{
  "annotation_id": "f20a21fa-47b4-4af8-abd7-e20430d7f656",
  "date_created": "2026-03-02T18:02:27.228000Z",
  "date_modified": "2026-03-02T18:02:27.228000Z",
  "file_hash": "224c0543bd1eed89c872f1af7cc6803f1f46d49a816251be557e2a74b7245dff",
  "private": false,
  "record": {
    "abstract": "Central to many discussion of decoherence is a master equation for the\nreduced density matrix of a massive particle experiencing scattering from its\nsurrounding environment, such as that of Joos and Zeh. Such master equations\nenjoy a close relationship with spontaneous localization models, like the GRW\nmodel. This aim of this paper is to present two derivations of the master\nequation. The first derivation is a pedagogical model designed to illustrate\nthe origins of the master equation as simply as possible, focusing on physical\nprinciples and without the complications of S-matrix theory. This derivation\nmay serve as a useful tutorial example for students attempting to learn this\nsubject area. The second is the opposite: a very general derivation using\nnon-relativistic many body field theory. It reduces to the equation of the type\ngiven by Joos and Zeh in the one-particle sector, but correcting certain\nnumerical factors which have recently become significant in connection with\nexperimental tests of decoherence. This master equation also emphasizes the\nrole of local number density as the ``preferred basis\u0027\u0027 for decoherence in this\nmodel.",
    "arxiv_id": "quant-ph/0607132",
    "authors": [
      "J. J. Halliwell"
    ],
    "categories": [
      "quant-ph"
    ],
    "doi": "10.1088/1751-8113/40/12/S11",
    "title": "Two Derivations of the Master Equation of Quantum Brownian Motion",
    "url": "https://arxiv.org/abs/quant-ph/0607132"
  },
  "schema_id": "dorsal/arxiv",
  "source": {
    "execution_id": "47e7c33e-4209-458a-8f96-b1619ed6502e",
    "id": "arXiv Dataset IDs",
    "type": "Model",
    "variant": "snapshot-2026-03-01",
    "version": "0.1.0"
  },
  "user_id": 1000002
}