[Curator’s note: The following material quotes and paraphrases extensively from articles posted by the Nobel Prize Committee and The Princeton Alumni Weekly.]
Nobel Prize in Physics
The Nobel Prize in Physics 2017 was divided, one half awarded to Rainer Weiss, the other half jointly to Barry C. Barish and Kip S. Thorne "for decisive contributions to the LIGO detector and the observation of gravitational waves."
One consequence of Einstein’s general theory of relativity is the existence of gravitational waves. These are like ripples in a four-dimensional spacetime that occur when objects with mass accelerate. The effects are very small. Beginning in the 1970s the LIGO detector was developed. In this detector laser technology is used to measure small changes in length caused by gravitational waves. Kip Thorne has made crucial contributions to the development of the detector. In 2015 gravitational waves were detected for the first time.
I was born on June 1, 1940 in Logan, Utah, USA, a college town of 16,000, nestled in a verdant valley in the Rocky Mountains.
My father, David Wynne Thorne, was a professor of soil chemistry at the Utah Agricultural College (since renamed Utah State University). Over his lifetime he had a major impact, through research and consulting, on arid-land agriculture, not only in the USA but also in the Middle East, Pakistan, and India. He was an intellectual inspiration to me.
My mother, Alison Comish Thorne, with a PhD in economics, aspired to be an academic, too. However, her career was thwarted by Utah’s nepotism law that forbad the wife of a University employee from also working for the University; so she devoted most of her life to community organizing and community activism, and to raising and mentoring five children. Her lifetime impact on the community led the University to award her an honorary doctorate in 2000, when she was 86; and in 2004 when she died, a giant headline in the local newspaper, the Herald Journal, read “Old Radical Dies”.
As a young boy, I discovered, in a bookstore in Salt Lake City, a paperback edition of One, Two, Three, …, Infinity by the physicist George Gamow. It dazzled me. It revealed the role of astronomy as a subfield of physics, the role of mathematics as the language of physics, the beauty of Einstein’s relativity, and the power of physical laws to explain the universe. I read it three times and decided I wanted to become a physicist, pursuing a quest to understand the universe. Fourteen years later, when I had started publishing my own research, George Gamow sent me a letter inquiring about ideas in one of my publications. Thrilled, I wrote back, telling him I was a physicist because of having read his book three times. In response, he sent me a copy of One, Two, Three, … Infinity in Turkish, with an inscription “To Kip so that he would not be able to re-read it a 4th time”. That book remains one of my most treasured possessions.
University student years
When I arrived at Caltech as a freshman in September 1958, I found myself overwhelmed. I had had no calculus, I was a slow reader, and it quickly became evident that my thinking was slower than that of most other Caltech freshmen. I stumbled and struggled for a year and a half, but gradually developed my own ways of mastering the physics and mathematics that were coming at me like water from the proverbial fire hose.
By the middle of my sophomore year at Caltech, I got my feet under myself and started enjoying my studies thoroughly, and started moving through difficult material at a reasonable pace.
In the summer before my fourth college year (1961), I got a job doing theoretical astrophysics research under the inspiring mentorship of the astronomer Jesse Greenstein. The result was my first published paper, on “The Theory of Synchrotron Radiation from Stars with Dipole Magnetic Fields”.
Ever since reading One, Two, Three, … Infinity, I had been fascinated by relativity. During my fourth year at Caltech I decided that was the direction I wanted to go for my PhD, so I spent many hours in the Caltech physics library trying to read relativity articles in research journals such as Reviews of Modern Physics.
It soon became evident that by far the most interesting research on general relativity was being done by John Archibald Wheeler at Princeton University and his students, so I applied there for graduate school – despite Jesse Greenstein’s warnings that the only significant application of relativity was the expansion of the universe. In Jesse’s view, and that of many other eminent astronomers and physicists of the era, relativity was a dead end.
At Princeton, John Wheeler was an even more inspiring mentor than I expected, and his young associate Charles Misner added to the inspiration. From Wheeler and Misner I learned about black holes, neutron stars, singularities, and geometrodynamics (the ill-understood nonlinear dynamics of curved spacetime). In parallel, I sat in on the weekly research group meetings of Robert Dicke, whose focus was experiments to test general relativity; and there I met and admired postdoc Rainer (“Rai”) Weiss.
