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Author Mahajan, S.M.; Asenjo, F.A.
Title (up) General connected and reconnected fields in plasmas Type
Year 2018 Publication Physics Of Plasmas Abbreviated Journal Phys. Plasmas
Volume 25 Issue 2 Pages 7 pp
Keywords
Abstract For plasma dynamics, more encompassing than the magnetohydrodynamical (MHD) approximation, the foundational concepts of “magnetic reconnection” may require deep revisions because, in the larger dynamics, magnetic field is no longer connected to the fluid lines; it is replaced by more general fields (one for each plasma specie) that are weighted combination of the electromagnetic and the thermal-vortical fields. We study the two-fluid plasma dynamics plasma expressed in two different sets of variables: the two-fluid (2F) description in terms of individual fluid velocities, and the one-fluid (1F) variables comprising the plasma bulk motion and plasma current. In the 2F description, a Connection Theorem is readily established; we show that, for each specie, there exists a Generalized (Magnetofluid/Electro-Vortic) field that is frozen-in the fluid and consequently remains, forever, connected to the flow. This field is an expression of the unification of the electromagnetic, and fluid forces (kinematic and thermal) for each specie. Since the magnetic field, by itself, is not connected in the first place, its reconnection is never forbidden and does not require any external agency (like resistivity). In fact, a magnetic field reconnection (local destruction) must be interpreted simply as a consequence of the preservation of the dynamical structure of the unified field. In the 1F plasma description, however, it is shown that there is no exact physically meaningful Connection Theorem; a general and exact field does not exist, which remains connected to the bulk plasma flow. It is also shown that the helicity conservation and the existence of a Connected field follow from the same dynamical structure; the dynamics must be expressible as an ideal Ohm's law with a physical velocity. This new perspective, emerging from the analysis of the post MHD physics, must force us to reexamine the meaning as well as our understanding of magnetic reconnection. Published by AIP Publishing.
Address [Mahajan, Swadesh M.] Univ Texas Austin, Inst Fus Studies, Austin, TX 78712 USA, Email: mahajan@mail.utexas.edu;
Corporate Author Thesis
Publisher Amer Inst Physics Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1070-664x ISBN Medium
Area Expedition Conference
Notes WOS:000426584700020 Approved
Call Number UAI @ eduardo.moreno @ Serial 1038
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Author Comisso, L.; Asenjo, F.A.
Title (up) Generalized magnetofluid connections in a curved spacetime Type
Year 2020 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 102 Issue 2 Pages 8 pp
Keywords
Abstract The ideal magnetohydrodynamic theorem on the conservation of the magnetic connections between plasma elements is extended to nonideal relativistic plasmas in curved spacetime. The existence of generalized magnetofluid connections that are preserved by the plasma dynamics is formalized by means of a covariant connection equation that includes different nonideal effects. These generalized connections are constituted by 2-dimensional hypersurfaces, which are linked to an antisymmetric tensor field that unifies the electromagnetic and fluid fields. They can be interpreted in terms of generalized magnetofluid vorticity field lines by considering a 3 + 1 foliation of spacetime and a time resetting projection that compensates for the loss of simultaneity between spatially separated events. The worldshects of the generalized magnetofluid vorticity field lines play a fundamental role in the plasma dynamics by prohibiting evolutions that do not preserve the magnetofluid connectivity.
Address [Comisso, Luca] Columbia Univ, Dept Astron, New York, NY 10027 USA, Email: luca.comisso@columbia.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:000552579500002 Approved
Call Number UAI @ eduardo.moreno @ Serial 1212
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Author Asenjo, F.A.; Comisso, L.; Mahajan, S.M.
Title (up) Generalized magnetofluid connections in pair plasmas Type
Year 2015 Publication Physics Of Plasmas Abbreviated Journal Phys. Plasmas
Volume 22 Issue 12 Pages 4 pp
Keywords
Abstract We extend the magnetic connection theorem of ideal magnetohydrodynamics to nonideal relativistic pair plasmas. Adopting a generalized Ohm's law, we prove the existence of generalized magnetofluid connections that are preserved by the plasma dynamics. We show that these connections are related to a general antisymmetric tensor that unifies the electromagnetic and fluid fields. The generalized magnetofluid connections set important constraints on the plasma dynamics by forbidding transitions between configurations with different magnetofluid connectivity. An approximated solution is explicitly shown where the corrections due to current inertial effects are found. (C) 2015 AIP Publishing LLC.
