000150811 001__ 150811
000150811 005__ 20250214153851.0
000150811 0247_ $$2doi$$a10.1007/JHEP01(2025)113
000150811 0248_ $$2sideral$$a142854
000150811 037__ $$aART-2025-142854
000150811 041__ $$aeng
000150811 100__ $$0(orcid)0000-0003-3669-6241$$aAsorey, M.$$uUniversidad de Zaragoza
000150811 245__ $$aBound states of massive complex ghosts in superrenormalizable quantum gravity theories
000150811 260__ $$c2025
000150811 5060_ $$aAccess copy available to the general public$$fUnrestricted
000150811 5203_ $$aOne of the remarkable differences between renormalizable quantum gravity with four-derivative action and its superrenormalizable polynomial generalizations is that the latter admit a more sophisticated particle mass spectrum. Already in the simplest superrenormalizable case, the theory has a six-derivative Lagrangian, admitting either a real or complex spectrum of masses. In the case of a real spectrum, there are the graviton, massive unphysical ghosts, and normal particles with masses exceeding the ones of the ghosts. It is also possible to have pairs of complex conjugate massive ghost-like particles. We show that in both cases, these theories do not admit a Källén-Lehmann representation and do not satisfy the positivity criterium of consistency in terms of the fields associated to those particles. In the main part of the work, using a relatively simple Euclidean scalar toy model, we show that the theory with complex spectrum forms bound states confining unphysical massive excitations into a normal composite particle. Finally, we discuss the cosmological implications of such a ghost confinement.
000150811 536__ $$9info:eu-repo/grantAgreement/ES/DGA-FSE/E21-17R$$9info:eu-repo/grantAgreement/ES/MICINN/PGC2022-126078NB-C21
000150811 540__ $$9info:eu-repo/semantics/openAccess$$aby$$uhttp://creativecommons.org/licenses/by/3.0/es/
000150811 655_4 $$ainfo:eu-repo/semantics/article$$vinfo:eu-repo/semantics/publishedVersion
000150811 700__ $$aKrein, G.
000150811 700__ $$aPardina, M.$$uUniversidad de Zaragoza
000150811 700__ $$aShapiro, I.
000150811 7102_ $$12004$$2405$$aUniversidad de Zaragoza$$bDpto. Física Teórica$$cÁrea Física Teórica
000150811 773__ $$g2025 (2025), 113 [20 pp.]$$pJ. high energy phys.$$tJournal of High Energy Physics$$x1126-6708
000150811 8564_ $$s485857$$uhttps://zaguan.unizar.es/record/150811/files/texto_completo.pdf$$yVersión publicada
000150811 8564_ $$s1708765$$uhttps://zaguan.unizar.es/record/150811/files/texto_completo.jpg?subformat=icon$$xicon$$yVersión publicada
000150811 909CO $$ooai:zaguan.unizar.es:150811$$particulos$$pdriver
000150811 951__ $$a2025-02-14-14:05:12
000150811 980__ $$aARTICLE