Year: 2022
Type: preprint
Abstract: More than ten years ago the author described a parameter $K(ρ)$ for the complexity of $n$-qubit quantum state $ρ$ and raised the conjecture (referred to as "Conjecture C") that when this parameter is superpolynomial in $n$, the state $ρ$ is not experimentally feasible (and will not be experimentally achieved without quantum fault-tolerance). Shortly afterward [6] (arXiv:1204.3404), Steve Flammia and Aram Harrow claimed that the simple easy-to-construct $W$ states are counterexamples to "Conjecture C." We point out that Flammia and Harrow's argument regarding $W$-states is incomplete. Moreover, the emergent picture from experimental progress of the past decade on noisy intermediate scale quantum (NISQ) computers suggests that $W$-states, as simple as they appear, cannot be achieved experimentally by NISQ computers, and can not be constructed without quantum fault-tolerance.
Source: arXiv (Cornell University)
Author: Kalai, Gil
Institutions: Reichman University, Hebrew University of Jerusalem
Language: English
Subfield: Artificial Intelligence
Field: Computer Science
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W4297632084