{ "id": "2406.12728", "version": "v1", "published": "2024-06-18T15:49:21.000Z", "updated": "2024-06-18T15:49:21.000Z", "title": "Towrad mean-field bound for critical temperature on Nishimori line", "authors": [ "Manaka Okuyama", "Masayuki Ohzeki" ], "comment": "9pages, 0 figure", "categories": [ "cond-mat.dis-nn", "cond-mat.stat-mech" ], "abstract": "The critical inverse temperature of the mean-field approximation gives a lower bound of the true critical inverse temperature in a broad class of ferromagnetic spin models, which is called the mean-field bound for the critical temperature. In this study, we explore the possibility of a corresponding mean-field bound for the critical temperature in Ising spin-glass models with Gaussian randomness on the Nishimori line. On the Nishimori line, the critical inverse temperature of the mean-field approximation is given by $\\beta_{MF}^{NL}=\\sqrt{1/z}$, where $z$ denotes the coordination number. Using the Griffiths inequalities on the Nishimori line, we prove that there is zero spontaneous magnetization in the high-temperature region $\\beta < \\beta_{MF}^{NL}/2$. In other words, the true critical inverse temperature $\\beta_c^{NL}$ of the Nishimori line is always bounded by $\\beta_c^{NL} \\ge \\beta_{MF}^{NL}/2$. Unfortunately, we did not succeed in obtaining the corresponding mean-field bound $\\beta_c^{NL} \\ge \\beta_{MF}^{NL}$ on the Nishimori line.", "revisions": [ { "version": "v1", "updated": "2024-06-18T15:49:21.000Z" } ], "analyses": { "keywords": [ "nishimori line", "towrad mean-field bound", "critical temperature", "true critical inverse temperature", "corresponding mean-field bound" ], "note": { "typesetting": "TeX", "pages": 9, "language": "en", "license": "arXiv", "status": "editable" } } }