Marjorie Shapiro

Notice: We are in the process of migrating Oral History Interview metadata to this new version of our website.

During this migration, the following fields associated with interviews may be incomplete: Institutions, Additional Persons, and Subjects. Our Browse Subjects feature is also affected by this migration.

We encourage researchers to utilize the full-text search on this page to navigate our oral histories or to use our catalog to locate oral history interviews by keyword.

Please contact [email protected] with any feedback.

ORAL HISTORIES
Marjorie Shapiro

Courtesy: Marjorie Shapiro

Interviewed by
David Zierler
Interview date
Location
Video conference
Disclaimer text

This transcript may not be quoted, reproduced or redistributed in whole or in part by any means except with the written permission of the American Institute of Physics.

This transcript is based on a tape-recorded interview deposited at the Center for History of Physics of the American Institute of Physics. The AIP's interviews have generally been transcribed from tape, edited by the interviewer for clarity, and then further edited by the interviewee. If this interview is important to you, you should consult earlier versions of the transcript or listen to the original tape. For many interviews, the AIP retains substantial files with further information about the interviewee and the interview itself. Please contact us for information about accessing these materials.

Please bear in mind that: 1) This material is a transcript of the spoken word rather than a literary product; 2) An interview must be read with the awareness that different people's memories about an event will often differ, and that memories can change with time for many reasons including subsequent experiences, interactions with others, and one's feelings about an event. Disclaimer: This transcript was scanned from a typescript, introducing occasional spelling errors. The original typescript is available.

In footnotes or endnotes please cite AIP interviews like this:

Interview of Marjorie Shapiro by David Zierler on May 10, 2021,
Niels Bohr Library & Archives, American Institute of Physics,
College Park, MD USA,
www.aip.org/history-programs/niels-bohr-library/oral-histories/46819

For multiple citations, "AIP" is the preferred abbreviation for the location.

In this interview, David Zierler, Oral Historian for AIP, interviews Marjorie Shapiro, Professor of Physics at UC Berkeley and Faculty Senior Scientist at Lawrence Berkeley National Laboratory. Shapiro describes the value of this dual affiliation and she surveys the current state of play at the LHC and its work on dark matter research, and what physics beyond the Standard Model might look like. She recounts her upbringing in Brooklyn and her father’s work as a medical physicist, and she explains the opportunities that led to her undergraduate admission at Harvard. Shapiro describes her immediate attraction to experimental particle physics and some of the challenges she faced as a woman. She explains her decision to go to Berkeley for graduate school, where the Lab was a specific draw and where she worked under the direction of Dave Nygren, whose group was working on the Time Projection Chamber. Shapiro describes her postdoctoral appointment back at Harvard to work on the CDF collaboration with Roy Schwitters, who was CDF spokesman at the time. She explains the exciting discoveries at Fermilab, her involvement in B physics, and the friendly competition with DZero. Shapiro explains that her first faculty appointment at Harvard was never something that she assumed would be long term, and the circumstances leading to her appointment at Berkeley. She explains Berkeley’s pivot to CERN following the cancellation of the SSC and the trajectory of the ATLAS program to study electroweak symmetry breaking, and she discusses her advisory work on HEPAP. Shapiro narrates the buildup and elation surrounding the discovery of the Higgs and she describes her accomplishments as the first woman to chair the Department of Physics at Berkeley. She discusses her post-Higgs concentration on SUSY and she explains that in addition to pursuing physics beyond the Standard Model and why the LHC data suggests that there remains much to be learned within the Standard Model. At the end of the interview, Shapiro explains why there remains fundamental unanswered questions on CP violation, and she explains why young physicists should pursue their research in the broadest possible way.

Transcript

Zierler:

This is David Zierler, oral historian for the American Institute of Physics. It is May 10th, 2021. I'm so happy to be here with Professor Marjorie D. Shapiro. Marjorie, it's great to see you. Thank you so much for joining me today.

Shapiro:

Thanks for inviting me to be part of the project.

Zierler:

Marjorie, to start, will you please tell me your titles and institutional affiliations, and you'll notice I pluralized that because I know you have more than one.

Shapiro:

Right. So my title is Professor of Physics at University of California Berkeley, and I also hold a Faculty Senior Scientist appointment at Lawrence Berkeley Laboratory.

Zierler:

Now, what exactly is the interplay in terms of your responsibilities between the lab and the department?

Shapiro:

I am a full-time faculty member at UC Berkeley. That means I teach both semesters every year. I have all the normal responsibilities of a faculty member, but my research is in experimental particle physics and the group that I work with is based at Lawrence Berkeley Lab. So, in addition to the three faculty that are on the experiment I work on, there's a very large team of scientists at LBL who are our collaborators, and we function as one group from the point of view of planning. The DOE grant that supports the whole group, including graduate student researchers, goes through LBL; so it really is one joint group.

Zierler:

Marjorie, a question we're all dealing with right now, how has your science been affected one way or the other in terms of the pandemic in this year plus, particularly in the field of experimental particle physics where there's obviously a need for a physical presence, that you can't just do everything with a pen and paper like the theorists can?

Shapiro:

Well, actually I would say experimental particle physicists are probably better able to deal with this than most other fields for a number of reasons. First of all, we're used to collaborating remotely. The experiment I work on is at CERN in Geneva, Switzerland, and because I am faculty that means during the semester it's very difficult for me to get away. If I do take a trip, it's a one-week trip. So for at least the last 10 years the majority of my interactions with my collaborators have been remote. It requires a different set of skills. You have to be able to listen for things that you would usually see, because even when you're doing something that has video, when you're in a view room with 20 or 30 people in different places, you can't see those visual cues. But I think we've gotten pretty good at that. It's been very difficult for people who are trying to build new equipment because they often can’t be present in the lab, and even when they're there they can't be in close proximity with other people. And so it has been hard for them. Most of my work is software and analysis related, so at least I can function remotely. I worry a lot about the students and postdocs because the interpersonal interactions are such a large part of what they do.

Zierler:

Mm-hmm.

Shapiro:

And I would say it really is very dependent on both the individual and the individual circumstances. I have some students who've really been fine, other students who've really been struggling with how to keep focused when they don't see people in person regularly. And so trying to make sure that we have good communications when we're not physically in the same place requires a real effort and constantly reminding people that they need to take time off. Just because they're working at home doesn't mean they're expected to work 7 days a week, 12 or 14 hours a day. You do have to be more careful to make sure that people are functioning. But in some ways, we're lucky because we're at a point where we have a large data set and so we can continue to analyze that data set remotely.

Zierler:

And at the lab what's the scene right now in terms of getting back to normal or whatever the new normal might look like?

Shapiro:

Right. We're really in a transition phase. Up until now the lab has been following very strict protocols, so only about 20% of the normal lab employees are in it at any given point in time. They, of course, are requiring social distancing, masking, one person per office rather than the normal shared offices. And again, the emphasis has been on getting people into the lab who need to be there for their work. So anybody who can work remotely has been discouraged from coming in just because we want to save those spots for the people who have to be there. For example, my office is being used by one of our postdocs who's working on construction tasks and needs to be at the lab and usually shares an office with three other people and can't do that during the pandemic. So I've said I really don't need to be there until August. But it's changing fast. California has been pretty good about vaccinating, so at this point most of the people who are in our group have been vaccinated. Now we're starting to talk about when will we be allowed to be in one place.

Zierler:

Mm-hmm, mm-hmm.

Shapiro:

University of California is talking about in-person classes again in the fall, so I'm really looking forward to that.

Zierler:

Yeah, as is everybody. It's about time. [laugh]

Shapiro:

Yep. Teaching remotely is not easy.

Zierler:

No, it is not. I teach myself and it is difficult, indeed. I'm looking forward to getting back. Marjorie, just for a snapshot in where we are right now, what's going on in experimental physics in your collaborations that's exciting right now? What are some of the big things that are happening?

Shapiro:

Of course, I'm an experimental particle physicist. I work at the Large Hadron Collider. In the first run we, of course, hoped we would see something really new. At the moment, the only thing that we've seen that's new is something that was not unexpected, the Higgs boson. We've gone from a place where we're really doing a looking for new particles directly to a stage where we're trying to understand whether we can see the hints of new particles that are too heavy to produce directly through their indirect effects on things that we can measure well. That's called a precision measurement phase. And so you look at things that have very good ability to calculate, you try and see the effect of virtual diagrams in the processes. The poster child right now is the g-2 at Fermilab where nobody believes that means quantum electrodynamics is wrong. What they believe is if that measurement does disagree with the calculations there's something else running around in loops; there might be a hint of new heavy physics. Of course, we don't know yet whether that result is going to continue. There's some disagreements on the theory side as to how large the discrepancy is, but it's an example of the type of thing that you can do with indirect measurements. The other area that I think is very exciting now is dark matter, where we know there is something. There's no question that there is dark matter. And there's a large possibility that whatever the dark matter is will be something that addresses particle physics questions. And so that's a very broad-based program that involves people working on cosmology, people doing direct detection with underground experiments, and people like me working at the Large Hadron Collider who are trying to produce dark matter particles in the collisions of protons. The hope would be to see it in two places and then you can ask is it the same thing you're seeing in both.

Zierler:

If we don't know what dark matter is then how do we know how to look for it at the LHC?

Shapiro:

Well, there are different theories of what dark matter is, and each of those theories has its own signature. And so you start with the most general things. Dark matter doesn't interact, so you look for cases where there's an apparent missing momentum because no one believes, again, that momentum conservation won't work. If they see missing momentum, that means there's something that's escaping without interacting and your particle doesn't see it. It seems to be recoiling against nothing because something's escaped. There's a very large effort to look for different types of events that show evidence of something escaping the detector without being seen. Now, of course, neutrinos do that, so you have fundamental backgrounds from processes that include neutrinos, and the question is to find places where you have the potential to see an excess over what you would expect from neutrinos and demonstrate that the excess is convincing. The problem is you don't have a very nice peak because, since you're not seeing something, you basically see a recoil against nothing, so it's not like looking for a new particle by seeing a bump in the invariant mass. You have to really convince yourself that you understand the backgrounds because you're looking for an excess in something without a peak. That's probably the fundamental and most general way to do it. Different theories give different predictions for specific processes, and so once you've done the generic search, which gives you a broad-brush look, then you ask, are there cases where it could be there where we would've missed it in that generic search? And then you're basically filling in the holes in the detection capability. And so it's a combination of doing both of those.

