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Author Caerols, H.; Carrasco, R.A.; Asenjo, F.A. openurl 
  Title Using smartphone photographs of the Moon to acquaint students with non-Euclidean geometry Type
  Year 2021 Publication (up) American Journal of Physics Abbreviated Journal Am. J. Phys.  
  Volume Early Access Issue Pages  
  Keywords  
  Abstract Non-Euclidean geometry can be taught to students using astronomical images. By using photographs o the Moon taken with a smartphone through a simple telescope, we were able to introduce these concepts to high-school students and lower-level college students. We teach students how to calculate lengths of mountain ranges or areas of craters on the Moon's surface and introduce ideas of geodesics and spherical triangles. Students can see that accurate measurements cannot be

obtained using at geometry. Instead, by using three{dimensional curved geometry, estimates of lengths and areas can be computed with less than 4% error.
 
  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 0002-9505 ISBN Medium  
  Area Expedition Conference  
  Notes Approved  
  Call Number UAI @ alexi.delcanto @ Serial 1447  
Permanent link to this record
 

 
Author Hojman, S.A.; Asenjo, F.A. doi  openurl
  Title Phenomenological dynamics of COVID-19 pandemic: Meta-analysis for adjustment parameters Type
  Year 2020 Publication (up) 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 Hojman, S.A.; Asenjo, F.A. pdf  doi
openurl 
  Title Can gravitation accelerate neutrinos? Type
  Year 2013 Publication (up) Classical And Quantum Gravity Abbreviated Journal Class. Quantum Gravity  
  Volume 30 Issue 2 Pages 10 pp  
  Keywords  
  Abstract The Lagrangian equations of motion for massive spinning test particles (tops) moving on a gravitational background using general relativity are presented. The paths followed by tops are nongeodesic. An exact solution for the motion of tops on a Schwarzschild background which allows for superluminal propagation of tops is studied. It is shown that the solution becomes relevant for particles with small masses, such as neutrinos. This general result is used to calculate the necessary condition to produce superluminal motion in part of the trajectory of a small mass particle in a weak gravitational field. The condition for superluminal motion establishes a relation between the mass, energy and total angular momentum of the particle.  
  Address [Hojman, Sergio A.] Univ Adolfo Ibanez, Dept Ciencias, Fac Artes Liberales, Fac Ingn & Ciencias, Santiago, Chile, Email: sergio.hojman@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 0264-9381 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000313097300008 Approved  
  Call Number UAI @ eduardo.moreno @ Serial 257  
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Author Zalaquett, N.; Hojman, S.A.; Asenjo, F.A. pdf  doi
openurl 
  Title Spinning massive test particles in cosmological and general static spherically symmetric spacetimes Type
  Year 2014 Publication (up) 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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Author Hojman, S.A.; Asenjo, F.A. pdf  doi
openurl 
  Title Spinning particles coupled to gravity and the validity of the universality of free fall Type
  Year 2017 Publication (up) Classical And Quantum Gravity Abbreviated Journal Class. Quantum Gravity  
  Volume 34 Issue 11 Pages 8 pp  
  Keywords spin-gravity coupling; spinning massive particle; Lagrangian description  
  Abstract Recent experimental work has determined that free falling Rb-87 atoms on Earth, with vertically aligned spins, follow geodesics, thus apparently ruling out spin-gravitation interactions. It is showed that while some spinning matter models coupled to gravitation referenced to in that work seem to be ruled out by the experiment, those same experimental results confirm theoretical results derived from a Lagrangian description of spinning particles coupled to gravity constructed over forty years ago. A proposal to carry out (similar but) different experiments which will help to test the validity of the universality of free fall as opposed to the correctness of the aforementioned Lagrangian theory, is presented.  
  Address [Hojman, Sergio A.] Univ Adolfo Ibanez, Fac Artes Liberales, Dept Ciencias, Santiago, Chile, Email: sergio.hojman@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 0264-9381 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000402399700011 Approved  
  Call Number UAI @ eduardo.moreno @ Serial 735  
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Author Asenjo, F.A.; Hojman, S.A. pdf  doi
openurl 
  Title Do electromagnetic waves always propagate along null geodesics? Type
  Year 2017 Publication (up) Classical And Quantum Gravity Abbreviated Journal Class. Quantum Gravity  
  Volume 34 Issue 20 Pages 12 pp  
  Keywords electromagnetic waves; curved spacetime; non-null geodesics  
  Abstract We find exact solutions to Maxwell equations written in terms of fourvector potentials in non-rotating, as well as in Gdel and Kerr spacetimes. We show that Maxwell equations can be reduced to two uncoupled secondorder differential equations for combinations of the components of the four-vector potential. Exact electromagnetic waves solutions are written on given gravitational field backgrounds where they evolve. We find that in non-rotating spherical symmetric spacetimes, electromagnetic waves travel along null geodesics. However, electromagnetic waves on Gdel and Kerr spacetimes do not exhibit that behavior.  
  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 0264-9381 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000411741800008 Approved  
  Call Number UAI @ eduardo.moreno @ Serial 800  
Permanent link to this record
 