Address [Asenjo, Felipe A.] Univ Adolfo Ibanez, Fac Ingn & Ciencias, Santiago 7941169, Chile, Email: felipe.asenjo@uai.cl;
Corporate Author Thesis
Publisher Amer Inst Physics Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1070-664x ISBN Medium
Area Expedition Conference
Notes WOS:000367460400019 Approved
Call Number UAI @ eduardo.moreno @ Serial 573
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Author Asenjo, F.A.; Comisso, L.
Title (up) Generalized Magnetofluid Connections in Relativistic Magnetohydrodynamics Type
Year 2015 Publication Physical Review Letters Abbreviated Journal Phys. Rev. Lett.
Volume 114 Issue 11 Pages 5 pp
Keywords
Abstract The concept of magnetic connections is extended to nonideal relativistic magnetohydrodynamical plasmas. Adopting a general set of equations for relativistic magnetohydrodynamics including thermal-inertial, thermal electromotive, Hall, and current-inertia effects, we derive a new covariant connection equation showing the existence of generalized magnetofluid connections that are preserved during the dissipationless plasma dynamics. These connections are intimately linked to a general antisymmetric tensor that unifies the electromagnetic and fluid fields, allowing the extension of the magnetic connection notion to a much broader concept.
Address [Asenjo, Felipe A.] Univ Adolfo Ibanez, Fac Ingn & Ciencias, Santiago 7941169, Chile, Email: felipe.asenjo@uai.cl;
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:000351507400011 Approved
Call Number UAI @ eduardo.moreno @ Serial 478
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Author Asenjo, F.A.; Comisso, L.
Title (up) Gravitational electromotive force in magnetic reconnection around Schwarzschild black holes Type
Year 2019 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 99 Issue 6 Pages 7 pp
Keywords
Abstract We analytically explore the effects of the gravitational electromotive force on magnetic reconnection around Schwarzschild black holes through a generalized general-relativistic magnetohydrodynamic model that retains two-fluid effects. It is shown that the gravitational electromotive force can couple to collisionless two-fluid effects and drive magnetic reconnection. This is allowed by the departure from quasineutrality in curved spacetime, which is explicitly manifested as the emergence of an effective resistivity in Ohm's law. The departure from quasineutrality is owed to different gravitational pulls experienced by separate parts of the current layer. This produces an enhancement of the reconnecion rate due to purely gravitational effects.
Address [Asenjo, Felipe A.] Univ Adolfo Ibanez, Fac Ingn & Ciencias, Santiago 7941169, Chile, Email: felipe.asenjo@uai.cl;
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:000462917900001 Approved
Call Number UAI @ eduardo.moreno @ Serial 993
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Author Mahajan, S.M.; Asenjo, F.A.
Title (up) Hot Fluids and Nonlinear Quantum Mechanics Type
Year 2015 Publication International Journal Of Theoretical Physics Abbreviated Journal Int. J. Theor. Phys.
Volume 54 Issue 5 Pages 1435-1449
Keywords Nonlinear quantum mechanics; Fluids; Temperature; High energy density physics
Abstract A hot relativistic fluid is viewed as a collection of quantum objects that represent interacting elementary particles. We present a conceptual framework for deriving nonlinear equations of motion obeyed by these hypothesized objects. A uniform phenomenological prescription, to affect the quantum transition from a corresponding classical system, is invoked to derive the nonlinear Schrodinger, Klein-Gordon, and Pauli-Schrodinger and Feynman-GellMaan equations. It is expected that the emergent hypothetical nonlinear quantum mechanics would advance, in a fundamental way, both the conceptual understanding and computational abilities, particularly, in the field of extremely high energy-density physics.