Zierler:

Marjorie, a really broad question, but given the amount of guidance that you and your colleagues in experimental particle physics enjoyed in the search for the Higgs in the run-up, 2011, 2012—

Shapiro:

Right.

Zierler:

—just to bring that up to where we are now in 2021, what guidance are theorists providing to you and your colleagues in the world of experimentation at LHC?

Shapiro:

It's a very different world. Before the LHC turned on, many of us had a prejudice that supersymmetry was going to be the correct theory, and that the supersymmetric particles were light enough that we would produce them at very high rate in the LHC. And so there was a tendency to design the initial searches in a way that really emphasized that type of theory because we were getting lots of guidance from many parts of the theory that this solution might be correct, including the fact that supersymmetry gives you a natural dark matter candidate. Also, supersymmetry says the lightest Higgs looks like the standard model Higgs, so seeing something at 125 GeV is not insane. It's a little heavier than most SUSY models would want but it's not crazy. At this point, the simplest SUSY models have pretty much been ruled out for the LHC regime. It doesn't mean SUSY is dead, but it either means SUSY particles are heavier than we thought, or it means the model is more complicated than we thought, and that makes it less compelling. So I would say at this point there's lots of potential new physics. There isn't the same kind of a frontrunner that there was at the turn on of the LHC. So there's pluses and minuses to that. The pluses, there's lots of things to look for. It's pretty democratic. There's no favorite model. That means it's great for students because each one of these models is a thesis with a potential to be a Nobel Prize if it turns out that model is correct. But the chance of any one model being right is small, and so most of those searches end up being limits, saying this model does not exist within this parameter range. And for some people, that's a lot of fun because they're really looking for something new. For other people, it's very discouraging because you're not finding anything. It's a different way of looking. And to some extent, now that we know the lay of the land, what we're trying to do is really ask, how well can we constrain the physics we know about and see small deviations from that and believe those deviations are real? If you turn on and you see humongous signals, then there's no question it's real. You may not know what it is, but there's something new there. If you're looking for something that's more subtle, then convincing yourself and the rest of the community that it's real requires a much deeper understanding of all of the physics that we know is there so that we can really argue that anything that we see isn't just the tail of some distribution that we know about. And so it's putting a lot more pressure on the theorists to be able to do very detailed calculations, and a lot more pressure on us as experimentalists to be able to both know things at high precision and to be able to convince everybody that we know them at the precision we claim we have.

Zierler:

Marjorie, to the extent that all of these questions at the LHC revolve around the idea that the LHC obviously is not operating at the energies that were envisioned for the SSC before it was canceled—

Shapiro:

Right.

Zierler:

—or even the ILC, to what extent do we need those advances for these fundamental questions that you're after that might not be answerable at CERN in its current setup?

Shapiro:

Well, I think at this point everything we've seen tells us that the SSC was the right machine to build. You did not need it for the Higgs, which we thought we might. But for the new physics, the fact that we haven't seen anything yet would've been a much more compelling argument at the SSC energies. But that's a battle that's been won and lost.

Zierler:

Are you referring specifically to supersymmetry or something else?

Shapiro:

Well, I would say the fact that we haven't seen any new physics, whether it's supersymmetry or extra gauge, bosons, 30 TeV is a much bigger window for new physics than 13 or 14 TeV, so it would've had a much larger discovery window. No one, of course, knows whether or not there is anything new in those regimes. One of the problems and one of the real challenges in putting together the case for the next accelerator is that we don't yet have any smoking gun that tells us what the right next place to look is. And that's, again, something I was not expecting. I thought by this point in the LHC I thought we would be really seeing something new, not just the standard model Higgs; but also that if we didn't see anything that was compelling, we would at least have hints that would tell us this is the next thing we need to do in order to test the model. And so far, the agreements with the calculations have been so spectacularly good that there is no obvious next pointing to what the machine should be. And there's not the same kind of no-lose theorem that we had before the LHC was built or that we always talked about in the SSC days, where we knew that electroweak symmetry breaking had to have physical effects that we could see at the LHC independent of what the model of electroweak symmetry breaking was. There is no no-lose theorem anymore. So that means it's a much harder problem. It means that the case will take longer to develop, and we need to really look carefully at what the right next machine should be. I think it puts more pressure on the accelerator builders to really improve technologies because, as somebody once said to me, if you're fishing you better have a long pole.

Zierler:

[laugh]

Shapiro:

And that's kind of where we are, right? You don't want to build a machine that has 30% more energy than you have now when you don't know what the next scale is. If you can double the energy or triple the energy, then there's a real potential to see something new. Small increments, unless you're very lucky, probably aren't going to buy you that much. So the Snowmass process [Snowmass is the US particle physics strategy process]is going to be a complicated and difficult one.

Zierler:

Marjorie, maybe this is more of a nomenclature question than a scientific question, but you can answer it either way. Do you see where we are now as continuing to build out the standard model that we currently have, or are the things that you're talking about by definition mean new physics beyond the standard model? Where are those distinctions for this moment that we find ourselves in post Higgs?

Shapiro:

Yeah. The distinctions are, I think, subtle at this point, again because we're in a stage where we're looking indirectly at small standard model effects. But I would say what's always excited me about particle physics is trying to get to the next level and to find the things that are really new. So if I ask what I would want to be doing next, it really would be asking, where do we have the greatest chance to find something that doesn't fit within the standard model? That's why experiments like neutrinoless double beta decay that can really ask the question“Are neutrinos their own antiparticles?” are compelling, This is something that would be outside the standard model by definition. Proton decay, which would be an indication that grand unified models might be right. Large increases in energy which have a potential to produce particles that we've never seen before, or any experiments that are sensitive to dark matter, either by producing it, for example, in a collider or looking for axions using techniques that are traditionally more condensed matter AMO-like or more cosmology-like, all of those, in my view, are really the things that are going to push us forward. One thing that I think is becoming more and more true is we have to be less dependent on one specific technique. When I was growing up in the field, people believed building the highest energy accelerator you could was the only way that you were going to move forward. And I think that really isn't the case now. And so it's interesting because it's providing much more interaction with physicists who are in areas that traditionally particle physicists didn't interact very much with. So, for example, atomic physicists. If you're really going to be trying to do precision tests, something like the electron to dipole moment will be addressed using atomic-physics-type techniques, not standard-particle-physics-type techniques. The neutron dipole moment, again, uses a much more nuclear physics technique. So when I work with my graduate students I to try and make them really believe that you shouldn't be married to a technique, you should be married to wanting to push whatever you need to to get the most exciting science. And that might mean every few years you have to retool what you have to do, and that's life, right? [laugh]

Zierler:

Well, Marjorie, let's take it all the way back to the beginning. Let's start first with your parents. Tell me a little bit about them and where they're from.

Shapiro:

OK. So I grew up in Brooklyn, New York. My mom was an elementary school teacher. My dad actually was a medical physicist, which, it turns out, is not so unusual among women in physics, at least in my generation. There were very few women in physics, and the fraction of them that had at least one parent who was a scientist was surprisingly large.

Zierler:

What was your dad's technical background? Where did he go to school? What did he study?

Shapiro:

He went to Brooklyn College, then was drafted into the military. He was in World War II. And at the end of World War II under the GI bill, he spent six months at the Sorbonne which, for him, was an incredible revelation, and probably had a big influence in me because one of the lecturers of the Sorbonne when he was there was Irène Curie. And he came away certainly saying, "She was the best scientist I ever knew." So the idea that women didn't do science was something that never was part of my background. [laugh]

Zierler:

Are your parents native New Yorkers?

Shapiro:

They were. Yeah, they both grew up in Brooklyn, too.

Zierler:

And where in Brooklyn did you grow up?

Shapiro:

I grew up sort of the edge between Flatbush and Midwood.

Zierler:

OK.

Shapiro:

So I went to Midwood High School.

Zierler:

OK. I can get more specific than that. I know that area pretty well. My mom is from East 3rd between I and J.

Shapiro:

OK. Very close. So I grew up on a tiny street called Waldorf Court which is right off Rugby Road, which is what East 14th Street changes to after Avenue H.

Zierler:

Uh-huh, uh-huh.

Shapiro:

On what was then the D train, and I guess now is the M.

Zierler:

Very nice. The old country.

Shapiro:

Yeah. [laugh] Yeah, it was.

Zierler:

Did your father encourage you specifically to go into science and even more specifically physics? SHAPIRO: Yes and no. He never told me I should be a scientist, but he always taught me to think like one, without my even realizing that was happening. He used to like to sail. He had a little sailboat in Sheepshead Bay, and he used to take me out sailing. And whenever he went sailing, he would say, "OK. The wind's going in this direction and the tide's going in this direction. Which way do you need to point the boat if you want to get to that point over there?" And when I took my first physics class and learned about vectors, I realized I knew all this stuff because he taught me all about vectors. He never said that they were called vectors, but he definitely taught me that way. And he always made sure that I could explain things. When I'd say something, he'd say, "Well, how do you know that's true?" So for me science was always very natural, and the idea that doing science was explaining science to other people was also very much part of the way that I learned it.

Zierler:

Would you say that you had a strong curriculum in math and science in high school?

Shapiro:

Yeah. I was pretty lucky. Even though Midwood was a public high school, it was quite a good one. So they had AP calculus, AP physics, and so I was fine. I went to Harvard as an undergraduate and, of course, like most people who go to Harvard, there's a little bit of imposter syndrome. When you get there, you feel, what am I doing there; everyone must be smarter than I am.

Zierler:

[laugh]

Shapiro:

But, in fact, it was OK.

Zierler:

Now, was it physics from the beginning? Did you know that's what you wanted to pursue when you got to Harvard?

