{ "id": "cond-mat/9510146", "version": "v4", "published": "1995-10-25T17:57:53.000Z", "updated": "1997-04-10T16:38:26.000Z", "title": "Breakdown of Landau-Ginzburg-Wilson theory for certain quantum phase transitions", "authors": [ "T. Vojta", "D. Belitz", "R. Narayanan", "T. R. Kirkpatrick" ], "comment": "4 pp., REVTeX, no figs, final version as published", "journal": "Europhys. Lett. vol. 36, pp. 191-196 (1996)", "doi": "10.1209/epl/i1996-00208-x", "categories": [ "cond-mat.stat-mech" ], "abstract": "The quantum ferromagnetic transition of itinerant electrons is considered. It is shown that the Landau-Ginzburg-Wilson theory described by Hertz and others breaks down due to a singular coupling between fluctuations of the conserved order parameter. This coupling induces an effective long-range interaction between the spins of the form 1/r^{2d-1}. It leads to unusual scaling behavior at the quantum critical point in $1