Jeremiah P. Ostriker - Session II

Smeenk:

Ostriker in his office in Cambridge, and the date is May 21st. I’d like to start by asking you about your various administrative positions, your role in overseeing scientific research, both on the decadal surveys, as the chairman of the department at Princeton, and the director here. I’d just like to ask you to comment generally on that other aspect of your career.

Ostriker:

Sure. Let’s see. Let me take the pieces. National Academy of Sciences: I was on their council and government board; and I think I was on the decadal survey with Greenstein. So that’s three [unintelligible word]. That’s in the 70s. And then — so I was on three: Greenstein, Field and Bahcall. And I organized for the Academy three [surveys]. Not with Greenstein, because I was young. Field, Bahcall and the latest one — McKee and Taylor. Sometimes, that was a bit traumatic because we had a policy of really trying to get the astronomers to agree on an agenda for the next decade. And I, very forcefully, argued that we should come out with a prioritized list — the things we wanted to do. All the disciplines hadn’t done that. And the arguers sometimes said, “Well, how can we prioritize different fields in unrelated ways, and who could be so expert as to do this? To say whether this ground based is better than this space based, or that this infrared is better than this optical [two unintelligible words]? How can we say that?” And so most disciplines just end up with a study where they bless everything.

Smeenk:

Right.

Ostriker:

The argument which we, and I in particular, used was, “Well, not all the things that we want to do are going to be done. So decisions are going to be made. Someone is going to prioritize them.

Smeenk:

And it might as well be you.

Ostriker:

It might as well be our Community, however, we can do it because however difficult it is, we have more information, more understanding of these [issues]. And that was ultimately persuasive, but it’s a hard fight because when you are sitting in a room full of people, they know that they’re all not going to be number one. [Laughs] Then, they begin to think that [this] method isn’t a good method.

Smeenk:

Do you remember any particularly traumatic conflicts that resulted?

Ostriker:

Well, I remember — in the first one which I didn’t organize because I was a junior member, I was on the executive committee — when Jesse Greenstein got so upset about the inability to come to a consensus that he marched out and wanted to close the whole thing down. We managed to bring him back and put it back together again. John ran it fairly forcefully, John Bahcall. George Field was more laissez faire. But at the end, in each case, we did come out with a list. The last such list was — sometimes, there was a problem that someone’s project wasn’t on the list at the end, among ten very good projects. And then, they were being [unintelligible word], “Well, this project wasn’t considered by them [the committee].” But the truth is that it was considered, and [it was] just below ten. We didn’t see any point in saying that the projects were just not considered worthy. We just listed the ones which were considered worthy, and —

Smeenk:

Right.

Ostriker:

But that happened with LIGO, which I mentioned to you.

Smeenk:

So that wasn’t one of the top ten —?

Ostriker:

It wasn’t. Bahcall and the committee did consider it, and didn’t rate it among the top ten.

Smeenk:

So there’s no list of the “also-ran” projects?

Ostriker:

No. I wasn’t unusual among that group of astronomers in thinking that this was not — Remember, I talked to you about that earlier?

Smeenk:

Right.

Ostriker:

That was the consensus view, that it was not [unintelligible word; “compatible” perhaps].

Smeenk:

Right. Do you see any shift away — So, the three decadal surveys that you were involved with, I think —

Ostriker:

I was involved with four. The three I organized, and they overlapped.

Smeenk:

Right. Each of those had a very large project that was the main — I mean, that’s what people now associate with —

Ostriker:

No, I don’t really think so. Because the [unintelligible word; ST perhaps?], for example, in [unintelligible phrase], turned out to have been between decade ones. Never got on either list. You have to try to evaluate [it] in more than one kind of list, because small, medium and large — You are not going to rate a very small project, which might have ten scientists involved in it, compared to one which would have a thousand. So, we did come around to rating them in groups: the biggest ones, the medium ones and the small ones. And then, on the big ones, you know all the ones that are there. On the small ones, you can only give representative clues to what kinds of things they’ve got. But I think that the process was a good process because it was also community consensus building; that in thinking what we really wanted, we got to know one another and ourselves. And so it meant that the optical astronomers did talk to the radio astronomers, etcetera. So I think that it was a very good process. And I know, from my work on the council and the governing board, that the astronomers got a lot of praise for being willing to do all this internal work, compared to other disciplines. I am happy with that part of my career, that I took part in that. And an equally important part, and one I didn’t take part in but one where John was very effective, is selling [two unintelligible words] to the congress and the executive branch. So, I was important behind the scenes, but not at all important in front of the scenes, which is equally or more important in the end; because it doesn’t matter how good a report you write if you don’t get out there and sell it to the people who wanted it and who commissioned it. And some people are better at it than others. So that’s a few words on that whole topic. As chairman of the astronomy department — and that was relatively easy because it had always been extremely well run, by Henry Norris Russell and by Lyman Spitzer. And so I more or less followed their model of how to do things, which you could say was benign despotism. Some academic departments, I realize, have one academic meeting a week — it goes up to that. We had two a year — one to let the students in and one to let the students out. And Lyman’s method was: if somebody cared intensely about some aspect of things, then he would ask that person’s advice and do what they suggested; because otherwise, you have continual battles and then you break the department in two. And if somebody says, “I think we should have green toilet paper in the bathroom,” and someone else says, “That’s absurd. It’s wasting money. We should have plain white toilet paper.” And then you could spend weeks debating this, and it wouldn’t make the slightest difference. [Laughs] And, in addition, everyone would complain about how much time they have to waste in meetings.

Smeenk:

[Laughs] Right.

Ostriker:

So we had a different system. And I think that it’s continued, more or less, that way, because everyone gets along very well. And basically, the chair just tries to see who cares about what. They just tend to do that. You can’t do that in a huge department, but at a small one it’s always doable. And I guess the thing I am proudest about is the recruitments, the people that I was able to get to come, and then give them the tools to do their work. Jim Gunn, Bohdan Paczynski would be notable examples of my generation, the ones I recruited.

Smeenk:

And what led you to move into the position of provost? This was in 1995, I believe.

Ostriker:

Yeah. Well, you know, I had had some contact with the president on and off, and I was on various committees. And he asked me. It was sort of an elliptical and a bit of a dance. I didn’t know whether he wanted me to be in the faculty, or provost or — We had these meetings, and finally he asked me if I wanted to be provost, when the previous provost died. It worked very, very well in the sense that Princeton is small enough, and the cooperative relation between the president and the provost was sufficiently good that — I remember him saying earlier, “There is no need for both of us to be at any meeting.”

Smeenk:

Yeah. That’s a very, very good relationship.

Ostriker:

Yeah. I never identified myself as being an administrator, which was a little bit awkward in my dealings with other administrators.

Smeenk:

And you were still — I mean, you continued publishing throughout this time?

Ostriker:

Oh, yeah.

Smeenk:

So you were still very active in your research.

Ostriker:

Yeah. I wrote as many papers as before. Who knows if they were any good or any bad, but there were many. I just made some ground rules when I took the job: no breakfast meals, no lunch meals, no dinner meetings, except if called by my superiors, which was only the board of trustees and the president. So I didn’t do any of the administrative socializing that they all do. I think they thought I belonged to the enemy camp to some extent, some of them, because there is a purely social aspect of these jobs. You know, I had almost no regular meetings with people, I would say. “Well, come to see me whenever. My door is always open.” In many administrative fields, there is a tremendous amount of [unintelligible word; “make” ?] work, where people just sit around the table; because if they are not there, they will feel as if they have been left out and are not considered important. So if you just focus actually on doing things that need to be done — And you need other people to judge how good a job I did. But I was happy with the things that were achieved.

Smeenk:

Were there any particular things that, when you took the job, you set out as a goal?

Ostriker:

Yeah.

Smeenk:

What were those?

Ostriker:

The things I talked to Harold [Shapiro] about would seem rather obvious. One is improving the educational process, because in high-level Ivy League universities, there is a tendency to turn into research think tanks, where they aren’t actually paying attention to undergraduate education. There were programs, for example, which gave funds to faculty members who did innovative curricular things, which I set up. There is a whole variety of different tools — I preferred to work with a carrot rather than a stick because the latter never works. To encourage people, to reward them, to be really conscious of them paying attention to their teaching. So that was one goal. Another was a better record of employment of women and minorities, mainly blacks. Princeton had a poor record in some areas, and a terrible record in other areas. It was actually not bad in some [areas] for blacks, for senior-level blacks. For women in the sciences, it was ghastly.