Shapiro:

By the time I got to Harvard, yeah. When I was in high school, I thought I wanted to be an anthropologist, but by the time I started at Harvard I knew I wanted to do physics. And, again, I was quite lucky because I ended up being in a freshman dorm that had several women who were astronomy majors. And so, even though I was the only one majoring in physics, astronomy and physics took exactly the same curriculum for the first two years and I had a lot of people around who were—well, not a lot—three or four people around who were in my classes who I could really interact with who I knew from the dorms.

Zierler:

Did you have any idea when you got to Harvard all of the exciting things that were happening right at that moment?

Shapiro:

No. No, I didn't. I definitely didn't. I think the first time that I really understood that was when the charm was discovered, because I was an undergraduate when charm was discovered. And the week after the announcement, Shelly Glashow gave colloquium, and it was totally packed.

Zierler:

Yeah.

Shapiro:

And as an undergraduate sitting in that colloquium, I think that was the first time I realized that there was something really special going on. You could just feel it in the room.

Zierler:

Did you remember how Shelly conveyed what a big deal this was?

Shapiro:

He was completely flabbergasted. It just seemed too much. I remember him just saying, "Well, I'm not sure what to say." It wasn't the most polished of presentations, but in some ways, I think that was better because it really showed that this was something for everyone. Again, I know people expected charm, but there's a difference between expecting it and really seeing it.

Zierler:

What challenges might you have experienced as a woman in physics at that time?

Shapiro:

Well, as I say, I was pretty lucky because I did have a cohort of other women around. It is true that there were not very many of us, and I think there was a certain feeling that you had to be able to ignore it in a way that I think women now don't do, and it's better that they don't have to do it. When I was a graduate student, I think it was a probably a bigger issue. There I really did find there were times when there were things that I had to modify. And part of the hard part was figuring out which things you're willing to modify and which you weren't. So, for example, I stopped wearing dresses completely when I was a graduate student. It was a point in time where women wore leotards. I stopped wearing leotard tops when I went to work and started wearing baggy, loose work shirts just because I noticed that, depending on how I dressed, I was really treated differently.

Zierler:

Mm-hmm.

Shapiro:

And I decided that was something I just didn't want to deal with. And again, you could say it's not right, you shouldn't have to do that, but you chose your battles, and that was one I decided not to choose.

Zierler:

Marjorie, who were some of the professors at Harvard who were a mentor to you or who exerted a formative influence on your intellectual development in physics?

Shapiro:

So in terms of particle physics, Larry Sulak, who taught the particle physics class. And probably the reason I became a particle physicist is because he just made you feel there wasn't anything else you could do. It was clearly the most exciting thing, and he was so excited about it that that was it. So he was a major influence. My first year at Harvard I took a freshman seminar with Norman Ramsey, and that was when Fermilab was being built and he was flying to Fermilab every week and he'd come back and he'd say to our freshman seminar, "Well, it looks like the energy's gonna go up a little bit. It looks like the magnets are really doing well." I didn't at the time realize who Norman Ramsey was fully, being a first-year undergraduate, so I didn't realize what an incredible honor it was to have him teaching this seminar. But, again, the excitement was clear. And then, my freshman E&M class, Purcell taught from his book and that was also a pretty amazing experience. [laugh]

Zierler:

[laugh] At what point did you know that it was experiment and not theory that you would focus on?

Shapiro:

Experiment I knew pretty early, much more so than particle physics. Actually, when I came to Berkeley, in spite of the fact that I said Larry Sulak was the reason I became a particle physicist, I still was wavering a little bit, “Should I do condensed matter or particle?” But I always found that I liked building stuff. And in fact, I thought I was going to be a hardware physicist. Once I decided to do particle physics, I really thought I would be someone who would build equipment my whole life. I didn't think I would mainly be doing software and analysis. And when I picked a thesis group—Dave Nygren was my thesis advisor—it really was to build stuff.

Zierler:

Yeah.

Shapiro:

Again, maybe because I'm a woman, it was a slightly different background. I was a little paranoid because I always thought all the male students must've fixed cars when they were kids. Most of them hadn't but I always thought that that's what they must've been doing. I used to weave and paint and things like that, and so I always thought of building stuff as being a creative enterprise, and for me being an experimentalist had a lot to do with building things and the creativity involved in that building.

Zierler:

Did you have any summer laboratory experiences that were useful for you as an undergraduate?

Shapiro:

No. No, I didn't. I worked during the semester for one semester in Tinkham's group, but I was pretty incompetent, to be honest.

Zierler:

What was Tinkham doing at that point?

Shapiro:

I basically followed a postdoc around and watched what they did. It was not an experience where I came away feeling that I was a great experimentalist based on it.

Zierler:

What was Tinkham doing at that point, do you remember?

Shapiro:

They were doing some thin films and a little Josephson junctions, and I hadn't taken a condensed matter course, so I wasn't sure I even understood what they were talking about.

Zierler:

[laugh]

Shapiro:

It was good to see how an experimental group worked, but I really didn't have the knowledge I needed in order to be useful in that group.

Zierler:

Did you get any advice about graduate programs, places to apply, people to work with?

Shapiro:

No. I just looked at what were the places that were supposed to be good and applied to them all, and then visited and decided which one looked like it was a good match.

Zierler:

What was the culture about staying at Harvard or not?

Shapiro:

Well, I knew it wasn't a good idea to stay in the same place.

Zierler:

Mm-hmm.

Shapiro:

I think moving is always good. One of the things that did matter to me is I'm a city person. I went to some of the schools to visit that are in more remote locations and I just thought, I can't live here five years. [laugh] So Berkeley ended up being a good match. I liked the fact that it was big, that it had lots of options, that I could go there not having decided who I wanted to work with and know whatever happened there would be someone.

Zierler:

And was Berkeley labs specifically a draw, you'd be able to do some interesting things there, as well?

Shapiro:

Yeah. Yeah, it was. It was part of there being a very large intellectual community. I knew I didn't want to go to a small place. I wanted to go to places that had lots of stuff happening, and Berkeley was one of the ones that was true.

Zierler:

Was your sense—just to return to an earlier part of our conversation—graduating in 1976 from Harvard—

Shapiro:

Mm-hmm.

Zierler:

—was your sense that the standard model was still wide open, that there was still lots to learn, it was still being built at that point, or did it seem more like the standard model was already completed?

Shapiro:

No, it was definitely not complete. At that point, there were clearly things that we didn't understand. The electroweak part of the theory hadn't been that well tested yet. The strong interaction part of the theory certainly had not been tested then. It was barely taught as being the standard model. It was taught as being strong interactions and electroweak interactions. And at that point, at Berkeley, although QCD really was already obviously the right theory, we still had Geoff Chew around so there were a lot of people who were still saying, well, maybe there's something else there. [laugh] It really was a time when things were happening amazingly fast. The first couple of years I was a graduate student was when the electron parity experiments were being done at SLAC, so that was really precision electroweak in the first sense. And the discovery of the W, which happened while I was graduate school, really was the time when you had to say yes, the theory is real.

Zierler:

And what was going on at Berkeley lab when you first arrived? What were some of the big things happening there?

Shapiro:

So I was a graduate student on the time-projection chamber, the first time-projection chamber at PEP, and so e+e- collisions were really the way to go. Everyone thought at that point that the energy at PEP and PETRA were just going to be high enough that we would see the top. We knew at that point that there needed to be a top. The b-quark was discovered pretty early in my graduate career, and at that point, everyone thought top was around the corner, and everyone thought there would be top spectroscopy. Obviously, people knew about the Higgs from the standard model but that was still a bridge too far. It was really understanding whether you can really understand the QCD given the fact that the theory was not perturbative at the low end, understanding whether precision electroweak with radiative corrections were right, and then filling out the spectrum of quarkonium for the top. Those were the things that people were really most excited about, at least in the collider world which is where I was. Although TPC looks like a small experiment, at the time it was considered a large one, and it was sociologically very different at LBL because it was an experiment that was pioneered by the Young Turks. It didn't come through the old group structure, and the experiment really merged together people who had been in different groups from the early stages of LBL, really pushing to get this new type of detector going.

Zierler:

When did you first meet Dave Nygren?

Shapiro:

When I started looking for a thesis advisor during the Spring of my first year at Berkeley. I knew I had to find somewhere to work for the summer, so I began knocking on doors. And I went up to LBL and knocked on a bunch of doors, and Dave was one of the people I talked to. And again, he was so committed to what he was doing, and it was a chance to get in on something that was really new and was really starting, and for me that was very important.

Zierler:

Which was what? What was he doing then?

Shapiro:

That was when they had already been approved to build the TPC, but they were still in the early prototyping stage. They were trying to really understand how to build it, and so that summer I worked on a wire plane, what was about 4 cm x 4 cm that we were using in order to understand the response of the cathode pads underneath the wires to see what resolution one could get in the R-phi direction using TPCs. It was an undergraduate, two graduate students, and Dave Nygren and a technician, and that was it. And this was the heart of this new detector. So I felt like it was right in the middle of everything. And for me, that really was important.

Zierler:

So from your vantagepoint, what were some of the big research questions that the time projection chamber was designed to answer?

Shapiro:

It's interesting, because at that time I was not yet sophisticated enough to understand what all the big research questions were. I knew that PEP was going to be at a higher energy than the other machines, I knew there was a chance of seeing new quarks, but I don't think I went much beyond that in terms of the science. For me, it was very much at that point in my career Star Trek, a “to go where no one has gone before” moment.

Zierler:

[laugh]

Shapiro:

And the idea that being involved in the new technology would open the new science was for me a lot of the attraction. So it probably wasn't until halfway through my graduate career that I really started to think about, what can we measure, what can we test? And a lot of that came from talking to the postdocs in the group who were trying to think about what they were going to do when the first data came.

Zierler:

When do you feel like you started to get more sophisticated, that you had a sense of what those research questions were?

Shapiro:

Probably towards the end of my graduate career is when I began to, and then as a postdoc I really got thrown into the deep end because I had to answer those questions, not just for myself but for the students. I went back to Harvard for a postdoc, and I was Roy Schwitters' postdoc. And that's when Roy was CDF spokesperson. I was living out at Fermilab, which is also where the graduate students were, and so I was thrown in being the person who represented Roy when he was back at Harvard, and the person who made sure the graduate students were OK. So I had to grow up pretty fast in terms of that, and part of that was being able to figure out what we needed to do next, because, three incredibly smart graduate students that are only a couple of years younger than I was were saying, “Well, what's gonna happen next? How're we gonna do this?” [laugh] I had to act like I knew.

