More than a year ago a couple of scientists made a splash by presenting a classical algorithm that took less than a week to simulate Sycamore's circuits on a small GPU cluster. Also, their simulations produced exact results and not estimates.
This was a big runtime cut from Google's claim of 10000 years on a supercomputer to ~5 days on a small GPU cluster. The runtime can be cut further if a more computational resources are used.
As far as I know, the paper was submitted to Phys Rev journal and uploaded on Arxiv more than a year ago. However, I can't find the published version.
Does anyone know the status of the paper? Also, if the proposed algorithm turns out to be correct, does it mean we can scratch Google's claim of quantum supremacy until they repeat the experiment with more qubits, higher circuit depth and some sort of solid verification that produced results are indeed correct and not just noise?