## LIGO Founders Receive Prestigious Kavli Prize in Astrophysics

The 2016 Kavli Prize in Astrophysics has been awarded to the three founders of the Laser Interferometer Gravitational-Wave Observatory (LIGO): Caltech's Ronald W. P. Drever, professor of physics, emeritus, and Kip S. Thorne (BS '62), the Richard P. Feynman Professor of Theoretical Physics, Emeritus; and MIT's Rainer Weiss, professor of physics, emeritus.

The $1 million prize, presented once every two years, honors the three for their instrumental role in establishing LIGO, an effort that led to the direct detection of gravitational waves—ripples in the fabric of space and time predicted a century earlier by Albert Einstein's general theory of relativity. On February 11, 2016, the international LIGO team announced the first observation of gravitational waves arriving at Earth.

The waves were generated 1.3 billion years ago when two black holes spiraled around each other and ultimately merged to form a single, more massive black hole. The twin LIGO instruments—one in Hanford, Washington, and the other in Livingston, Louisiana—detected the waves by measuring changes to the lengths of their 4-kilometer-long arms as small as one one-thousandth the width of a proton.

"The detection of tiny ripples in space and time, set up when two black holes merged more than a billion years ago, is one of the most amazing feats of the century," says Fiona Harrison, the Benjamin M. Rosen Professor of Physics and the Kent and Joyce Kresa Leadership Chair of the Division of Physics, Mathematics and Astronomy. "The LIGO project is a marvel of precision measurement, engineering, and technical ingenuity. Its founders, Kip, Rai, and Ron, and the entire LIGO team, deserve credit for this amazing discovery."

The existence of gravitational waves was predicted by Albert Einstein's 1915 general theory of relativity, but it was not until the 1960s that technological and theoretical advances made detection even possible to consider. In the 1970s, Thorne founded a research group at Caltech to study the theory of gravitational waves. Weiss had developed a design for a gravitational wave detector; he and Thorne recruited Drever, one of the leading creators of gravitational-wave interferometer prototypes, to lead what would become LIGO.

On September 14, 2015, during the first observations with the newly upgraded Advanced LIGO interferometers, LIGO detected the first signal of gravitational waves.

"The lion's share of the credit for LIGO's gravitational wave discovery belongs to the superb 1000-member LIGO team, who pulled it off," said Thorne. "They have made Weiss, Drever and me look good. And my deep thanks go out, also, to the succession of outstanding LIGO directors who provided the leadership required for success—Robbie Vogt, Stan Whitcomb, Jay Marx, David Reitze, and especially Barry Barish. Barry designed and led the transformation of LIGO from the small R&D project that Weiss, Drever and I created into the wonderfully successful big-science project that it is today."

According to the Kavli award citation, "the direct measurement of the tiny space-time ripples required the sustained vision and experimental ingenuity of Drever, Thorne and Weiss, spanning most of the last 50 years, as individual scientists and later as intellectual leaders of a team of hundreds of scientists and engineers."

The LIGO Observatories are funded by the National Science Foundation (NSF), and were conceived, built, and are operated by Caltech and MIT. The LIGO discovery team consists of the LIGO Scientific Collaboration (which includes the GEO Collaboration and the Australian Consortium for Interferometric Gravitational Astronomy) and the European Virgo Collaboration. The NSF leads in financial support for Advanced LIGO. Funding organizations in Germany (Max Planck Society), the U.K. (Science and Technology Facilities Council, STFC) and Australia (Australian Research Council) also have made significant commitments to the project.

The Kavli Prizes, established in 2008 and awarded every two years, recognize scientists for their seminal advances in three research areas: astrophysics, nanoscience, and neuroscience. Each prize consists of a scroll, a medal, and a cash award. The Kavli Prizes are presented in cooperation and partnership with the Norwegian Academy of Science and Letters and the Norwegian Ministry of Education and Research.

Past Caltech winners of the Kavli Prize in Astrophysics include Mike Brown, the Richard and Barbara Rosenberg Professor and Professor of Planetary Astronomy, who received the Kavli Prize in 2012 for work that led to a major advance in the understanding of the history of our planetary system, and Maarten Schmidt, the Frances L. Moseley Professor of Astronomy, Emeritus, who was awarded the prize in 2008 for his seminal contributions to our understanding of the nature of quasars. Other Kavli Prize recipients include alumni David C. Jewitt (MS '80, PhD '83), cowinner of the 2012 Kavli Prize for Astrophysics; James Roger Angel (MS '66), cowinner of the 2010 Kavli Prize in Astrophysics; and Caltech trustee Richard H. Scheller (PhD '80), cowinner of the 2010 Kavli Prize in Neuroscience.

