6533b874fe1ef96bd12d632d
RESEARCH PRODUCT
Adiabatic regularization for Dirac fields in time-varying electric backgrounds
Silvia PlaJose Navarro-salasPau Beltrán-palausubject
High Energy Physics - TheoryPhysics010308 nuclear & particles physicsConformal anomalyScalar (mathematics)FOS: Physical sciencesField strengthGeneral Relativity and Quantum Cosmology (gr-qc)01 natural sciencesGeneral Relativity and Quantum CosmologyHigh Energy Physics - Theory (hep-th)Quantum electrodynamicsElectric fieldRegularization (physics)0103 physical sciences010306 general physicsAdiabatic processAnsatzVector potentialdescription
The adiabatic regularization method was originally proposed by Parker and Fulling to renormalize the energy-momentum tensor of scalar fields in expanding universes. It can be extended to renormalize the electric current induced by quantized scalar fields in a time-varying electric background. This can be done in a way consistent with gravity if the vector potential is considered as a variable of adiabatic order one. Assuming this, we further extend the method to deal with Dirac fields in four spacetime dimensions. This requires a self-consistent ansatz for the adiabatic expansion, in presence of a prescribed time-dependent electric field, which is different from the conventional expansion used for scalar fields. Our proposal is consistent, in the massless limit, with the conformal anomaly. We also provide evidence that our proposed adiabatic expansion for the fermionic modes parallels the Schwinger-DeWitt adiabatic expansion of the two-point function. We give the renormalized expression of the electric current and analyze, using numerical and analytical tools, the pair production induced by a Sauter-type electric pulse. We also analyze the scaling properties of the current for a large field strength.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2020-05-20 | Physical Review |