Abstract: On February 12, 2002, Michel Devoret’s lecture entitled “The Quantum Computer: Miracle or Mirage” kicked off the 150th anniversary celebration of the Yale School of Engineering. In his abstract, Devoret asserted that while quantum mechanics had often been viewed as limiting the information one could extract from a physical system, “recent discoveries show that fundamental properties of quantum mechanics could actually be used to perform computations that would be impossible on a standard ‘classical’ computer.”

The question of whether the quantum computer is a miracle or a mirage remains, to this day, one of the most fascinating clear-cut open scientific questions of our time. In my lecture, I will explain the question and the discoveries of the 1990s that suggested that quantum computers could perform miracles, and I will present my theory of why the quantum computer is a mirage.

Quantum computation presents important challenges for applied mathematics and computer science involving modeling, computational complexity, statistics, and the relationships between theory, experiments, and engineering. I will discuss three lines of my research: correlated errors that may cause quantum computation to fail; computational-complexity arguments (beginning with joint work with Guy Kindler) suggesting that the error rates required for quantum fault tolerance may be beyond reach; and statistical analyses, with Yosi Rinott, Tomer Shoham, and Carsten Voelkmann, of experimental claims—particularly Google’s 2019 “quantum supremacy” experiment.