Introducing Geoff Penington

Joined the Department July, 2025

I am very excited to be returning to Stanford after previously being here as a PhD student from 2015-2020. I grew up in the south of England and was an undergraduate at the University of Cambridge, but then moved to California and quickly realized that I never wanted to leave. The UK is a wonderful place in many ways, but it doesn’t have Yosemite. After completing my PhD, I spent five years as an Assistant Professor at UC Berkeley (including two years as a Visiting Professor at the Institute for Advanced Study) before now hopping across the bay back to where I started.

My research mostly involves the theory of quantum information, quantum gravity, or a combination of the two. In particular, I have spent a lot of time thinking about the quantum mechanics of black holes. In 2019, I was involved in some exciting progress on Hawking’s famous black hole information problem. More recently, I have written several papers that use the theory of von Neumann algebras to understand the structure of observables in quantum gravity. At a broader level, I am interested in anything that helps us to understand the fundamental rules describing our universe. What physical phenomena are possible in a quantum theory? How does that change when gravity is added to the mix? Where does the classical spacetime that we live in come from and how we go beyond it?

Outside of physics, I enjoy skiing, climbing, hiking and generally anything adventurous and outdoors. I also have a side hustle in AI research. Fortunately, Stanford is perfectly located for doing all of those things!