|   | 
Details
   web
Records
Author (up) Landete, A.; Navarro-Salas, J.; Torrenti, F.
Title Adiabatic regularization for spin-1/2 fields Type Journal Article
Year 2013 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 88 Issue 6 Pages 061501 - 5pp
Keywords
Abstract We extend the adiabatic regularization method to spin-1/2 fields. The ansatz for the adiabatic expansion for fermionic modes differs significantly from the WKB-type template that works for scalar modes. We give explicit expressions for the first adiabatic orders and analyze particle creation in de Sitter spacetime. As for scalar fields, the adiabatic method can be distinguished by its capability to overcome the UV divergences of the particle number operator. We also test the consistency of the extended method by working out the conformal and axial anomalies for a Dirac field in a Friedmann-Lemaitre-Robertson-Walker spacetime, in exact agreement with those obtained from other renormalization prescriptions. We finally show its power by computing the renormalized stress-energy tensor for Dirac fermions in de Sitter space.
Address [Landete, Aitor] Univ Valencia, Fac Fis, Ctr Mixto Univ Valencia CSIC, Dept Fis, Burjassot 46100, Valencia, Spain
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1550-7998 ISBN Medium
Area Expedition Conference
Notes WOS:000323894000001 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 1566
Permanent link to this record
 

 
Author (up) Marañon-Gonzalez, F.J.; Navarro-Salas, J.
Title Adiabatic regularization for spin-1 fields Type Journal Article
Year 2023 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 108 Issue 12 Pages 125001 - 11pp
Keywords
Abstract We analyze the adiabatic regularization scheme to renormalize Proca fields in a four-dimensional Friedmann-Lemaitre-Robertson-Walker spacetime. The adiabatic method is well established for scalar and spin-1/2 fields, but is not yet fully understood for spin-1 fields. We give the details of the construction and show that, in the massless limit, the renormalized stress-energy tensor of the Proca field is closely related to that of a minimally coupled scalar field. Our result is in full agreement with other approaches, based on the effective action, which also show a discontinuity in the massless limit. The scalar field can be naturally regarded as a Stueckelberg-type field. We also test the consistency of our results in de Sitter space.
Address [Maranon-Gonzalez, F. Javier; Navarro-Salas, Jose] Univ Valencia, Dept Fis Teor, CSIC, Burjassot 46100, Valencia, Spain, Email: jnavarro@ific.uv.es
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2470-0010 ISBN Medium
Area Expedition Conference
Notes WOS:001121689900014 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 5871
Permanent link to this record
 

 
Author (up) Nadal-Gisbert, S.; Navarro-Salas, J.; Pla, S.
Title Low-energy states and CPT invariance at the big bang Type Journal Article
Year 2023 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 107 Issue 8 Pages 085018 - 16pp
Keywords
Abstract In this paper, we analyze the quantum vacuum in a radiation-dominated and CPT -invariant universe by further imposing the quantum states to be ultraviolet regular i.e., satisfying the Hadamard/adiabatic condition. For scalar fields, this is enforced by constructing the vacuum via the states of low-energy proposal. For spin -12 fields, we extend this proposal for a FLRW spacetime and apply it for the radiation-dominated and CPT -invariant universe. We focus on minimizing the smeared energy density around the big bang and give strong evidence that the resulting states satisfy the Hadamard/adiabatic condition. These states are then self -consistent candidates as effective big bang quantum vacuum from the field theory perspective.
Address [Nadal-Gisbert, Sergi; Navarro-Salas, Jose] Univ Valencia, Ctr Mixto Univ Valencia, CSIC Fac Fis, Dept Fis Teor, Valencia 46100, Spain, Email: sergi.nadal@uv.es;
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2470-0010 ISBN Medium
Area Expedition Conference
Notes WOS:000981997800003 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5585
Permanent link to this record
 

 
Author (up) Navarro-Salas, J.
Title Black holes, conformal symmetry, and fundamental fields Type Journal Article
Year 2024 Publication Classical and Quantum Gravity Abbreviated Journal Class. Quantum Gravity
Volume 41 Issue 8 Pages 085003 - 14pp
Keywords black holes; horizons; singularities; conformal symmetry; quantum fields; Standard Model
Abstract Cosmic censorship protects the outside world from black hole singularities and paves the way for assigning entropy to gravity at the event horizons. We point out a tension between cosmic censorship and the quantum backreacted geometry of Schwarzschild black holes, induced by vacuum polarization and driven by the conformal anomaly. A similar tension appears for the Weyl curvature hypothesis at the Big Bang singularity. We argue that the requirement of exact conformal symmetry resolves both conflicts and has major implications for constraining the set of fundamental constituents of the Standard Model.
Address [Navarro-Salas, Jose] Univ Valencia, Dept Fis Teor, IFIC, CSIC, E-46100 Burjassot, Valencia, Spain, Email: jnavarro@ific.uv.es
Corporate Author Thesis
Publisher IOP Publishing Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0264-9381 ISBN Medium
Area Expedition Conference
Notes WOS:001187435100001 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 6029
Permanent link to this record
 

 
Author (up) Navarro-Salas, J.; Pla, S.
Title Particle Creation and the Schwinger Model Type Journal Article
Year 2022 Publication Symmetry-Basel Abbreviated Journal Symmetry-Basel
Volume 14 Issue 11 Pages 2435 - 9pp
Keywords Schwinger model; semiclassical theory; particle creation
Abstract We study the particle creation process in the Schwinger model coupled with an external classical source. One can approach the problem by taking advantage of the fact that the full quantized model is solvable and equivalent to a (massive) gauge field with a non-local effective action. Alternatively, one can also face the problem by following the standard semiclassical route. This means quantizing the massless Dirac field and considering the electromagnetic field as a classical background. We evaluate the energy created by a generic, homogeneous, and time-dependent source. The results match exactly in both approaches. This proves in a very direct and economical way the validity of the semiclassical approach for the (massless) Schwinger model, in agreement with a previous analysis based on the linear response equation. Our discussion suggests that a similar analysis for the massive Schwinger model could be used as a non-trivial laboratory to confront a fully quantized solvable model with its semiclassical approximation, therefore mimicking the long-standing confrontation of quantum gravity with quantum field theory in curved spacetime.
Address [Navarro-Salas, Jose] Univ Valencia, Ctr Mixto Univ Valencia CSIC, Fac Fis, Dept Fis Teor & IFIC, Burjassot 46100, Valencia, Spain, Email: jnavarro@ific.uv.es
Corporate Author Thesis
Publisher Mdpi Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes WOS:000895122100001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5432
Permanent link to this record