## 2016 Shaw Prize Awarded to LIGO Founders

This year's Shaw Prize in Astronomy, worth $1.2 million, has been awarded to the trio of researchers who founded LIGO: Caltech's Ronald W. P. Drever, professor of physics, emeritus, and Kip S. Thorne (BS '62), the Richard P. Feynman Professor of Theoretical Physics, Emeritus; and MIT's Rainer Weiss, professor of physics, emeritus.

According to the prize announcement, the LIGO founders are being honored "for conceiving and designing the Laser Interferometer Gravitational-Wave Observatory (LIGO), whose recent direct detection of gravitational waves opens a new window in astronomy, with the first remarkable discovery being the merger of a pair of stellar mass black holes."

The existence of gravitational waves was predicted by Albert Einstein's 1915 general theory of relativity, but it was not until the 1960s that technological and theoretical advances made detection even possible to consider. In the 1970s, Thorne founded a research group at Caltech to study the theory of gravitational waves. Weiss had developed a design for a gravitational wave detector; he and Thorne recruited Drever, one of the leading creators of gravitational-wave interferometer prototypes, to lead what would become LIGO. On September 14, 2015, during the first observations with the newly upgraded Advanced LIGO interferometers, LIGO detected the first signal of gravitational waves—the result of the collision of two black holes to form a single, more massive black hole. The detection was announced on February 11, 2016.

Drever, Thorne and Weiss have also jointly received the 2016 Gruber Foundation Cosmology Prize and the 2016 Breakthrough Prize in Fundamental Physics for their contributions to LIGO.

The Shaw Prize, established in 2004, is awarded annually in three categories: Astronomy, Life Science and Medicine, and Mathematical Sciences. It "honors individuals, regardless of race, nationality, gender and religious belief, who have achieved significant breakthroughs in academic and scientific research or applications and whose work has resulted in a positive and profound impact on mankind," according to the Prize website.

The Shaw Prize is an international award managed and administered by The Shaw Prize Foundation based in Hong Kong. Mr. Shaw has also founded The Sir Run Run Shaw Charitable Trust and The Shaw Foundation Hong Kong, both dedicated to the promotion of education, scientific and technological research, medical and welfare services, and culture and the arts.

## Gilmartin Named Dean of Undergraduate Students

On July 1, 2016, Kevin Gilmartin, professor of English, will begin serving as Caltech's dean of undergraduate students.

In announcing Gilmartin's appointment, Joseph E. Shepherd, vice president for student affairs and the C. L. Kelly Johnson Professor of Aeronautics and Mechanical Engineering, described him as "an accomplished scholar and author who brings to this position twenty-five years of experience in teaching and mentoring our students, and who has shown a keen interest in the welfare of our undergraduate students in and outside of the classroom."

In his new role as dean of undergraduate students, Gilmartin will work on fostering academic and personal growth through counseling and support for student activities as well as acting as a liaison between students and faculty, says Shepherd.

A recipient the Feynman Prize, Caltech's highest teaching award, Gilmartin says he was attracted to the job of dean because "I have always found our students to be so interesting, and engaging. They are extraordinarily optimistic. They seem to have a positive attitude toward the world—they're curious, and they're open to new things. What more could you ask for?"

He says he sees his role as helping undergraduates develop and thrive. "I'm excited to work with students to help foster their intellectual and academic growth and their development as individuals," he says. "Our students are remarkably diverse and they have diverse interests. The Caltech curriculum is demanding, and focused, no doubt. But within it, and through it, our students do find so many opportunities."

He adds, "The dean's office provides essential support. But we can also encourage our students to do more than they are inclined to do, to challenge themselves, to try new things."

Gilmartin received his undergraduate degree in English from Oberlin College in 1985. He received both his MS ('86) and PhD ('91) in English from the University of Chicago, joining the faculty of Caltech in 1991.

Barbara Green, who has served as the interim dean over the past year will return to her regular position as associate dean in July. In his announcement, Shepherd thanked Green "for her work with our students and service to the Institute [and for] being so willing and committed to the success of our undergraduate student body."

