# Efficient classical simulation of slightly entangled quantum computations.

@article{Vidal2003EfficientCS, title={Efficient classical simulation of slightly entangled quantum computations.}, author={Guifr{\'e} Vidal}, journal={Physical review letters}, year={2003}, volume={91 14}, pages={ 147902 } }

We present a classical protocol to efficiently simulate any pure-state quantum computation that involves only a restricted amount of entanglement. More generally, we show how to classically simulate pure-state quantum computations on n qubits by using computational resources that grow linearly in n and exponentially in the amount of entanglement in the quantum computer. Our results imply that a necessary condition for an exponential computational speedup (with respect to classical computations…

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