Address [Mahajan, Swadesh M.] Univ Texas Austin, Inst Fus Studies, Austin, TX 78712 USA, Email: mahajan@mail.utexas.edu;
Corporate Author Thesis
Publisher Springer/Plenum Publishers Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0020-7748 ISBN Medium
Area Expedition Conference
Notes WOS:000352858600004 Approved
Call Number UAI @ eduardo.moreno @ Serial 485
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Author Munoz, V.; Asenjo, F.A.; Dominguez, M.; Lopez, R.A.; Valdivia, J.A.; Vinas, A.; Hada, T.
Title (up) Large-amplitude electromagnetic waves in magnetized relativistic plasmas with temperature Type
Year 2014 Publication Nonlinear Processes In Geophysics Abbreviated Journal Nonlinear Process Geophys.
Volume 21 Issue 1 Pages 217-236
Keywords
Abstract Propagation of large-amplitude waves in plasmas is subject to several sources of nonlinearity due to relativistic effects, either when particle quiver velocities in the wave field are large, or when thermal velocities are large due to relativistic temperatures. Wave propagation in these conditions has been studied for decades, due to its interest in several contexts such as pulsar emission models, laser-plasma interaction, and extragalactic jets. For large-amplitude circularly polarized waves propagating along a constant magnetic field, an exact solution of the fluid equations can be found for relativistic temperatures. Relativistic thermal effects produce: (a) a decrease in the effective plasma frequency (thus, waves in the electromagnetic branch can propagate for lower frequencies than in the cold case); and (b) a decrease in the upper frequency cutoff for the Alfven branch (thus, Alfven waves are confined to a frequency range that is narrower than in the cold case). It is also found that the Alfven speed decreases with temperature, being zero for infinite temperature. We have also studied the same system, but based on the relativistic Vlasov equation, to include thermal effects along the direction of propagation. It turns out that kinetic and fluid results are qualitatively consistent, with several quantitative differences. Regarding the electromagnetic branch, the effective plasma frequency is always larger in the kinetic model. Thus, kinetic effects reduce the transparency of the plasma. As to the Alfven branch, there is a critical, nonzero value of the temperature at which the Alfven speed is zero. For temperatures above this critical value, the Alfven branch is suppressed; however, if the background magnetic field increases, then Alfven waves can propagate for larger temperatures. There are at least two ways in which the above results can be improved. First, nonlinear decays of the electromagnetic wave have been neglected; second, the kinetic treatment considers thermal effects only along the direction of propagation. We have approached the first subject by studying the parametric decays of the exact wave solution found in the context of fluid theory. The dispersion relation of the decays has been solved, showing several resonant and nonresonant instabilities whose dependence on the wave amplitude and plasma temperature has been studied systematically. Regarding the second subject, we are currently performing numerical 1-D particle in cell simulations, a work that is still in progress, although preliminary results are consistent with the analytical ones.
Address [Munoz, V.; Dominguez, M.; Lopez, R. A.; Valdivia, J. A.] Univ Chile, Fac Ciencias, Dept Fis, Santiago, Chile, Email: vmunoz@fisica.ciencias.uchile.cl
Corporate Author Thesis
Publisher Copernicus Gesellschaft Mbh Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1023-5809 ISBN Medium
Area Expedition Conference
Notes WOS:000332337700017 Approved
Call Number UAI @ eduardo.moreno @ Serial 360
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Author Asenjo, F.A.; Comisso, L.
Title (up) Magnetic connections in curved spacetime Type
Year 2017 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 96 Issue 12 Pages 7 pp
Keywords
Abstract The ideal magnetohydrodynamic theorem on the conservation of the magnetic connections between plasma elements is generalized to relativistic plasmas in curved spacetime. The connections between plasma elements, which are established by a covariant connection equation, display a particularly complex structure in curved spacetime. Nevertheless, it is shown that these connections can be interpreted in terms of magnetic field lines alone by adopting a 3 + 1 foliation of spacetime.
Address [Asenjo, Felipe A.] Univ Adolfo Ibanez, Fac Ingn & Ciencias, Santiago 7941169, Chile, Email: felipe.asenjo@uai.cl;
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:000417759400002 Approved
Call Number UAI @ eduardo.moreno @ Serial 785
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Author Qadir, A.; Asenjo, F.A.; Mahajan, S.M.
