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arXiv · 0704.3432

Quantum simulators, continuous-time automata, and translationally invariant systems

K. G. H. Vollbrecht·J. I. Cirac
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Abstract

The general problem of finding the ground state energy of lattice Hamiltonians is known to be very hard, even for a quantum computer. We show here that this is the case even for translationally invariant systems. We also show that a quantum computer can be built in a 1D chain with a fixed, translationally invariant Hamitonian consisting of nearest--neighbor interactions only. The result of the computation is obtained after a prescribed time with high probability.

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K. G. H. Vollbrecht, J. I. Cirac. 2007-05-02. Quantum simulators, continuous-time automata, and translationally invariant systems. https://doi.org/10.1103/physrevlett.100.010501

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