• Corpus ID: 238857008

A Theory of Quantum Subspace Diagonalization

  title={A Theory of Quantum Subspace Diagonalization},
  author={E.N. Epperly and Lin Lin and Yuji Nakatsukasa},
Quantum subspace diagonalization methods are an exciting new class of algorithms for solving large scale eigenvalue problems using quantum computers. Unfortunately, these methods require the solution of an ill-conditioned generalized eigenvalue problem, with a matrix pencil corrupted by a non-negligible amount of noise that is far above the machine precision. Despite pessimistic predictions from classical perturbation theories, these methods can perform reliably well if the generalized… 

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