Title (up) Magnetic field seed generation in plasmas around charged and rotating black holes Type
Year 2014 Publication Physica Scripta Abbreviated Journal Phys. Scr.
Volume 89 Issue 8 Pages 7 pp
Keywords seed magnetic field; general relativistic drive; Kerr metric
Abstract Previous work by the authors introduced the possibility of generating seed magnetic fields by spacetime curvature and applied it in the vicinity of a Schwarzschild black hole. It was pointed out that it would be worthwhile to consider the effect in other background geometries and particularly in the vicinity of a rotating black hole, which is generically to be expected, astrophysically. In this paper that suggestion is followed up and we calculate generated magnetic field seed due to Reissner-Nordstrom and Kerr spacetimes. The conditions for the drive for the seed of a magnetic field is obtained for charged black holes, finding that in the horizon the drive vanishes. Also, the psi N-force produced by the Kerr black hole is obtained and its relation with the magnetic field seed is discussed, producing a more effective drive.
Address [Qadir, Asghar] Natl Univ Sci & Technol, Ctr Adv Math & Phys, Islamabad 4400, Pakistan, Email: aqadirmath@yahoo.com
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 0031-8949 ISBN Medium
Area Expedition Conference
Notes WOS:000343295000004 Approved
Call Number UAI @ eduardo.moreno @ Serial 469
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Author Asenjo, F.A.; Hojman, S.A.
Title (up) New non-linear modified massless Klein-Gordon equation Type
Year 2017 Publication European Physical Journal C Abbreviated Journal Eur. Phys. J. C
Volume 77 Issue 11 Pages 5 pp
Keywords
Abstract The massless Klein-Gordon equation on arbitrary curved backgrounds allows for solutions which develop “tails” inside the light cone and, therefore, do not strictly follow null geodesics as discovered by DeWitt and Brehme almost 60 years ago. A modification of the massless Klein-Gordon equation is presented, which always exhibits null geodesic propagation of waves on arbitrary curved space-times. This new equation is derived from a Lagrangian which exhibits current-current interaction. Its non-linearity is due to a self-coupling term which is related to the quantum mechanical Bohm potential.
Address [Asenjo, Felipe A.; Hojman, Sergio A.] Univ Adolfo Ibanez, UAI Phys Ctr, Santiago, Chile, Email: felipe.asenjo@uai.cl;
Corporate Author Thesis
Publisher Springer Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1434-6044 ISBN Medium
Area Expedition Conference
Notes WOS:000414439100003 Approved
Call Number UAI @ eduardo.moreno @ Serial 791
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Author Hojman, S.A.; Asenjo, F.A.
Title (up) Non-geodesic circular motion of massive spinning test bodies around a Schwarzschild field in the Lagrangian theory Type
Year 2018 Publication European Physical Journal C Abbreviated Journal Eur. Phys. J. C
Volume 78 Issue 10 Pages 7 pp
Keywords
Abstract Recent interest on studying possible violations of the Equivalence Principle has led to the development of space satellite missions testing it for bodies moving on circular orbits around Earth. This experiment establishes that the validity of the equivalence principle is independent of the composition of bodies. However, the internal degrees of freedom of the bodies (such as spin) were not taken into account. In this work, it is shown exactly that the circular orbit motion of test bodies does present a departure from geodesic motion when spin effects are not negligible. Using a Lagrangian theory for spinning massive bodies, an exact solution for their circular motion is found showing that the non-geodesic behavior manifests through different tangential velocities of the test bodies, depending on the orientation of its spin with respect to the total angular momentum of the satellite. Besides, for circular orbits, spinning test bodies present no tangential acceleration. We estimate the difference of the two possible tangential velocities for the case of circular motion of spinning test bodies orbiting Earth.
