Institute for Pure and Applied Mathematics a National Science Foundation Math Institute ANNUAL at the University of California, Los Angeles FALL 2018

PURE NEWSLETTERMATHEMATICIAN GAINS NEW PERSPECTIVES WHILE SERVING ON IPAM’S SCIENCE ADVISORY BOARD

By any measure, is among ideas they bring to the table and in their In 2011, she accepted an invitation to the leaders in her field. A professor of assessment of these proposals. I always bring her expertise in this area to IPAM’s mathematics at the University of Chicago look forward to the meetings because Science Advisory Board. “At first I was and an expert in and smooth I learn so much. This experience has something of a spectator at the meetings,” dynamical systems, Wilkinson received broadened my perspective on my own Wilkinson recalls. “I was blown away the 2011 Satter Prize in Mathematics — work, and completely changed my view by the breadth of knowledge of the presented biennially by the American of how mathematicians can interact with other board members, and most of the Mathematical Society for outstanding other fields.” contributions to mathematics research by a woman in the previous six years. Wilkinson’s research focuses on the interplay between smooth dynamical But Wilkinson says she is constantly systems and other structures in pure enlightened by her experience on IPAM’s mathematics — geometric, statistical, Science Advisory Board, where she is part topological and algebraic. A dynamical of a group of scientists and mathematicians system is a closed system that evolves from wide-ranging disciplines who meet according to a predetermined set of rules; each year to evaluate and approve IPAM- examples range from the solar system to sponsored scientific programs. “These the stock market and the flow of water are individuals with some of the most from a pipe. Wilkinson was named a astonishing minds of anyone I have met,” fellow of the American Mathematical Wilkinson says. “They think deeply about Society in 2013 for her contributions to Amie Wilkinson problems and are wildly creative in the understanding such systems. University of Chicago (continued on page 7) SECOND LATINX IN MATH CONFERENCE HELD AT IPAM

On March 8–10, 2018, over 200 Latinx a high school math activity, networking and students, postdocs, professors, researchers mentoring activities, and a banquet. The in industry and government, and others Mathematical Sciences Institutes Diversity spent three days at UCLA celebrating and Initiative, with a grant from NSF, provided showcasing the contributions of the Latinx significant support for the conference. community to mathematics. Organizers Other sponsors included NSA, Facebook, Tatiana Toro (Univ. of Washington), Mariel UCLA Graduate Division, UCLA Division Vazquez (UC Davis), Federico Ardila of Physical Sciences, UCLA Office of (San Francisco State), and Ricardo Cortez Equity, Diversity and Inclusion, Elsevier, (Tulane), along with other volunteers and and University of Washington. Additional the IPAM staff, planned a wide variety of support was provided by UC Davis, UC activities for the conference attendees, Merced, and Purdue University. Videos including seven invited research lectures, a of many of the activities are available on 2018 Latinx in Math Conference panel discussion on Latinx in STEM, career IPAM’s website. n Hosted by IPAM panels, scientific sessions, a poster session,

FEATURES REGULARS OTHER

IPAM a Major Draw for Professor 2 Director’s Note 2 Upcoming Programs 6 Program Shapes Traffic Engineers 3 News and Recognition 4 Call for Proposals 6 Machine Learning for Physics 8 Frontiers Society 5 Mark Your Calendars 6 NOTE FROM DIRECTOR DIMA SHLYAKHTENKO

