Semi-classical description of Rydberg atoms in strong, single-cycle electromagnetic pulses
International Nuclear Information System (INIS)
Jensen, R.V.; Sanders, M.M.
1993-01-01
Recent experimental measurements of the excitation and ionization of Rydberg atoms by single-cycle, electromagnetic pulses have revealed a variety of novel features. Because many quantum states are strongly coupled by the broadband radiation in the short pulse, the traditional methods of quantum mechanics are inadequate to account for the experimental results. We have therefore developed a semi-classical description of the interaction of both hydrogenic and non-hydrogenic atoms with single-cycle pulses of intense, electromagnetic radiation which is based on the strong correspondence theory of Percival and Richards. This theory, which was originally introduced for the description of strong atomic collisions, accounts for some of the surprising features of the experimental measurements and provides new predictions for future experimental studies
Classical electromagnetic radiation
Heald, Mark A
2012-01-01
Newly corrected, this highly acclaimed text is suitable for advanced physics courses. The author presents a very accessible macroscopic view of classical electromagnetics that emphasizes integrating electromagnetic theory with physical optics. The survey follows the historical development of physics, culminating in the use of four-vector relativity to fully integrate electricity with magnetism.
New perspectives on classical electromagnetism
Cote, Paul J.
2009-01-01
The fallacies associated with the gauge concept in electromagnetism are illustrated. A clearer and more valid formulation of the basics of classical electromagnetism is provided by recognizing existing physical constraints as well as the physical reality of the vector potential.
The classical electromagnetic field
Eyges, Leonard
2010-01-01
This excellent text covers a year's course in advanced theoretical electromagnetism, first introducing theory, then its application. Topics include vectors D and H inside matter, conservation laws for energy, momentum, invariance, form invariance, covariance in special relativity, and more.
Solved problems in classical electromagnetism
Franklin, Jerrold
2018-01-01
This original Dover publication is the companion to a new edition of the author's Classical Electromagnetism: Second Edition. The latter volume will feature only basic answers; this book will contain some problems from the reissue as well as many other new ones. All feature complete, worked-out solutions and form a valuable source of problem-solving material for students.
Classical electromagnetism in a nutshell
Garg, Anupam
2012-01-01
This graduate-level physics textbook provides a comprehensive treatment of the basic principles and phenomena of classical electromagnetism. While many electromagnetism texts use the subject to teach mathematical methods of physics, here the emphasis is on the physical ideas themselves. Anupam Garg distinguishes between electromagnetism in vacuum and that in material media, stressing that the core physical questions are different for each. In vacuum, the focus is on the fundamental content of electromagnetic laws, symmetries, conservation laws, and the implications for phenomena such as radiation and light. In material media, the focus is on understanding the response of the media to imposed fields, the attendant constitutive relations, and the phenomena encountered in different types of media such as dielectrics, ferromagnets, and conductors. The text includes applications to many topical subjects, such as magnetic levitation, plasmas, laser beams, and synchrotrons.
Nonlinear classical theory of electromagnetism
International Nuclear Information System (INIS)
Pisello, D.
1977-01-01
A topological theory of electric charge is given. Einstein's criteria for the completion of classical electromagnetic theory are summarized and their relation to quantum theory and the principle of complementarity is indicated. The inhibiting effect that this principle has had on the development of physical thought is discussed. Developments in the theory of functions on nonlinear spaces provide the conceptual framework required for the completion of electromagnetism. The theory is based on an underlying field which is a continuous mapping of space-time into points on the two-sphere. (author)
Classical mechanics and electromagnetism in accelerator physics
Stupakov, Gennady
2018-01-01
This self-contained textbook with exercises discusses a broad range of selected topics from classical mechanics and electromagnetic theory that inform key issues related to modern accelerators. Part I presents fundamentals of the Lagrangian and Hamiltonian formalism for mechanical systems, canonical transformations, action-angle variables, and then linear and nonlinear oscillators. The Hamiltonian for a circular accelerator is used to evaluate the equations of motion, the action, and betatron oscillations in an accelerator. From this base, we explore the impact of field errors and nonlinear resonances. This part ends with the concept of the distribution function and an introduction to the kinetic equation to describe large ensembles of charged particles and to supplement the previous single-particle analysis of beam dynamics. Part II focuses on classical electromagnetism and begins with an analysis of the electromagnetic field from relativistic beams, both in vacuum and in a resistive pipe. Plane electromagne...
