Tommaso Guaita (Freie Universität Berlin)

Classical Simulation of Noisy Quantum Circuits using frame theory

I will present an overview of some recent ideas on how noisy quantum circuits can be simulated classically using methods based on quantum frames and quasi-probabilities. These involve expanding states or observables on a so-called 'frame' of operators and sampling trajectories through these frames. I will first review how this framework allows us to capture in a unified picture some of the currently popular ideas and methods for noisy circuit simulation. Then I will discuss how, by exploring different choices of frames within this formalism, we are able to go beyond the state of the art and discover novel simulation algorithms, such as a new method with an improved performance based on a generalization of the Pauli frame. We thereby show that classical simulation techniques can directly benefit from a perspective -- the one of frames -- that goes beyond the traditional classification of quantum resources.