materials and functional nanostructures. It the highlights of the year was a conference was motivated by previous IPAM programs, showcasing and celebrating mathematical including Chemical Compound Space achievements of the Latinx community. in 2011 and Many Particle Systems and Machine Learning in 2016. Our spring Thanks to a generous gift from Mark Green 2018 long program, Quantitative Linear and his family, we were able to expand the Algebra, focused on connections between Green Family Lecture series to twice a year. quantitative finite-dimensional linearThis past year, we featured Facebook’s Yann algebra questions and a “continuum limit” LeCun and Fields Medalist Vaughan Jones. of these questions described by infinite- Other public events included the Calculus dimensional functional analysis. of Comedy, featuring a panel of math-y Dima Shlyakhtenko Hollywood scriptwriters, and a lecture by IPAM Director In addition to a short workshop on privacy French mathematician Yann Brenier on in biomedical data, IPAM hosted stand- optimal transportation theory. In looking back over my first year as IPAM alone workshops on Zimmer’s conjecture director, I can report that IPAM continues and on mathematics of deep learning. IPAM is grateful to its many donors, whose to be an amazing incubator of innovation, Demand was so high that we had to close combined generosity raised over $200,000 bringing together mathematicians registration to these workshops weeks in for the Director’s Endowment fund (which and other scientists for exciting and advance. This past summer, we offered will be matched 1:1 by the Dean of Physical impactful programs. a Graduate Summer School on mean Sciences at UCLA). Through a special field games, following a workshop on arrangement, the Dean has extended his Our fall 2017 Complex High Dimensional that topic last August. In addition to our matching program for one more year. Energy Landscapes long program focused undergraduate Research in Industrial on mathematical techniques for sampling Projects for Students (RIPS) program in Los I hope that you enjoy this Newsletter and analyzing complicated multivariable Angeles, we offered RIPS in Hong Kong (in and that you will engage with IPAM by functions. Such functions include energy partnership with HKUST), and graduate participating in a program or workshop, and electronic property landscapes of programs in Berlin (MODAL) and, our attending a public lecture, or taking part in inorganic, organic, biomolecular, and hybrid newest, Japan (Tohoku University). One of our fundraising campaign. n

IPAM’S ENVIRONMENT AND NETWORK A MAJOR DRAW FOR UCLA MATH PROFESSOR

Whether it’s a workshop lasting a few days of variations — specifically, optimization or a long program spanning several months problems in fields such as fluid mechanics, — and he has participated in both — UCLA economics and materials science. Such mathematics professor Wilfrid Gangbo problems are of particular interest when always knows the time he spends at an IPAM they come with a constraint. For example, event will be highly productive. if a bridge is being designed with a certain material, an optimization problem might “IPAM provides an environment where ask what would be the minimal mass you can focus on your research free of of a bridge to ensure stability under a any distractions,” Gangbo says. “During certain load. the time of the program you are not teaching or performing any administrative In recent years, Gangbo has concentrated responsibilities that you would typically have on a specific class of problems known in your daily academic work. And, whereas as optimal mass transportation — in its in your home institution you might have simplest formulation, how, for example, to Wilfrid Gangbo UCLA a few people whose research is in a similar transport a pile of dirt from an excavation area, at an IPAM program there are dozens site while expending the least amount from one location to another — and are of people you can interact with who have of energy. This seemingly rudimentary asked to determine the least expensive form overlapping interests, which makes for a question has generated an enormous amount much different dynamic.” of attention in the field of mathematics. of transport,” Gangbo explains. “We have “In optimal transportation you are given spent a lot of time developing a theory for Gangbo’s work focuses on the calculus a rule — the cost per unit mass of going characterizing best strategies.” (continued on next page) 2 • IPAM Newsletter Fall 2018 IPAM Newsletter Fall 2018 • 3

IPAM PROGRAM SHAPES NEW GENERATION OF TRAFFIC ENGINEERS

Raphael Stern is a PhD student at the backgrounds who all study similar problems the transportation landscape. A similar University of Illinois and a Visiting Scholar at in traffic theory. I had unprecedented access transformation is occurring now as vehicle the Institute for Software Integrated Systems, to these researchers, which allowed me to gain automation and pervasive data monitoring Vanderbilt University. insight beyond what would have been possible promise to revolutionize the field, requiring an interdisciplinary approach. Thanks to IPAM, I visited IPAM in 2015 as a PhD student in civil anywhere else. I believe that the format of I have conducted interdisciplinary work that engineering, for the program New Directions a long program, which enables this type of interaction, is one of IPAM’s greatest strengths. extends theory and the application of the in Mathematical Approaches for Traffic Flow mathematics of traffic flow. Next year, I will Management. Transportation was (and still join the faculty at the University of Minnesota. is) at a crucial stage: the emergence of new Through IPAM, I saw the important role that mathematics plays in traffic theory. The joint My desire to pursue an academic career stems technologies such as vehicle connectivity, from my experience at IPAM. automation, and shared mobility promises to work on traffic control using a small number of rapidly change the transportation landscape. autonomous vehicles that I began at IPAM with To watch a video on the Arizona With a sense of urgency, researchers from my advisor Dan Work (Civil/ECE, Vanderbilt), autonomous vehicles experiment, go to mathematics and engineering came to IPAM to Jonathan Sprinkle (ECE, Arizona), Benedetto http://www.ipam.ucla.edu/y4zdm n explore new developments in traffic modeling, Piccoli (Math, Rutgers-Camden), and estimation, and control. Benjamin Seibold (Math, Temple), led to a large experiment in Arizona that demonstrated the The long program’s workshops were designed ability of a low penetration rate of autonomous to provide the basic toolset to understand vehicles (~5%) to substantially alter the traffic mobility patterns at the level of the person, the flow and dampen traffic waves. We will discuss vehicle, the system, and the planet. I received an the results and broader implications of this excellent introduction to an interdisciplinary experiment at an upcoming IPAM workshop. approach to transportation, which has been central to the work that I have done since then. The IPAM program welcomed me into the academic community of traffic theory—a The program brought together world- community that started in the 1950s when Raphael Stern renowned researchers with different academic the construction of highways changed U. of Illinois and Vanderbilt