The classical theory of fields electromagnetism
Helrich, Carl S
2012-01-01
The study of classical electromagnetic fields is an adventure. The theory is complete mathematically and we are able to present it as an example of classical Newtonian experimental and mathematical philosophy. There is a set of foundational experiments, on which most of the theory is constructed. And then there is the bold theoretical proposal of a field-field interaction from James Clerk Maxwell. This textbook presents the theory of classical fields as a mathematical structure based solidly on laboratory experiments. Here the student is introduced to the beauty of classical field theory as a gem of theoretical physics. To keep the discussion fluid, the history is placed in a beginning chapter and some of the mathematical proofs in the appendices. Chapters on Green’s Functions and Laplace’s Equation and a discussion of Faraday’s Experiment further deepen the understanding. The chapter on Einstein’s relativity is an integral necessity to the text. Finally, chapters on particle motion and waves in a dis...
Development of a strong electromagnet wiggler
International Nuclear Information System (INIS)
Burns, M.J.; Deis, G.A.; Holmes, R.H.; Van Maren, R.D.; Halbach, K.
1987-01-01
The Strong Electromagnet (SEM) wiggler is a permanent magnet-assisted electromagnet under development at the Lawrence Livermore National Laboratory (LLNL) as part of the Induction Linac Free-Electron-Laser (IFEL) program. This concept uses permanent magnets within the wiggler to provide a reverse bias flux in the iron and thus delay the onset of magnetic saturation. The electromagnet coils determine the wiggler field and operate at low current densities by virtue of their placement away from the midplane. We describe here the design approach used and test data from a 7-period wiggler prototype that includes curved pole tips to provide wiggle-plane focusing. 7 refs
Atom collisions in a strong electromagnetic field
International Nuclear Information System (INIS)
Smirnov, V.S.; Chaplik, A.V.
1976-01-01
It is shown that the long-range part of interatomic interaction is considerably altered in a strong electromagnetic field. Instead of the van der Waals law the potential asymptote can best be described by a dipole-dipole R -3 law. Impact broadening and the line shift in a strong nonresonant field are calculated. The possibility of bound states of two atoms being formed in a strong light field is discussed
Fast Atom Ionization in Strong Electromagnetic Radiation
Apostol, M.
2018-05-01
The Goeppert-Mayer and Kramers-Henneberger transformations are examined for bound charges placed in electromagnetic radiation in the non-relativistic approximation. The consistent inclusion of the interaction with the radiation field provides the time evolution of the wavefunction with both structural interaction (which ensures the bound state) and electromagnetic interaction. It is shown that in a short time after switching on the high-intensity radiation the bound charges are set free. In these conditions, a statistical criterion is used to estimate the rate of atom ionization. The results correspond to a sudden application of the electromagnetic interaction, in contrast with the well-known ionization probability obtained by quasi-classical tunneling through classically unavailable non-stationary states, or other equivalent methods, where the interaction is introduced adiabatically. For low-intensity radiation the charges oscillate and emit higher-order harmonics, the charge configuration is re-arranged and the process is resumed. Tunneling ionization may appear in these circumstances. Extension of the approach to other applications involving radiation-induced charge emission from bound states is discussed, like ionization of molecules, atomic clusters or proton emission from atomic nuclei. Also, results for a static electric field are included.
Electromagnetic radiation from strong Langmuir turbulence
International Nuclear Information System (INIS)
Akimoto, K.; Rowland, H.L.; Papadopoulos, K.
