Barceló, C.Garay Elizondo, Luis Javier2023-06-202023-06-201998-080218-271810.1142/S0218271898000425https://hdl.handle.net/20.500.14352/59540© World Scientific. We are very grateful to Guillermo A. Mena Marugán, Mariano Moles and Pedro F. González-Díaz for helpful discussions and suggestions. C.B was supported by a Spanish Ministry of Education and Culture (MEC) grant. C.B. is also grateful to James Hartle and the Institute for Theoretical Physics (UCSB), where part of this work was done, for warm hospitality. This research was supported in part by the National Science Foundation under Grant No. PHY94–07194. L.J.G. was supported by funds provided by DGICYT and MEC under Contract Adjunct to the Project No. PB94–0107.The effects of asymptotically anti-de Sitter wormholes in low-energy field theory are calculated in full detail for three different matter contents: a conformal scalar field, an electromagnetic field and gravitons. There exists a close relation between the choice of vacuum for the matter fields and the selection of a basis of the Hilbert space of anti-de Sitter wormholes. In the presence of conformal matter (i.e., conformal scalar or electromagnetic fields), this relation allows us to interpret the elements of these bases as wormhole states containing a given number of particles. This interpretation is subject to the same kind of ambiguity in the definition of particle as that arising from quantum field theory in curved spacetime. In the case of gravitons, owing to the nonconformal coupling, it is not possible to describe wormhole states in terms of their particle content.engjournal articlehttp://dx.doi.org/10.1142/S0218271898000425http://www.worldscientific.comhttp://arxiv.org/pdf/gr-qc/9803035v1.pdfopen access51-73Baby universesPerturbationsVacuumStatesFísica-Modelos matemáticosFísica matemática