IPAM a Major Draw for UCLA Math Professor (continued from page 2) Optimal transportation theory was just beginning to emerge as a everything from financial markets to voting. “Many engineers in the major field of focus when Gangbo, then on the faculty at Georgia Tech U.S. had been working on this, but in the math community most of University, was approached by UCLA mathematics professor Andrea the experts have been concentrated in Europe and Canada,” Gangbo Bertozzi and invited to co-organize an IPAM program on the subject. says. “It was great to be able to gather experts from different geographic The quarter-long program, held in the spring of 2008, represented areas and fields in a way that exposed more people to this vibrant and Gangbo’s first IPAM experience, and it led to collaborations that promising area of study.” As a follow-up, Gangbo organized and spoke continue more than a decade later, including one with Alessio Figalli, at IPAM’s Graduate Summer School on mean field games in June of this who was awarded the 2018 Fields Medal for his work in this area. year. He is also co-organizer of a related long program on Hamilton- Jacobi-Bellman equations slated for spring 2020. That initial IPAM experience also proved beneficial eight years later, when Gangbo was recruited to join the UCLA faculty. “The fact that Born in Porto Novo, the capital of the Republic of Benin in West Africa, Gangbo completed undergraduate and graduate studies in Switzerland I had organized an IPAM program on optimal transportation theory before coming to the United States. He remains active in promoting at UCLA made me more visible to some of the faculty members, and math and science in Africa, especially in his country of origin. Gangbo when they learned I was interested, they didn’t need to do as much founded the EcoAfrica project, an association of scientists involved investigation as if they had never met or heard of me,” he says. “And in projects supporting African countries. He continues to organize from my point of view, knowing that UCLA had such an institute made conferences in Benin and serves on the scientific board of Benin’s center a position on the mathematics faculty extremely appealing.” for excellence in mathematics. He is also committed to promoting Gangbo has remained actively involved with IPAM since joining the diversity and inclusiveness in mathematics in the U.S. UCLA faculty in 2016. He was an organizer of the Mean Field Games Gangbo says his IPAM experiences have broadened his perspective workshop in the summer of 2017. In a mean field game, a large number on his own work. “It exposes you to a much wider community,” he of players interact in such a way that that each individual has a negligible explains. “IPAM selects top people from all over the world who can impact on the payoff of the rest of the players. The concept, introduced build on a topic and brings them together; out of that mixture, good in 2006, is now widely recognized as an important approach to studying things result.” n NEWS AND RECOGNITION

