{ "id": "0810.5772", "version": "v1", "published": "2008-10-31T19:40:21.000Z", "updated": "2008-10-31T19:40:21.000Z", "title": "An algebraic approach to laying a ghost to rest", "authors": [ "M. C. Nucci", "P. G. L. Leach" ], "comment": "8 pages", "journal": "Phys.Scripta 81:055003,2010", "doi": "10.1088/0031-8949/81/05/055003", "categories": [ "math-ph", "math.MP", "quant-ph" ], "abstract": "In the recent literature there has been a resurgence of interest in the fourth-order field-theoretic model of Pais-Uhlenbeck \\cite {Pais-Uhlenbeck 50 a}, which has not had a good reception over the last half century due to the existence of {\\em ghosts} in the properties of the quantum mechanical solution. Bender and Mannheim \\cite{Bender 08 a} were successful in persuading the corresponding quantum operator to `give up the ghost'. Their success had the advantage of making the model of Pais-Uhlenbeck acceptable to the physical community and in the process added further credit to the cause of advancement of the use of ${\\cal PT} $ symmetry. We present a case for the acceptance of the Pais-Uhlenbeck model in the context of Dirac's theory by providing an Hamiltonian which is not quantum mechanically haunted. The essential point is the manner in which a fourth-order equation is rendered into a system of second-order equations. We show by means of the method of reduction of order \\cite {Nucci} that it is possible to construct an Hamiltonian which gives rise to a satisfactory quantal description without having to abandon Dirac.", "revisions": [ { "version": "v1", "updated": "2008-10-31T19:40:21.000Z" } ], "analyses": { "keywords": [ "algebraic approach", "pais-uhlenbeck", "satisfactory quantal description", "fourth-order field-theoretic model", "abandon dirac" ], "tags": [ "journal article" ], "publication": { "journal": "Physica Scripta", "year": 2010, "month": "May", "volume": 81, "number": 5, "pages": "055003" }, "note": { "typesetting": "TeX", "pages": 8, "language": "en", "license": "arXiv", "status": "editable", "inspire": 801272, "adsabs": "2010PhyS...81e5003N" } } }