Zierler:

Before we leave Berkeley too quickly, what was Dave's style like as a graduate mentor? Was he hands-on? Did you work closely with him?

Shapiro:

He was, he was hands-on-- well, I didn't work closely with him in the sense of in the lab day to day, because at that point he was doing a lot of trying to put fingers in the dike and hold things together.

Zierler:

Mm-hmm.

Shapiro:

He used to come by the lab at night. I'd come back in the morning and I'd look at my logbook and there would be notes from Dave saying “Why don't you try this? Let's look at that.” And he'd always use a red pen. So I'd come in and it would be this shock to see someone else's handwriting in my logbook. But he clearly was always paying attention. It was a hard time for him because there were lots of difficulties with the TPC, and I think one of the things that really always made me respect Dave was how honest he was with me about that. Halfway through my career as a graduate student, we had a major catastrophe on TPC. The superconducting magnet shorted out and that put a two-year delay into the turning on of the experiment, which for a graduate student can be pretty devastating. And Dave said to me, "All right, this is gonna be at least two years. We have to decide what's best for you. If you want to stay on TPC, we will support you and make sure that you're funded until you're done. If you decide you just don't want to do it, I'll call around and find out what's the best place for you." And Mark II, of course, was ready at PEP, and he said, "I'm happy to call up the Berkeley people on Mark II. I'm sure they could find a place for you. You have to make the decision, but I'll support you in whatever you want to do." And I decided to stay, but I think if Dave had not put it to me that way it would've been very different because I ended up being a graduate student for quite a long time. It was eight years for me to get out because of this two-year delay in the first data taking. And if I'd felt that I didn't have a choice, I probably would have been very resentful. But because I was given options and I felt that it was my decision to take longer so that I could be part of the project I wanted to be on, I never felt trapped by it. And in the end, to be honest, for me it turned out to be good because by the time I got out I had a lot more confidence in my own ability than I would have if I'd done a fast PhD. So I don't think it hurt me. I think it made my career better. But, again, I think Dave's honesty about what's going on and not trying to pretend everything was OK was a huge part of that being a positive rather than a negative experience.

Zierler:

Learning how to problem solve, for example.

Shapiro:

Yep. Yep.

Zierler:

Besides Nygren, who else was on your thesis committee?

Shapiro:

Well, my thesis advisor on paper was Owen Chamberlain because Nygren wasn't faculty and you had to have a co-sponsor who was faculty, and so Owen, who was also on the experiment, was my thesis advisor.

Zierler:

Now, would that mean that anybody who was at the lab could not be the thesis advisor or Nygren did not have the professor title?

Shapiro:

They could be co-advisor, and that's still true now. They can be co-advisor, but you have to have somebody as a member of the Berkeley Academic Senate to be a co-advisor with them.

Zierler:

I see.

Shapiro:

And so Owen played that role.

Zierler:

Now, did you have a relationship with Owen or he just sort of signed his name to your thesis?

Shapiro:

No. He was on the experiment. I had a relationship with him—we didn't talk on a daily or even weekly basis, but he knew what was going on. And I worked very closely with people who were part of Chamberlain group when the old LBL group structure was in place, because I worked with the people who built the prototype for the end caps, the wire chambers for the TPC. And there was this super incredible technician who had been Owen's technician for many, many years who was driving the technical part of that effort. And then the staff scientist who was leading that part of the project was Peter Robrish, who had also been a Chamberlain-Segre student. So the group was very much in the Chamberlain tradition. And the way they taught people about how you to build hardware was very much driven from Chamberlain group. So I always felt that I was part of that whole history, even though I didn't work as directly with Owen.

Zierler:

What was Owen like as a person? Was he accessible? Could you talk to him?

Shapiro:

Oh, incredibly. I mean, he was one of the most accessible—I've met lots of Nobel laureates. They have very different personalities. But he was the most low-key of any Nobel laureate I've ever met. He was very accessible to everybody.

Zierler:

How did the opportunity to work with Roy Schwitters open up as a postdoc for you?

Shapiro:

So Roy gave me a lot of freedom—

Zierler:

But how did you first connect with Roy?

Shapiro:

When I finished my PhD, I applied for postdoc jobs, and one of the places I applied was Harvard. And that was the one I ended up going to. Again, that was when Tevatron was close to turn-on. I started on CDF in the beginning of '85 and the first run of the Tevatron was '87. So it was, again, you can be there on the ground floor. And Roy was a spokesperson, so that made it attractive to work for him.

Zierler:

How much time did you spend in Batavia versus Cambridge?

Shapiro:

Two years. I spent two years in Batavia and then I became junior faculty at Harvard, and that point I moved back to Boston, Cambridge.

Zierler:

What was CDF's status at that point? How far along was it?

Shapiro:

It was in the middle of the construction phase, so when I first got there, I worked on testing calibrations, and then about two years after that, beginning of first data taking.

Zierler:

What were your impressions of Fermilab? What was it like to work there?

Shapiro:

I liked everything about Fermilab except living in the wilds of Illinois. [laugh]

Zierler:

[laugh] This is one of those remote locations you were looking to avoid for graduate school.

Shapiro:

That's right. That's right. Well, I used to go once a week into Chicago, and I think if I couldn't drive to Chicago once a week, I'm not sure I would've survived.

Zierler:

[laugh]

Shapiro:

Every Saturday I'd go into Chicago, I'd have a great day, and then I'd get on the Eisenhower and I'd see the “To Western Suburbs” sign and my stomach would just start to scrunch.

Zierler:

[laugh]

Shapiro:

But at Fermilab, it was a very exciting time. You'd go into the cafeteria at lunchtime, and you'd see all these people waving their hands and talking and lots of different experiments, lots of different things happening. So for me, again, it was being in the center of things.

Zierler:

And what was exciting at CDF at that point? What was happening? What were some of the big research questions?

Shapiro:

So the big research questions: the W had been discovered at UA1 and UA2, but the statistics were quite low on those experiments. Precision measurements of W physics and really understanding QCD (because it was the time when theorists were first beginning to do next-to-leading-order calculations). It was before things had been as automated as they are now in terms of using computational integration techniques. So I remember we were very involved working with the theorists who were calculating the jet cross section to next-to-leading order to understand how do you define a jet? Can we define it in a way where both the theorists and the experimentalists can agree on what we're looking at with a high enough precision that we could see whether the next-to-leading order corrections were right? Search for the top, of course, was a big goal at CDF. And then, the second half of my time at CDF I was very involved in B physics. So it was contemporaneous when the B factories were being built and turned on. But the B factories, of course, did not make Bs, and so Bs mixing was something that was really only accessible in those days at hadron colliders. And convincing the community that we could do that kind of precision physics in the hadron collider environment—in those days people did not think you could measure things precisely in pp collisions, and I think CDF really played a major role in convincing people that hadron colliders were not only discovery machines looking for something really new that then would be explored in e+e-, but that you could do the next stage of the precision work.

Zierler:

Now, obviously, at this stage, no one was talking about closing the Tevatron; this was the height of its glory days?

Shapiro:

When I first started, yes, but by the late '90s the SSC was already on the horizon and the question of what was going to happen to Fermilab when the SSC turned on was a big issue. It was an unsolved problem in the community which unfortunately went away with the SSC dying.

Zierler:

Now, what was your interaction, if at all, with DZero?

Shapiro:

So they were, of course, the friendly competition. I did not have much interaction with DZero during run one of the Tevatron. When we started preparing for run two, I was the project manager for software and computing, and there was a major rewrite of the software and a major change in how one dealt with large data sets. Fermilab computing division, CDF, and DZero were working very closely together to try and come up with common solutions. And so, at that point, I interacted much more with the DZero people, but mainly the people who were involved in computing as opposed to the people who were involved in the physics or the detector side.

Zierler:

Marjorie, what were some of the advances with computers that made this work possible in terms of increased memory and speed and things like that?

Shapiro:

Well, it was a completely different world when I started and, in fact, it very much changed my whole direction as a scientist because, as I say, when I worked for Dave as a graduate student, I always thought I was going to build stuff. That was why I became an experimentalist. That's what I was going to do is I would build new things that would let us do new physics because we had better technology. When I joined CDF, even though it was two years before the experiment was going to start, the hardware was pretty much set in stone. They were already building. There was some work to be done on calibration, but it wasn't an area where you could make a big creative contribution. But the software was a total disaster. I mean, there basically wasn't any software. And so I got there, and I said, well, what can I do to actually make a difference? And it was clear that I could do a lot more on the software side than the hardware side. And I also had a very good software mentor, Dave Quarry, who was the head of software on CDF who really taught me how to approach software the same way I had approached hardware. And he and I did a lot of design work together and figuring out how to put together a software system that could be used by lots of people. In the old days everyone kind of wrote their own. Yes, there was common reconstruction software but after that, everyone did their own thing. And it was clear as the experiments got bigger that was not a particularly productive way to go. And so we wrote what might've been the first particle physics object-oriented software analysis framework, and we had to write it in Fortran in those days. Writing object-oriented software in Fortran is a different experience, but actually was pretty productive. And then, when we got to Run two of the Tevatron, we had a major paradigm shift because we moved from Fortran to C++, which wasn't just changing computing languages but was really changing to an object-oriented approach to software. And then, along with that, having to deal with large, for those days, amounts of data and understanding how to put together a system where you had to have tapes in the background to store the data and ways of moving the data to disks when it was needed, and developing workflows that allowed people to say to the software framework “this is what I am going to do” was very new. Of course, now it's old hat, but in those days, it was very, very new. And I think the other thing which Fermilab really pushed quite rightly and that I was very proud to be involved with was trying to take software to the level that was treated with the same seriousness as hardware, including insisting that during the construction phase for Run two, the software project would be treated like a hardware project. We developed Work-Breakdown summaries, we used Microsoft Project to track milestones and we had resource-loaded schedules. We reviewed our work and progress exactly the same way that the people who were building detector components did. And that was not something that was traditionally done in software at that point.