 
Author Asenjo, F.A.; Hojman, S.A. pdf  doi
openurl 
  Title New non-linear modified massless Klein-Gordon equation Type
  Year 2017 Publication (up) 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. pdf  doi
openurl 
  Title Non-geodesic circular motion of massive spinning test bodies around a Schwarzschild field in the Lagrangian theory Type
  Year 2018 Publication (up) 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  
Permanent link to this record
 

 
Author Asenjo, F.A.; Hojman, S.A. pdf  doi
openurl 
  Title Correspondence between dark energy quantum cosmology and Maxwell equations Type
  Year 2019 Publication (up) European Physical Journal C Abbreviated Journal Eur. Phys. J. C  
  Volume 79 Issue 9 Pages 5 pp  
  Keywords  
  Abstract A Friedmann-Robertson-Walker cosmology with dark energy can be modelled using a quintessence field. That system is equivalent to a relativistic particle moving on a two-dimensional conformal spacetime. When the quintessence behaves as a free massless scalar field in a Universe with cosmological constant, the quantized version of that theory can lead to a supersymmetric Majorana quantum cosmology. The purpose of this work is to show that such quantum cosmological model corresponds to the Maxwell equations for electromagnetic waves propagating in a medium with specific values for its relative permittivity and relative permeability. The form of those media parameters are calculated, implying that a Majorana quantum cosmology can be studied in an analogue electromagnetic system.  
  Address [Asenjoa, Felipe A.] Univ Adolfo Ibanez, Fac Ingn & Ciencias, Santiago 7941169, 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:000484523100004 Approved  
  Call Number UAI @ eduardo.moreno @ Serial 1053  
Permanent link to this record
 

 
Author Asenjo, F.A.; Hojman, S.A. doi  openurl
  Title Casimir force induced by electromagnetic wave polarization in Kerr, Godel and Bianchi-I spacetimes Type
  Year 2020 Publication (up) European Physical Journal C Abbreviated Journal Eur. Phys. J. C  
  Volume 80 Issue 11 Pages 7 pp  
  Keywords  
  Abstract Electromagnetic waves propagation on either rotating or anisotropic spacetime backgrounds (such as Kerr and Gödel metrics, or Bianchi�I metric) produce a reduction of the magnitude of Casimir forces between plates. These

curved spacetimes behave as chiral or birefringent materials producing dispersion of electromagnetic waves, in such a way that right� and left�circularly polarized light waves propagate with different phase velocities. Results are explicitly calculated for discussed cases. The difference on the wavevectors of the two polarized electromagnetic waves produces an abatement of a Casimir force which depends on the interaction between the polarization of electromagnetic

waves and the properties of the spacetime.
 
  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 1434-6044 ISBN Medium  
  Area Expedition Conference  
  Notes Approved  
  Call Number UAI @ alexi.delcanto @ Serial 1268  
Permanent link to this record
 