1988-01-01
A series of computer simulations is reported showing the generation of electromagnetic radiation by strong Langmuir turbulence. The simulations were carried out with a fully electromagnetic 2 1/2 -dimensional fluid code. The radiation process takes place in two stages that reflect the evolution of the electrostatic turbulence. During the first stage while the electrostatic turbulence is evolving from an initial linear wave packet into a planar soliton, the radiation is primarily at ω/sub e/. During the second stage when transverse instabilities lead to the collapse and dissipation of the solitons, 2ω/sub e/ and ω/sub e/ radiation are comparable, and 3ω/sub e/ is also present. The radiation power at ω = 2ω/sub e/ is in good agreement with theoretical predictions for electromagnetic emissions by collapsing solitons
Electromagnetic processes in strong crystalline fields
2007-01-01
We propose a number of new investigations on aspects of radiation from high energy electron and positron beams (10-300 GeV) in single crystals and amorphous targets. The common heading is radiation emission by electrons and positrons in strong electromagnetic fields, but as the setup is quite versatile, other related phenomena in radiation emission can be studied as well. The intent is to clarify the role of a number of important aspects of radiation in strong fields as e.g. observed in crystals. We propose to measure trident 'Klein-like' production in strong crystalline fields, 'crystalline undulator' radiation, 'sandwich' target phenomena, LPM suppression of pair production as well as axial and planar effects in contributions of spin to the radiation.
Unification of electromagnetic, strong and weak interaction
International Nuclear Information System (INIS)
Duong Van Phi; Duong Anh Duc
1993-09-01
The Unification of Electromagnetic, Strong and Weak Interactions is realized in the framework of the Quantum Field Theory, established in an 8-dimensional Unified Space. Two fundamental, spinor and vector field equations are considered. The first of the matter particles and the second is of the gauge particles. Interaction Lagrangians are formed from the external and internal currents and the external and internal vector field operators. Generators of the local gauge transformations are the combinations of the matrices of the first field equation. (author). 15 refs
Strong and Electromagnetic Interactions at SPS Energies
Ribicki, Andrzej
2009-01-01
Particle production in peripheral Pb+Pb collisions has been measured at a beam energy of 158 GeV per nucleon, corresponding to psNN 17.3 GeV. The measurements provide full double differential coverage in a wide range of longitudinal and transverse momenta, including the central (“mid-rapidity”) area and extending far into the projectile fragmentation region. The resulting analysis shows the heavy ion reaction as a mixture of different processes. In particular, surprising phenomena, like the presence of large and strongly varying structures in the shape of the double differential cross section d2s /dxFd pT , are induced by the final state electromagnetic interaction between produced particles and the charged spectator system. This effect is largest at low transverse momenta, where it results in a deep valley in the xF -dependence of the produced p+/p− ratio. The basic characteristics of the electromagnetic phenomenon described above agree with the results of a theoretical analysis, performed by means of ...
Electromagnetic modes in cold magnetized strongly coupled plasmas
Tkachenko, I. M.; Ortner, J.; Rylyuk, V. M.
1999-01-01
The spectrum of electromagnetic waves propagating in a strongly coupled magnetized fully ionized hydrogen plasma is found. The ion motion and damping being neglected, the influence of the Coulomb coupling on the electromagnetic spectrum is analyzed.
Classical electromagnetic radiation of the Dirac electron
Lanyi, G.
1973-01-01
A wave-function-dependent four-vector potential is added to the Dirac equation in order to achieve conservation of energy and momentum for a Dirac electron and its emitted electromagnetic field. The resultant equation contains solutions which describe transitions between different energy states of the electron. As a consequence it is possible to follow the space-time evolution of such a process. This evolution is shown in the case of the spontaneous emission of an electromagnetic field by an electron bound in a hydrogen-like atom. The intensity of the radiation and the spectral distribution are calculated for transitions between two eigenstates. The theory gives a self-consistent deterministic description of some simple radiation processes without using quantum electrodynamics or the correspondence principle.
Problems in classical electromagnetism 157 exercises with solutions
Macchi, Andrea; Pegoraro, Francesco
2017-01-01
This book contains 157 problems in classical electromagnetism, most of them new and original compared to those found in other textbooks. Each problem is presented with a title in order to highlight its inspiration in different areas of physics or technology, so that the book is also a survey of historical discoveries and applications of classical electromagnetism. The solutions are complete and include detailed discussions, which take into account typical questions and mistakes by the students. Without unnecessary mathematical complexity, the problems and related discussions introduce the student to advanced concepts such as unipolar and homopolar motors, magnetic monopoles, radiation pressure, angular momentum of light, bulk and surface plasmons, radiation friction, as well as to tricky concepts and ostensible ambiguities or paradoxes related to the classical theory of the electromagnetic field. With this approach the book is both a teaching tool for undergraduates in physics, mathematics and electric engine...
International Nuclear Information System (INIS)
Boyer, T.H.