Zierler:

Marjorie, from your perspective at Fermilab, this was at the height of excitement that the SSC was actually going to be built.

Shapiro:

Mm-hmm.

Zierler:

What was the general reaction? What were people thinking from Fermilab and how might it have affected operations at Fermilab?

Shapiro:

So of course there was a lot of angst because no one knew what was gonna happen at Fermilab if the new accelerator came. I would say there was some division within the community because those of us who worked for universities, many of us just knew that we would move to SSC when it did turn on and we, of course, had the option of doing that. It's clear that Fermilab would have contributed to and played a major role in the SSC experiments, but, of course, it's always difficult going from being an accelerator lab to being a user lab. I don't think that transition ever really fully happened because the SSC died before that stage occurred. But understanding what Fermilab's future would be in an SSC era was just beginning to happen when the SSC died.

Zierler:

Did you have a close working relationship with Roy, or he was too busy, he was not so accessible?

Shapiro:

Well, Roy, of course, was teaching, but he would fly to Fermilab every week. And he really did care about making sure that his group remained a group.

Zierler:

Mm-hmm.

Shapiro:

We had a Thursday night dinner every week, and all the graduate students and postdocs were expected to go to dinner. He had a favorite Chinese restaurant which we went to, not every week but probably half the time. The choice of restaurants was limited at that stage at Fermilab. He did really make sure that he at least had that contact once a week with his group. But, of course, he was very busy, and he expected the next level in his group to be able to take up the slack and let him know when things happened that he had to be involved in.

Zierler:

What were the conversations that led to you joining Harvard faculty, not just as a postdoc?

Shapiro:

Well, those days, to be honest, faculty at Harvard wasn't the same as now. Those were the days when senior faculty—

Zierler:

You mean it was a glorified postdoc as an assistant?

Shapiro:

Yeah, they were glorified postdocs. So it was an honor to be a member of the faculty, but I don't think I ever viewed it as being a long-term position. And, in fact, I think the reason it was a good experience for me is the fact that I viewed it as a glorified postdoc. The people I knew who got very bitter were the ones who thought “I'm gonna be the exception; they're gonna keep me.”

Zierler:

But in your case, at that point, Marjorie, you would've been a double exception because Harvard had never tenured a woman in physics before?

Shapiro:

Nope. That's right. That's exactly right. But to be honest, the fact that I was a woman—I just figured they wouldn't tenure anyone and so I viewed it as being good experience, enjoy yourself, plan to move on before the decision, and don't wait and let them kick you out. [laugh]

Zierler:

Did you ever engage with Howard Georgi on these issues, because he, of course, was very strong about reforming this system and making it more accommodating for women?

Shapiro:

No. I think at that point—it wasn't until afterwards I realized what a true hero he was in that respect.

Zierler:

Yeah.

Shapiro:

At that point, I didn't really even understand. You have to realize, Harvard used to have faculty meetings in the faculty club over lunch, and we'd all eat lunch and then they'd invite the junior faculty to leave before they had the discussion of the business of the faculty meeting, so we were not even allowed to stay during the discussions. So when I got to Berkeley, I remember going to the first faculty meeting where they were discussing a faculty search and they didn't ask me to leave. And I thought, “I'm allowed to stay when they talk about who they're gonna hire?” [laugh] And it was a totally different experience. It was the first time I really felt that I was someplace that expected me to be there forever.

Zierler:

When did you go on the job market again? What indications did you have, or were you proactive about that?

Shapiro:

I was proactive but in a funny way. They were doing a search at Berkeley in particle physics, and I was approached by some of the people who I had known when I was a graduate student and encouraged to apply. So I had not applied anywhere else. But it was an interesting time because I'd already met my husband, who is Ian Hinchliffe, who is senior staff at LBL, but we weren't married then. And so I didn't particularly want anybody at Berkeley to know that we had any involvement, which, again, I think is the difference between now and then. I had to tell the person who approached me because they wanted to ask him to write a letter, and of course he couldn't. [laugh]

Zierler:

Yeah. [laugh]

Shapiro:

But I explicitly asked the faculty member who approached me not to tell the rest of the Berkeley faculty.

Zierler:

Yeah, yeah. Being a graduate student there and the way that you were pretty sophisticated about the culture of not promoting at Harvard, did you have a sense that Berkeley was a very different place, that it was more supportive of its junior faculty?

Shapiro:

Oh, yeah, Berkeley always hired junior faculty with the understanding that if things worked out there was a place for them. It didn't mean everybody got tenure, but the assumption was that if you succeeded you would get tenure. And I think a corollary of that is they put much more work into their junior faculty searches, because Harvard they really did view them as glorified postdocs. They sort of said, well, it's this group's turn. They can decide who it's going to be.

Zierler:

Yeah.

Shapiro:

Because after all, it was somebody who was only going to be there for a few years and as long as they were above some moderate threshold nobody cared.

Zierler:

Now, did you retain all of your collaborations and research at Fermilab during this move? Was that the same?

Shapiro:

Yes. Yes. I stayed on the same experiment.

Zierler:

So what was going on at Fermilab at that point by 1990?

Shapiro:

So 1990 was the beginning of the part of Run one of the Tevatron that had enough data to do a lot. There was search for the top, which I was not involved with although the Berkeley group was; a very big program in understanding QCD and jet production, which I was involved in; and a program involving W production, which, again, there was a big involvement in Berkeley. But my main involvement was first in QCD production and then later on in B physics.

Zierler:

What was the understanding that you reached with Berkeley in terms of balancing teaching, your need to be at Fermilab, how did all of that work out at the beginning?

Shapiro:

I taught a regular schedule. I tried to arrange it so that—so, for example, if I taught a class that was small enough, I could do Monday and Friday, but a lot of times I was teaching Tuesday and Thursday. And when I was doing a Tuesday-Thursday class, I'd get out of my Tuesday class, get on an airplane, fly to Fermilab, spend Wednesday at Fermilab, fly back Wednesday night. Or if I could teach Monday and Friday then I'd have three days there. I was going to Fermilab three weeks out of four and still teaching. I was writing my lectures on airplanes.

Zierler:

So you were pretty busy.

Shapiro:

Sometimes they'd let me teach double one semester, so I didn't have to teach the other semester, and that made life easier.

Zierler:

Tell me about your designation as a Presidential Young Investigator. What does that mean?

Shapiro:

So that was the early version of what's now the career grants. I actually was awarded that while I was still at Harvard but used it when I went to Berkeley. It gives you a little bit of freedom because you have money that you don't have to ask anyone “Can I spend it?” And it's much less prescribed than other grants. So that was nice. I hired a postdoc who worked with me a lot when I was on CDF, so I've always been very grateful to the NSF for providing me that little bit of freedom.

Zierler:

Now, the associate line at Berkeley, is that tenured?

Shapiro:

Yes. But I actually went—I was an associate professor at Harvard. I became an assistant professor again when I came back to Berkeley because it was a lateral move and there is no nontenured associate at Berkeley. So I did not view it as a demotion, even though the title looked like it.

Zierler:

And did you come with the understanding that tenure review would happen pretty quickly at two years?

Shapiro:

Yeah. I came with the understanding that it would happen fairly quickly but that I would need to have demonstrated a record of teaching and have some reasonable level of publications from things that I'd done while I was at Berkeley. But somehow or other, I was naïve enough that I didn't realize that there was a risk there. But again, since I never viewed tenure as something that would happen at Harvard, it wasn't much of a risk.

Zierler:

Right.

Shapiro:

It really was a lateral move.

Zierler:

Right. To go back to an earlier thing we were talking about, by the early 1990s, where was the standard model at that point? Were people starting to talk about new physics, or not yet?

Shapiro:

Well, people always talked about new physics. There were people looking for supersymmetry in the early '90s but I think it was not nearly as much of a discussion as it became 10 years later. There was a lot of discussion about the Higgs, and what was the mass of the Higgs going to be. That, of course, was when LEP was turning on. There were great prospects for seeing the Higgs at LEP. I think we always knew that at the Tevatron it was not impossible, but it was difficult. It was never clear whether or not one would be able to see it there, although there was a significant program to look at it. So I would say really at that point verifying that the standard model worked in the context of loop corrections was probably the most significant part of the collider program, both at the LEP collider and at CDF. So for us, this is your measurement of the W mass, understanding the constraints on the mass of the top and the mass of the Higgs that you got by the ratio of the W mass to the Z mass, understanding whether the things that were being seen at LEP in terms of electroweak corrections could be used at CDF. And again, we were the only place that could make the top, so that was clearly a major part of it. So it really was still putting together the last pieces of the standard model, both in terms of making sure we knew what the building blocks were and verifying that the theory calculations could be done at the accuracy we needed. Those, I think, were probably the big issues. And then, towards the end of the '90s CKM matrix became a major focus. Understanding what you could do both in B physics for constraining the CKM matrix, and then things like looking at top flavor-changing neutral currents to understand whether the top really looked like another normal quark that had CKM couplings was a big part of the program.

Zierler:

Now, in the mid-1980s, I asked you about your sense of the feeling in the community about the rise of the SSC. By the early mid-'90s, what was your sense of the impact of the collapse of the SSC? What did that mean for experimental particle physics in the United States and how might that have affected your involvement at CERN which was coming up?

Shapiro:

Oh, it was devastating. At Berkeley, although we clearly had a program at Fermilab, we had a very large group on SDC, which is one of the LHC experiments. George Trilling was the spokesperson. The LHC design group was centered at Berkeley, so we had a very large involvement in the SSC. I was starting to go down to Texas for meetings and beginning to think about what I was going to do when I transitioned my research. And the death of the SSC really hit everybody incredibly hard. I knew some graduate students who just left, both theory students and experimental students. Probably it was the normal stages of grief here and denial first, and you have to then go through the other stages. And at that point we decided we didn't have a choice. We had to go to CERN, because it was only way we were going to do that physics. And so we took a little bit of time. We looked at Atlas and CMS and talked to both collaborations. And like everyone else in the US, had to make a decision, and in the end—we knew right from the start that Berkeley was going to join one of the experiments and not both. We thought, especially given the distance, it made no sense to work on both.

