Abstract:

Barren plateaus have emerged as a pivotal challenge for variational quantum computing. Recently, our understanding of this phenomenon underwent a transformative shift with the introduction of an algebraic theory that provides exact loss variance formulas for deep parametrized quantum circuits and that is capable of explaining most sources of barren plateaus from a unified perspective [1,2]. In this talk, I will review these recent results and comment on their impact and applications. Ultimately, we expect a precise understanding of the barren plateau mechanism will help us anticipate the place variational quantum algorithms will have in near and long term quantum computing.

[1] Ragone et al, A unified theory of barren plateaus for deep parametrized quantum circuits, arXiv:2309.09342 (2023).

[2] Diaz et al, Showcasing a Barren Plateau Theory Beyond the Dynamical Lie Algebra, arXiv:2310.11505 (2023).