Some people stay at Caltech for years, others only briefly touch down as students or visitors. And then there are the Caltech lifers: those who come and stay . . . and stay, and stay . . . and whose presence leaves a lasting imprint on the Institute. Carver Mead is among those Caltech lifers: BS '56; MS '57; PhD '60, and still going strong as the Gordon and Betty Moore Professor of Engineering and Applied Science, Emeritus.
A recipient of the 2002 National Medal of Technology, Mead is celebrating his 80th birthday on May 1, 2014. He remains as passionate today about science and engineering as he ever was. "There isn't really a time when you're too old to have new ideas," Mead says.
Mead is best known for his pioneering work on VLSI (very-large-scale integration) circuit technology in the 1970s and 1980s, which made it possible to greatly increase the number of transistors placed on a single semiconductor chip. It is no exaggeration to say that the computer era we live in would not have been possible without VLSI technology. Thank Carver Mead when you turn on your computer today, or flick the screen on your smart phone! But don't expect him to be there waiting for applause, because Mead long ago moved on to something new.
Different decades have found Mead wrestling with different problems, from solid-state physics to VLSI to electronic circuits and systems that attempt to mimic the architecture of the human nervous system—so-called neuromorphic engineering, a concept Mead developed. "Retirement" finds Mead living in Seattle and working on the fourth phase of his storied scientific career: issues in fundamental physics, such as those that inspired his "little green book"—Collective Electrodynamics: Quantum Foundations of Electromagnetism—which derives the results for standard electromagnetic problems directly from the quantum nature of matter rather than in the traditional manner, via Maxwell's equations.
Mead recently reflected on his life at Caltech.
How did your relationship with Caltech begin?
It's an interesting story, actually. I was from the backwoods. I went to high school in the little town of Fresno, California. My parents wanted me to go to Fresno State because it was cheap, but I couldn't find anything there that I liked, so I applied to Stanford and Caltech. We went to visit each school after I was admitted. At Stanford we asked if there were any tours, and they said no, and gave us a map. We walked around a little, and it was very nice, but we didn't get to see any labs or anything.
Our experience at Caltech was very different. We showed up at the admissions office—it was in Throop Hall at the time—and met a very nice lady there . . . one of the Caltech ladies who know how to do everything. She called the Caltech branch of the YMCA [now the Caltech Y] and they sent over a young man to give us a tour of the campus. We got our own private tour, my parents and I. As we walked by the astronomy building, I asked our tour guide if we could get a look at the 20-inch telescope. This was the 1/10th scale model for the 200-inch telescope on Palomar Mountain. It was up on top of the Robinson building [now Linde + Robinson].
Our tour guide went into Robinson and he asked the lady at the front desk, "Is there any chance I could let these people see the 20-inch telescope?" She said, "Oh sure, here are the keys." We went up, and of course this telescope was the most fantastic thing in the world. I was going around explaining what everything was, because I had studied up on it.
When we went to return the keys, I got my courage up and asked if there was any chance that we could go down to Palomar and see the real thing. And this very nice lady told me, "Well, they don't give tours there. But if you were to go down toward the end of the day, but when it's still light, and bang on the door of the dome, there might be somebody in there getting ready for observing that night. If they're not too busy they might just let you look at the telescope."
My parents were intrigued too, so we thanked our guide and got in our car and drove down to Palomar. I very bravely walked up to the dome and banged at the door, but no one answered. We waited an hour and knocked again, and just as we were about to leave, a big tall guy with blue eyes opened the door and looked at me. I told him I had just been admitted as a freshman at Caltech and wanted to see the telescope. You could tell he was trying to decide whether to be annoyed or compassionate. Finally he looked at me and said, "Sure, come in." That was Alan Sandage. He was Edwin Hubble's graduate student and became famous for doing the Hubble survey plots for many, many years. Once I got to Caltech, first as a student and then as a faculty member, I attended all his seminars. Unfortunately, we don't have Alan with us anymore, but he was a wonderful man, and the real reason I got to Caltech.
If Sandage is what got you to Caltech, what made you stay?
The most important thing to me about Caltech is that if you're working very hard to understand something, when somebody asks you why you're doing it, you can say, "I really want to get to the bottom of this," and that's enough reason to be doing it. I don't know that there's any other place in the world where that's sufficient reason to take on something new.
When you started at Caltech did you know that you wanted to do engineering?
I knew I wanted to do technical things and I was very interested in electronics. Even then it was clear to me that there was a lot of technology in astronomy. That is even more true today than any of us imagined back then. But I ended up doing electronics and related things and maintaining an interest in astronomy.
Was teaching an acquired taste, or did you like it from the beginning?
Oh, I loved it from the beginning! I started as a teaching assistant when I was an undergraduate: I made up an exercise on electromechanical transducers for a lab course. I taught all the way through graduate school, and I have always made sure that my grad students teach at least one year. I push them pretty hard to teach more than that, because I've learned so much from teaching. It's just so neat when you see people light up when they finally get it. That's the fun part for me.
But I could only teach the stuff I was interested in. If I wasn't interested, I just couldn't teach it anymore. So it was great being at a place like Caltech where I could teach the stuff that I was good at. When you're excited about something and you get all charged about it, then the students pick up on that.
Have there been any major changes in the Caltech culture from the time you arrived as an 18-year-old in 1952 until now?
I think the basic Caltech ethic is still there. I think the biggest single thing that has made life at Caltech more reasonable was the admission of women. I was always a big proponent of having students of both genders. I was the advisor for the first female EE [electrical engineering] student, Louise Kirkbride. She's now on Caltech's Board of Trustees. And I've always had women in my research group. It makes a big difference, just in the whole tenor of things. It's wonderful that we've been able to find so many outstanding women and that they've been doing so well here.
You've explored several fields in depth. Do you have a favorite? Is there any work that you would describe as your greatest source of pride?
Oh, I don't know. They were all great fun at the time. You know though, when you're working on something, you are stuck most of the time because you're trying to figure it out. I've spent my entire career being stuck. People don't find that very interesting, and they don't give you the time of day about it. But then 20 years later when it starts to look like a good idea, they start calling you. By that time, I'm working on something else.
For example, I've gotten three or four calls in the last month asking me to give big talks at big conferences on neuromorphic circuits. But I haven't done it for 15 years, or maybe 20! I tell them to talk to my students, because they are current in the field and doing leading-edge work right now. My students are really what I'm most proud of.
If you could go back in time, what would you tell your 18-year-old self when he first stepped onto the Caltech campus and asked to see the 20-inch scale-model telescope?
I'd tell him that when you're in groups of people, whether they're groups of undergraduates or people at conferences, there will always be somebody who makes sure you know that they know a lot more than you do. I always felt very inferior to those people.
Gradually I learned that those aren't the people who really know interesting things. The people who really know things are people like Kip Thorne. You have a hard time getting it out of him sometimes, but there's a lot of knowledge stored in his head. Gordon Moore is like that; John Bardeen was too. The people I've gotten to know who are really on top of what they're doing aren't the ones who are out bragging and beating their chests. They're the ones who are thoughtful and just doing their work.
It took me too long to learn this. Even as a faculty member, you find this attitude everywhere, especially if you're doing things a little differently from other people. So I would advise people, don't let the know-it-alls put you down. Just follow what you believe is right, and you'll get there.