School of Natural Sciences
By Hanno Rein
Pluto, the ninth planet in our solar system1 was discovered in 1930, the same year the Institute was founded. While the Institute hosted more than five thousand members in the following sixty-five years, not a single new planet was discovered during the same time.
Finally, in 1995, astronomers spotted an object they called 51 Pegasi b. It was the first discovery of a planet in over half a century. Not only that, it was also the first planet around a Sun-like star outside our own solar system. We now call these planets extrasolar planets, or in short, exoplanets.
As it turns out, 51 Pegasi b is a pretty weird object. It is almost as massive as Jupiter, but it orbits its host star in only four days. Jupiter, as a comparison, needs twelve years to go around the Sun once. Because 51 Pegasi b is very close to the star, its equilibrium temperature is very high. These types of planets are often referred to as “hot Jupiters.”
Since the first exoplanet was discovered, the technology has improved dramatically, and worldwide efforts by astronomers to detect exoplanets now yield a large number of planet detections each year. In 2011, 189 planets were discovered, approximately the number of visiting Members at the Institute every year. In 2012, 130 new planets were found. As of May 20 of this year, the total number of confirmed exoplanets was 892 in 691 different planetary systems.
By Boaz Katz, Subo Dong, and Doron Kushnir
On the evening of November 11, 1572, twenty-six-year-old astronomer Tycho Brahe was about to make a discovery that would change his life and consequentially boost the scientific revolution significantly. While casually staring at the night sky, he suddenly noticed a very bright unfamiliar star in the Cassiopeia constellation. The star, which was as bright as Venus, was located in the inner parts of the famous W-shaped constellation, which was well known to many common people, let alone astronomers. What Tycho saw looked like the appearance of a new star (nova stella). He was so astonished that he sought the confirmation of others to assure himself that he was not hallucinating.
Unknown to Tycho, such new stars had appeared during the previous centuries (“guest stars” in Chinese records), with a much brighter star reported in 1006. While these events were very important to astrologers, they had no lasting effect on astronomical thinking at the time. Tycho, however, realized that such an event was revolutionary. By accurately and repeatedly measuring the position of the “nova,” Tycho showed that it was much further than the moon. In one night, Tycho managed to scientifically falsify the millennia-old Aristotelian belief that anything beyond the sphere of the moon cannot change. This convinced Tycho that the “known” cosmology was wrong and motivated him to devote his life to performing measurements of stars and planets to study the “true” cosmology. His hard, lifelong work paid off. His careful measurements of the positions of the planets enabled the discovery of the law of gravity by Johannes Kepler and Isaac Newton. Kepler would later say that if Tycho’s star did nothing else, it produced a great astronomer. Yet, even Tycho and Kepler could not have appreciated that what seemed like a new star was actually an explosion of unimaginable power and that such explosions are crucial for our existence.
Derek Bermel, the Institute’s Artist-in-Residence since 2009, organized the Edward T. Cone Concert Series as well as dozens of conversations with poets, writers, composers, and musicians during his appointment, which ended in June. These included performances in Wolfensohn Hall by violinist Midori, pianist Jeremy Denk, inventive groups like eighth blackbird and the Borromeo String Quartet, as well as a reading by Broadway actors of his musical Golden Motors. He created a new series of Writers Conversations that probed the nature of creativity and collaboration with artists, poets, directors, and writers, including Steve Bodow, producer and writer for the Daily Show, poet Tracy K. Smith shortly before she won the Pulitzer Prize, and composer Stephen Sondheim who called art “a kind of puzzle.”
While at the Institute, Bermel collaborated with Helmut Hofer, Professor in the School of Mathematics, on a musical piece inspired by symplectic dynamics, a mathematical theory of dynamical systems. In February, the JACK Quartet performed Derek’s clarinet quintet “A Short History of the Universe (as related by Nima Arkani-Hamed),” inspired by lectures he attended by Arkani-Hamed, Professor in the School of Natural Sciences.
What was your approach when you first started as the Institute’s Artist-in-Residence?
I’d say my approach has been fairly consistent. I’ve always been interested to make contact with people here. I only wish that I could have gone to more lectures, seen more presentations, participated even more. The Institute is a very rich place. There’s quite a bit below the surface, and it was clear to me right from the beginning that the Faculty and Members here were all working on fascinating projects; some of them I could only grasp skeletally, nonetheless it was well worth the effort.
In early April 1972, Hugh Montgomery, who had been a Member in the School of Mathematics the previous year, stopped by the Institute to share a new result with Atle Selberg, a Professor in the School. The discussion between Montgomery and Selberg involved Montgomery’s work on the zeros of the Riemann zeta function, which is connected to the pattern of the prime numbers in number theory. Generations of mathematicians at the Institute and elsewhere have tried to prove the Riemann Hypothesis, which conjectures that the non-trivial zeros (those that are not easy to find) of the Riemann zeta function lie on the critical line with real part equal to 1⁄2.
Montgomery had found that the statistical distribution of the zeros on the critical line of the Riemann zeta function has a certain property, now called Montgomery’s pair correlation conjecture. He explained that the zeros tend to repel between neighboring levels. At teatime, Montgomery mentioned his result to Freeman Dyson, Professor in the School of Natural Sciences.
In the 1960s, Dyson had worked on random matrix theory, which was proposed by physicist Eugene Wigner in 1951 to describe nuclear physics. The quantum mechanics of a heavy nucleus is complex and poorly understood. Wigner made a bold conjecture that the statistics of the energy levels could be captured by random matrices. Because of Dyson’s work on random matrices, the distribution or the statistical behavior of the eigenvalues of these matrices has been understood since the 1960s.
Following the discovery in July of a Higgs-like boson—an effort that took more than fifty years of experimental work and more than 10,000 scientists and engineers working on the Large Hadron Collider—Juan Maldacena and Nima Arkani-Hamed, two Professors in the School of Natural Sciences, gave separate public lectures on the symmetry and simplicity of the laws of physics, and why the discovery of the Higgs was inevitable.
Peter Higgs, who predicted the existence of the particle, gave one of his first seminars on the topic at the Institute in 1966, at the invitation of Freeman Dyson. “The discovery attests to the enormous importance of fundamental, deep ideas, the substantial length of time these ideas can take to come to fruition, and the enormous impact they have on the world,” said Robbert Dijkgraaf, Director and Leon Levy Professor.
In their lectures “The Symmetry and Simplicity of the Laws of Nature and the Higgs Boson” and “The Inevitability of Physical Laws: Why the Higgs Has to Exist,” Maldacena and Arkani-Hamed described the theoretical ideas that were developed in the 1960s and 70s, leading to our current understanding of the Standard Model of particle physics and the recent discovery of the Higgs-like boson. Arkani-Hamed framed the hunt for the Higgs as a detective story with an inevitable ending. Maldacena compared our understanding of nature to the fairytale Beauty and the Beast.
“What we know already is incredibly rigid. The laws are very rigid within the structure we have, and they are very fragile to monkeying with the structure,” said Arkani-Hamed. “Often in physics and mathematics, people will talk about beauty. Things that are beautiful, ideas that are beautiful, theoretical structures that are beautiful, have this feeling of inevitability, and this flip side of rigidity and fragility about them.”