Zierler:

Yeah. Now, when you came to Berkeley, was it a dual appointment from the beginning or you took on the affiliation with Berkeley lab later on?

Shapiro:

My nine-month salary always came from campus and my summer salary always came from LBL, and that was true from the beginning, because my summer salary came from the research grant and the particle physics research grants were all administrated through LBL.

Zierler:

Did you have a chance to work with George Trilling directly ever?

Shapiro:

Yeah. Yeah. George I worked with a lot, both on SDC and when we first were talking about ATLAS. And I always considered George a friend. George and his wife Maya were both people we saw socially.

Zierler:

How did Berkeley get involved with CERN to begin with? What were the mechanisms that made this collaboration possible?

Shapiro:

So, again, the whole US particle physics community was doing this at the same time. We were very lucky because CERN was willing to talk to us. I think CERN understood they needed both the person power, and the US finances. Even though we were not going to make the kind of contributions that would have been made for SSC, it was clear that there were significant financial resources, as well as people resources. So there were high-level negotiations between the DOE and the NSF and CERN, and in parallel all of the individual groups deciding how they were going to organize. We went to CERN, we talked to people, we compared what we would be doing in the two cases. We had some fairly strong ties with some of the ATLAS people because there were several members of the LBL group who had been at CERN. Jim Siegrist, of course had been on UA2, and Kevin Einsweller had been on UA2, and Peter Jenni was the ATLAS spokesperson and he'd been UA2, so we had strong personal ties there. And that had some influence, and I think also, looking at the general organization of the two experiments we saw an easier place where we would fit in on ATLAS. Right from the beginning, the ATLAS groups decided that they were not going to build US pieces of the experiment and bring them over, so we integrated all of the US groups into the collaboration as a whole. So we worked very much closely with UK groups, Japanese groups, and German groups on the tracking detectors for LHC.

Zierler:

Marjorie, I'm curious the extent to which your advisory work first for the National Research Council and then later on for HEPAP for the Department of Energy, how might that have informed these top-line high-level negotiations between the National Laboratory System bringing their expertise to CERN?

Shapiro:

So I think the roles we played there were more roles to articulate the science case. So they weren't nitty gritty roles in terms of negotiating how money and people would work, but, of course, after the death of the SSC, it was important to make a case to Congress that the science needed to go on and that we needed to find a way to do it within the budget constraints that US Congress is willing to consider.

Zierler:

And was it also important to convey that post SSC CERN is the only game in town, on the planet really?

Shapiro:

Well, first you have to convince them that you want to be in the game.

Zierler:

Yeah.

Shapiro:

So at that point, there was a feeling among many people that the government may have decided that particle physics was something the US could opt out of. So I think our primary concern was, first of all, conveying how important we thought the research was, what role particle physics would play itself and through its interactions with cosmology and understanding the universe, how to make a credible and correct case for its interactions with the rest of science, because we did not want to say things that either weren't true or that were misleading. We did not want to pretend that spin-offs were the reason we were doing this, but we wanted to point out that the intellectual activities are important to maintain the kind of scientific course that the US wants. And so I think our role was really articulating the importance of the science and then trying to both prioritize the science questions and to map the science questions onto facilities that could be built, and that the US could play a role in.

Zierler:

Now to clarify, was Berkeley facing a binary choice between ATLAS and CMS? In other words, could it have sent some scientists to one and some to the other?

Shapiro:

In principle we could have, but we decided very early as at the Berkeley group that we wanted to move to one experiment. We had been, in the Tevatron days, both on CDF and DZero and had quite strong groups on both of those. But that was some place where you could get on an airplane and take a four-hour plane ride and go there every other week or even two weeks out of three. CERN we knew was going to be different, and we felt, if we were going to be able to play the kind of role especially that you want a national lab to play on an experiment like that, dividing ourselves into pieces was a bad idea. So the first decision we made is we are not gonna be on both experiments. And then we had to decide which one.

Zierler:

What were the considerations, given the fact that CMS and ATLAS had elements of competition and collaboration?

Shapiro:

Yeah. So I don't think there would've been a wrong answer. I think if we'd made another decision, it would've been fine. I think we had some sympathy with some of the design decisions that were made in ATLAS. We liked the organizational structure. It was clearer, at that point in time, what roles we as a group could play that the collaboration needed. You want to go somewhere where you're needed and where you can really play an important role. And the lab had very strong engineering IC (Integrated Circuit) design capabilities, and good mechanical capabilities, as well as being able to be a strong construction site, so we wanted to go somewhere where those things would be used and considered an important part of what we were bringing. It was also clear at that point that we wanted to play a role in the software design, and it just seemed to be a good match, both in terms of our interactions with the people and having the right skills. And, again, I think it could have gone the other way. It wasn't as if we said “Oh, one experiment's good; one experiment's bad.” We had to make a choice and we did. And I don't think we've ever regretted the choice.

Zierler:

And so why ATLAS given how similar the considerations were?

Shapiro:

Um ...

Zierler:

In other words, it a great way of understanding, like, what is the difference between ATLAS and CMS, because there are, and you do have to make these choices; so what are they?

Shapiro:

So I would say a lot of it was the organization of the projects. We wanted to be fully integrated with CERN. We did not want to—it was clear at the beginning that on CMS the US groups on CMS were deciding the were gonna build certain things and bring them, which is, in some ways, a great thing to do because it means you, by definition, have things that you own and you're bringing in to make you an equal member of the collaboration. But I think we were very attracted to a model where we were more part of the CERN experiment rather than an outpost, and that meshed well. Again, we had very strong relationships with a number of people on the experiment who were in the management and the structure. We knew that we could work well with them. I would say it probably was not primarily based on looking at the design of the two detectors and say we like one detector design better than the other. But, again, I want to make clear that I have a lot of respect for my colleagues on CMS. It was not a case of thinking anything bad about them.

Zierler:

Certainly.

Shapiro:

It was more a case that we found a place where it felt like home.

Zierler:

So what year was it that Berkeley formally joined ATLAS?

Shapiro:

I think it was '93. I'd have to double check, but I think it was '93.

Zierler:

OK. And what were the big questions at that point? Was it really all about the Higgs or were there other things that were being discussed?

Shapiro:

Well, I think it was about electroweak symmetry breaking. I think at that point that was not necessarily the Higgs because many of us didn't think there was going to be a Higgs. We thought there would be a be some other mechanism by which the symmetry breaking took place. So the primary motivation was always electroweak symmetry breaking, and there was always a feeling that supersymmetry could be an important part of that puzzle of how this electroweak symmetry breaking was working. So in those days I didn't think of SUSY as something separate because, of course, SUSY has, in its simplest case, four or five Higgs, depending on whether you call the plus and the minus separate or not. So the idea of how you get mass to the particles is intrinsic to putting the SUSY in; it's not independent. But there, of course, were broad-based discussions of what other new physics you find, but I would say the combination of supersymmetry and searches for the source of electroweak symmetry breaking was really what was driving everything, both in the detector design and in our wanting to be there.

Zierler:

And so institutionally from the beginning, who were or what were some of Berkeley's key partners for ATLAS?

Shapiro:

So we played a very big role in—well, I shouldn't say very big 'cause there were a lot of big people. But we had important roles in the design and construction of the pixel detector, the design and construction of the silicon strip detector, and in software and computing. And those are the same three areas where we still were playing important roles. And our physics involvements very much at the beginning came out of the things we were building because when you build something you know how to use it, and so we looked for physics opportunities to use what we built.

Zierler:

What were some of the key technical challenges in the early years as things were getting started?

Shapiro:

The size, the number of channels, the needing low noise. The trade-off between cost and performance. So one of the big things that Berkeley pushed, for example, in the silicon strip detector is going to a binary readout where you only read a yes/no for each channel, which was a significant part of keeping the cost of the electronics down and keeping the material down because you could have simpler readout. And that's, in the end, what ATLAS went with. Radiation damage has always been a major challenge. And then, on the software side, understanding how to do reconstruction when you have many interactions per crossing, and understanding how you deal with such huge volumes of data and such a distributed computing network. Because it was a very different model. For CDF, the computing really all happened at Fermilab. And from the beginning, it was clear in the LHC era it was going to be cloud-based, distributed, heterogenous in the sense that the people who bought the hardware had some say in how it was configured so you could make some requirements, but you couldn't tell them, it has to look like this. So it led to very different software decisions.

Zierler:

Now, on the topic of distributed networking, is this pre-internet? Are you logging in and you can do things remotely?

Shapiro:

No. No. By the LHC era we were in a real internet stage. In my earlier lifetimes, that wasn't so true. But by the LHC era, the computing models—there was still the argument about Linux versus some kind of Microsoft operating system, but I think most of us at that point knew Linux was going to win.

Zierler:

Now, physically, how would you split your time between Berkeley and Geneva?

Shapiro:

I never spent the same type of time at Geneva that I did in Illinois when I was working on CDF, and not just when I was living there as a postdoc. I spent 10 years flying to Fermilab at least twice a month. I was a 100,000-mile-a-year flyer on United all between San Francisco airport and O'Hare, which is a lot of flights. [laugh]

Zierler:

Yeah. Yeah, it is.

Shapiro:

And that just never was possible at CERN, so for me that was difficult. I went for summers sometimes, but never actually moved out there for extended periods of a year. I always said I would do it on sabbatical, but it never really happened.

Zierler:

Yeah. Yeah. Now, to come back to this theme of cooperation and competition with CMS, how did that play out? What were some of the positive benefits of having that other player in the game, so to speak?

Shapiro:

Oh, I, I, I think that's always been positive in the sense that whenever I sit down to write a paper, the first thing in my mind is, “Can I convince my colleagues on the side of the ring that this is correct?”

Zierler:

Yeah.

Shapiro:

They're always the people who I'm thinking about when I write a paper, because if they believe it, then the rest of the community will believe it. If they don't believe it, then they're probably right.