Address [Hojman, Sergio A.] Univ Adolfo Ibanez, Fac Artes Liberales, Dept Ciencias, Santiago, Chile, Email: sergio.hojman@uai.cl;
Corporate Author Thesis
Publisher Springer Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1434-6044 ISBN Medium
Area Expedition Conference
Notes WOS:000447801100002 Approved
Call Number UAI @ eduardo.moreno @ Serial 921
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Author Hojman, S.A.; Asenjo, F.A.
Title (up) Phenomenological dynamics of COVID-19 pandemic: Meta-analysis for adjustment parameters Type
Year 2020 Publication Chaos Abbreviated Journal Chaos
Volume 30 Issue 10 Pages 12 pp
Keywords
Abstract We present a phenomenological procedure of dealing with the COVID-19 (coronavirus disease 2019) data provided by government health agencies of 11 different countries. Usually, the exact or approximate solutions of susceptible-infected-recovered (or other) model(s) are obtained fitting the data by adjusting the time-independent parameters that are included in those models. Instead of that, in this work, we introduce dynamical parameters whose time-dependence may be phenomenologically obtained by adequately extrapolating a chosen subset of the daily provided data. This phenomenological approach works extremely well to properly adjust the number of infected (and removed) individuals in time for the countries we consider. Besides, it can handle the sub-epidemic events that some countries may experience. In this way, we obtain the evolution of the pandemic without using any a priori model based on differential equations.
Address [Hojman, Sergio A.] Univ Adolfo Ibanez, Fac Artes Lib, Dept Ciencias, Santiago 7491169, Chile, Email: sergio.hojman@uai.cl;
Corporate Author Thesis
Publisher Amer Inst Physics Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1054-1500 ISBN Medium
Area Expedition Conference
Notes WOS:000585761000001 Approved
Call Number UAI @ alexi.delcanto @ Serial 1257
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Author Asenjo, F.A.; Hojman, S.A.; Moya-Cessa, H.M.; Soto-Eguibar, F.
Title (up) Propagation of light in linear and quadratic GRIN media: The Bohm potential Type
Year 2021 Publication Optics Communications Abbreviated Journal Opt. Commun.
Volume 490 Issue Pages 126947
Keywords
Abstract It is shown that field propagation in linear and quadratic gradient-index (GRIN) media obeys the same rules of free propagation in the sense that a field propagating in free space has a (mathematical) form that may be exported to those particular GRIN media. The Bohm potential is introduced in order to explain the reason of such behavior: it changes the dynamics by modifying the original potential . The concrete cases of two different initials conditions for each potential are analyzed.
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 0030-4018 ISBN Medium
Area Expedition Conference
Notes WOS:000664742700011 Approved
Call Number UAI @ alexi.delcanto @ Serial 1424
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Author Rubio, C.A.; Asenjo, F.A.; Hojman, S.A.
Title (up) Quantum Cosmologies Under Geometrical Unification of Gravity and Dark Energy Type
Year 2019 Publication Symmetry-Basel Abbreviated Journal Symmetry
Volume 11 Issue 7 Pages
Keywords
Abstract A Friedmann-Robertson-Walker Universe was studied with a dark energy component represented by a quintessence field. The Lagrangian for this system, hereafter called the Friedmann-Robertson-Walker-quintessence (FRWq) system, was presented. It was shown that the classical Lagrangian reproduces the usual two (second order) dynamical equations for the radius of the Universe and for the quintessence scalar field, as well as a (first order) constraint equation. Our approach naturally unified gravity and dark energy, as it was obtained that the Lagrangian and the equations of motion are those of a relativistic particle moving on a two-dimensional, conformally flat spacetime. The conformal metric factor was related to the dark energy scalar field potential. We proceeded to quantize the system in three different schemes. First, we assumed the Universe was a spinless particle (as it is common in literature), obtaining a quantum theory for a Universe described by the Klein-Gordon equation. Second, we pushed the quantization scheme further, assuming the Universe as a Dirac particle, and therefore constructing its corresponding Dirac and Majorana theories. With the different theories, we calculated the expected values for the scale factor of the Universe. They depend on the type of quantization scheme used. The differences between the Dirac and Majorana schemes are highlighted here. The implications of the different quantization procedures are discussed. Finally, the possible consequences for a multiverse theory of the Dirac and Majorana quantized Universe are briefly considered.
