Waves in Modern Physics

About the lecture

In this final mini-lecture, we explore waves in the context of modern physics, focusing in particular on: (i) Einstein’s photoelectric effect, from which he concluded that light comes in discrete energy packets known as photons; (ii) the wave-like properties of photons, in particular that they have a wavelength, frequency, and phase, and replicate the interference pattern of a wave when individually passed through two slits; (iii) the analogous understanding of seeing particles as waves; (iv) the wave-like properties of electrons, including electron diffraction and interference; and (v) essential developments of quantum mechanics in the 1920s.

About the lecturer

Steven Balbus is the Savilian Professor of Astronomy at the University of Oxford and a Professorial Fellow at New College, Oxford. Before coming to Oxford, he was a Professeur des Universités in the Physics Department of the Ecole Normale Supérieure de Paris for nine years. He has also held academic positions at Princeton University, MIT, and the University of Virginia. Professor Balbus’ research interests lie in astrophysical fluid dynamics, particularly the behavior of magnetic gases. He has made distinguished contributions to our understanding of accretion disks, the dynamics of heating and cooling processes in hot plasmas, the behavior of gas in spiral galaxies, and the Sun’s internal rotation. In 2013, he was jointly awarded one of the highest honours in astronomy, the Shaw Prize, for his work on accretion disk turbulence, referred to as the magnetorotational instability. He received the Eddington Medal from the Royal Astronomical Society in 2020 and the Dirac Medal and Prize from the Institute of Physics (IoP) in 2021. Professor Balbus is a Fellow of the Royal Society and a member of the US National Academy of Sciences.