In that era, when relativity theory was far ahead of experiment and was only weakly tested, I somehow understood that the interface of the theory with experiment could become a fruitful and exciting area of research, so I not only immersed myself in Dicke’s experimental-gravity milieux; I also spent much of my first year at Princeton getting hands-on experience with experiment. In the bowels of the Princeton physics building there was a cyclotron (particle accelerator) on which, under the mentoring of assistant professor Edwin Kashy, I explored the internal structure of the nuclei of Rhodium atoms. This was rather far from relativity, but that experience (like my earlier experience with big science at Thiokol) would turn out to be extremely useful later, when I embarked on gravitational wave research.
In the summer of 1963, I spent eight weeks in a relativity summer school at the École d’Été de Physique Theorique in the French Alps. There Wheeler and Dicke gave inspiring lectures, and I met gravitational waves in depth for the first time, in lectures by Rainer Sachs (University of Texas) on the elegant, mathematical theory of the waves, and by Joseph Weber (University of Maryland) on his pioneering experimental effort to discover gravitational waves from the distant universe. I hiked with Weber in the surrounding Alps, we talked at length about his experimental program, I became a convert to the importance and possibilities of gravitational wave experiments, and I became rather fond of Weber himself.
I completed my PhD in June 1965 and spent one more postdoctoral year at Princeton, honing my theory research skills. In 1966 Willy Fowler (who would win the 1983 Nobel Prize for explaining the origin of the elements in stars) invited me back to Caltech as a postdoc, and I jumped at the opportunity. In May, while driving from Princeton to Caltech to start my new job, I stopped in Chicago for discussions with Subrahmanyan Chandrasekhar (who would share the 1983 Nobel Prize with Fowler).
Over the following decade both Fowler and Chandrasekhar made major contributions to my chosen areas of research and influenced me substantially (Fowler on relativistic stars; Chandrasekhar on black holes and gravitational waves), and both became dear friends of mine.
Early years as a Caltech professor
During my first dozen years on the Caltech faculty, 1966–1978, gravitational waves were only a modest portion of my group’s research portfolio. Our larger foci were black holes, and other astrophysical phenomena where gravity is so strong that it must be described by Einstein’s relativity laws rather than Newton’s laws – primarily neutron stars and dense, relativistic clusters of stars. My students and postdocs (sometimes with a little help from me) used general relativity to analyze the structures and astrophysical roles of these objects, and also how they would behave when disturbed – their pulsations and their emission of gravitational waves. This fed into the main thrust of our gravitational wave research: our evolving vision for the information that can be extracted from gravitational waves, when they are ultimately detected; and more broadly, our vision for the future of gravitational wave astronomy; see my Nobel Lecture.
It was my many discussions with Braginsky in 1972–1976, as well as those with Weiss, that convinced me gravitational wave detection was truly feasible and led me in 1976 to propose to Caltech that we create a research group working on gravitational wave experiment. My first choice to lead our Caltech group was Braginsky. After many months of struggling with the idea of moving from Moscow to Caltech, he told me No. Even if he managed to get himself and his family through the iron curtain to California, the consequences for his professional colleagues and friends left back in Moscow could be dire, he thought.
When I asked Braginsky whom we should go after to lead the Caltech effort, at the top of his list was the same person as Weiss suggested to me: Ronald Drever of the University of Glasgow. Why? Because of Drever’s high creativity and his experimental insights. (For example, Drever had already proposed operating the arms of gravitational interferometers as Fabry-Perot cavities, which has turned out to be a major improvement on Weiss’s original design.) So, I suggested Drever to the Caltech physics and astronomy faculty, and after many months of learning about him and other candidates, they chose him to initiate our new experimental effort. The Caltech administration made him an offer which after many many more months, in 1979, he ultimately accepted. The next year we recruited Stan Whitcomb from the University of Chicago to assist Drever in leading our experimental effort. (Today Whitcomb is the LIGO Laboratory’s Chief Scientist.)
As a precursor to Drever’s acceptance, the Caltech administration pledged roughly two million dollars of Caltech’s own private funds for the construction of laboratories and equipment for the new experimental group, including, most importantly, funds toward a prototype gravitational interferometer with 40-meter arms.
This was the first substantial investment in gravitational interferometer research by any institution in the US: Neither MIT (Weiss’s home institution) nor the National Science Foundation had yet been willing to commit significant funds for such research. With Caltech on board, Weiss, Drever, and I, working with NSF’s Richard Isaacson, were able to trigger significant NSF funding from 1979 onward.