Zierler:

[laugh]

Shapiro:

During the Higgs discovery, it, of course, was a very odd situation because everyone knew exactly what we were looking at and looking for. A decision had been made when the unblinding would happen and when there would be an announcement of whether or not the Higgs had been seen. There were time-periods of data taking, and when each period had been analyzed the two collaborations would say what they saw, and it was agreed in advance on what day that would happen. So we all knew what date we were working towards. And in principle, we didn't know what the other experiment had. And, of course, on experiments that size there's always some level of rumor, but it made you really think, OK, what am I willing to say? What do I believe? And, in fact, a couple of days before the announcement of the discovery of the Higgs at CERN—I was not there on the day of the announcement. It was Fourth of July weekend and I'd already planned to go back, but I was there when we had all the meetings to decide what was going to be shown at the announcement. I was sitting in the lounge at the airport, the Star Alliance lounge at the Geneva airport, and I could hear in the next row some people saying, “I don't know; I'm not sure it looks so good, but I hear it looks really good on ATLAS.” And I turned around and it was a bunch of people I knew from Fermilab who were on CMS. And the thing that was funny is I'd heard exactly the same thing the other way two days earlier at CERN: “Oh, no, this is a little dicey but I hear there's a beautiful signal from CMS.” [laugh] And I turned around and I said to the speaker, "I hope you know I'm sitting here."

Zierler:

[laugh]

Shapiro:

And he said, "Oh, everyone knows what's going on. It's fine."

Zierler:

Marjorie, as ATLAS was becoming a more mature operation, what was some of the key feedback that it was on the right track?

Shapiro:

For the Higgs or for—

Zierler:

For everything that ATLAS was designed to do.

Shapiro:

So I think there are some benchmark measurements where, when you start, you're not sure whether or not you're going be able to do them, but that really define the design decisions that go into your experiment. And when you see those benchmarks achieved, then that tells you the experiment is a success from the point of view of the design and the construction. And when you see whether or not you can actually use the data as effectively as you want to, that tells you whether the collaboration is functioning. And I would say both ATLAS and CMS had passed both of those tests. The fact that we were able to see Higgs to gamma gamma. You have this tiny pimple on top of this huge mountain of background, and we were able to demonstrate that we understood that pimple well enough and that we could describe the background well enough that we actually had a signal that we believed. I was amazed at the background that we saw. It was consistent with what we'd predicted. I was sure when we turned on, we were going to see a factor of 10 more background than we had predicted, and we didn't. So it was important because it was the discovery of the Higgs possible, but it also really validated our ability to do that physics. Another one I would put in that category is the W mass. I never thought you would see a W mass measurement from a Hadron Collider with the kind of uncertainties that we had, both the Tevatron uncertainties, and then again, the ATLAS uncertainties. In ATLAS, because you're doing this an environment will pile-up, I always say “We'll never beat the Tevatron on W mass. There's just no way that we can control the pile-up uncertainties well enough.” And so for me it was incredibly impressive that this measurement could happen. And, you know what? I think on the searches for beyond the standard model physics, if anything if we discover something new we will be able to really convince the world that our observations are correct. You can't put things into the data that aren't there, so I don’t know if we will find anything new, but I know that if we do it will be believed because we have demonstrated our ability to tell distinguish signal from background even in difficult circumstances.

Zierler:

Now, in the middle of all of this, you are named chair of the Department of Physics at Berkeley?

Shapiro:

Yep. Yep. I did three years as chair, and that was actually a much more enjoyable experience than I would've expected.

Zierler:

Did the department have a woman as chair before or were you the first?

Shapiro:

No. I was the first woman chair, and it was really interesting because the day after they announced my appointment as chair, I got all these emails and phone calls, not only from people in the department, but from the wives of faculty members in the department who were so incredibly supportive. And all of these faculty wives were calling me up and saying: “This is so wonderful that there's now a woman chair. Please tell us what we need to do to help you. We'd like to form a committee to make sure that we can help the graduate students.” And “Tell us whether or not you're having trouble with the faculty and we'll yell at them and tell them what they need to do.” I got more support out of the spouses, and it was all wives, because there weren't very many women on faculty in those days. It was not something I expected. And they were just so good to me. And they really did important things for the department, for example they'd make sure the first-year graduate students could get invited to dinner if they were lonely, and they would watch out for people. And they really cared about the department a lot. So that was a real surprise. Frances Hellman became chair after I did, so it's now an accepted thing in the department. But in those days, it was unusual. For me, I really enjoyed it. This was a chance to meet and get to know a lot of the people who I didn't know in the department. My main office was up at LBL. I knew all of the particle physics people, both theory and experimental, but I didn't have as much contact with some of the other groups, and so getting to know them, understand their needs, trying to understand strategic faculty hiring plans for me was very important. And making sure that the graduate students were being taken care of properly for me was a big issue that I cared about.

Zierler:

In what ways is the visibility of being a woman as chair useful in terms of the tenor of the department, of making it more inclusive and diverse? How seriously or how well did you think about those things?

Shapiro:

I think I've thought about them more since than I did when I was chair, but I think it does make a difference. I think there are changes that are happening in the physics community and the academic community in general, and as chair you can help make those changes happen more graciously and faster. And when I was a graduate student, the cult of the aggressive male physicist who told everyone else that they were stupid, and they were the only one who knew the right answer was really a cult. And that was considered what a physicist was like. And again, for me, Owen Chamberlain was remarkable because he was such an exception to that rule. He never acted that way. But it really was true that of a lot of the faculty very much viewed themselves as being the kings. The people underneath them were expected to do what they were told. And they enjoyed showing that they were quote "smarter" than the people underneath them. And that was viewed as being how you should interact. The aggressive male physicist would ask questions in the seminars to show that he knew more than the seminar speaker, and that was considered a good thing. So I think trying to have a culture that says the things your mother told you when you were five years old have a reason to be is important. [laugh]

Zierler:

[laugh]

Shapiro:

You should be considerate of other people. You should worry about them and make sure they're OK. I think that's a message that management has to send, any management, and department chair really is a manager. I got along very well with the staff, the departmental staff, and I think part of it is because I always respected their abilities, treated them with respect, and told them that I appreciated what they were doing. And it turns out that that was something that lots of the faculty never did.

Zierler:

Mm-hmm.

Shapiro:

And so even though it seemed normal to me, it made them really loyal to me.

Zierler:

Is a three-year term standard for department chair at Berkeley?

Shapiro:

Three to five. I stepped down after three because I didn't want to be chair when LHC was turning on.

Zierler:

Yeah.

Shapiro:

It was really driven by the LHC schedule—and it turns out there had been some delays in the LHC, but the time I stepped down was when we thought the LHC was going to begin its first run.

Zierler:

So to go back to something you alluded to earlier, at the time of the LHC turning on, what was the guidance that the theorists were giving at that point? What was to be expected and how well did that play out according to what the LHC saw?

Shapiro:

Well, we expected to turn on an see infinite supersymmetry. That's what we expected.

Zierler:

Yeah.

Shapiro:

We thought they were gonna have huge rates of supersymmetric production when we turned on, and, of course, we didn't.

Zierler:

And was that an immediate let down or that was sort of after a lot of data analysis?

Shapiro:

No. Because the first run had so little data that no one was so surprised. I think it was really the full Run one data set that convinced us that supersymmetry wasn't going to be this huge, easy-to-see thing. It doesn't mean it's not there, but it wasn't gonna be very low mass, very easy states to look at.

Zierler:

And is this exclusively because of the energies, or is it also about the quality or the type of the beam itself?

Shapiro:

It's basically the energy. You need enough energy to produce supersymmetric particles. If supersymmetry has something to do with electroweak symmetry breaking, the argument was that the masses of the relevant particles should be in the TeV-ish range, not in the 10 or 20 TeV range. And so if you're going to make something that has a mass of a TeV then you need to have a high enough energy accelerator to make it. And there was a big jump. The Tevatron was 2 TeV and we were supposed to be at 14 TeV, so that's a factor of 7 in energy. That's a huge jump. So there were good reasons to believe that there might have been copious production at the LHC.

Zierler:

When did the excitement about the Higgs really start to get tangible? How close was it to the announcement itself?

Shapiro:

Right from the beginning, the strategy for finding the Higgs was very well defined. That had been defined in a set of workshops many years before the LHC or the SSC were built. But one of the things about those early Higgs studies, they had to be done extremely well. I don't want to make it sound like it was just turning a crank. But the actual strategy was always known, and it was always known that you were going to need a certain amount of data in order to see the Higgs. I think a lot of us didn't believe it would happen as soon as it did. So I would say, in the six months before the Higgs discovery it was clear from the analysis of the earlier data that there was a potential for there to be a real signal there. You don't know until you go through the full process whether a small blip you've seen with low statistics is a fluctuation or real, but we knew in that six months that that potential was there. And so there was a very big buildup. And there aren't very many measurements in where collaboration the size of ATLAS everybody actually reads all of the documentation. The Higgs was one of those things. Everybody read the Higgs documentation. The experiment had huge meetings to try and explain to the people who hadn't been involved in the day-to-day analysis what was going on, to give them a chance to ask questions. And so it was a very intensive period.

Zierler:

And what was the culture of—ranging from gossip to even formal sharing of information—during this really exciting six-month period, what's the nature of communication between ATLAS and CMS, if any?

Shapiro:

In principle, you were not supposed to talk about the results to anyone who was not on the experiment. There, of course, were agreements between the spokespeople as to the dates things were going to be unblinded. We knew what had happened in the last set of openly shown things, but in principle you really are not supposed to talk to anyone who's not on the experiment.

Zierler:

And besides from the political reasons not to do this, just scientifically, is part of the reasoning there that you want true redundancy, that you want a double-blind test?

Shapiro:

Yes, you really do want for something like that, two independent measurements where neither side knows what the other person has. It's good to have blinded results. It's kind of hard to blind something like the Higgs completely because you need to have some control of backgrounds. So we tried as much as we could not to look at the signal regions, but I think having two totally independent analyses that, in the end, showed exactly the same features made it a much more convincing result than if we'd been communicating in between.