1975-01-01
The theory of classical electrodynamics with classical electromagnetic zero-point radiation is outlined here under the title random electrodynamics. The work represents a reanalysis of the bounds of validity of classical electron theory which should sharpen the understanding of the connections and distinctions between classical and quantum theories. The new theory of random electrodynamics is a classical electron theory involving Newton's equations for particle motion due to the Lorentz force, and Maxwell's equations for the electromagnetic fields with point particles as sources. However, the theory departs from the classical electron theory of Lorentz in that it adopts a new boundary condition on Maxwell's equations. It is assumed that the homogeneous boundary condition involves random classical electromagnetic radiation with a Lorentz-invariant spectrum, classical electromagnetic zero-point radiation. The implications of random electrodynamics for atomic structure, atomic spectra, and particle-interference effects are discussed on an order-of-magnitude or heuristic level. Some detailed mathematical connections and some merely heuristic connections are noted between random electrodynamics and quantum theory. (U.S.)
Against dogma: On superluminal propagation in classical electromagnetism
Weatherall, James Owen
2014-11-01
It is deeply entrenched dogma that relativity theory prohibits superluminal propagation. It is also experimentally well-established that under some circumstances, classical electromagnetic fields propagate through a dielectric medium with superluminal group velocities and superluminal phase velocities. But it is usually claimed that these superluminal velocities do not violate the relativistic prohibition. Here I analyze electromagnetic fields in a dielectric medium within a framework for understanding superluminal propagation recently developed by Geroch (1996, 2011) and elaborated by Earman (2014). I will argue that for some parameter values, electromagnetic fields do propagate superluminally in the Geroch-Earman sense.
On the Galilean Non-Invariance of Classical Electromagnetism
Preti, Giovanni; de Felice, Fernando; Masiero, Luca
2009-01-01
When asked to explain the Galilean non-invariance of classical electromagnetism on the basis of pre-relativistic considerations alone, students--and sometimes their teachers too--may face an impasse. Indeed, they often argue that a pre-relativistic physicist could most obviously have provided the explanation "at a glance", on the basis of the…
Relativistic rapprochement of electromagnetic and strong interactions
International Nuclear Information System (INIS)
Strel'tsov, V.N.
1995-01-01
On the basis of the Lienard-Wiechert potential and the relativistic Yukawa potential it is shown that the corresponding interactions with velocity growth increase differently (the electromagnetic one increases faster). According to preliminary estimations they are equivalent, at distances of the 'action radius' of nuclear forces, at γ≅ 960, where γ is the Lorentz factor. 2 refs
Path integral approach to electron scattering in classical electromagnetic potential
International Nuclear Information System (INIS)
Xu Chuang; Feng Feng; Li Ying-Jun
2016-01-01
As is known to all, the electron scattering in classical electromagnetic potential is one of the most widespread applications of quantum theory. Nevertheless, many discussions about electron scattering are based upon single-particle Schrodinger equation or Dirac equation in quantum mechanics rather than the method of quantum field theory. In this paper, by using the path integral approach of quantum field theory, we perturbatively evaluate the scattering amplitude up to the second order for the electron scattering by the classical electromagnetic potential. The results we derive are convenient to apply to all sorts of potential forms. Furthermore, by means of the obtained results, we give explicit calculations for the one-dimensional electric potential. (paper)
Classical electromagnetic field theory in the presence of magnetic sources
Chen, Wen-Jun; Li, Kang; Naón, Carlos
2001-01-01
Using two new well defined 4-dimensional potential vectors, we formulate the classical Maxwell's field theory in a form which has manifest Lorentz covariance and SO(2) duality symmetry in the presence of magnetic sources. We set up a consistent Lagrangian for the theory. Then from the action principle we get both Maxwell's equation and the equation of motion of a dyon moving in the electro-magnetic field.
Interaction of strong electromagnetic fields with atoms
International Nuclear Information System (INIS)
Brandi, H.S.; Davidovich, L.; Zagury, N.
