Advanced Simulation of Quantum Computations

Advanced Simulation of Quantum Computations: Compact Representation Rather than Hardware Power

Quantum computation is a promising emerging technology which, compared to classical computation, allows for substantial speed-ups e.g. for integer factorization or database search. However, since physical realizations of quantum computers are in their infancy, a significant amount of research in this domain still relies on simulations of quantum computations on classical machines. This causes a...

Average-case complexity versus approximate simulation of commuting quantum computations

We use the class of commuting quantum computations known as IQP (instantaneous quantum polynomial time) to strengthen the conjecture that quantum computers are hard to simulate classically. We show that, if either of two plausible average-case hardness conjectures holds, then IQP computations are hard to simulate classically up to constant additive error. One conjecture relates to the hardness ...

Efficient classical simulation of slightly entangled quantum computations.

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...

Geometric Computations for Simulation

Polarization in Quantum Computations

We propose a realization of quantum computing using polarized photons. The information is coded in two polarization directions of the photons and twoqubit operations are done using conditional Faraday effect. We investigate the performance of the system as a computing device. PACS numbers: 03.65.Bz, 89.80.+h, 32.80.-t, 42.50.-p