## Ditch Day? It’s Today, Frosh!

Today we celebrate Ditch Day, one of Caltech's oldest traditions. During this annual spring rite—the timing of which is kept secret until the last minute—seniors ditch their classes and vanish from campus. Before they go, however, they leave behind complex, carefully planned out puzzles and challenges—known as "stacks"—designed to occupy the underclassmen and prevent them from wreaking havoc on the seniors' unoccupied rooms.

Follow the action on Caltech's Facebook, Twitter, and Instagram pages as the undergraduates tackle the puzzles left for them to solve around campus. Join the conversation by sharing your favorite Ditch Day memories and using #CaltechDitchDay in your tweets and postings.

## The Power of Entanglement: A Conversation with Fernando Brandão

Computers are a ubiquitous part of modern technology, utilized in smartphones, cars, kitchen appliances, and more. But there are limits to their power. New faculty member Fernando Brandão, the Bren Professor of Theoretical Physics, studies how quantum computers may someday revolutionize computing and change the world's cryptographic systems.

**What do you do?**

My research is in quantum information science, a field which seeks to merge two of the biggest discoveries of the last century: quantum mechanics and computer science. Particularly, I am interested in studying quantum entanglement. Entanglement is a special kind of correlations only found in quantum mechanics. We are all familiar with the concept of correlations. For example, the weather in Southern California is pretty well-correlated from one day to the next—if it is sunny today, it will likely be sunny tomorrow. Quantum systems can be correlated in an even stronger way. Entanglement was first seen as a weird feature of quantum mechanics—Einstein famously referred to it as a "spooky action at a distance." But with the advancement of quantum information science, entanglement is now seen as a physical resource that can be used in information processing, such as in quantum cryptography and quantum computing. One part of my research is to develop methods to characterize and quantify entanglement. Another is to find new applications of entanglement, both in quantum information science and in other areas of physics.

**What is a quantum computer?**

At the most basic level, computers are made up of millions of simple switches called transistors. Transistors have two states—on or off—which can be represented as the zeroes or ones that make up binary code. With a quantum computer, its basic building blocks (called qubits) can be either a one or a zero, or they can simultaneously exist as a one *and* a zero. This property is called the superposition principle and, together with entanglement and quantum interference, it is what allows quantum computers to, theoretically, solve certain problems much faster than normal, or "classical," computers could. It will take a long time until we actually have quantum computers, but we are already trying to figure out what they can do.

**What is an example of a problem only solvable by a quantum computer?**

It is a mathematical fact that any integer number can be factored into the product of prime numbers. For example, 21 can be written as 3 x 7, which are both prime numbers. Factoring a number is pretty straightforward when it is a small number, but factoring a number with a thousand digits would actually take a classical computer billions and billions of years—more time than the age of the universe! However, in 1994 Peter Shor showed that quantum computers would be so powerful that they would be able to factor numbers very quickly. This is important because many current cryptographic systems—the algorithms that protect your credit card information when you make a purchase online, for example—are based on factoring large numbers with the assumption that some codes cannot be cracked for billions of years. Quantum computing would change the way we do cryptography.

**What got you interested in quantum information?**

During my undergraduate education, I was looking online for interesting things to read, and found some lecture notes about quantum computation which turned out to be by Caltech's John Preskill [Richard P. Feynman Professor of Theoretical Physics]. They are a beautiful set of lecture notes and they were really my first contact with quantum information and, in fact, with quantum mechanics. I have been working in quantum information science ever since. And now that I'm on the Caltech faculty, I have an office right down the hall from Preskill!

**What is your background?**

I am originally from Brazil. I did my bachelors and masters degrees there in physics, and my PhD at Imperial College London. After that, I moved among London, Brazil, and Switzerland for various postdocs. Then I became faculty at University College London. Last year I was working with the research group at Microsoft, and now I am here at Caltech. The types of problems I have worked on have varied with time, but they are all within quantum information theory. It is stimulating to see how the field has progressed in the past 10 years since I started working on it.

**What are you particularly excited about now that you are at Caltech?**

I can't think of a better place than Caltech to do quantum information. There are many people working on it from different angles, for example, in the intersection of quantum information and condensed-matter physics, or high-energy physics. I am very excited that I get to collaborate with them.

