The Human Story Lurking behind the Hofstadter Butterfly
Douglas Hofstadter is College of Arts and Sciences Professor of Cognitive Science, and Director of the Center for Research on Concepts and Cognition, at Indiana University in the US. A legendary pioneer in the field of artificial intelligence, Hofstadter is best known for his Pulitzer Prize winning debut work, Gödel, Escher, Bach: an Eternal Golden Braid, published in 1979.
Time: Mon 2018-02-19 16.00
Lecturer: Douglas Hofstadter, Indiana University, Bloomington
Location: Q1, Osquldas väg 4, KTH Campus
Thanks to this excellent luck, he (that is to say, yours truly, aka “I”) soon discovered a visually riveting new type of quantum-mechanical energy spectrum — a graph made out of an infinite number of smaller copies of itself (giving rise to a dizzying infinite regress) — which revealed, among other things, that both number theory and topology, contrary to what most physicists had thought, play key roles in certain areas of physics. In the following decades, this exotic graph became well known, acquiring the nickname of “Hofstadter butterfly”, and it cropped up in numerous new contexts, especially in connection with the quantum Hall effect. In recent years, certain aspects of the butterfly have just started to become empirically testable.
The lecture will recount the human story of this 40-year-old discovery, a tale rife with emotional twists and turns. In the talk there will be some technical parts (Bloch bands and Hamiltonians and wave functions and such things), but even so, much of it will be accessible to non-physicists; all that is needed is a sense of curiosity about the laws of nature and a sympathy for the idea that beauty must play a key role therein.