You might recall that Shin, Smith, Smolin, and Vazirani posted a widely-discussed preprint a week ago, questioning the evidence for large-scale quantum behavior in the D-Wave machine. Geordie Rose responded here. Without further ado:. Even a cursory reading of our paper will reveal that Geordie Rose is attacking a straw man. To date the Boixo et al paper was the only serious evidence in favor of large scale quantum behavior by the D-Wave machine. We investigated their claims and showed that there are serious problems with their conclusions.
Their conclusions were based on the close agreement between the input-output data from D-Wave and quantum simulated annealing, and their inability despite considerable effort to find any classical model that agreed with the input-output data. In our paper, we gave a very simple classical model of interacting magnets that closely agreed with the input-output data.
The task of finding an accurate model for the D-Wave machine classical, quantum or otherwise , would be better pursued with direct access, not only to programming the D-Wave machine, but also to its actual hardware.
Rose goes on to point to a large number of experiments conducted by D-Wave to prove small scale entanglement over qubits and criticizes our paper for not trying to model those aspects of D-Wave. But such small scale entanglement properties are not directly relevant to prospects for a quantum speedup. Therefore we were specifically interested in claims about the large scale quantum behavior of D-Wave.
There was exactly one such claim, which we duly investigated, and it did not stand up to scrutiny. This entry was posted on Thursday, February 6th, at pm and is filed under Announcements , Quantum , Speaking Truth to Parallelism.
