The 2013-14 Faculty Research Lecturership, the 59th since the creation of the award in 1955, is awarded to Professor Joseph Polchinski. The Faculty Research Lecturer is the highest honor that UCSB bestows on a member of its faculty. Professor Polchinski has been a Professor in the Department of Physics at UCSB since 1992, at which point he was also appointed as a permanent member of the Institute for Theoretical Physics. After receiving his Ph.D. in Physics from UC Berkeley, Polchinski held appointments at the SLAC National Accelerator Laboratory (Stanford), Harvard University, and the University of Texas at Austin before arriving at UCSB.
Professor Polchinski is a theoretical physicist working on fundamental problems involving elementary particles and forces. These include finding a quantum theory of gravity and a unified theory of all forces and particles. The traditional approach to these problems involves quantum field theory. String theory is a promising approach developed more recently. Professor Polchinski has long been recognized as one of the world leaders in both of these fields. Throughout his career, he has made a series of fundamental contributions to our understanding of quantum field theory and string theory, which has resulted in a steady stream of high impact papers.
Polchinski’s numerous distinctions include membership in the prestigious National Academy of Sciences and appointments as a fellow in: the American Physical Society, the American Academy of Arts & Sciences, and the American Association for the Advancement of Sciences. His awards include the Heinemann Prize in Mathematical Physics from the American Physical Society, the Dirac Medal from the International Center for Theoretical Physics (ICTP), and the Milner Foundation’s Physics Frontier Prize. In addition, according to INSPIRE, a data base of high energy theory papers, Professor Polchinski’s 153 papers have been cited over 24,000 times, including 11 “renowned” papers, which have over 500 citations each.
According to his nominator, Professor Polchinski's most important achievement is his discovery of “D-branes” in 1995. This revolutionized our understanding of string theory and played a key role in the development of a nonperturbative formulation of the theory. It sparked a few years of extremely rapid progress which became known as the “second string revolution.” (The first string revolution was in the mid 1980’s when the theory first gained widespread interest.) D-branes are objects extended in more than one dimension, and their discovery showed that string theory was not just a theory of strings. It also led to an entirely new way of thinking about extra spatial dimensions which is now called “brane-worlds.” Professor Polchinski's paper discovering D-branes now has over 2,000 citations.
Professor Polchinski receives a great deal of praise not only from his UCSB colleagues, but also from internationally-recognized fellow physicists outside of the university. A colleague of Polchinski’s at Harvard states, “Joe is in a class of his own. His fundamental contributions range from reformulating renormalization and quantum field theory – the foundations of twentieth century physics – to the celebrated discovery of D-branes: potentially the foundation of twenty-first century physics. In between is a very long list of seminal contributions in a multitude of problems. No one has had a greater impact on modern theoretical physics than Joe.” Another of his supporters at the Institute for Advanced Study at Princeton states, “Polchinski is one of the deepest thinkers among theoretical physicists. His insightful contributions have completely changed the direction of field theory and string theory several times.”
Furthermore, his work continues to break new ground in the field in exciting ways. One of his supporters notes that there have been some exciting recent advances (during the past 18 months) in our understanding of black holes which Professor Polchinski has been right in the middle of. A paper Polchinski co-authored in 2012 showed that two widely held beliefs about quantum black holes were incompatible. The “AMPS paradox,” as it is now called, is a thought experiment that shows that in the context of black hole physics one of the fundamental principles we believe should be relaxed. Although it is not yet clear what the resolution of this paradox will be, it is widely accepted that it points to crucial and fundamental elements of quantum gravity. According to a colleague, “This paper completely shook up the field. One cannot overstate the impact that it had. In the year and a half since it appeared, it has already received over 150 citations. Four workshops have been held devoted to trying to resolve the issues it raises (at Stanford, CERN, Santa Barbara, and Princeton).”
Finally, Polchinski is – as one of his supporters describes – a “good citizen.” He is praised for participating in many public service activities (mentoring postdocs, writing letters, serving on committees, giving public talks, etc.), and for being a gifted lecturer. One of his UCSB colleagues specifically comments on his extreme concern and support for the students with whom he works: “He spends an immense amount of time talking to his own research students and often encourages them to publish the result of such discussions without listing him as an author. When it comes to courses, the same graduate students will return to his lectures (on the same topics!) year after year in order to glean further levels of insight into what some might consider basic material in the field. Joe is always happy to accommodate these students, and to spend hours after class answering their more advanced questions.”