Zierler:

Now physicists, as you well know, can be pretty gossipy. Is your sense that people actually—

Shapiro:

Look, we have a number of couples where there's one on CMS and one on ATLAS.

Zierler:

Right, right.

Shapiro:

So I don't really know what their dinner tables were like—

Zierler:

How do you keep it separate? [laugh]

Shapiro:

—and I don't particularly wanna ask.

Zierler:

[laugh] Were you part of the discussions to actually make the result, the discovery public? Were you present for that?

Shapiro:

I was not a big player in the Higgs. I was in those meetings, but I was not a big player. I was much more getting ready to do SUSY.

Zierler:

Now, to go back once again to the standard model, when the Higgs was discovered, what was your sense for what that meant at that moment for the standard model? Did you view it as a capstone? Did you view it as a stepping stone to beyond the standard model? How did you view these things?

Shapiro:

So I think it's both of those. It's a real capstone in the sense that at this point, we know that the idea that masses are generated dynamically through the interactions with a field is correct, and that is a major, major intellectual statement. I don't think we know that the Higgs is the only thing. After all, there are plenty of models that have multiple Higgs, and many of them—one of them looks a lot like the standard model Higgs. So I still think there's the potential for there being other things there. So in that sense it is a steppingstone. It would've been, to be honest, pretty depressing if the Higgs had been 300 GeV rather than 125 GeV because it would've been much harder for that to be a steppingstone, and also there would've been a much less interesting Higgs program because it would have been dominated by a couple of decay modes and there wouldn't have been much you could study. So the nice thing is there actually is stuff that you can learn now, both by doing precision Higgs physics and doing other physics that's related, things like WW scattering where there's the potential to see deviations at large mass.

Zierler:

Now, you said that it was at this point that you start to focus more and more on SUSY?

Shapiro:

Well, when I first went to LHC, I always thought that what I was going to do at LHC was SUSY, but I thought I would be doing measurements, not searches. So my interest was always in trying to characterize what the correct SUSY model was, because SUSY is a generic terms for a class of models, it's not one model per se, and so I was doing a lot of work on trying to understand how you would know which of these variants of SUSY was correct once you saw initial signals. And a lot of the standard model physics that I was working on with my graduate students at the time was aimed at getting tools in place that I had eventually hoped would be used to do those characterizations of SUSY.

Zierler:

Now, how coupled or not was SUSY and its goals with the Higgs itself?

Shapiro:

Intellectually, very coupled; technically, not very coupled. ATLAS is big enough that it really has to stovepipe the analyses because you can't really have 3,000 people working on an analysis. It's just not a viable way to function. And so the SUSY group and the Higgs group really were independent analysis subgroups. And it also makes sense because when you're first looking for SUSY, then you're looking for broad features as opposed to doing a very incisive precise measurement of one thing. And so the importance of knowing things extremely accurately is different. If you're looking for a huge excess, then you don't need to know the backgrounds to a couple of percent. If you're looking for a tiny bump, then you do. So what you focus on in those two cases really is quite different, so it makes sense for the technical parts of those groups not to be the same. And it is true the different ATLAS physics groups do have very different working styles.

Zierler:

Mm-hmm. When, Marjorie, does LHC really start to get involved in cosmological questions, and particularly searching for dark matter?

Shapiro:

Dark matter has always been part of the program. In the early days, the thought was that the lighter supersymmetric particle might be the dark matter, so the SUSY searches were Dark Matter searches. There were always discussions about how you could put direct searches from underground experiments and ATLAS and CMS measurements on the same plot in a way that made sense. So dark matter has always been part of it. Then, when we did not find SUSY, discussions of other potential dark matter candidates that might be accessible began, and there's a long stage of looking at potential signatures, understanding how to pull those out of any background, and trying to make sure that everywhere we could look we have looked. And there's been a lot done on that, but that's still an ongoing area.

Zierler:

And just, Marjorie, to bring our conversation up to the present, what has been your involvement at CERN in recent years?

Shapiro:

So in recent years I have been working on standard model measurements, but measurements that are important for future Beyond the Standard Model parts of the program. So, for example, I had a graduate student who finished about a year ago who was looking at same sign WW production. That's one of these channels where you're looking for the scattering of two W bosons. If there are additional terms involved in the electroweak symmetry breaking, one of the first places you might see those is an excess of events in WW scattering. I've also been doing some measurements of W plus charm quark production using that as a test bed for something that might eventually be used to look for the Higgs charm coupling. The idea is that you develop your tools using well-defined signals that have important physics goals but not necessarily transformative ones, and then use those tools to try and push for the transformative goals. A lot of the work has been in recent years getting those tools ready. It's going to be a while before the increase in data is enough to really open the new vistas in that. It'll be Run Four of the LHC before some of these things come to fruition.

Zierler:

To clarify, when you say, "increase in data," that's just the creation of the data itself, not the data analysis?

Shapiro:

No. The creation. Because the high-luminosity LHC will increase the effective amount of data by an order of magnitude. So things that we could not see in the present it is possible to see when you have that much more data. We've only collected about 5% of the data we will collect with the LHC.

Zierler:

So what you're saying, of course, is that there's a tremendous amount of work that still needs to be done, even within the standard model?

Shapiro:

Yep, that's right. That's right. And the level of precision we need to get to is much higher than what we've had in the past, which means you need new techniques, you need to have better understanding of the theory. So if you need to know the theory, well, that means you need to test whether your calculations are good enough, and you do that by measuring standard candles. And for me that works well because I really enjoy working with graduate students and beginning postdocs. And these standard candle measurements are incredibly good training for them, as well as being really important parts of the overall campaign.

Zierler:

That's right. Marjorie, that's a great place to pick up for the last part of our talk, which is, I'd like to ask you to survey what we know in experimental particle physics from your direct career, what are the things that are within reach right now? And looking to the future, as you say, these steppingstones, we have to get all of these things in place now because if we do that only then will we be able to make the really transformative discoveries later on.

Shapiro:

Mm-hmm.

Zierler:

So retrospectively, from the time when you were a graduate student when you started to become able to ask these questions in a sophisticated way, what stands out for you academically, intellectually, in your memory as things where, when you started, the field did not understand these issues in physics really well but now we do? What are some of those things that stand out in your memory?

Shapiro:

So I would say the starting point for me again was the discovery of charm, which I think really finalized the belief that quarks were real. Now, we knew from the late '60s from deep inelastic scattering that there were quarks, but the fact that you could make a model that looked like the hydrogen atom, which is really what quarkonium is, I think was the first time we really intellectualized, these are really what we're gonna be working with in the future, so that's the basic building block of matter of the quarks. On the electroweak side, really understanding parity violation, how intrinsic it is to the standard model. On the QCD side, knowing that when you get to high enough momentum transfers you can use perturbation theory and can actually do precise calculations because, in the old days, we thought, well you can never do a precise calculation; the strong coupling constant is just too big. And then, the whole LEP and Tevatron era where, especially at LEP, they demonstrated that loop corrections worked. The idea of a gauge theory with renormalization could give you precise measurements outside of QED, and we all knew about Lamb shift and g-2, but the fact that this worked for the standard model as a whole was really fantastic. And I think at this point the standard model is definitely a whole that's there. It's not gonna go away. It doesn't mean that's the only thing, in the same sense that classical physics hasn't gone away even though we now know about quantum mechanics and relativity. But I think it's clear that at the energies we're talking about the standard model does what we need. And then, the real question is how do we put dark matter in there? Will we ever be able to do anything to put gravity in? And can we ever find anything that will allow us to do a grand unification of the forces? And, again, proton decay has always been the way we've talked about grand unification. Whether that continues to be the best way forward, maybe someone will have a new idea. And the last really new idea in a lot of this was the idea of extra dimensions and the fact that maybe you could access quantum gravity because the scale for gravity might be small. And again, we don't yet have any indication that's correct, but there are paradigm shifters that can happen.

Zierler:

And so, for right now, if we are in building block mode for those next transformative questions, what are some of the open question marks right now that seem to you to be within grasp?

Shapiro:

So I think there's still a huge open question mark on CP violation. We don't have enough CP violation to explain why we have a matter-dominated universe. The conditions for that were laid out long ago, but we don't have a mechanism to give it. So that really does need to be understood. Again, there was some hope SUSY might provide extra avenues for that. We just need to keep looking, so really understanding where the extra CP violation is, understanding what the source of dark matter is, and seeing if there's any way to address the question of how to incorporate gravity and any way to address the question of whether or not you can unify the interactions. Those, I think, are still the big pictures. I mean, it's not so different from 1988. [laugh]

Zierler:

Yeah. Yeah.

Shapiro:

It's the same big questions. Except now we do know that electroweak symmetry breaking is there, and it's there in a way that looks pretty much like what the standard model said it should be.

Zierler:

Well, on that point, Marjorie, for my last question, looking forward, because you are a mentor to graduate students and because you like working with postdocs, right?

Shapiro:

Mm-hmm.

Zierler:

For them, they have their whole career in front of them.

Shapiro:

Yep.

Zierler:

So what would you advise, or what do you advise is the most efficacious way of pursuing these questions?

Shapiro:

I tell them that they need to have the broadest possible background they can get. That graduate school is the time when they can do everything, try everything. That there's no way of knowing what's going to be the most important thing 20 years from now, but they want to be ready for whatever happens and feel that they have the training that they can do whatever they need to do. And so I really discourage them from narrowing too much. Some of them will say, “Well, I really don't like building stuff. Can't I just do software?” And I say, “Well, you could, but I don't think it's a good idea.” You want to know how to build things. You may never build anything again, but you want to always know that if it's important you can. You want to do something that's used by other people, and you want to have an analysis that you really feel that you had a major part in and that you own, and you don't want to just keep repeating what you did as a graduate student.

Zierler:

And of course, that accords with your own career trajectory?

Shapiro:

Yeah, it's true. [laugh] But I think there are lots of different paths I could've taken, and it was important that I always felt that I had options. I think the worst thing is to not have options, and that's really the most important thing for students.

Zierler:

That's it. Marjorie, thank you so much. It's been a great pleasure spending time with you. I really appreciate it.

Shapiro:

Nice talking to you.