{
  "annotation_id": "d4d491e1-49fa-4b2a-873e-fdee6af44de1",
  "date_created": "2026-02-17T05:53:08.775000Z",
  "date_modified": "2026-02-17T05:53:08.775000Z",
  "file_hash": "382b52b02b9e4a31587eca28c43536425ea6a5a7dfbc5c310a3054b3daf50298",
  "private": false,
  "record": {
    "abstract": "Testing Lorentz symmetry in strong gravitational fields provides a promising probe of extensions to general relativity. The supermassive black hole Sgr~A* and the orbit of the S-stars offer a laboratory for such tests in a regime beyond weak field limit. We analyze the S2 orbital data focusing on the Schwarzschild-like black hole within bumblebee gravity, where deviations from general relativity are encoded in a single Lorentz-violating parameter $\\ell$. Using a full 14-dimensional Markov Chain Monte Carlo analysis under uniform and Gaussian priors, we obtain $\\ell = {-8.01 \\times 10^{-5}}^{+2.77 \\times 10^{-4}}_{-2.09 \\times 10^{-4}} $ and $\\ell = {1.00 \\times 10^{-5}}^{+2.90 \\times 10^{-4}}_{-2.91 \\times 10^{-4}} $ at $1\\sigma$ confidence level, respectively. These constraints are about three orders of magnitude tighter than those from Event Horizon Telescope imaging of Sgr~A*.",
    "arxiv_id": "2601.06491",
    "authors": [
      "Qi Qi",
      "Yu Sang",
      "Xiao-Mei Kuang"
    ],
    "categories": [
      "gr-qc"
    ],
    "license": "http://creativecommons.org/licenses/by/4.0/",
    "title": "Probing a Lorentz-violating parameter from orbital precession of the S2 star around the galactic centre supermassive black hole",
    "url": "https://arxiv.org/abs/2601.06491",
    "version": "v1"
  },
  "schema_id": "dorsal/arxiv",
  "source": {
    "execution_id": "045afe21-4036-4046-84c1-b8ae9bf8fd49",
    "id": "arXiv Dataset",
    "type": "Model",
    "variant": "snapshot-2026-01-17",
    "version": "0.1.0"
  },
  "user_id": 1000002
}