Colloquium Archives (before June 2017)

More recent colloquia are posted on the Physics & Astronomy Colloquia page.

Benjamin Schumacher, Physics Department, Kenyon College

Topic: "Almost Quantum Mechanics"  (Video)

ABSTRACT: Modal quantum theory is a discrete model that is similar in structure to ordinary quantum theory, but based on a finite field instead of complex amplitudes. The interpretation of this theory involves only the "modal" concepts of possibility and impossibility rather than quantitative probabilities. Despite its very simple structure, our toy model nevertheless includes many of the key features of actual quantum physics: interference, complementarity, entanglement, teleportation, the impossibility of cloning, nonclassical models of computation, and more.

Carles Badenes, Tel-Aviv University/Weizmann Institute

Topic: "The Quest for Type Ia Supernova Progenitors"  (Video)

Abstract: The identity of the progenitor systems of Type Ia Supernovae (SN Ia) has become one of the key open questions in stellar astrophysics. I will review the state of the art in SN Ia progenitors and point out the main reasons why this has remained an unsolved issue for so long. I will then describe some recent advances in the study of two kinds of objects - supernova remnants (SNRs) and binary white dwarfs (BWDs) - that are shedding new light on key aspects of the problem. SNRs and BWDs are much closer to Earth than the extragalactic SNe that are routinely discovered by automated SN searches, and they provide a radically different perspective of the SN Ia phenomenon. I will conclude by outlining some promising avenues for future research.