1982-06-01
Several non-linear processes involvoing the interaction of atoms with strong laser fields are discussed, with particular emphasis on the ionization problem. Non-perturbative methods which have been proposed to tackle this problem are analysed, and shown to correspond to an expansion in the intra-atomic potential. The relation between tunneling and multiphoton absorption as ionization mechanisms, and the generalization of Einstein's photoelectric equation to the strong-field case are discussed. (Author) [pt
Strong and electromagnetic interactions in hadron systems
International Nuclear Information System (INIS)
Aissat, N.; Amghar, A.; Cano, F.; Gonzalez, F.; Noguera, S.; Carbonell, J.; Desplanques, B.; Silvestre-Brac, B.; Karmanov, V.; Mathiot, J.F.
1997-01-01
The pionic strong decay amplitudes of baryon resonances are studied in a constituent quark model. Particular attention is given to the operator describing the transition. The nucleon form factors are calculated in a non-relativistic approach, with emphasis on the highest momentum transfers. The aim is to determine the ingredients that are essential in getting correct results and are likely to be required for a more realistic estimate in a fully relativistic approach. The deuteron form factors have been calculated in the light-front approach using wave functions determined in a perturbative way. The derivation of the neutron charge form factor from the deuteron structure function, A(q 2 ), is reanalyzed including further mesonic exchange contributions. (authors)
International Nuclear Information System (INIS)
Boyer, Timothy H
2016-01-01
Electromagnetism is a relativistic theory, and one must exercise care in coupling this theory with nonrelativistic classical mechanics and with nonrelativistic classical statistical mechanics. Indeed historically, both the blackbody radiation spectrum and diamagnetism within classical theory have been misunderstood because of two crucial failures: (1) the neglect of classical electromagnetic zero-point radiation, and (2) the use of erroneous combinations of nonrelativistic mechanics with relativistic electrodynamics. Here we review the treatment of classical blackbody radiation, and show that the presence of Lorentz-invariant classical electromagnetic zero-point radiation can explain both the Planck blackbody spectrum and Landau diamagnetism at thermal equilibrium within classical electromagnetic theory. The analysis requires that relativistic electromagnetism is joined appropriately with simple nonrelativistic mechanical systems which can be regarded as the zero-velocity limits of relativistic systems, and that nonrelativistic classical statistical mechanics is applied only in the low-frequency limit when zero-point energy makes no contribution. (paper)
Propagation of strong electromagnetic beams in inhomogeneous plasmas
Energy Technology Data Exchange (ETDEWEB)
Ferrari, A; Massaglia, S [Consiglio Nazionale delle Ricerche, Turin (Italy). Lab. di Cosmo-Geofisica; Turin Univ. (Italy). Ist. di Fisica Generale)
1980-09-01
We study some simple aspects of nonlinear propagation of relativistically strong electromagnetic beams in inhomogeneous plasmas, especially in connection with effects of beam self-trapping in extended extragalactic radio sources. The two effects of (i) long scale longitudinal and radial inhomogeneities inherent to the plasma and (ii) radial inhomogeneities produced by the ponderomotive force of the beam itself are investigated.
Electromagnetic pulses in a strongly magnetized electron-positron plasma
International Nuclear Information System (INIS)
Yu, M.Y.; Rao, N.N.
1985-01-01
The conditions for the existence of large-amplitude localized electromagnetic wave pulses in an electron-positron plasma penetrated by a very strong ambient magnetic field are obtained. It is shown that such pulses can exist in pulsar polar magnetospheres. 12 references
Spontaneous electromagnetic emission from a strongly localized plasma flow.
Tejero, E M; Amatucci, W E; Ganguli, G; Cothran, C D; Crabtree, C; Thomas, E
2011-05-06
Laboratory observations of electromagnetic ion-cyclotron waves generated by a localized transverse dc electric field are reported. Experiments indicate that these waves result from a strong E×B flow inhomogeneity in a mildly collisional plasma with subcritical magnetic field-aligned current. The wave amplitude scales with the magnitude of the applied radial dc electric field. The electromagnetic signatures become stronger with increasing plasma β, and the radial extent of the power is larger than that of the electrostatic counterpart. Near-Earth space weather implications of the results are discussed.
