{
  "id": "cond-mat/0107627",
  "version": "v1",
  "published": "2001-07-31T11:14:25.000Z",
  "updated": "2001-07-31T11:14:25.000Z",
  "title": "Observable-dependence of fluctuation-dissipation relations and effective temperatures",
  "authors": [
    "Suzanne Fielding",
    "Peter Sollich"
  ],
  "comment": "4 pages, 2 figures",
  "journal": "Phys.Rev.Lett.88,050603(2002)",
  "doi": "10.1103/PhysRevLett.88.050603",
  "categories": [
    "cond-mat.stat-mech",
    "cond-mat.dis-nn"
  ],
  "abstract": "We study the non-equilibrium version of the fluctuation-dissipation theorem (FDT) within the glass phase of Bouchaud's trap model. We incorporate into the model an arbitrary observable m and obtain its correlation and response functions in closed form. A limiting non-equilibrium FDT plot (of correlator vs response) is approached at long times for most choices of m, with energy-temperature FDT a notable exception. In contrast to standard mean field models, however, the shape of the plot depends nontrivially on the observable, and its slope varies continuously even though there is a single scaling of relaxation times with age. Non-equilibrium FDT plots can therefore not be used to define a meaningful effective temperature T_eff in this model. Consequences for the wider applicability of an FDT-derived T_eff are discussed.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2001-07-31T11:14:25.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "effective temperature",
      "fluctuation-dissipation relations",
      "standard mean field models",
      "observable-dependence",
      "limiting non-equilibrium fdt plot"
    ],
    "tags": [
      "journal article"
    ],
    "publication": {
      "publisher": "APS",
      "journal": "Phys. Rev. Lett."
    },
    "note": {
      "typesetting": "TeX",
      "pages": 4,
      "language": "en",
      "license": "arXiv",
      "status": "editable"
    }
  }
}