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Author del Rio, A.; Sanchis-Gual, N.; Mewes, V.; Agullo, I.; Font, J.A.; Navarro-Salas, J.
Title Spontaneous Creation of Circularly Polarized Photons in Chiral Astrophysical Systems Type Journal Article
Year 2020 Publication Physical Review Letters Abbreviated Journal Phys. Rev. Lett.
Volume (down) 124 Issue 21 Pages 211301 - 6pp
Keywords
Abstract This work establishes a relation between chiral anomalies in curved spacetimes and the radiative content of the gravitational field. In particular, we show that a flux of circularly polarized gravitational waves triggers the spontaneous creation of photons with net circular polarization from the quantum vacuum. Using waveform catalogs, we identify precessing binary black holes as astrophysical configurations that emit such gravitational radiation and then solve the fully nonlinear Einstein's equations with numerical relativity to evaluate the net effect. The quantum amplitude for a merger is comparable to the Hawking emission rate of the final black hole and small to be directly observed. However, the implications for the inspiral of binary neutron stars could be more prominent, as argued on symmetry grounds.
Address [del Rio, Adrian; Sanchis-Gual, Nicolas] Univ Lisbon, Inst Super Tecn, Ctr Astrofis & Gravitacao CENTRA, Ave Rovisco Pais 1, P-1049001 Lisbon, Portugal
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 0031-9007 ISBN Medium
Area Expedition Conference
Notes WOS:000535679100012 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4407
Permanent link to this record
 
 
Author Agullo, I.; del Rio, A.; Navarro-Salas, J.
Title Electromagnetic Duality Anomaly in Curved Spacetimes Type Journal Article
Year 2017 Publication Physical Review Letters Abbreviated Journal Phys. Rev. Lett.
Volume (down) 118 Issue 11 Pages 111301 - 5pp
Keywords
Abstract The source-free Maxwell action is invariant under electric-magnetic duality rotations in arbitrary spacetimes. This leads to a conserved classical Noether charge. We show that this conservation law is broken at the quantum level in the presence of a background classical gravitational field with a nontrivial Chern-Pontryagin invariant, in parallel with the chiral anomaly for massless Dirac fermions. Among the physical consequences, the net polarization of the quantum electromagnetic field is not conserved.
Address [Agullo, Ivan; del Rio, Adrian] Louisiana State Univ, Dept Phys & Astron, Baton Rouge, LA 70803 USA, Email: agullo@lsu.edu;
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 0031-9007 ISBN Medium
Area Expedition Conference
Notes WOS:000396267100003 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 2964
Permanent link to this record
 
 
Author del Rio, A.; Agullo, I.
Title Chiral fermion anomaly as a memory effect Type Journal Article
Year 2023 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume (down) 108 Issue 10 Pages 105025 - 22pp
Keywords
Abstract We study the nonconservation of the chiral charge of Dirac fields between past and future null infinity due to the Adler-Bell-Jackiw chiral anomaly. In previous investigations [A. del Rio, Phys. Rev. D 104, 065012 (2021)], we found that this charge fails to be conserved if electromagnetic sources in the bulk emit circularly polarized radiation. In this article, we unravel yet another contribution coming from the nonzero, infrared “soft” charges of the external, electromagnetic field. This new contribution can be interpreted as another manifestation of the ordinary memory effect produced by transitions between different infrared sectors of Maxwell theory, but now on test quantum fields rather than on test classical particles. In other words, a flux of electromagnetic waves can leave a memory on quantum fermion states in the form of a permanent, net helicity. We elaborate this idea in both 1 + 1 and 3 + 1 dimensions. We also show that, in sharp contrast, gravitational infrared charges do not contribute to the fermion chiral anomaly.
Address [del Rio, Adrian] Univ Valencia, Dept Fis Teor, CSIC, Dr Moliner 50, Burjassot 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:001121689000004 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5864
Permanent link to this record
 
 
Author Sanchis-Gual, N.; del Rio, A.
Title Precessing binary black holes as engines of electromagnetic helicity Type Journal Article
Year 2023 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume (down) 108 Issue Pages 044052 - 11pp
Keywords
Abstract We show that binary black hole mergers with precessing evolution can potentially excite photons from the quantum vacuum in such a way that total helicity is not preserved in the process. Helicity violation is allowed by quantum fluctuations that spoil the electric-magnetic duality symmetry of the classical Maxwell theory without charges. We show here that precessing binary black hole systems in astrophysics generate a flux of circularly polarized gravitational waves which, in turn, provides the required helical background that triggers this quantum effect. Solving the fully nonlinear Einstein’s equations with numerical relativity we explore the parameter space of binary systems and extract the detailed dependence of the quantum effect with the spins of the two black holes. We also introduce a set of diagrammatic techniques that allows us to predict when a binary black hole merger can or cannot emit circularly polarized gravitational radiation, based on mirror-symmetry considerations. This framework allows to understand and to interpret correctly the numerical results, and to predict the outcomes in potentially interesting astrophysical systems.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 6092
Permanent link to this record
 