**What do you like to do in your free time?**

I used to go traveling a lot, but six months ago my wife and I had a baby, so he is keeping us busy. Along with work and exercise, that basically takes up all my time.

## LIGO Founders and Team Receive Cosmology Prize

Ronald Drever, professor of physics, emeritus; Kip Thorne, Richard P. Feynman Professor of Theoretical Physics, Emeritus; Rai Weiss, MIT professor of physics, emeritus; and the Laser Interferometer Gravitational-Wave Observatory (LIGO) discovery team have been selected to receive the 2016 Gruber Foundation Cosmology Prize for their observation of gravitational waves, distortions in the fabric of spacetime. The Cosmology Prize honors a leading cosmologist, astronomer, astrophysicist, or scientific philosopher for theoretical, analytical, conceptual, or observational discoveries leading to fundamental advances in our understanding of the universe.

In a press release, the Gruber Foundation called the detection of gravitational waves a "technologically herculean and scientifically transcendent achievement."

The existence of gravitational waves was predicted by Albert Einstein's 1915 general theory of relativity, but it was not until the 1960s that technological and theoretical advances made detection even possible to consider. In the 1970s, Thorne founded a research group at Caltech to study the theory of gravitational waves. Weiss had developed a design for a gravitational wave detector; he and Thorne recruited Drever, one of the leading creators of gravitational-wave interferometer prototypes, to lead what would become LIGO. On September 14, 2015, during the first observations with the newly upgraded Advanced LIGO interferometers, LIGO detected the first signal of gravitational waves—the result of the collision of two black holes to produce a single, more massive black hole. The detection was announced on February 11, 2016.

The Gruber Foundation Cosmology Prize includes a $500,000 award, to be divided equally among Drever, Thorne, and Weiss. Each will also receive a gold medal.

Past recipients of the prize include Caltech's Charles Steidel, the Lee A. DuBridge Professor of Astronomy, who received the Gruber Prize in 2010 for his studies of the distant universe.

The award ceremony will take place on July 12 at the 21st International Conference on General Relativity and Gravitation, held at Columbia University in the City of New York.

## Ooguri Receives Chunichi Award

Hirosi Ooguri, the Fred Kavli Professor of Theoretical Physics and Mathematics and founding director of the Walter Burke Institute for Theoretical Physics, will be the 2016 recipient of the Chunichi Cultural Award. Founded in 1947 by Japanese newspaper Chunichi Shimbun to commemorate the enacting of the Japanese constitution, the award celebrates individuals or organizations who have made significant contributions to the arts, humanities, and natural or social sciences. Other awardees this year include physicist and 2015 Nobel Laureate Takaaki Kajita, poet Toru Kitagawa, and biologist Ikue Mori, each of whom will receive the 2 million yen ($20,000) prize. Previous recipients include six other Nobel laureates and one Fields medalist.

The prize honors Ooguri for the "development of innovative methods of modern mathematics in high energy theory," according to the prize citation. His research focuses on creating new theoretical tools in quantum field theory and superstring theory, which may ultimately lead to a unified theory of the forces and matter in nature. He is particularly renowned for his work on topological string theory, which has had broad applications ranging from black hole physics to algebraic geometry and knot theory in mathematics.

This April, Ooguri was elected as a fellow of the American Academy of Arts and Sciences. He is also the recipient of the Leonard Eisenbud Prize for Mathematics and Physics from the American Mathematical Society, the Nishina Memorial Prize, the Humboldt Research Award, the Simons Investigator Award, and is a fellow of the American Mathematical Society. He also received Japan's Kodansha Prize for Science Books for his popular Introduction to Superstring Theory in 2014.

Ooguri will receive the Chunichi Award at a ceremony to be held in Japan on June 3.

## Tom M. Apostol, 1923–2016

Tom M. Apostol, professor of mathematics, emeritus, passed away on May 8, 2016. He was 92.

Apostol was born in Helper, Utah, on August 20, 1923. He received his bachelor of science in chemical engineering in 1944 and a master's degree in mathematics in 1946, both from the University of Washington, Seattle. In 1948, he received his PhD in mathematics from the University of California, Berkeley. In 1950, he arrived at Caltech as an assistant professor; he was named associate professor in 1956, professor in 1962, and professor emeritus in 1992.

