CAP Speaker: Heliudson Bernardo

CAP Speaker

Prof. Heliudson Bernardo, Quantum Horizons Alberta Research Chair, Department of Physics & Astronomy, University of Lethbridge

The Quantum Hall Effect for Gravity: Topological Constraints on the Cosmological Constant

Abstract

I will discuss the Hall effect and the importance of topology for the quantization of the Hall conductance.

Then, I will talk about expected properties of topological theta vacua and how they can be implemented in the Wheeler-DeWitt approach to quantum gravity in the presence of a cosmological constant. I will show that consistency of those properties with the gravitational Hamiltonian constraint implies that the cosmological constant is related to a gravitational theta angle. I will also explain how the physics of the Hamiltonian constraint is analogous to the quantum Hall effect, with the cosmological constant playing the role of a quantum gravitational Hall resistivity. 

Bio

Dr. Heliudson Bernardo is an Assistant Professor and Quantum Horizons Research Chair in the Department of Physics & Astronomy at the University of Lethbridge. He earned his PhD from São Paulo State University (Brazil) and completed postdoctoral appointments at McGill University and Brown University before joining the University of Lethbridge. His research focuses on theoretical cosmology and high-energy physics, spanning quantum gravity, early- and late-time cosmology, string theory, condensed matter systems, and quantum field theory in curved spacetime. His current work emphasizes the application of quantum gravity frameworks to cosmology, connections between condensed matter and dark matter models, gravitational parity violation, and foundational aspects of quantum gravity.