IPAM WELCOMES CONGRATULATIONS TO TONY CHAN APPOINTED MARIA D’ORSOGNA AS IPAM BOARD MEMBERS PRESIDENT OF KAUST ASSOCIATE DIRECTOR AND ORGANIZERS IPAM cofounder Dr. Tony Chan recently Maria D’Orsogna joined IPAM as its Several of IPAM’s current and former became the third president of King Abdullah Associate Director on August 1, 2018. board members and program organizers University of Science and Technology D’Orsogna is a professor of mathematics at have received national and international (KAUST). According to KAUST’s Board the California State University, Northridge recognition in the past year. In February, Chairman, H.E. Khalid Al-Falih, “Chan’s and holds an adjunct professor position Stan Osher, IPAM’s Director of Special outstanding record as a leader in higher in the Biomathematics Department in the Projects (UCLA), was elected to the National education and innovation will help us Geffen School of Medicine at UCLA. She Academy of Engineering. In April, the accomplish our ambitious goals in this received her PhD in Theoretical Physics American Academy of Arts and Sciences important time of national transformation.” from UCLA in 2003. Since 2005, she announced the election of Guillermo Sapiro Chan was the President of Hong Kong has visited IPAM numerous times as a (Duke), Arkadi Nemirovski (Georgia Tech), University of Science and Technology for ten core participant to four long programs, and Alexei Borodin (MIT). In May, Andrea years. He previously served as UCLA’s Dean a speaker at several workshops, and an Bertozzi (UCLA) and Simon Tavaré (Cancer of Physical Sciences and NSF’s Assistant academic mentor for RIPS. Her recent Research UK Cambridge Institute) were Director for Math and Physical Sciences. work focuses on mathematical models of elected to the National Academy of Sciences. He continues to serve on IPAM’s Board cell biology, multi-particle swarming, and Finally, at the ICM2018 in August, David of Trustees. social science systems, which she studies Donoho (Stanford) was presented with the using tools from statistical mechanics and Gauss Prize. applied mathematics. GREEN FAMILY LECTURES FEATURED JONES AND LECUN

A gift from former IPAM director Mark L. Green and his family started the Green Family Lecture Series in 2012. In 2017, an additional gift from the Green family allowed IPAM to offer two lecture series per year. In February, Yann LeCun Tony Chan (Facebook and NYU) gave two public KAUST lectures on artificial intelligence during a workshop that he co-organized entitled CANDÈS AWARDED Deep Learning Techniques. In May, Fields MACARTHUR PRIZE Medalist Vaughan Jones (Vanderbilt) gave Maria D’Orsogna Emmanuel Candès (Stanford) received a IPAM and CSUN the second set of lectures on planar algebra and von Neumann algebras, during the MacArthur Fellowship, better known as a Quantitative Linear Algebra program. “genius grant,” in the fall of 2017. Candès is KRA CHOSEN TO GIVE known for developing a unified framework NOETHER LECTURE The videos of these lectures are available on IPAM’s website. IPAM is thankful for addressing a range of problems in engineering and computer science, most The Association for Women into the Green family for making these notably compressed sensing. His work has Mathematics (AWM) and The American lectures possible. Mathematical Society (AMS) have chosen laid the groundwork for improvements in Professor Bryna Kra to give the AWM- many devices that make use of signal and AMS Noether Lecture at the 2019 Joint image processing methods. Candès was an Math Meetings (JMM) in Baltimore, organizer of the 2004 IPAM long program, Maryland. Kra is the Sarah Rebecca Roland Multiscale Geometry and Analysis in High Professor of Mathematics at Northwestern Dimensions. Around that time, Candès and University, and was a member of IPAM’s UCLA’s Terry Tao developed some of the key Board of Trustees from 2012 to 2015. She ideas of compressed sensing. Since then, the was selected for “her profound impact concept of sparsity has become fundamental on mathematics, both through her work in data science. Candès is a member of in the fields of dynamical systems and IPAM’s Science Advisory Board, and will give ergodic theory and through her service to Mark L. and Kathryn Kert Green the first Green Family Lectures of 2018-2019 the profession.” at IPAM in September.

