Particle production from nonlocal gravitational effective action

In this paper we show how the nonlocal effective action for gravity, obtained after integrating out the matter fields, can be used to compute particle production and spectra for different space-time metrics. Applying this technique to several examples, we End that the perturbative calculation of the...

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Detalles Bibliográficos
Autores: Dobado González, Antonio, López Maroto, Antonio
Tipo de recurso: artículo
Fecha de publicación:1999
País:España
Institución:Universidad Complutense de Madrid (UCM)
Repositorio:Docta Complutense
Idioma:inglés
OAI Identifier:oai:docta.ucm.es:20.500.14352/58720
Acceso en línea:https://hdl.handle.net/20.500.14352/58720
Access Level:acceso abierto
Palabra clave:53
Covariant Perturbation-Theory
Loop Effective Action
Early Universe
Inflation
Anisotropy
Field
Física (Física)
22 Física
Descripción
Sumario:In this paper we show how the nonlocal effective action for gravity, obtained after integrating out the matter fields, can be used to compute particle production and spectra for different space-time metrics. Applying this technique to several examples, we End that the perturbative calculation of the effective action up to second order in curvatures yields exactly the same results for the total number of particles as the Bogolyubov transformations method, in the case of massless scaler fields propagating in a Robertson-Walker space-time. Using an adiabatic approximation we also obtain the corresponding spectra and compare the results with the traditional WKB approximation. [S0556-2821(99)02920-3].