Apostol was the author of several influential textbooks. For more than five decades, undergraduate introductory mathematics courses at Caltech have used Apostol's two-volume text, "*Calculus*," which is often referred to by Caltech students as "Tommy 1" and "Tommy 2." These volumes, as well as many of his other textbooks in mathematical analysis and analytic number theory, have been translated into Greek, Italian, Spanish, Farsi, and Portuguese. Apostol also worked with a Caltech team that produced *The Mechanical Universe . . . and Beyond*, a 52-episode video lecture series based on *The Mechanical Universe: Introduction to Heat and Mechanics* and *Beyond the Mechanical Universe: From Electricity to Modern Physics*, the introductory physics textbooks that Apostol coauthored.

Apostol later was the creator, director, and producer of *Project MATHEMATICS!*, a series of award-winning computer animated videos that explore basic topics in high school mathematics such as the Pythagorean Theorem, scaling, sines and cosines, and the history of mathematics. The nine videos, which are still available for order through the Caltech bookstore, are estimated to have been viewed by 10 million people worldwide.

"Tom was a great scholar and a beloved teacher and mentor. Generations of Caltech students benefited from his passion and dedication," says Fiona Harrison, the Benjamin M. Rosen Professor of Physics and the Kent and Joyce Kresa Leadership Chair of the Division of Physics, Mathematics and Astronomy.

"Tom Apostol was a great human being and mathematician, and an inspiration to many. He was very famous the world over for his immense talent for mathematical exposition," says Dinakar Ramakrishnan, Caltech's Taussky-Todd-Lonergan Professor of Mathematics and executive officer for mathematics. "His books set a high standard but remained accessible to many, as decades of Caltech undergraduates would testify, while his videos have stimulated high school students to pursue the beauty of mathematics."

In 1982, Apostol received an award for teaching excellence from the Associated Students of the California Institute of Technology (ASCIT). In 1998 the Mathematical Association of America (MAA) awarded him the annual Trevor Evans Award, presented to authors of an exceptional article that is accessible to undergraduates, for his piece entitled "What Is the Most Surprising Result in Mathematics?" (Answer: the prime number theorem). In 2005, 2008, and 2010, he was awarded MMA's Lester R. Ford Award, given to recognize authors of articles of expository excellence. He additionally served as a visiting lecturer for the MMA and as a member of hits Board of Governors.

He was named as one of the inaugural class of Fellows of the American Mathematical Society in 2012.

Apostol, who was an American of Greek descent, spent four months in Greece as a visiting professor of mathematics at the University of Patras in 1978. Additionally, he spent eight years as a member of an Electoral Committee selecting faculty for the University of Crete. In 2001, he was elected as a corresponding member of the Academy of Athens.

Apostol is survived by his wife, Jane Apostol; his stepson, Stephen Goddard; his sisters, Kay Navrides and Betsie Strouzas; and his brother, John Apostol.

A memorial service is being planned for later this year.

## LIGO Team Awarded Special Breakthrough Prize in Fundamental Physics

The Selection Committee of the Breakthrough Prize in Fundamental Physics has announced a Special Breakthrough Prize in Fundamental Physics recognizing the scientists and engineers who contributed to the detection of gravitational waves by the Laser Interferometer Gravitational-wave Observatory (LIGO).

The $3 million award is being shared between two groups of laureates. The three founders of LIGO—Caltech's Ronald W. P. Drever, professor of physics, emeritus, and Kip S. Thorne, the Feynman Professor of Theoretical Physics, emeritus; and MIT's Rainer Weiss, professor of physics, emeritus—will share $1 million equally. In addition, 1,012 contributors will equally share $2 million; of these, 1,005 are the authors of the paper from the LIGO and Virgo collaborations, while the remaining seven are scientists who "made important contributions to the success of LIGO." This group of seven includes Caltech's Mark Scheel, senior research associate in physics, and Rochus E. Vogt, the R. Stanton Avery Distinguished Service Professor and Professor of Physics, Emeritus.

In announcing the special prize, Yuri Milner, one of the founders of the Breakthrough Prizes, said, "The creative powers of a unique genius, many great scientists, and the universe itself, have come together to make a perfect science story."

For more about Caltech's Breakthrough Prize in Fundamental Physics laureates, read Glitz and Qubits in the current issue of Caltech's *E&S* magazine.