Why nobody can tell whether the world’s biggest quantum computer is a quantum computer
For the past several years, a Canadian company called D-Wave Systems has been selling what it says is the largest quantum computer ever built. D-Wave’s clients include Lockheed Martin, NASA, the US National Security Agency, and Google, each of which paid somewhere between $10 million and $15 million for the thing. As a result, D-Wave has won itself millions in funding and vast amounts of press coverage—including, two months ago, the cover of Time (paywall).