 
Author Asenjo, F.A.; Hojman, S.A. doi  openurl
  Title Accelerating solutions to diffusion equation Type
  Year 2021 Publication (up) European Physical Journal Plus Abbreviated Journal Eur. Phys. J. Plus.  
  Volume 136 Issue 6 Pages 677  
  Keywords NONLINEAR DIFFUSIONSIMILARITY SOLUTIONS  
  Abstract We report accelerating diffusive solutions to the diffusion equation with a constant diffusion tensor. The maximum values of the diffusion density evolve in an accelerating fashion described by Airy functions. We show the diffusive accelerating behavior for one-dimensional systems, as well as for a general three-dimensional case. We also construct a modulated modified form of the diffusion solution that retains the accelerating features.  
  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 2190-5444 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000664659600001 Approved  
  Call Number UAI @ alexi.delcanto @ Serial 1433  
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Author Asenjo, F.A.; Hojman, S.A. pdf  doi
openurl 
  Title Class of Exact Solutions for a Cosmological Model of Unified Gravitational and Quintessence Fields Type
  Year 2017 Publication (up) Foundations Of Physics Abbreviated Journal Found. Phys.  
  Volume 47 Issue 7 Pages 887-896  
  Keywords Quintessence; Exact solution; Unification of geometry and dark matter  
  Abstract A new approach to tackle Einstein equations for an isotropic and homogeneous Friedmann-Robertson-Walker Universe in the presence of a quintessence scalar field is devised. It provides a way to get a simple exact solution to these equations. This solution determines the quintessence potential uniquely and it differs from solutions which have been used to study inflation previously. It relays on a unification of geometry and dark matter implemented through the definition of a functional relation between the scale factor of the Universe and the quintessence field. For a positive curvature Universe, this solution produces perpetual accelerated expansion rate of the Universe, while the Hubble parameter increases abruptly, attains a maximum value and decreases thereafter. The behavior of this cosmological solution is discussed and its main features are displayed. The formalism is extended to include matter and radiation.  
  Address [Asenjo, Felipe A.] Univ Adolfo Ibanez, Fac Ingn & Ciencias, 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 0015-9018 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000404224500003 Approved  
  Call Number UAI @ eduardo.moreno @ Serial 741  
Permanent link to this record
 

 
Author Mahajan, S.M.; Asenjo, F.A. pdf  doi
openurl 
  Title Hot Fluids and Nonlinear Quantum Mechanics Type
  Year 2015 Publication (up) 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  
Permanent link to this record
 

 
Author Asenjo, F.A.; Moya, P.S. doi  openurl
  Title The contribution of magnetic monopoles to the ponderomotive force Type
  Year 2019 Publication (up) Journal Of Physics A-Mathematical And Theoretical Abbreviated Journal J. Phys. A-Math. Theor.  
  Volume 52 Issue 25 Pages 13 pp  
  Keywords plasma waves; magnetic monopoles; ponderomotive force  
  Abstract When magnetic monopoles are assumed to exist in plasma dynamics, the propagation of electromagnetic waves is modified as Maxwell equations acquire a symmetrical structure due to the existence of electric and magnetic charge and current densities. This work presents a theoretical exploration on how far we can push the limits of a plasma theory under the presence of magnetic monopoles. In particular, we study the modification of ponderomotive forces in a plasma composed by electric and magnetic charges. We show that the general ponderomotive force on this plasma depends non-trivially on the magnetic monopoles, through the slow temporal and spatial variations of the electromagnetic field amplitudes. The magnetic charges introduce corrections even if the plasma is unmagnetized. Also, it is shown that the magnetic monopoles also experience a ponderomotive force due to the electrons. This force is in the direction of propagation of the electromagnetic waves.  
  Address [Asenjo, Felipe A.] Univ Adolfo Ibanez, Fac Ingn & Ciencias, Santiago 7941169, 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 1751-8113 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000469448000001 Approved  
  Call Number UAI @ eduardo.moreno @ Serial 1029  
Permanent link to this record
 

 
Author Mahajan, S.M.; Asenjo, F.A. pdf  doi
openurl 
  Title Explicitly covariant dispersion relations and self-induced transparency Type
  Year 2017 Publication (up) Journal Of Plasma Physics Abbreviated Journal J. Plasma Phys.  
  Volume 83 Issue Pages 15 pp  
  Keywords magnetized plasmas; plasma waves  
  Abstract Explicitly covariant dispersion relations for a variety of plasma waves in unmagnetized and magnetized plasmas are derived in a systematic manner from a fully covariant plasma formulation. One needs to invoke relatively little known invariant combinations constructed from the ambient electromagnetic fields and the wave vector to accomplish the program. The implication of this work applied to the self- induced transparency effect is discussed. Some problems arising from the inconsistent use of relativity are pointed out.  
  Address [Mahajan, S. M.] Univ Texas Austin, Inst Fus Studies, Austin, TX 78712 USA, Email: mahajan@mail.utexas.edu;  
  Corporate Author Thesis  
  Publisher Cambridge Univ Press Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0022-3778 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000396123100018 Approved  
  Call Number UAI @ eduardo.moreno @ Serial 713  
Permanent link to this record
 

