Records 
Author 
Asenjo, F.A.; Erices, C.; Gomberoff, A.; Hojman, S.A.; Montecinos, A. 
Title 
Differential geometry approach to asymmetric transmission of light 
Type 

Year 
2017 
Publication 
Optics Express 
Abbreviated Journal 
Opt. Express 
Volume 
25 
Issue 
22 
Pages 
2640526416 
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 tensorwill not be described by a metric only. We bring in a second tensor, with the local symmetries of the Weyl tensor, the “Wtensor.” In the geometric optics approximation we show how the properties of the Wtensor 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 
10944087 
ISBN 

Medium 

Area 

Expedition 

Conference 

Notes 
WOS:000413995000004 
Approved 

Call Number 
UAI @ eduardo.moreno @ 
Serial 
798 
Permanent link to this record 



Author 
Mahajan, S.M.; Asenjo, F.A. 
Title 
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 thermalvortical fields. We study the twofluid plasma dynamics plasma expressed in two different sets of variables: the twofluid (2F) description in terms of individual fluid velocities, and the onefluid (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/ElectroVortic) field that is frozenin 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 
1070664x 
ISBN 

Medium 

Area 

Expedition 

Conference 

Notes 
WOS:000426584700020 
Approved 

Call Number 
UAI @ eduardo.moreno @ 
Serial 
1038 
Permanent link to this record 



Author 
Mahajan, S.M.; Asenjo, F.A. 
Title 
A statistical model for relativistic quantum fluids interacting with an intense electromagnetic wave 
Type 

Year 
2016 
Publication 
Physics Of Plasmas 
Abbreviated Journal 
Phys. Plasmas 
Volume 
23 
Issue 
5 
Pages 
12 pp 
Keywords 

Abstract 
A statistical model for relativistic quantum fluids interacting with an arbitrary amplitude circularly polarized electromagnetic wave is developed in two steps. First, the energy spectrum and the wave function for a quantum particle (Klein Gordon and Dirac) embedded in the electromagnetic wave are calculated by solving the appropriate eigenvalue problem. The energy spectrum is anisotropic in the momentum K and reflects the electromagnetic field through the renormalization of the rest mass m to M = root m(2) + q(2)Q(2). Based on this energy spectrum of this quantum particle plus field combination (QPF), a statistical mechanics model of the quantum fluid made up of these weakly interacting QPF is developed. Preliminary investigations of the formalism yield highly interesting resultsa new scale for temperature, and fundamental modification of the dispersion relation of the electromagnetic wave. It is expected that this formulation could, inter alia, uniquely advance our understanding of laboratory as well as astrophysical systems where one encounters arbitrarily large electromagnetic fields. (C) 2016 AIP Publishing LLC. 
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 
1070664x 
ISBN 

Medium 

Area 

Expedition 

Conference 

Notes 
WOS:000378427900152 
Approved 

Call Number 
UAI @ eduardo.moreno @ 
Serial 
638 
Permanent link to this record 



Author 
Asenjo, F.A.; Comisso, L.; Mahajan, S.M. 
Title 
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 
1070664x 
ISBN 

Medium 

Area 

Expedition 

Conference 

Notes 
WOS:000367460400019 
Approved 

Call Number 
UAI @ eduardo.moreno @ 
Serial 
573 
Permanent link to this record 



Author 
Munoz, V.; Asenjo, F.A.; Dominguez, M.; Lopez, R.A.; Valdivia, J.A.; Vinas, A.; Hada, T. 
Title 
Largeamplitude 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 
217236 
Keywords 

Abstract 
Propagation of largeamplitude 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, laserplasma interaction, and extragalactic jets. For largeamplitude 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 1D 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 
10235809 
ISBN 

Medium 

Area 

Expedition 

Conference 

Notes 
WOS:000332337700017 
Approved 

Call Number 
UAI @ eduardo.moreno @ 
Serial 
360 
Permanent link to this record 



Author 
Rubio, C.A.; Asenjo, F.A.; Hojman, S.A. 
Title 
Quantum Cosmologies Under Geometrical Unification of Gravity and Dark Energy 
Type 

Year 
2019 
Publication 
SymmetryBasel 
Abbreviated Journal 
Symmetry 
Volume 
11 
Issue 
7 
Pages 

Keywords 

Abstract 
A FriedmannRobertsonWalker Universe was studied with a dark energy component represented by a quintessence field. The Lagrangian for this system, hereafter called the FriedmannRobertsonWalkerquintessence (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 twodimensional, 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 KleinGordon 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 
20738994 
ISBN 

Medium 

Area 

Expedition 

Conference 

Notes 
WOS:000481979000025 
Approved 

Call Number 
UAI @ eduardo.moreno @ 
Serial 
1048 
Permanent link to this record 