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 2073-8994 ISBN Medium
Area Expedition Conference
Notes WOS:000481979000025 Approved
Call Number UAI @ eduardo.moreno @ Serial 1048
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Author Hojmann, S.A.; Asenjo, F.A.
Title (up) Quantum particles that behave as free classical particles Type
Year 2020 Publication PHYSICAL REVIEW A Abbreviated Journal Phys. Rev. A
Volume 102 Issue 5 Pages 052211
Keywords Wave; Generation
Abstract The existence of nonvanishing Bohm potentials, in the Madelung-Bohm version of the Schrödinger equation, allows for the construction of particular solutions for states of quantum particles interacting with nontrivial external potentials that propagate as free classical particles. Such solutions are constructed with phases which satisfy the classical Hamilton-Jacobi for free particles and whose probability densities propagate with constant velocity, as free classical particles do.
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 2469-9926 ISBN Medium
Area Expedition Conference
Notes Approved
Call Number UAI @ alexi.delcanto @ Serial 1269
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Author Ekman, R.; Asenjo, F.A.; Zamanian, J.
Title (up) Relativistic kinetic equation for spin-1/2 particles in the long-scale-length approximation Type
Year 2017 Publication Physical Review E Abbreviated Journal Phys. Rev. E
Volume 96 Issue 2 Pages 8 pp
Keywords
Abstract In this paper, we derive a fully relativistic kinetic theory for spin-1/2 particles and its coupling to Maxwell's equations, valid in the long-scale-length limit, where the fields vary on a scale much longer than the localization of the particles; we work to first order in (h) over bar. Our starting point is a Foldy-Wouthuysen (FW) transformation, applicable to this regime, of the Dirac Hamiltonian. We derive the corresponding evolution equation for the Wigner quasidistribution in an external electromagnetic field. Using a Lagrangian method we find expressions for the charge and current densities, expressed as free and bound parts. It is furthermore found that the velocity is nontrivially related to the momentum variable, with the difference depending on the spin and the external electromagnetic fields. This fact that has previously been discussed as “hidden momentum” and is due to that the FW transformation maps pointlike particles to particle clouds for which the prescription of minimal coupling is incorrect, as they have multipole moments. We express energy and momentum conservation for the system of particles and the electromagnetic field, and discuss our results in the context of the Abraham-Minkowski dilemma.
Address [Ekman, R.; Zamanian, J.] Umea Univ, Dept Phys, SE-90187 Umea, Sweden
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 2470-0045 ISBN Medium
Area Expedition Conference
Notes WOS:000408118100012 Approved
Call Number UAI @ eduardo.moreno @ Serial 759
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Author Asenjo, F.A.; Comisso, L.
Title (up) Relativistic Magnetic Reconnection in Kerr Spacetime Type
Year 2017 Publication Physical Review Letters Abbreviated Journal Phys. Rev. Lett.
Volume 118 Issue 5 Pages 5 pp
Keywords
Abstract The magnetic reconnection process is analyzed for relativistic magnetohydrodynamical plasmas around rotating black holes. A simple generalization of the Sweet-Parker model is used as a first approximation to the problem. The reconnection rate, as well as other important properties of the reconnection layer, has been calculated taking into account the effect of spacetime curvature. Azimuthal and radial current sheet configurations in the equatorial plane of the black hole have been studied, and the case of small black hole rotation rate has been analyzed. For the azimuthal configuration, it is found that the black hole rotation decreases the reconnection rate. On the other hand, in the radial configuration, it is the gravitational force created by the black hole mass that decreases the reconnection rate. These results establish a fundamental interaction between gravity and magnetic reconnection in astrophysical contexts.
Address [Asenjo, Felipe A.] Univ Adolfo Ibanez, Fac Ingn & Ciencias, Santiago 7941169, Chile, Email: felipe.asenjo@uai.cl;
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:000396415100005 Approved
Call Number UAI @ eduardo.moreno @ Serial 702
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Author Asenjo, F.A.; Mahajan, S.M.