 
Author Mahajan, S.M.; Asenjo, F.A.; Hazeltine, R.D. pdf  doi
openurl 
  Title Comparison of the electron-spin force and radiation reaction force Type
  Year 2015 Publication (up) Monthly Notices Of The Royal Astronomical Society Abbreviated Journal Mon. Not. Roy. Astron. Soc.  
  Volume 446 Issue 4 Pages 4112-4115  
  Keywords magnetic fields; plasmas; radiation mechanisms: general  
  Abstract It is shown that the forces that originate from the electron-spin interacting with the electromagnetic field can play, along with the Lorentz force, a fundamentally important role in determining the electron motion in a high energy density plasma embedded in strong high-frequency radiation, a situation that pertains to both laser-produced and astrophysical systems. These forces, for instance, dominate the standard radiation reaction force as long as there is a 'sufficiently' strong ambient magnetic field for affecting spin alignment. The inclusion of spin forces in any advanced modelling of electron dynamics pertaining to high energy density systems (for instance in particle-in-cell codes), therefore, is a must.  
  Address [Mahajan, Swadesh M.; Hazeltine, Richard D.] Univ Texas Austin, Inst Fus Studies, Austin, TX 78712 USA, Email: felipe.asenjo@uai.cl  
  Corporate Author Thesis  
  Publisher Oxford Univ Press Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0035-8711 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000350272400066 Approved  
  Call Number UAI @ eduardo.moreno @ Serial 462  
Permanent link to this record
 

 
Author Munoz, V.; Asenjo, F.A.; Dominguez, M.; Lopez, R.A.; Valdivia, J.A.; Vinas, A.; Hada, T. pdf  doi
openurl 
  Title Large-amplitude electromagnetic waves in magnetized relativistic plasmas with temperature Type
  Year 2014 Publication (up) 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  
Permanent link to this record
 

 
Author Asenjo, F.A.; Hojman, S.A.; Moya-Cessa, H.M.; Soto-Eguibar, F. doi  openurl
  Title Propagation of light in linear and quadratic GRIN media: The Bohm potential Type
  Year 2021 Publication (up) 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  
Permanent link to this record
 

 
Author Asenjo, F.A.; Erices, C.; Gomberoff, A.; Hojman, S.A.; Montecinos, A. pdf  doi
openurl 
  Title Differential geometry approach to asymmetric transmission of light Type
  Year 2017 Publication (up) Optics Express Abbreviated Journal Opt. Express  
  Volume 25 Issue 22 Pages 26405-26416  
  Keywords  
  Abstract In the last ten years, the technology of differential geometry, ubiquitous in gravitational physics, has found its place in the field of optics. It has been successfully used in the design of optical metamaterials through a technique now known as “transformation optics.” This method, however, only applies for the particular class of metamaterials known as impedance matched, that is, materials whose electric permittivity is equal to their magnetic permeability. In that case, the material may be described by a spacetime metric. In the present work we will introduce a generalization of the geometric methods of transformation optics to situations in which the material is not impedance matched. In such situations, the material -or more precisely, its constitutive tensor-will not be described by a metric only. We bring in a second tensor, with the local symmetries of the Weyl tensor, the “W-tensor.” In the geometric optics approximation we show how the properties of the W-tensor are related to the asymmetric transmission of the material. We apply this feature to the design of a particularly interesting set of asymmetric materials. These materials are birefringent when light rays approach the material in a given direction, but behave just like vacuum when the rays have the opposite direction with the appropriate polarization (or, in some cases, independently of the polarization). (C) 2017 Optical Society of America  
  Address [Asenjo, Felipe A.; Gomberoff, Andres] Univ Adolfo Ibanez, Fac Ingn & Ciencias, Av Diagonal Torres 2640, Santiago, Chile, Email: andres.gomberoff@uai.cl  
  Corporate Author Thesis  
  Publisher Optical Soc Amer Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1094-4087 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000413995000004 Approved  
  Call Number UAI @ eduardo.moreno @ Serial 798  
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Author Hojman, S.A.; Asenjo, F.A.; Moya-Cessa, H.M.; Soto-Eguibar, F. doi  openurl
  Title Bohm potential is real and its effects are measurable Type
  Year 2021 Publication (up) Optik Abbreviated Journal Optik  
  Volume 232 Issue Pages 166341  
  Keywords Bohm potential; Non-vanishing; Accelerating solutions  
  Abstract We analyze Bohm potential effects both in the realms of Quantum Mechanics and Optics, as well as in the study of other physical phenomena described in terms of classical and quantum wave equations. We approach this subject by using theoretical arguments as well as experimental evidence. We find that the effects produced by Bohm potential are both theoretically responsible for the early success of Quantum Mechanics correctly describing atomic and nuclear phenomena and, more recently, by confirming surprising accelerating behavior of free waves and particles experimentally, for instance.  
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  Series Volume Series Issue Edition  
  ISSN 0030-4026 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000636139700002 Approved  
  Call Number UAI @ alexi.delcanto @ Serial 1366  
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