> From a very amateur perspective, it looked like Gil Kalai was arguing that physical realizations would not be impossible, but work at UIST and Google's "quant

> From a very amateur perspective, it looked like Gil Kalai was arguing that physical realizations would not be impossible, but work at UIST and Google's "quantum supremacy" result, somehow have proved him wrong ? I assume you meant "would be impossible"? At any rate, from my slightly less amateurish understanding of the subject, I think that the main contrast between Kalai's claims and Google's results boils down to the following: - broadly speaking, Kalai is referring to pure quantum computation, more specifically he is computing limits about the efficiency and energy requirements of computers that work exclusively using quantum/linear logic; - Google's experiment made extensive use of classical computation, and it's unclear to what extent quantum computation actually impacted the result (to the point that some people claim that the entire experiment could be performed classically, see e.g. [1]) Unfortunately, many of the nuances in the debate are lost on me--in the past, I had some forays into the physics and mathematics of QC but was ultimately driven away from the dumb money flowing around--but I would recommend Gil Kalai's blog [2] as it is both accessible and rigorous (albeit being obviously biased toward one side of the argument). [1] https://arxiv.org/abs/2103.03074 https://arxiv.org/abs/2103.03074 [2] https://gilkalai.wordpress.com/ https://gilkalai.wordpress.com/