Title (up) Relativistic quantum vorticity of the quadratic form of the Dirac equation Type
Year 2015 Publication Physica Scripta Abbreviated Journal Phys. Scr.
Volume 90 Issue 1 Pages 4 pp
Keywords relativistic quantum mechanics; hydrodynamical version; Feynman-GellMann equation
Abstract We explore the fluid version of the quadratic form of the Dirac equation, sometimes called the Feynman-Gell-Mann equation. The dynamics of the quantum spinor field is represented by equations of motion for the fluid density, the velocity field, and the spin field. In analogy with classical relativistic and non-relativistic quantum theories, the fully relativistic fluid formulation of this equation allows a vortex dynamics. The vortical form is described by a total tensor field that is the weighted combination of the inertial, electromagnetic and quantum forces. The dynamics contrives the quadratic form of the Dirac equation as a total vorticity free system.
Address [Asenjo, Felipe A.] Univ Adolfo Ibanez, Fac Ingn & Ciencias, Santiago, Chile, Email: felipe.asenjo@uai.cl
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 0031-8949 ISBN Medium
Area Expedition Conference
Notes WOS:000349301500001 Approved
Call Number UAI @ eduardo.moreno @ Serial 458
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Author Asenjo, F.A.; Mahajan, S.M.
Title (up) Resonant interaction between dispersive gravitational waves and scalar massive particles Type
Year 2020 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 101 Issue 6 Pages 4 pp
Keywords
Abstract The Klein-Gordon equation is solved in the curved background spacetime created by a dispersive gravitational wave. Unlike solutions of perturbed Einstein equations in vacuum, dispersive gravitational waves do not travel exactly at the speed of light. As a consequence, the gravitational wave can resonantly exchange energy with scalar massive particles. Some details of the resonant interaction are displayed in a calculation demonstrating how relativistic particles (modeled by the Klein-Gordon equation), feeding on such gravitational waves, may be driven to extreme energies.
Address [Asenjo, Felipe A.] Univ Adolfo Ibanez, Fac Ingn & Ciencias, Santiago 7941169, Chile, Email: felipe.asenjo@uai.cl;
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:000518819200001 Approved
Call Number UAI @ eduardo.moreno @ Serial 1160
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Author Zalaquett, N.; Hojman, S.A.; Asenjo, F.A.
Title (up) Spinning massive test particles in cosmological and general static spherically symmetric spacetimes Type
Year 2014 Publication Classical And Quantum Gravity Abbreviated Journal Class. Quantum Gravity
Volume 31 Issue 8 Pages 21 pp
Keywords exact solution; conformally flat spacetimes; spinning massive particle; cosmological spacetimes
Abstract A Lagrangian formalism is used to study the motion of a spinning massive particle in Friedmann-Robertson-Walker and Godel spacetimes, as well as in a general Schwarzschild-like spacetime and in static spherically symmetric conformally flat spacetimes. Exact solutions for the motion of the particle and general exact expressions for the momenta and velocities are displayed for different cases. In particular, the solution for the motion in spherically symmetric metrics is presented in the equatorial plane. The exact solutions are found using constants of motion of the particle, namely its mass, its spin, its angular momentum, and a fourth constant, which is its energy when the metric is time-independent, and a different constant otherwise. These constants are associated to Killing vectors. In the case of the motion on the Friedmann-Robertson-Walker metric, a new constant of motion is found. This is the fourth constant which generalizes previously known results obtained for spinless particles. In the case of general Schwarzschild-like spacetimes, our results allow for the exploration of the case of the Reissner-Nordstrom-(Anti) de Sitter metric. Finally, for the case of the conformally flat spacetimes, the solution is explicitly evaluated for different metric tensors associated to a universe filled with static perfect fluids and electromagnetic radiation. For some combination of the values of the constants of motion the particle trajectories may exhibit spacelike velocity vectors in portions of the trajectories.
Address [Zalaquett, Nicolas] Pontificia Univ Catolica Chile, Fac Fis, Santiago 22, Chile, Email: nzalaque@puc.cl;
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:000334418900012 Approved
Call Number UAI @ eduardo.moreno @ Serial 373
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