Research Interests

I am a theoretical physicist interested in gravity and quantum field theory.  Early in my career, I did computer simulations of black hole accretion disks.  By combining these models with X-ray data, astronomers can measure how fast black holes are spinning.

Currently, I have been studying a model for gravitational wave scattering in two spacetime dimensions.  Gravitational waves are ripples in spacetime caused by the motion of massive objects.  There is a two dimensional model for gravitational wave scattering which is exactly solvable, at least classically, thanks to the existance of a huge symmetry called the Geroch group.  I have been trying to understand if the quantum version of this model is also exactly solvable.  There are many puzzles that appear when one tries to combine gravity and quantum mechanics, and I hope this work sheds some light on some of those puzzles.

Over the years, I have studied other aspects of gravity.  For example, I have studied the dynamics of event horizons using a fluid model for the horizon called the membrane paradigm, and I have related the membrane paradigm to a symmetry of black hole physics called the BMS group.  I have also worked on the relationship between twistor space and integrable systems.  

Postdoctoral Experience

• 2019 - 2022 Insititute for Advanced Study (Princeton, NJ)
• 2016 - 2019 Columbia University (New York, NY)
• 2013 - 2016 MIT (Pappalardo Fellow) (Cambridge, MA)

Education

• Ph.D. Harvard Univeristy (Cambridge, MA)
• C.A.S.M. University  of Cambridge (Cambridge, UK)
• B.S. (Physics) and Honors B.A. (Mathematics), University of Rochester (Rochester, NY)

Publications

• Link: https://arxiv.org/search/?searchtype=author&query=Penna%2C+R+F