4 • IPAM Newsletter Fall 2018 IPAM Newsletter Fall 2018 • 5

CONTINUED FRONTIERS SOCIETY MEMBERS 2017-2018 Board of Directors of the Society for the IPAM HOSTS “CALCULUS OF IPAM thanks everyone who joined the Frontiers COMEDY” EVENT Advancement of Chicanos and Native Society, gave to the Director’s Endowment Americans in the Sciences, the National Fund, and all others who donated to IPAM in Five writers and producers of The Academies Board on Mathematical the past year. Special thanks those who made Simpsons, Futurama, and The Big Bang Sciences and its Applications, and multi-year pledges! Theory (some of whom have advanced the American Association for the degrees in math, physics, and computer Advancement of Science Council. BENEFACTORS: ($2500+) science) shared their love of numbers at an IPAM public outreach event on IPAM WELCOMES NEW Tanya Beder and Joseph H. Bretton October 25, 2017. The event began BOARD MEMBERS John B. and Dolores Garnett with a lecture by bestselling author Mark L. and Kathryn Kert Green Simon Singh (The Simpsons and Their IPAM is pleased to announce that Brenda Scott and Monique Miller Mathematical Secrets), who examined Dietrich (Cornell) and Russ Caflisch George and Helen Oda Abe some of the mathematical nuggets (Courant Institute, NYU) have joined Ronald J. and Sharon S. Stern hidden in The Simpsons and Futurama. IPAM’s Board of Trustees, and Klaus- Mathematician Sarah Greenwald Robert Müller (TU Berlin) has joined (Appalachian State), who teaches and the Science Advisory Board. Caflisch CHAMPIONS ($1000–$2499) writes about math in popular culture, was a UCLA professor and director of moderated the panel. Tony F. and Monica K. Chan IPAM until 2017, when he was selected Virginia D. and Alfred W. Hales to lead the Courant Institute. Dietrich JUAN MEZA JOINS NSF AS Stanley J. Osher recently joined the faculty of the School of DIVISION DIRECTOR Operations Research at Cornell University. Mike R. Raugh and Vicki L. Johnson Charlie and Sandy Schwennesen The National Science Foundation Prior to that, she had a 33 year career at Leland Wilkinson and Marilyn Vogel appointed Juan Meza as the Division IBM where she led the Mathematical Director of the Division of Mathematical Sciences function in the research division. Jeannette M. Wing Sciences earlier this year. Meza was She was elected to the National Academy of Engineering in 2014. Müller is the chair Dean of Natural Sciences at UC Merced VISIONARIES ($500–$999) since 2011. He previously served as of the Machine Learning Department Department Head and Senior Scientist at TU Berlin. He has been awarded the Robert Baker of High Performance Computing Science Prize of Berlin and the Vodafone Russ Caflisch and Carol Meylan Research at Lawrence Berkeley National Innovations Award. He is a Member of the James C. and Diana K. Fraser Laboratory. Meza was a member of German National Academy of Sciences Valerie Hajdik Leopoldina and the Berlin Brandenburg IPAM’s Board of Trustees from 2009 Michael J. Hathaway to 2013, and has been a member of the Academy of Sciences. John W. and Jody A. Jacobs Dima Shlyakhtenko and Olga Radko DEAN’S MATCHING OPPORTUNITY EXTENDED! INNOVATORS ($100–$499) Allen and Joanie Clement Good news — UCLA’s Dean of Physical Sciences will match all gifts Karina L. Edmonds and multi-year pledges of any amount made to the IPAM Director’s Madison B. and Kristen L. Gray Fund Endowment for another year! We raised over $200,000 towards Eilish and Daniel Hathaway the endowment so far, including a $100,000 gift from AMD (arranged Tatiana Toro and Daniel Pollack by IPAM Trustee Alan Lee) and many gifts from individuals who recognize the important role of IPAM in the scientific community and Thanks also to our corporate, foundation and value our innovative programs. The Dean also created a matching other supporters. IPAM received gifts from AMD, program for estate giving. If you wish to be part of this campaign, Air Force Research Lab, Google, GumGum, please donate online at ipam.ucla.edu/donate or use the enclosed HRL, Microsoft, Praedicat, and The Aerospace envelope. If you wish to make a multi-year pledge, please contact Corporation, as well as the Breast Cancer Sharon Chang at [email protected]. Gifts of $5,000 or more Research Foundation, J.B. Berland Foundation and Julian Schwinger Foundation for Physics will be acknowledged on IPAM’s upcoming donor wall. Research. IPAM receives grants from the Simons Foundation and NSF’s Office of International You can still “name a seat” in IPAM’s lecture hall with a gift of $1,500, as Science and Engineering, in addition to our main well! Read more about the IPAM’s giving opportunities and fundraising NSF grant. Special thanks to our Latinx in Math priorities on our website. Conference sponsors, listed on the first page. UPCOMING PROGRAMS CALL FOR PROPOSALS

IPAM seeks proposals from the school proposals are comparable to those LONG PROGRAMS mathematical, statistical, and scientific for winter workshops. communities for long programs, winter Science at Extreme Scales: Where Big workshops, summer schools, and LONG PROGRAMS Data Meets Large-Scale Computing exploratory workshops. Proposals are September 12–December 14, 2018 reviewed by IPAM’s Science Advisory Long Programs generally have Board (SAB) at its annual meeting in two complementary streams: one

