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Author Agullo, I.; Navarro-Salas, J.; Olmo, G.J.; Parker, L.
Title Acceleration radiation, transition probabilities and trans-Planckian physics Type Journal Article
Year 2010 Publication New Journal of Physics Abbreviated Journal New J. Phys.
Volume 12 Issue Pages (up) 095017 - 18pp
Keywords
Abstract An important question in the derivation of the acceleration radiation, which also arises in Hawking's derivation of black hole radiance, is the need to invoke trans-Planckian physics in describing the creation of quanta. We point out that this issue can be further clarified by reconsidering the analysis in terms of particle detectors, transition probabilities and local two-point functions. By writing down separate expressions for the spontaneous-and induced-transition probabilities of a uniformly accelerated detector, we show that the bulk of the effect comes from the natural (non-trans-Planckian) scale of the problem, which largely diminishes the importance of the trans-Planckian sector. This is so, at least, when trans-Planckian physics is defined in a Lorentz-invariant way. This analysis also suggests how one can define and estimate the role of trans-Planckian physics in the Hawking effect itself.
Address [Agullo, Ivan; Olmo, Gonzalo J.; Parker, Leonard] Univ Wisconsin, Dept Phys, Milwaukee, WI 53201 USA, Email: ivan.agullo@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 1367-2630 ISBN Medium
Area Expedition Conference
Notes ISI:000284766400006 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ elepoucu @ Serial 318
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Author Beltran-Palau, P.; del Rio, A.; Nadal-Gisbert, S.; Navarro-Salas, J.
Title Note on the pragmatic mode-sum regularization method: Translational-splitting in a cosmological background Type Journal Article
Year 2021 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 103 Issue 10 Pages (up) 105002 - 9pp
Keywords
Abstract The point-splitting renormalization method offers a prescription to calculate finite expectation values of quadratic operators constructed from quantum fields in a general curved spacetime. It has been recently shown by Levi and Ori that when the background metric possesses an isometry, like stationary or spherically symmetric black holes, the method can be upgraded into a pragmatic procedure of renormalization that produces efficient numerical calculations. In this paper we show that when the background enjoys three-dimensional spatial symmetries, like homogeneous expanding universes, the above pragmatic regularization technique reduces to the well-established adiabatic regularization method.
Address [Beltran-Palau, Pau; Nadal-Gisbert, Sergi; Navarro-Salas, Jose] Univ Valencia, Dept Fis Teor, Ctr Mixto, CSIC,Fac Fis, Valencia 46100, Spain, Email: pau.beltran@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:000655874400009 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4845
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Author del Rio, A.; Ferreiro, A.; Navarro-Salas, J.; Torrenti, F.
Title Adiabatic regularization with a Yukawa interaction Type Journal Article
Year 2017 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 95 Issue 10 Pages (up) 105003 - 19pp
Keywords
Abstract We extend the adiabatic regularization method for an expanding universe to include the Yukawa interaction between quantized Dirac fermions and a homogeneous background scalar field. We give explicit expressions for the renormalized expectation values of the stress-energy tensor < T-mu nu > and the bilinear <(psi) over bar psi > in a spatially flat Friedmann-Lemaitre-Robertson-Walker (FLRW) spacetime. These are basic ingredients in the semiclassical field equations of fermionic matter in curved spacetime interacting with a background scalar field. The ultraviolet subtracting terms of the adiabatic regularization can be naturally interpreted as coming from appropriate counterterms of the background fields. We fix the required covariant counterterms. To test our approach we determine the contribution of the Yukawa interaction to the conformal anomaly in the massless limit and show its consistency with the heat-kernel method using the effective action.
Address [del Rio, Adrian; Ferreiro, Antonio; Navarro-Salas, Jose] Univ Valencia, Fac Fis, Ctr Mixto Univ Valencia CSIC, Dept Fis Teor, E-46100 Valencia, Spain, Email: adrian.rio@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:000401447900006 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 3127
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Author Pla, S.; Newsome, I.M.; Link, R.S.; Anderson, P.R.; Navarro-Salas, J.
Title Pair production due to an electric field in 1+1 dimensions and the validity of the semiclassical approximation Type Journal Article
Year 2021 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 103 Issue 10 Pages (up) 105003 - 23pp
Keywords
Abstract Solutions to the backreaction equation in 1 + 1-dimensional semiclassical electrodynamics are obtained and analyzed when considering a time-varying homogeneous electric field initially generated by a classical electric current, coupled to either a quantized scalar field or a quantized spin-1/2 field. Particle production by way of the Schwinger effect leads to backreaction effects that modulate the electric field strength. Details of the particle production process are investigated along with the transfer of energy between the electric field and the particles. The validity of the semiclassical approximation is also investigated using a criterion previously implemented for chaotic inflation and, in an earlier form, semiclassical gravity. The criterion states that the semiclassical approximation will break down if any linearized gauge-invariant quantity constructed from solutions to the linear response equation, with finite nonsingular data, grows rapidly for some period of time. Approximations to homogeneous solutions of the linear response equation are computed and it is found that the criterion is violated when the maximum value, E-max, obtained by the electric field is of the order of the critical scale for the Schwinger effect, E-max similar to E-crit m(2)/q, where m is the mass of the quantized field and q is its electric charge. For these approximate solutions the criterion appears to be satisfied in the extreme limits qE(max)/m(2) << 1 and qE(max)/m(2) >> 1.
Address [Pla, Silvia; Navarro-Salas, Jose] Univ Valencia, Ctr Mixto Univ Valencia, Fac Fis, CSIC,Dept Fis Teor, E-46100 Valencia, Spain, Email: silvia.pla@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:000655874700008 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4844
Permanent link to this record
 

 
Author Beltran-Palau, P.; Navarro-Salas, J.; Pla, S.
Title Translational anomaly of chiral fermions in two dimensions Type Journal Article
Year 2019 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 99 Issue 10 Pages (up) 105008 - 5pp
Keywords
Abstract It is well known that a quantized two-dimensional Weyl fermion coupled to gravity spoils general covariance and breaks the covariant conservation of the energy-momentum tensor. In this brief article, we point out that the quantum conservation of the momentum can also fail in flat spacetime, provided the Weyl fermion is coupled to a time-varying homogeneous electric field. This signals a quantum anomaly of the space-translation symmetry, which has not been highlighted in the literature so far.
Address [Beltran-Palau, Pau; Navarro-Salas, Jose; Pla, Silvia] Univ Valencia, Dept Fis Teor, Ctr Mixto, CSIC,Fac Fis, E-46100 Valencia, Spain, Email: pau.beltran@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:000468223500013 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 4011
Permanent link to this record