Smeenk:

Just looking over your CV, I noticed that you had a paper that, I believe, you coauthored with your wife, about gender issues in academia.

Ostriker:

Yeah. It always interested me. My grandmothers on both sides were suffragists. And that’s always been —You know, my wife is a professor, my two daughters are professional women. I’ve always felt pretty strongly about that. And the record at Princeton was really, really, really bad in some areas. Maybe it was the year I became provost, or maybe it was the year before, but I checked: in the three biggest physical sciences and areas — Chemistry, Mathematics and Physics — guess what the total number of tenured women was?

Smeenk:

Umm… I have — Ten.

Ostriker:

[Shakes his head no]

Smeenk:

Zero?

Ostriker:

[Nods]

Smeenk:

[Laughs] Wow!

Ostriker:

So, at that level, you have to say that there is a lot of room for improvement.

Smeenk:

Yeah, that’s true. That’s true.

Ostriker:

[Laughs]

Smeenk:

So did you have any —?

Ostriker:

So that was the second thing that I worked on, and I think I got a lot done. We certainly moved up in all the numbers.

Smeenk:

Do you have any broader assessments of why that is?

Ostriker:

This would take us more time.

Smeenk:

Okay.

Ostriker:

Then, well, Princeton was also late to go co-educational. Let me put it this way, make it most complimentary. This is a very traditional school and changed very slowly.

Smeenk:

What were your other goals that you remember?

Ostriker:

So that was the second one. A third one was financial aid: to do more for both undergraduate and graduate financial aid. We could afford to do a lot more than we were doing. The opposition was mainly in the administration, both the trustees — the faculty, the students all wanted it. But, George Bernard Shaw says: “Every profession is a conspiracy against the laity.” [Laughs] That was certainly the case.

Smeenk:

Right. So was this partially — I’m just thinking that —?

Ostriker:

We ended up — of course, I worked with Harold and other on this — we ended up setting up a panel for a whole Ivy League, which then set a pattern for the country. To take one very simply expressed goal: anyone at Princeton who applies and is accepted — and the acceptance always [inaudible phrase], [the acceptance] has been separate from financial aid.

Smeenk:

Right.

Ostriker:

But whose family has below-the-median income of the country, comes in free.

Smeenk:

Oh, wow! I applied to Yale in ’91, and I knew at that time that Harvard, Yale and Princeton all had need-blind admissions and they gave financial aid based on need. But I think that at that point, there were still meetings of the financial aid offices to ensure that the financial aid packages were all similar.

Ostriker:

And when we changed, it was breaking ranks and everyone was very, very unhappy.

Smeenk:

Oh, I can imagine, because that would have been a much more generous package.

Ostriker:

We ultimately offered a much, much more generous package than anyone else. Of course, they all had to compete. And then, they basically did in the end. But it affected not just Harvard and Yale but many, many other schools — that we did this. And the truth is that people could afford to do it. So, for the undergraduates — and now there are no loans even, because of that category —

Smeenk:

If only I had been a few years younger. [Laughs]

Ostriker:

And also for graduate financial aid, we did a lot. There, I think we set a model for many other institutions. So those were all the things I really wanted to do. Those were general areas, but happened to be influential. The other areas which were peculiar to Princeton — and I knew the problems were so large that I worked with a lot of other people, and still made only marginal progress — for example, the social system of Princeton, which is the clubs and whatnot — Woodrow Wilson, Breaker’s Neck — although that, I was not going to go to the mat on. But we did manage to make some changes which should make living in colleges more attractive, and perhaps make the clubs — I don’t want to kill the clubs — but make them more like they are at Harvard, where it’s just something that a small number of people get off on, and great for them. But I didn’t even know they were there until my senior year. Whereas at Princeton, they actually dominate the social life. So, I worked a little bit on some of those social [inaudible word]. But I always saw all these administrative things as something that you should be able to do with one hand. And there’s always the question of identity — you know, who are you? And I remember that when I would do some of these things as provost, people would say, “Well, now you’re joining the other side.” And it took a while for people to realize that this was just a job I was doing for a while; that I was continuing as a scientist and doing all the same things: continued to have graduate students and write papers and go to conferences and everything like that.