November. To receive full consideration, mathematical and one (or more) from Geometry and Learning from Data please send your program idea to the other related scientific disciplines where in 3D and Beyond IPAM Director at [email protected] there is the potential for a fruitful and March 11–June 14, 2019 by October 1. exciting interaction. Alternatively, this might be an interaction between two Machine Learning for Physics WINTER WORKSHOPS disparate branches of mathematics. and the Physics of Learning A long program opens with tutorials, September 4–December 8, 2019 Winter workshops are typically five days followed by three or four one-week in length, with 20–25 presentations. workshops and a culminating workshop. High Dimensional Hamilton-Jacobi PDEs The proposal should include a short March 9–June 12, 2020 description of the mathematical and The proposal should include a brief scientific content, names of individuals description of the topic, names of individuals to serve on the organizing WORKSHOPS to serve on the organizing committee, and names of individuals that you would committee, and a preliminary list of faculty, postdocs, graduate students, Analysis and Geometry of like to invite as speakers or participants. and representatives of industry and Random Shapes The SAB will consider proposals for winter 2020 at its upcoming meeting. government you would like to invite. January 7–11, 2019 Proposals for workshops on multiscale A long program proposal template is available online. Proposals for academic Women in Mathematics and physics will be considered for inclusion in a series of workshops made possible by year 2020–2021 will be reviewed at the Public Policy an endowment from the Julian Schwinger next SAB meeting. January 22–25, 2019 Foundation for Physics Research (JSF). EXPLORATORY WORKSHOPS Computational Challenges in SUMMER SCHOOLS Gravitational Wave Astronomy Exploratory Workshops address urgent January 28–February 1, 2019 Summer schools are one to three weeks problems that mathematics may help in length and incorporate both tutorials solve. They are two or three days long, Operator Theoretic Methods in (a series of 3–4 talks) and research and can be organized in less than a year. Dynamic Data Analysis and Control talks illustrating applications. They are The proposal should follow the guidelines February 11–15, 2019 directed toward graduate students and for winter workshops, above, and will be postdocs. The requirements for summer considered at any time. Braids, Resolvent Degree and Hilbert's 13th Problem February 19–21, 2019 Mark Your Calendars Autonomous Vehicles September 24, 2018. Emmanuel Candès (Stanford) will give two public February 25–March 1, 2019 lectures this week as part of the Green Family Lecture Series. Collaborative Workshop for Women in October 1–2, 2018. IPAM will offer an industrial short course on deep Mathematical Biology learning and the latest algorithms in artificial intelligence. June 17–21, 2019 January 28, 2019. Nobel Laureate Barry Barish (Caltech) will give two OTHER PROGRAMS public lectures this week as part of the Green Family Lecture Series.

Research in Industrial Projects February 12, 2019. Application deadline for IPAM’s undergraduate for Students (RIPS) and graduate-level Research in Industrial Projects for Students (RIPS) • Los Angeles, June 24–August 23, 2019 Programs in Los Angeles, Berlin, Sendai, and Singapore. • Berlin, June 24–August 16, 2019 • Sendai, June 17–August 9, 2019 For more information, go to www.ipam.ucla.edu. • Singapore, June 3–August 2, 2019 Stay Connected

