On the Classical Hardness of Spoofing Linear Cross-Entropy Benchmarking

  title={On the Classical Hardness of Spoofing Linear Cross-Entropy Benchmarking},
  author={Scott Aaronson and Sam Gunn},
Recently, Google announced the first demonstration of quantum computational supremacy with a programmable superconducting processor. Their demonstration is based on collecting samples from the output distribution of a noisy random quantum circuit, then applying a statistical test to those samples called Linear Cross-Entropy Benchmarking (Linear XEB). This raises a theoretical question: how hard is it for a classical computer to spoof the results of the Linear XEB test? In this short note, we… Expand
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