Headline and is simply describing some technical details of the experiment. This is not the author bringing any points of contention, there is no disagreement here at all, this is merely defining the criteria for how quantum supremacy is defined.
They need to understand the D' distribution more by running the experiment on lower qubit configurations, comparing the experimentally sampled distributions with one another across qubit configurations and across multiple runs of the same qubit configurations. As it is, he says that they may not have even sampled from D'. The burden of proof is on the experimenters to quantitatively show that they did.
There were other issues raised, like Google not being quantitative enough with their claims of the gains achieved in their supremacy statement.
He also brings up a more general issue with quantum computing in correlated errors, which are described in more detail in his paper here: http://www.ma.huji.ac.il/~kalai/Qitamar.pdf
But it boils down to that qubit logic gates experience positively correlated errors, which unless corrected with quantum fault tolerance will have an impact on any result.
I hope this clears up some misconceptions. In general it is a good idea to use the principle of charity and try to address the best possible interpretation of someone's argument. This is true even more so when commenting on someone who is literally close to the top in their field.
> Achieving quantum supremacy via sampling
Headline and is simply describing some technical details of the experiment. This is not the author bringing any points of contention, there is no disagreement here at all, this is merely defining the criteria for how quantum supremacy is defined.
I highlighted his points of contention as a response to your original comment that said he is nitpicking, here: https://news.ycombinator.com/item?id=21168813
His main point of contention seems to be:
They need to understand the D' distribution more by running the experiment on lower qubit configurations, comparing the experimentally sampled distributions with one another across qubit configurations and across multiple runs of the same qubit configurations. As it is, he says that they may not have even sampled from D'. The burden of proof is on the experimenters to quantitatively show that they did.
There were other issues raised, like Google not being quantitative enough with their claims of the gains achieved in their supremacy statement.
He also brings up a more general issue with quantum computing in correlated errors, which are described in more detail in his paper here: http://www.ma.huji.ac.il/~kalai/Qitamar.pdf
But it boils down to that qubit logic gates experience positively correlated errors, which unless corrected with quantum fault tolerance will have an impact on any result.
I hope this clears up some misconceptions. In general it is a good idea to use the principle of charity and try to address the best possible interpretation of someone's argument. This is true even more so when commenting on someone who is literally close to the top in their field.