Quantum unitary dynamics of a charged fermionic field and Schwinger effect

In quantum field theory, particle creation occurs, in general, when an intense external field, such as an electromagnetic field, breaks time translational invariance. This leads to an ambiguity in the definition of the vacuum state. In cosmological backgrounds this ambiguity has been reduced by impo...

Descripción completa

Detalles Bibliográficos
Autores: Álvarez Domínguez, Álvaro, Garay Elizondo, Luis Javier, García Heredia, David, Martín Benito, Mercedes
Tipo de recurso: artículo
Fecha de publicación:2021
País:España
Institución:Universidad Complutense de Madrid (UCM)
Repositorio:Docta Complutense
Idioma:inglés
OAI Identifier:oai:docta.ucm.es:20.500.14352/4986
Acceso en línea:https://hdl.handle.net/20.500.14352/4986
Access Level:acceso abierto
Palabra clave:Nonperturbative Effects
Gauge Symmetry
Teoría de los quanta
2210.23 Teoría Cuántica
Descripción
Sumario:In quantum field theory, particle creation occurs, in general, when an intense external field, such as an electromagnetic field, breaks time translational invariance. This leads to an ambiguity in the definition of the vacuum state. In cosmological backgrounds this ambiguity has been reduced by imposing that the quantization preserves the symmetries of the system and that the dynamics is unitarily implemented. In this work, we apply these requirements to the quantization of a massive charged fermionic field coupled to a classical time-dependent homogeneous electric field, extending previous studies done for a scalar field. We characterize the quantizations fulfilling the criteria above and we show that they form a unique equivalence class of unitarily related quantizations, which provide a well-defined number of created particles at all finite times.