many of the other activities that I got involved with. There’s a world of things that I never would have done.

Zierler:

Fred, this has been an epic conversation, all the things that we've talked about. I wonder just sort of broadly retrospective — if you ever have opportunity to give advice to young physicists about some perspective — all of the endeavors that you've been involved in, all of the policy initiatives across the country, different institutions — what are some of the major lessons you've learned over the course of your career, both in terms of doing physics the right way, and in terms of academic service to your community?

Gilman:

The biggest things are to follow your heart, what you're passionate about, and to take risks, which come with the chance that you could fail. Then you will have to learn to pick yourself up and try again, often using part of what you have learned in failing to succeed the next time. This country is much better than most in allowing you to fail and still have an opportunity to try again. After I came to Carnegie Mellon and was pulled into strategic planning, the dean of the business school said that undergraduates at that time would work for perhaps ten different companies in their life. My instant reaction was to recall the career paths of my parents’ generation and many from my own generation, and to think “that’s crazy.” Then I realized that my oldest two children already had three or four employers. It’s a different world. Don’t be afraid to transition to do something different, especially to see where the world is going and become part of it. One more important thing that has been critical for me and which underlies all the rest, is to have a loving partner and family. They and the links from generation to generation provide stability and immense satisfaction when what you give and receive go well. Their support can carry you a very long way when things get difficult and your career isn't going well.

Zierler:

Fred, we talked about this before our official interview today. Today is a very significant day in the world of Black Lives Matters and ShutDownSTEM. I wonder if you have any thoughts to share about how physics as a community can do its part to finding solutions to these incredibly complex and systemic societal problems, in terms of representation of African Americans in physics, celebrating the work of African Americans in physics, and encouraging young African Americans that physics is just as much a field for them as it is for anybody else. I wonder if you have any perspectives to share in that regard.

Gilman:

I don’t know that I have something to offer which others haven't said. I listened at the AAAS meeting in February to the report on African American undergraduate students in physics. I knew from being dean that 50% of the PhDs in biology are now women, while physics has the lowest percentage of women in the sciences and a very low percentage of African Americans. I should read the report in detail — but it’s clear that there’s something about physics that makes it unwelcoming to way too many African American students, even more unwelcoming at this point than for other minorities or for women. There was a time in which being a physics student was very unforgiving for some. I have even seen those who survived their own trial by fire then turn to the next generation and treat them the same way. That’s changed in many places, but we still have a lot of work to do. The APS or AIP study makes that very clear−I don’t remember the name of the person who chaired it and who talked at the AAAS meeting.

Zierler:

Would this be the TEAM-UP report?

Gilman:

Yes, I think so —

Zierler:

That’s probably Arlene Knowles of AIP who you're referring to.

Gilman:

Right. I think it’s AIP and TEAM-UP. I’m curious about your insights and something that I should read in addition to the report to understand how to change things.

Zierler:

Well, I think we're incredibly proud of the TEAM-UP report, and we understand that this is a major issue. This obviously is something that was a major issue before last week. As I said, these are systemic problems. And my observation with what’s going on today is it’s just beautiful — it’s beautiful to see how the physics community is rallying around this cause, and it recognizes that science obviously is not immune — even though the data might be objective, it’s a fundamentally human endeavor, and we're not immune to many of the problems in society at large. So I think there’s a wealth of information and insight, and even a game plan, in terms of what the TEAM-UP report has to offer. And I would hope that one of the outcomes of a day like today is that more people become aware of it, and more people appreciate the things that we can all do.

Gilman:

One of the things that had a big effect on me was reading a book that was in my father’s bookcase by Richard Wright called Black Boy. Have you ever read it?

Zierler:

I know of it. I have not read it.

Gilman:

Preparing for today, I bought it and it was delivered yesterday from Amazon, the 75th anniversary edition. I read it early in high school. I remember the horror of his life-threatening experiences growing up in the South, and what it meant to be a black writer in Chicago as an adult. While I grew up in the very white community of East Lansing, Michigan, I had a very different exposure to the depth of the racial inequities in America because of my father’s role as assistant director of corrections. In particular, in the prisons at that time both white supremacist groups and the Nation of Islam were growing in importance, including physical attacks. I flash back immediately on an incident involving my father, when he was deputy warden. One role of the deputy warden was to be Mr. Security, and the person who meted out disciplinary punishments. A white supremacist prisoner attacked a black prisoner in the prison yard. In the disciplinary hearing, the guards’ testimony was clear as to who was the instigator. In such situations, both inmates often got the same punishment irrespective of fault, but my father gave the black inmate a short time in solitary confinement, and a much longer time to the white prisoner. Word of this spread rapidly, as you might guess. As deputy warden, my father went out in the prison yard along with some guards, and a few weeks later he noticed that there was a white prisoner who seemed to be circling around him, so he walked into the middle of a bunch of black prisoners. That probably saved his life, because afterwards they were able to identify who the guy was and raided his cell, where they found an improvised knife, whose blade had been stolen from the kitchen. When my brother passed away a couple of years ago, Barbara and I went to Ann Arbor to clean out the house and found the knife with the crudely taped-on handle at the bottom of a drawer.

Zierler:

Wow.

Gilman:

As I told you, I have some unusual experiences.

Zierler:

Fred, I think I've got one last question for you, to wrap up this epic discussion that we have had. First of all, I want to thank you, on record, for your extraordinary generosity in spending all of this time with me, for your encyclopedic knowledge of — it’s really a grand tour of physics of the past 50, 60 years. And as a matter of adding to the historical record, it’s just immeasurable what you've contributed, so thank you very much for that.

Gilman:

Well, thank you, and thank you for the compliment on my memories of events and people.

Zierler:

Fred, looking toward the future, what are you excited about, personally? What are you excited about for yourself in terms of what you want to accomplish, and what are you excited about in terms of where physics goes from here?

Gilman:

First, as we've talked about, in a few years, the Vera Rubin Observatory hopefully comes on the air — I'm very anxious to see some of the discoveries that come from it. That’s probably number one scientifically, partly because my heart and work are so invested in it. I would like to see Carnegie Mellon as a leading place for the connection of physics to other disciplines, particularly computer science, statistics, materials science, and biology. Back to our conversation about African Americans and other minorities and women in physics, a piece of a strategy to broaden the participants in physics is to make connections to different parts of science and technology where there is a much broader set of participants than there are in physics. Finally, changing the core education for science students was a major focus of my time as dean of science. I got to work on that with a very talented group, mostly women, from all levels of the university both in science and in the science of learning. Although deep knowledge in a particular discipline is a first component, from the day you walk in the door of the university we try to make the students see a bigger picture as a scholar and professional, understand the frontier of knowledge in other disciples, work together across disciplines, and then couple that with growing as a person and as a citizen broadly. Perhaps it’s the science students who get their education at CMU who will be where I made my greatest impact.

Zierler:

Well, Fred, on that note, again, it has been a delight spending all of this time with you, and I wish you the best as you continue. I see a developing theme is physicists never retire. I love it. It’s just —

Gilman:

[laugh]

Zierler:

It’s amazing! You just keep going, no matter what. And you certainly embody that, and I wish you a tremendous amount of success in your future endeavors. And again, thank you so much.

Gilman:

Well, thank you. And I'll look forward to the transcript and making some improvements.

Zierler:

That’s it! OK.