Activities in 2011-2012

From the Report for Academic Year 2011-2012
of the Institute for Advanced Study

PIET HUT continued to divide his time between his research in astrophysics and his responsibilities as Head of the Program of Interdisciplinary Studies. The latter program had sixteen visitors, with durations of their visits ranging from days to weeks to months to a year, in fields including mathematical physics, astrophysics, computer science, philosophy, science writing, cognitive science, media studies, classical music, and literature studies.

During the year, Prof. Hut organized a series of After-Hour Conversations, together with colleagues Nicola Di Cosmo from the School of Historical Studies, Didier Fassin from the School of Social Science, and Helmut Hofer from the School of Mathematics. These conversation were held at IAS in Harry's Bar, two times a week for a period of two months during each semester. Each gettogether had a more formal part lasting thirty minutes, starting with a ten-minute talk by a speaker and followed by a twenty-minute period of questions. In addition, many participants would continue informal conversations afterward. These activities were widely seen as an effective way to encourage inter-School communication at IAS.

In astrophysics, together with colleagues Ataru Tanikawa and Jun Makino, Hut published a paper that described the formation of the first tight double star in the core collapse of a dense stellar system. While this process had been observed indirectly in stellar dynamics simulations going back to the nineteen sixties, as yet nobody had been able to show in miscroscopic detail how such a double star comes into being, through exactly what cascade of encounters with other stars in the core. When they showed the details of this process, through the development and application of several new software algorithms, they found that two major aspects of conventional wisdom in the formation of such double stars needed to be replaced. One was related to the unexpectedly strong role of simultaneous many-body effects, and the other to the large jumps in binding energy of double stars jockeying for position in becoming tight enough to survive.

Also in astrophysics, Hut continued to (co-)organize further meetings by the MODEST consortium (for MOdeling DEnse Stellar Systems) that he co-founded ten years earlier. The first was the MODEST-10d workshop in Kobe, Japan, entitled "High-Level Languages for Hugely Parallel Astrophysics Simulations: Dialogues between Computer Scientists and (Astro)physicists" where Hut gave the introductory talk. The second one was the MODEST-11 workshop in Leiden, Holland. The third one was the MODEST-11a workshop in Tokyo, Japan, entitled: "New Mathematical Techniques for High Performance Computing", where he also gave the introductory talk.

Examples of Hut's activities in the Program of Interdisciplinary Studies are a short series of weekly lectures by members that he organized, including talks by Monica Manolescu about "Ways of (Not) Knowing: Cartography, Art, Literature," and by Philip Ording, about "Variations on a Proof: Mathematical Exercises in Style." Another example is a talk given by Jacob Bourjaily on "The Geometry of Quantum Field Theory", in preparation for a TED talk on "Transforming the Universe" that he was asked to give later in the spring of 2012. Prof. Hut also gave the annual William Witherspoon Lecture in Theology and Science at the Center for Theological Inquiry in Princeton.

As part of his ongoing research of virtual worlds, Prof. Hut explored OpenSim, an alternative environments in addition to the more established world of Second Life. Within the latter, he organized workshops and other regular meetings for the Meta Institute for Computational Astrophysics (MICA;, and for the Kira Institute (, focused on interdisciplinary collaborations. As an example of the power of virtual worlds to reach larger audiences, in October 2011 Prof. Hut gave a lecture, followed by a discussion, on Exploring the Use of Virtual Worlds for Interdisciplinary Research, in a mixed virtual/real event organized at Exeter University in the UK in Real Life and in the European University campus in Second Life.