Nonlinear properties of gated graphene in a strong electromagnetic field
Energy Technology Data Exchange (ETDEWEB)
Avetisyan, A. A., E-mail: artakav@ysu.am; Djotyan, A. P., E-mail: adjotyan@ysu.am [Yerevan State University, Department of Physics (Armenia); Moulopoulos, K., E-mail: cos@ucy.ac.cy [University of Cyprus, Department of Physics (Cyprus)
2017-03-15
We develop a microscopic theory of a strong electromagnetic field interaction with gated bilayer graphene. Quantum kinetic equations for density matrix are obtained using a tight binding approach within second quantized Hamiltonian in an intense laser field. We show that adiabatically changing the gate potentials with time may produce (at resonant photon energy) a full inversion of the electron population with high density between valence and conduction bands. In the linear regime, excitonic absorption of an electromagnetic radiation in a graphene monolayer with opened energy gap is also studied.
Dispersion relation of linearly polarized strong electromagnetic waves
Energy Technology Data Exchange (ETDEWEB)
Ferrari, A; Massaglia, S [Consiglio Nazionale delle Ricerche, Turin (Italy). Lab. di Cosmo-Geofisica; Dobrowolny, M [Comitato Nazionale per l' Energia Nucleaire, Frascati (Italy). Lab. Plasma Spazio
1975-12-15
A numerical study is presented of the dispersion relation of linearly polarized strong electromagnetic waves in a cold electron plasma. The nonlinear effects introduced by the relativistic motion of electrons are: (1) the dispersion relation depends explicitly on the field strength ..cap alpha..=eE/sub 0//mc..omega../sub 0/, and (2) the propagation of modes with frequencies below the formal electron plasma frequency is allowed.
Geiger-Nuttall Law for Nuclei in Strong Electromagnetic Fields
Delion, D. S.; Ghinescu, S. A.
2017-11-01
We investigate the influence of a strong laser electromagnetic field on the α -decay rate by using the Hennenberger frame of reference. We introduce an adimensional parameter D =S0/R0, where R0 is the geometrical nuclear radius and S0˜√{I }/ω2 is a length parameter depending on the laser intensity I and frequency ω . We show that the barrier penetrability has a strong increase for intensities corresponding to D >Dcrit=1 , due to the fact that the resulting Coulomb potential becomes strongly anisotropic even for spherical nuclei. As a consequence, the contribution of the monopole term increases the barrier penetrability by 2 orders of magnitude, while the total contribution has an effect of 6 orders of magnitude at D ˜3 Dcrit. In the case of deformed nuclei, the electromagnetic field increases the penetrability by an additional order of magnitude for a quadrupole deformation β2˜0.3 . The influence of the electromagnetic field can be expressed in terms of a shifted Geiger-Nuttal law by a term depending on S0 and deformation.
Beta decay and other processes in strong electromagnetic fields
International Nuclear Information System (INIS)
Akhmedov, E. Kh.
2011-01-01
We consider effects of the fields of strong electromagnetic waves on various characteristics of quantum processes. After a qualitative discussion of the effects of external fields on the energy spectra and angular distributions of the final-state particles as well as on the total probabilities of the processes (such as decay rates and total cross sections), we present a simple method of calculating the total probabilities of processes with production of nonrelativistic charged particles. Using nuclear β decay as an example, we study the weak- and strong-field limits, as well as the field-induced β decay of nuclei stable in the absence of the external fields, both in the tunneling and multiphoton regimes. We also consider the possibility of accelerating forbidden nuclear β decays by lifting the forbiddeness due to the interaction of the parent or daughter nuclei with the field of a strong electromagnetic wave. It is shown that for currently attainable electromagnetic fields all effects on total β-decay rates are unobservably small.
Classical particles with spin in electromagnetic and gravitational fields
International Nuclear Information System (INIS)
Amorim, R.M. de.
1977-02-01
Following a review of several problems connected with classical particles with intrinsic angular momentum are reproduced the Frenkel equations (with the condition S sup(μν)U sub(ν)=0) by means of a holonomic variational principle, and have related them to Bargann, Michel and Tededgie equations. The treatment is then generalized to the case in wich S sup(μν)U sub(ν)=0 and the resulting equation coincide in the linearized limit with those obtained by Suttorp and de Groot. Also, by using variational principles, the generalizations to Frenkel equations are obtained, as well as to those of Suttorp and de Groot when electromagnetic and gravitational interactions are considered. Finally, those equations are analysed according to a scheme proposed by Oliveira and Tiommo where the gravitational interactions are described by gravielectric and gravimagnetic fields. The analogies in these equations of motion between the gravitational and eletromagnetic interactions, in the case in which the particle has a giromagnetic factor g=1, are shown. The last results complete a previous study by wald. (Author) [pt
Strong interactions and electromagnetism in low-energy hadron physics
International Nuclear Information System (INIS)
Kubis, B.
