The SDP value for random two-eigenvalue CSPs

  title={The SDP value for random two-eigenvalue CSPs},
  author={Sidhanth Mohanty and Ryan O'Donnell and Pedro Paredes},
  booktitle={Symposium on Theoretical Aspects of Computer Science},
We precisely determine the SDP value (equivalently, quantum value) of large random instances of certain kinds of constraint satisfaction problems, ``two-eigenvalue 2CSPs''. We show this SDP value coincides with the spectral relaxation value, possibly indicating a computational threshold. Our analysis extends the previously resolved cases of random regular $\mathsf{2XOR}$ and $\textsf{NAE-3SAT}$, and includes new cases such as random $\mathsf{Sort}_4$ (equivalently, $\mathsf{CHSH}$) and $\mathsf… 

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