6 • IPAM Newsletter FallFall 2018 2018 IPAM Newsletter Fall 2018 • 7 Pure Mathematician (continued from page 1) proposals were in applied math, which is tend to speak very different languages,” collaborations,” Wilkinson says. not my specialty. Then I began talking with Wilkinson says. “In the end it was generally physicists who design particle accelerators agreed among the participants that this “Some of the most interesting problems in about some of the pure mathematics workshop was really successful in bringing mathematics come from a desire to answer problems that arise in their work. Based on together colleagues in pure dynamics who fundamental questions, and it’s easy in those conversations, at the next scientific were able to talk in depth about concrete pure mathematics to lose touch with the advisory board meeting I proposed that we problems that the people who design original motivating questions that have do a workshop on the topic.” particle accelerators wanted to solve.” borne so much fruit,” Wilkinson adds. “IPAM is the place where mathematicians The result was the IPAM workshop Beam Wilkinson then co-organized a second can reconnect to the science behind these Dynamics, held in 2017 and devoted IPAM workshop that was held last January, key questions. The applied mathematics to better understanding and extending this one on a pure mathematics topic. at IPAM isn’t just solving a problem and the mathematical methods available to New Methods for Zimmer’s Conjecture then looking for a field that it might apply accelerator physicists, as well as to gaining focused on a recent breakthrough in to; it’s talking to the scientists, finding out a better grasp of ways to control the advancing the decades-old work of the what their issues are, and then bringing physics and technology of these systems, mathematician Robert J. Zimmer at the in mathematicians who are well equipped which have many industrial and medical University of Chicago. One of the central and interested in answering these applications. “I was delighted to be able to questions about Zimmer’s conjecture was questions. That makes it very rewarding come up with an idea for a workshop that recently answered by three researchers, for everyone involved.” n was applied — the IPAM ideal,” Wilkinson including two University of Chicago says. “And I know I would not have thought postdoctoral scholars. After talking with of it without my experience on the Science one of the researchers, Indiana University’s Ad v i s or y B o ard .” David Fisher, about the potential for the Beam Dynamics attracted a diverse group breakthrough to lead to new ideas that — including physicists and mathematicians, could be used to solve other problems, and ranging from academics to individuals Wilkinson proposed that they help to co- working in national laboratories. “It’s organize an IPAM workshop that would a wonderfully informal set up at these both present the new techniques and IPAM workshops, where I felt comfortable place them within a broader context of taking the microphone from time to time work that had begun in parallel fields. and asking questions that I thought would “It was fascinating, and it opened up a connect people from different fields who dialogue that led to some interesting new

BOARD OF TRUSTEES SCIENCE ADVISORY BOARD IPAM DIRECTORS

David Balaban, Navican Alexei Borodin, MIT Dima Shlyakhtenko, Director Russ Caflisch, Courant Institute, NYU Michael Brenner, Harvard Maria D'Orsogna, Associate Director Tony Chan, KAUST Emery Brown, MIT Stanley Osher, Director of Special Projects Brenda Dietrich, Cornell University Robert Calderbank, Duke University Christian Ratsch, Deputy Director Karina Edmonds, Google Emmanuel Candès, Susana Serna, RIPS Director Mark Green, UCLA Cecilia Clemente, Rice University Alfred Hales, CCR La Jolla Cynthia Dwork, Sallie Keller, Virginia Tech University Jordan Ellenberg, University of Wisconsin NEWSLETTER Steven Koonin, NYU Peter W. Jones, Yale University Stacy Orozco, Editor/Designer Alan Lee, AMD Yann LeCun, Facebook and NYU Stacey Beggs, Raphael Stern, and Monique Miller, Euclidean Capital David Levermore (Chair), Univ. of Maryland Dan Gordon, Contributors Nancy Potok, Office of Management & Budget Xihong Lin, Harvard University Ronald Stern (Chair), UC Irvine Klaus-Robert Müller, TU Berlin Tatiana Toro, University of Washington Assaf Naor, Princeton University Leland Wilkinson, H2O.ai Pablo Parrilo, MIT Jeannette Wing, Columbia University Terence Tao, UCLA Luca Trevisan, UC Berkeley Amie Wilkinson, University of Chicago Institute for Pure and Applied Mathematics a National Science Foundation Math Institute at the University of California, Los Angeles

405 Hilgard Avenue Box 957121, 460 Portola Plaza Los Angeles, CA 90095 p: 310-825-4755 f: 310-825-4756 www.ipam.ucla.edu

MACHINE LEARNING FOR PHYSICS AND THE PHYSICS OF LEARNING

In fall 2019, IPAM will host a long program on the interface of inference and maximum entropy, are refinements of techniques machine learning (ML) and physics. ML is providing powerful tools invented by physicists. It is the goal of the IPAM program to push to extract essential information from experimental or simulation the cross-pollination further in the specific context of discovering data. Almost every branch of the physical sciences can make physical principles from data. n significant breakthroughs by embracing, developing and applying ML methods that interrogate high-dimensional complex data in an unprecedented way.

As yet, most applications in the physical sciences have been using rather basic ML techniques, such as fitting, clustering or classifying signals. However, ML provides exciting opportunities to learn the models themselves — i.e., to discover physical principles and structures underlying the data — and to obtain models that provide physical insight in addition to fitting the data. With more realistic constraints, ML will also be able to generate and design complex and novel physical structures.

The exchange between fields can go in both directions. Since its beginning, ML has been inspired by methods from statistical physics. Many modern machine learning tools, such as variational