I take great pride in Caltech’s early and enthusiastic commitment to this field and unwavering support from the 1970s through today. Caltech’s atmosphere of collegiality, intellectual ferment, and easy communication across fields of science, and our administration’s enthusiastic efforts to help us find the funding needed for realizing our dreams, have anchored me to Caltech throughout my career, as they also anchored Richard Feynman and many others of my colleagues.
In 1984 – building on successes with the interferometer prototypes at MIT, Caltech, Glasgow and Garching, and building on a feasibility study for kilometer-sized interferometers that Weiss and his MIT group and Whitcomb had carried out – Drever, Weiss and I founded LIGO as a Caltech/MIT collaboration. MIT was unwilling to make any substantial institutional commitment to LIGO until a few years later, so Caltech became our collaboration’s lead institution. Weiss and Barish sketch the subsequent history of LIGO in their parts of our joint Nobel Lecture.
In the early 1990s, under Vogt’s leadership, we secured approval from NSF for LIGO’s construction and we took major steps toward construction. Then in 1994–2001, our second director, Barry Barish, transformed LIGO from a small Caltech/MIT project into a large international collaboration, and led us through the construction of LIGO’s facilities, the installation of LIGO’s first interferometers, and the writing of a proposal for the advanced interferometers that have now succeeded in discovering gravitational waves; see Barish’s part II of our joint Nobel Lecture.
To help educate the many hundreds of scientists who joined the LIGO effort in the late 1990s and the 2000s, I created in 2002 an online course in gravitational-wave physics that included videos of lectures about all aspects of the field, by the best experts.
By 2002, it seemed to me that I was no longer much needed within the LIGO Project. The students and postdocs I had trained, and other LSC theorists, could play the roles that I had been playing, and could do it at least as well I, if not better. So, with a sigh of relief (because by personality I did not really like working in a large project), I left day to day involvement with LIGO, and focused my attention largely on building at Caltech a research effort on computer simulations of colliding black holes and other sources of gravitational waves; see my Nobel Lecture for details.
The credit for that ultimate success, and for all the rich insights about the universe that have begun to flow from it, belongs largely to the younger generation of LIGO/Virgo scientists and engineers, and also to my Nobel Prize co-laureates Rai Weiss and Barry Barish, who have continued to make major contributions in the Advanced-LIGO era.
I continue to help the LIGO Project whenever called on for help, but that is less and less often as time passes (and almost entirely on political issues and not technical issues).
A new career at the interface of science and the arts
Since 2009 I have turned much of my effort in a very different direction: collaborations about science with artists, musicians and film makers.
Christopher Nolan’s movie Interstellar was one fruit of this, and with Stephen Hawking and my long-time Hollywood partner, Lynda Obst, I have a second science-inspired movie in the works. With the painter Lia Halloran, I am working on a book about the Warped Side of the Universe (objects and phenomena made largely or wholly from warped spacetime, most of them sources of gravitational waves). And I have been doing an occasional multimedia concert about the Warped Side of the Universe with composer Hans Zimmer and visual effects gurus Paul Franklin and Oliver James, using beautiful videos generated by numerical relativity physicists. I take great pleasure in these collaborations with brilliant and creative artists, who bring to our joint work talents and insights quite different from my own. These collaborations are my attempt to inspire nonscientists and especially young people about the beauty and power of science, in the same way as George Gamow’s book One, Two Three, … Infinity inspired me, 65 years ago.
Thorne returned to Princeton to accept the Madison Medal in 2020
Inspiration, Thorne said, was “the most important thing I got from Princeton.” It came from towering faculty members such as John Archibald Wheeler. Thorne recalled his first meeting with Wheeler, in which “he gave me a personal, 90-minute lecture, in the form of a conversation,” explaining his theory of the “fiery marriage” between general relativity and Einstein’s laws of warped spacetime. As a graduate student, Thorne also was enthralled by the experimental work of Professor Robert Dickie, a pioneer in the field of experimental gravity.
While citing those who inspired him, Thorne also spoke about his efforts to inspire others, sometimes through nontraditional means, such as consulting on the science-fiction film Interstellar (and writing a companion book about the science behind it). His latest project is a book of physics-inspired poems, illustrated by the painter Lia Halloran.
• From The Nobel Prizes 2017. Published on behalf of The Nobel Foundation by Science History Publications/USA, division Watson Publishing International LLC, Sagamore Beach, 2018. This autobiography/biography was written at the time of the award and later published in the book series Les Prix Nobel/ Nobel Lectures/The Nobel Prizes. Copyright The Nobel Foundation 2017: Kip S. Thorne – Biographical. NobelPrize.org. Nobel Prize Outreach AB 2022