Perimeter Public Lectures

The top quark is the heaviest known type of quark, and possibly the last. Particle physicists sometimes refer to it as the "truth” quark, not always with tongue in cheek. The top quark might be just an ordinary quark, no stranger than the "strange" one, but it might hold the key to major questions of Nature through its connection to the origin of mass, the Higgs boson, and cosmic dark matter. At the Fermi National Accelerator Laboratory outside Chicago, hundreds of these heavy quarks have been observed and some first snapshots of their behavior have been obtained. At the Large Hadron Collider at CERN, millions of the heavy quarks will be produced. This lecture will review current knowledge of the top quark and explain how this knowledge has been obtained through experiments at the giant particle accelerators. Future experiments, which might reveal the top quark's deeper mysteries, will also be described.

For centuries, scientists have attempted to identify analytical laws that underlie physical phenomena in nature. Despite today’s computing power, the process of finding natural laws and their corresponding equations has resisted automation. A key challenge to finding analytic relations automatically – that is, building an autonomous robot - is defining algorithmically what makes a correlation in observed data important and insightful. Scientists are gradually uncovering an ‘alphabet’ that can be used to describe the simplest to most complex physical systems – and by seeking dynamical invariants, researchers go from finding simple predictive models to discovering deeper natural laws. Dr. Lipson will demonstrate the process on a variety of mechanical, biological, and robotic systems.

Does quantum mechanics really tell us that particles, molecules, and maybe even cats, can be in two places at once? Does it force us to deny a reality that is independent of our observation? How can scientists disagree about what quantum mechanics means and yet still agree that it is right? Joseph Emerson, co-writer of the award-winning documentary “The Quantum Tamers”, will address these questions and then describe, drawing on preview clips from the documentary, how the weirdness of the quantum world is now being harnessed for a ‘quantum information revolution’ that includes quantum teleportation, super-secure quantum communication, and the exponential power of quantum computation.

Since its launch in 2007, the website Galaxy Zoo (www.galaxyzoo.org) has become the largest astronomical collaboration in history, involving more than 250,00 volunteers in classifying galaxies. Humans outperform computers at this kind of visual classification, and the results from Galaxy Zoo have been spectacular. As well as reviewing the intimate connections between the delicate process of galaxy formation and the evolution of our Universe, this talk will include a review of the weird and wonderful objects identified by Galaxy Zoo users and a few tales from the ups and downs of citizen science.

Einstein's theory of General Relativity has taught us that empty space (or, more precisely, spacetime) is in itself a dynamical and wonderfully rich entity for both theoretical physicists and science fiction authors alike. Although it may stretch our imagination, astrophysical observations leave little doubt that spacetime can bend, move and vibrate. If we want to explain these phenomena from an underlying microscopic and more fundamental structure, we need to bring in quantum theory, leading to even more exotic possibilities such as spacetime foam and wormholes. Do they really exist? How would we know? Are they in conflict with known physics? At least some of these questions may already be within the reach of our fundamental physical theories, not just qualitatively, but also quantitatively. In this talk, Professor Loll will share her insights into how much we know and how much we can still hope to learn about quantum gravity - the elusive quantum theory of space and time.

The Bell Curve is an extremely beautiful and elegant mathematical object that turns up – often in surprising ways – in all spheres of human life. The Curve was first used by astronomers to correct errors in their observations, but it soon found important applications in the social and medical sciences in the eighteen hundreds. Some philosophers believe that a new kind of human being was created around this time largely due to the growth of statistical reasoning in the arts and sciences. Dr. Mighton will speak about the consequences of this new way of thinking about people, and further insights from his play called “Risk”, in which he is dramatizing these ideas. The Bell Curve also figures prominently in education as our school system is based on the implicit belief that there are natural, wide bell curves in achievement in students. In this lecture, Dr. Mighton will share evidence that this belief is false and he will describe how the arts and sciences, and society in general, might benefit if we rejected this belief.

Isaac Newton is known today as one of the most profound scientists to have ever lived. Newton's discoveries in physics, optics, and mathematics overturned a variety of fundamental beliefs about nature and reshaped science in ways that are still powerfully with us. But this is only part of Newton's fascinating story. Research over the last generation has revealed that the famous scientist spent over thirty years composing, transcribing, and expounding alchemical texts, resulting in a mass of papers totaling about a million manuscript words. In fact, Newton seems to have considered himself one of an elite alchemical brotherhood, even going so far as to coin private anagrams of his name in the secretive custom of the sons of art. Despite our growing knowledge of Newton's deep involvement in alchemy, one basic question remains to be answered Why did the founder of Newtonian physics believe in alchemy, a discipline long viewed as discredited in the modern scientific world? William R. Newman's lecture will attempt to arrive at an answer to that question by providing the evidence that led seventeenth-century thinkers to an acceptance of alchemical transmutation.

Recent experimental evidence suggests that living organisms are using quantum mechanics in a sophisticated fashion to enhance the efficiency of photosynthesis. Bacteria are essentially performing a quantum computation to extract energy from light. I will show how plants and bacteria perform quantum information processing, and will discuss how living creatures engage in all sorts of quantum hanky-panky in their efforts to survive and reproduce.

Time is of philosophical interest as well as the subject of mathematical and scientific research. Even though it is a concept familiar to most, the passage of time remains one of the greatest enigmas of the universe. The philosopher Augustine once said: "What then is time? If no one asks me, I know what it is. If I wish to explain it to him who asks me, I do not know." The concept time indeed cannot be explained in simple terms. Emotions, life, and death - all are related to our interpretation of the irreversible flow of time. After a discussion of the concept of time, Prof. Mazur will review historical attempts to "stop time", that is, to capture events of very short duration and then present an overview of current research into ultrafast processes using short laser pulses.

For thousands of years people have wondered, "Are we alone?" Out of the 500 planets so far known to orbit nearby stars, about 100 transit their host stars, that is, the planet goes in front of its star as seen from Earth. The transiting planets are "goldmines" for astronomers, because the planetary sizes, masses, and atmospheres can be routinely measured. NASA's Kepler Space Telescope is further revolutionizing transiting exoplanet studies with its unprecedented photometric precision. Dr. Seager will share her unique insights as a member of the Kepler Science Team including a discussion of recent Kepler announcements. She will also share information on the pioneering technology development that will fuel the search for life on other worlds.

Did you know you could fit the entire human race in the volume of a sugar cube? Or that, if the Sun were made of bananas, it wouldn't make much difference? Or that 98 per cent of the Universe is invisible? Award-winning science writer Marcus Chown invites you to come along and discover how the Universe we live in is far stranger than anything we could possibly have invented.

Space and time are two of the universe's most fundamental elements. Relativity combines these two into the unified notion of space-time, but twistor theory goes beyond this replacing both by something entirely different, where the basic elements are the paths taken by particles of light or other particles without mass. Twistor theory has already found powerful applications in the field of high-energy physics. The creation of twistor theory was motivated with the hope that it would shed light on the foundations of quantum physics, a theory that puzzled even Einstein, particularly through the weird effects of quantum non-locality—the phenomenon whereby the behaviour of quantum particles can seem to have instantaneous effects over large distances. In this lecture, Prof. Penrose will describe a deep link between twistor theory and the simplest form of quantum non-locality and how the connection may be generalized in ways that provide a broader understanding of the phenomenon.