# Quantum algorithm for linear systems of equations.

@article{Harrow2009QuantumAF, title={Quantum algorithm for linear systems of equations.}, author={Aram Wettroth Harrow and Avinatan Hassidim and Seth Lloyd}, journal={Physical review letters}, year={2009}, volume={103 15}, pages={ 150502 } }

Solving linear systems of equations is a common problem that arises both on its own and as a subroutine in more complex problems: given a matrix A and a vector b(-->), find a vector x(-->) such that Ax(-->) = b(-->). We consider the case where one does not need to know the solution x(-->) itself, but rather an approximation of the expectation value of some operator associated with x(-->), e.g., x(-->)(dagger) Mx(-->) for some matrix M. In this case, when A is sparse, N x N and has condition… Expand

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