2002-10-01
In the present work, we study various aspects of the entanglement of the strong and electromagnetic interactions as it is manifest in low-energy hadron physics. In the framework of chiral perturbation theory, two aspects are investigated: the test of the structure of baryons as probed by external electromagnetic currents, and the modification of reactions mediated by the strong interactions in the presence of internal (virtual) photons. In the first part of this work, we study the electromagnetic form factors of nucleons and the ground state baryon octet, as well as strangeness form factors of the nucleon. Emphasis is put on the comparison of a new relativistic scheme for the calculation of loop diagrams to the heavy-baryon formalism, and on the convergence of higher-order corrections in both schemes. The new scheme is shown to yield both a phenomenologically more successful description of the data and better convergence behaviour. In the second part, we study isospin violation in pion-kaon scattering as mediated by virtual photon effects and the light quark mass difference. This investigation is of particular importance for the extraction of scattering lengths from measurements of lifetime and energy levels in pion-kaon atoms. The isospin breaking corrections are shown to be small and sufficiently well under control. (orig.)
On the Classical Coupling between Gravity and Electromagnetism
Directory of Open Access Journals (Sweden)
Maria Becker
2015-06-01
Full Text Available Coupling between electromagnetism and gravity, manifested as the distorted Coulomb field of a charge distribution in a gravitational field, has never been observed. A physical system consisting of an electron in a charged shell provides a coupling that is orders of magnitude stronger than for any previously-considered system. A shell voltage of one megavolt is required to establish a gravitationally-induced electromagnetic force equal in magnitude to the force of gravity on an electron. The experimental feasibility of detecting these forces on an electron is discussed. The effect establishes a relation between Einstein’s energy-mass equivalence and the coupling between electromagnetism and gravity.
International Nuclear Information System (INIS)
Galvao, C.A.P.; Mignaco, J.A.
1994-01-01
The classical electromagnetic theory is analysed which corresponds to the two-dimensional quantum electrodynamics with massless spinor fields (Schwinger model). The chiral anomaly is introduced as a currents property, which in the two-dimensional spinor fields are duality related. It is also shown that the resulting classical theory is consistent. (author). 5 refs
On All Strong Kleene Generalizations of Classical Logic
S. Wintein (Stefan)
2016-01-01
textabstractBy using the notions of exact truth (‘true and not false’) and exact falsity (‘false and not true’), one can give 16 distinct definitions of classical consequence. This paper studies the class of relations that results from these definitions in settings that are paracomplete,
International Nuclear Information System (INIS)
Boyer, T.H.
1984-01-01
A derivation of Planck's spectrum including zero-point radiation is given within classical physics from recent results involving the thermal effects of acceleration through classical electromagnetic zero-point radiation. A harmonic electric-dipole oscillator undergoing a uniform acceleration a through classical electromagnetic zero-point radiation responds as would the same oscillator in an inertial frame when not in zero-point radiation but in a different spectrum of random classical radiation. Since the equivalence principle tells us that the oscillator supported in a gravitational field g = -a will respond in the same way, we see that in a gravitational field we can construct a perpetual-motion machine based on this different spectrum unless the different spectrum corresponds to that of thermal equilibrium at a finite temperature. Therefore, assuming the absence of perpetual-motion machines of the first kind in a gravitational field, we conclude that the response of an oscillator accelerating through classical zero-point radiation must be that of a thermal system. This then determines the blackbody radiation spectrum in an inertial frame which turns out to be exactly Planck's spectrum including zero-point radiation
Note on Inverse Bremsstrahlung in a Strong Electromagnetic Field
Bethe, H. A.
1972-09-01
The collisional energy loss of an electron undergoing forced oscillation in an electromagnetic field behaves quite differently in the low and high intensity limits. ... It is shown that in the case of an electromagnetic field v {sub o} >> v {sub t} the rate of transfer is much slower, and actually decreases with the strength of the field.