 
Author Beltran-Palau, P.; del Rio, A.; Navarro-Salas, J.
Title Quantum corrections to the Schwarzschild metric from vacuum polarization Type Journal Article
Year 2023 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume (down) 107 Issue 8 Pages 085023 - 15pp
Keywords
Abstract We explore static and spherically symmetric solutions of the 4-dimensional semiclassical Einstein's equations using the quantum vacuum polarization of a conformal field as a source. These solutions may be of interest for the study of exotic compact objects (ECOs). The full backreaction problem is addressed by solving the semiclassical Tolman-Oppenheimer-Volkoff (TOV) equations making use of effective equations of state inspired by the trace anomaly and an extra simplifying and reasonable assumption. We combine analytical and numerical techniques to solve the resulting differential equations, both perturbatively and nonperturbatively in h. In all cases the solution is similar to the Schwarzschild metric up p ffiffito the vicinity of the classical horizon r = 2M. However, at r = 2M + epsilon, with epsilon similar to O(root h), we find a coordinate singularity. In the case of matching with a static star, this leads to an upper bound in the compactness, and sets a constraint on the family of stable ECOs. We also study the corrections that the quantum-vacuum polarization induces on the propagation of waves, and discuss the implications. For the pure vacuum case, we can further extend the solution by using appropriate coordinates until we reach another singular point, where this time a null curvature singularity arises and prevents extending beyond. This picture qualitatively agrees with the results obtained in the effective two-dimensional approach, and reinforces the latter as a reasonable method.
Address [Beltran-Palau, Pau; Navarro-Salas, Jose] Univ Valencia, Dept Fis Teor, Burjassot 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:000988649200017 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5543
Permanent link to this record
 
 
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 (down) 103 Issue 10 Pages 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
Permanent link to this record
 
 
Author Agullo, I.; del Rio, A.; Navarro-Salas, J.
Title Classical and quantum aspects of electric-magnetic duality rotations in curved spacetimes Type Journal Article
Year 2018 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume (down) 98 Issue 12 Pages 125001 - 22pp
Keywords
Abstract It is well known that the source-free Maxwell equations are invariant under electric-magnetic duality rotations, F -> F cos theta +*F sin theta. These transformations are indeed a symmetry of the theory in the Noether sense. The associated constant of motion is the difference in the intensity between self-dual and anti-self-dual components of the electromagnetic field or, equivalently, the difference between the right and left circularly polarized components. This conservation law holds even if the electromagnetic field interacts with an arbitrary classical gravitational background. After reexamining these results, we discuss whether this symmetry is maintained when the electromagnetic field is quantized. The answer is in the affirmative in the absence of gravity but not necessarily otherwise. As a consequence, the net polarization of the quantum electromagnetic field fails to be conserved in curved spacetimes. This is a quantum effect, and it can be understood as the generalization of the fermion chiral anomaly to fields of spin one.
Address [Agullo, Ivan] Louisiana State Univ, Dept Phys & Astron, Baton Rouge, LA 70803 USA, Email: agullo@lsu.edu;
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:000451998400004 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3824
Permanent link to this record
 
 
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 (down) 95 Issue 10 Pages 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
Permanent link to this record
 
 
Author del Rio, A.; Navarro-Salas, J.
Title Equivalence of adiabatic and DeWitt-Schwinger renormalization schemes Type Journal Article
Year 2015 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume (down) 91 Issue 6 Pages 064031 - 14pp
Keywords
Abstract We prove that adiabatic regularization and DeWitt-Schwinger point-splitting provide the same result when renormalizing expectation values of the stress-energy tensor for spin-1/2 fields. This generalizes the equivalence found for scalar fields, which is here recovered in a different way. We also argue that the coincidence limit of the DeWitt-Schwinger proper time expansion of the two-point function agrees exactly with the analogous expansion defined by the adiabatic regularization method at any order (for both scalar and spin-1/2 fields). We also illustrate the power of the adiabatic method to compute higher order DeWitt coefficients in Friedmann-Lemaitre-Robertson-Walker Universes.
Address [del Rio, Adrian; Navarro-Salas, Jose] Univ Valencia, Dept Fis Teor, IFIC, Ctr Mixto,CSIC,Fac Fis, 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 1550-7998 ISBN Medium
Area Expedition Conference
Notes WOS:000350966000005 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 2150
Permanent link to this record
 
 
Author del Rio, A.; Navarro-Salas, J.; Torrenti, F.
Title Renormalized stress-energy tensor for spin-1/2 fields in expanding universes Type Journal Article
Year 2014 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume (down) 90 Issue 8 Pages 084017 - 15pp
Keywords
Abstract We provide an explicit expression for the renormalized expectation value of the stress-energy tensor of a spin-1/2 field in a spatially flat Friedmann-Lemaitre-Robertson-Walker universe. Its computation is based on the extension of the adiabatic regularization method to fermion fields introduced recently in the literature. The tensor is given in terms of UV-finite integrals in momentum space, which involve the mode functions that define the quantum state. As illustrative examples of the method efficiency, we see how to compute the renormalized energy density and pressure in two interesting cosmological scenarios: a de Sitter spacetime and a radiation-dominated universe. In the second case, we explicitly show that the late-time renormalized stress-energy tensor behaves as that of classical cold matter. We also check that, if we obtain the adiabatic expansion of the scalar field mode functions with a similar procedure to the one used for fermions, we recover the well-known WKB-type expansion.
Address [del Rio, Adrian; Navarro-Salas, Jose] Univ Valencia, Dept Fis Teor, E-46100 Burjassot, 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 1550-7998 ISBN Medium
Area Expedition Conference
Notes WOS:000343773100003 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 1985
Permanent link to this record