{
  "annotation_id": "8e2abe66-50f6-49cd-a881-b649a63832e4",
  "date_created": "2026-03-02T18:02:03.430000Z",
  "date_modified": "2026-03-02T18:02:03.430000Z",
  "file_hash": "067c3befb3e55e4d0ff368bb27cfa4d1a97888af2c7e28a3060c4e1cc87da654",
  "private": false,
  "record": {
    "abstract": "We investigate the time evolution of some models with N spins and pairwise\ncouplings, for the case of large N, in order to compare evolution times with\n\"speed limit\" minima derived in the literature. Both in a (symmetric) case with\ncouplings of the same strength between each pair and in a case of broken\nsymmetry, the times necessary for evolution to a state in which the simplest\ninitial state has evolved into a nearly orthogonal state are proportional to\n1/N, as is the speed limit time. However the coefficient in the broken symmetry\ncase comes much closer to the speed limit value. Introducing a different\ncriterion for evolution speed, based on macroscopic changes in occupation, we\nfind a corresponding enhancement in rates in the asymmetric case as compared to\nthe symmetric case.",
    "arxiv_id": "quant-ph/0312217",
    "authors": [
      "R. F. Sawyer"
    ],
    "categories": [
      "quant-ph"
    ],
    "doi": "10.1103/PhysRevA.70.022308",
    "journal_ref": "Phys.Rev. A70 (2004) 022308",
    "title": "Evolution speed in some coupled-spin models",
    "url": "https://arxiv.org/abs/quant-ph/0312217"
  },
  "schema_id": "dorsal/arxiv",
  "source": {
    "execution_id": "9ff93162-00f7-4e16-8eab-06e6486e9ca8",
    "id": "arXiv Dataset IDs",
    "type": "Model",
    "variant": "snapshot-2026-03-01",
    "version": "0.1.0"
  },
  "user_id": 1000002
}