Smeenk:

Were the time commitments a lot more than what you had been devoting to teaching prior to that?

Ostriker:

I have a funny attitude towards that. I think, “There are only so many hours in the day. Use them all up. And there’s always time to do things that you want to do. And there’s no time to do things you don’t want to do.” So, I never saw time as being a big constraint on this. When people who take administrative jobs say, “I didn’t have time to continue my research,” I think to myself, “Did you have time to have dinner yesterday?” Yes, you did! You wanted to have dinner! “Did you watch any television?” I don’t ask them these questions [laughs]. I don’t want to give myself a lot of credit for this. I just think that people do what they want to do, and this is what I wanted to do. So I found the time. And in both areas, things that weren’t an effective use of my time, I just didn’t do. Even though people commonly did them.

Smeenk:

What prompted your move to be director here, and —

Ostriker:

I’m not really director here. I wanted to clarify that.

Smeenk:

Oh, okay.

Ostriker:

The Plumian Professor used to be director here. Doug Gough was the director. I have this honorary and ancient professorship. But I’ve taken very little part in running the place as director because I really didn’t want to. I don’t think they were eager for me to. But in any case, I absolutely didn’t want to. I’d had enough directing of things. I just really wanted to be a scientist.

Smeenk:

You still have ties with Princeton, is that right?

Ostriker:

Yes. So I’ll be back [at Princeton] Thursday. I have postdocs and graduate students that I’m still working with. This is for three years because of compulsory retirement. And then, I’ll be going back to Princeton.

Smeenk:

So when you accepted the position, it was clear to you at that time that —

Ostriker:

Clear to that. We made an agreement.

Smeenk:

I mean, does it say that there’s compulsory retirement [unintelligible phrase]?

Ostriker:

Right. It’s the law. So it was perfectly clear.

Smeenk:

That’s interesting. And when you go back to Princeton, will you be resuming your duties as provost?

Ostriker:

No, no, no. I’ll just be a professor in the astronomy department. Whatever else I do, I’ll see.

Smeenk:

Do you want to go back to talking about research?

Ostriker:

Sure. Sure. I guess the summary on that is that my mother was a [unintelligible word; “worthy” perhaps?] intellectual, my father was a practical man of action, business. And I had some inclination towards both. More on the intellectual side, scientific, but a still non-negligible interest in seeing if I could make a difference in the world, if I could get things done. So I combined those as a minor theme in my career as an astronomer. And I’m still doing some of those things. I am, right now, chairing a commission for the National Academy of the Sciences on evaluating all graduate programs. And a NSF cyber infrastructure one on evaluating computing needs for the next generation. So I’m continuing on some of those. Okay, back to science. “Galactic Disks, Infall and the Global Value of Omega.” I had a very simple idea on this. A merger hypothesis for galaxies is one that is natural and, in fact, is inevitable. In other words, if galaxies don’t come out of black holes, then they come from collecting parts. So there’s no alternative to some mechanism where galaxies are made by putting pieces together. But there is a period when [loud interruption from lawnmower outside] —

Smeenk:

Maybe we should let him finish.

Ostriker:

He’s mowed the same piece of land ten times!

Smeenk:

[Laughs]

Ostriker:

[Laughs] It’s only about two meters of lawn. There was a period when that was the explanation for everything. It didn’t make any sense because the number of mergers at late times is very low. I think we now understand that in a low omega universe, it stops late. One of the arguments that I used — and this is what the paper presented — was that if you have lots of things falling into disks, it’ll thicken them up. And the fact that galaxy disks are so thin provides a technical dynamical argument that since those disks formed there wasn’t much merger activity.

Smeenk:

Interesting.

Ostriker:

And that turns out to be a very strong mathematical argument for the lack of late mergers.

Smeenk:

So if there were a lot of mergers, they had to be before the disks formed.

Ostriker:

Exactly.

Smeenk:

Anything after that, you have a strong constraint, right?

