Scaling considerations in ground-state quantum computation

We study design challenges associated with realizing a ground-state quantum computer. In such a computer, it is necessary that the energy gap between the ground state and first excited state be sufficiently large to prevent disruptive excitations. Here, an estimate of this gap is provided as a function of computer size. We then address the problem of detecting the output of a ground-state quantum computer. It is shown that the exponential detection difficulties that appear to be present at first can be overcome by small design changes