# Computational complexity of the ground state energy density problem

@article{Watson2022ComputationalCO, title={Computational complexity of the ground state energy density problem}, author={James D Watson and Toby S. Cubitt}, journal={Proceedings of the 54th Annual ACM SIGACT Symposium on Theory of Computing}, year={2022} }

We study the complexity of finding the ground state energy density of a local Hamiltonian on a lattice in the thermodynamic limit of infinite lattice size. We formulate this rigorously as a function problem, in which we request an estimate of the ground state energy density to some specified precision; and as an equivalent promise problem, GSED, in which we ask whether the ground state energy density is above or below specified thresholds. The ground state energy density problem is unusual, in…

## 3 Citations

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