Ostriker:

It’s a few percent. Which doesn’t say it didn’t happen; but it’s not happening now, at any rate. I think we now understand that in a low omega universe, all the mergers occur at high redshift, and there’s not much of that now. But this was the first paper which made that point. And then, there are really a whole lot of papers – starting in the early ‘90s, the last decade — on hydrodynamics of galaxy formation and large scale structure. Much of this was with [unintelligible word] Cen, some of the [unintelligible phrase]. I don’t know how I would summarize it. I would say, briefly, that we were one of the people who led the way in really trying to put in all the equations and all the physics and doing it. That’s the most positive thing I could say, and I think that now people realize that this is the way you have to go, that this is the path of the future. Also, if I stand where my critics are and say that we did it when the technology was not up to it, and that we also didn’t have as much spatial and temporal resolution to really address the questions that we were trying to address. So —

Smeenk:

And those are being addressed now, or are those —

Ostriker:

Well, it’s just that it’s getting better. You never have enough. But it’s Moore’s Law that computers keep on getting better. So everyone is using techniques that are similar. Some use SPH, which we didn’t use. Some use —

Smeenk:

Sorry. What’s SPH?

Ostriker:

Smooth Particle Hydrodynamics. So two of my students did moving mesh: Nick Gnedin and — And we used the Eulerian mesh, which is a fixed mesh. And there are pros and cons of all the different technologies. But everyone is using similar methods of solving hydrodynamic equations: putting some radiative processes in, and cooling, heating, etcetera. I think it’s becoming standard. So, I think that the most positive thing I’d say is that we showed that this was the way to go, and my students and I are among the major contributors. I think the most critical thing you could say is that very often, we didn’t have enough resolution to do what we were trying to do, and the result suffered from that. Now, if I were to pick results which came out, which were new and, I think, are generally recognized now as correct, we and others got the correct explanation for the Lyman-alpha clouds, which are these fluctuating density fields which you look [at] through the [unintelligible phrase]. We weren’t the only ones; there were many others, at the same time using associated techniques. So that, I think, is a success story.

Smeenk:

Can I ask you a more general question just before you continue? In one of your review articles on this, you emphasize that there is an important shift in the goals of these hydrodynamical simulations, where, basically, because you don’t know how to model star formation, you shift to other objects like the Lyman-alpha clouds, X-ray clusters and so on.

Ostriker:

Exactly.

Smeenk:

When did you start shifting attention to those other —?

Ostriker:

See, that is part of the reason why — I’m trying not to get defensive — my work didn’t get treated the way it should [have been]. Because everyone is interested in galaxies. That’s what the extra-galactic world is, to most astronomers, especially optical astronomers. And one, I never addressed this very much, only partially. I could say where they were formed [unintelligible phrase], and when they were formed, but not much about their internal structure. And therefore, I wasn’t talking about the things that most of the people were really interested in. I thought that it was just too hard a problem. People who have tried to do that with the semi-analytic model of things got questions where they could address the things that the observers were interested in. But I didn’t think much of the methods. I thought that they would just have enough free parameters until they came out with something that looked like the real sky. It certainly agreed with observations, but it couldn’t fail, even when they changed the input theory from omega = 1 to omega = 0.2. It always fit, because it always had to fit. But since I didn’t work in that area very much, a lot of people weren’t — and I never really did — a lot of people weren’t that interested in what we were doing. On the other hand, I was interested in the intergalactic medium. I thought things could be done there, with X-ray clusters, Lyman-alpha clouds. And we had some successes, I think, some failures. And there were many who succeeded. I think Greg Bryan succeeded with [unintelligible word] alpha clusters very well; Lars Hernquist and others on the Lyman-alpha clouds. But I think that the work that was done in those areas was very successful. A primary thing, on which the jury is not in yet, is a paper that Renyue and I wrote, which is now, just up to almost the present time — “Where are the Baryons?” — where we proposed that most of the ordinary matter in the universe, at late times, is in, more or less, million degree gas, which is very hard to detect. So it was a proposal. And then subsequently, several groups have tried to look at it in either line emissions or line absorption — to see it from [unintelligible phrase]. Preliminary indications are that we were right, that this is where most of the baryons are. So that was a genuine —

Smeenk:

Sorry. This is — gaseous disperse in the intergalactic medium?

Ostriker:

Exactly. So that I think is one —