Classical and quantum models of strong cosmic censorship
International Nuclear Information System (INIS)
Moncrief, V.E.
1983-01-01
The cosmic censorship conjecture states that naked singularities should not evolve from regular initial conditions in general relativity. In its strong form the conjecture asserts that space-times with Cauchy horizons must always be unstable and thus that the generic solution of Einstein's equations must be inextendible beyond its maximal Cauchy development. In this paper it is shown that one can construct an infinite-dimensional family of extendible cosmological solutions similar to Taub-NUT space-time; however, each of these solutions is unstable in precisely the way demanded by strong cosmic censorship. Finally it is shown that quantum fluctuations in the metric always provide (though in an unexpectedly subtle way) the ''generic perturbations'' which destroy the Cauchy horizons in these models. (author)
Classical and quantum models of strong cosmic censorship
Energy Technology Data Exchange (ETDEWEB)
Moncrief, V.E. (Yale Univ., New Haven, CT (USA). Dept. of Physics)
1983-04-01
The cosmic censorship conjecture states that naked singularities should not evolve from regular initial conditions in general relativity. In its strong form the conjecture asserts that space-times with Cauchy horizons must always be unstable and thus that the generic solution of Einstein's equations must be inextendible beyond its maximal Cauchy development. In this paper it is shown that one can construct an infinite-dimensional family of extendible cosmological solutions similar to Taub-NUT space-time; however, each of these solutions is unstable in precisely the way demanded by strong cosmic censorship. Finally it is shown that quantum fluctuations in the metric always provide (though in an unexpectedly subtle way) the ''generic perturbations'' which destroy the Cauchy horizons in these models.
The non-intuitive 1/2 Thomas factor: a heuristic argument with classical electromagnetism
International Nuclear Information System (INIS)
Chrysos, M
2006-01-01
We present a heuristic argument to deduce the non-intuitive 1/2 Thomas factor for an atomic electron revolving in its orbit about the nucleus. The argument, which is simple, pedagogical and accessible to physics beginners, uses elementary notions of classical electromagnetism rather than the advanced relativity concepts which are needed in any standard textbook derivation
Norbury, John W.
1989-01-01
The invariance of classical electromagnetism under charge-conjugation, parity, and time-reversal (CPT) is studied by considering the motion of a charged particle in electric and magnetic fields. Upon applying CPT transformations to various physical quantities and noting that the motion still behaves physically demonstrates invariance.
International Nuclear Information System (INIS)
Yamaguchi-Sekino, Sachiko; Sekino, Masaki; Ueno, Shoogo
2011-01-01
Humans are exposed daily to artificial and naturally occurring magnetic fields that originate from many different sources. We review recent studies that examine the biological effects of and medical applications involving electromagnetic fields, review the properties of static and pulsed electromagnetic fields that affect biological systems, describe the use of a pulsed electromagnetic field in combination with an anticancer agent as an example of a medical application that incorporates an electromagnetic field, and discuss the recently updated safety guidelines for static electromagnetic fields. The most notable modifications to the 2009 International Commission on Non-Ionizing Radiation Protection guidelines are the increased exposure limits, especially for those who work with or near electromagnetic fields (occupational exposure limits). The recommended increases in exposure were determined using recent scientific evidence obtained from animal and human studies. Several studies since the 1994 publication of the guidelines have examined the effects on humans after exposure to high static electromagnetic fields (up to 9.4 tesla), but additional research is needed to ascertain further the safety of strong electromagnetic fields. (author)
Khrennikov, Andrei
2011-09-01
We propose a model of quantum-like (QL) processing of mental information. This model is based on quantum information theory. However, in contrast to models of "quantum physical brain" reducing mental activity (at least at the highest level) to quantum physical phenomena in the brain, our model matches well with the basic neuronal paradigm of the cognitive science. QL information processing is based (surprisingly) on classical electromagnetic signals induced by joint activity of neurons. This novel approach to quantum information is based on representation of quantum mechanics as a version of classical signal theory which was recently elaborated by the author. The brain uses the QL representation (QLR) for working with abstract concepts; concrete images are described by classical information theory. Two processes, classical and QL, are performed parallely. Moreover, information is actively transmitted from one representation to another. A QL concept given in our model by a density operator can generate a variety of concrete images given by temporal realizations of the corresponding (Gaussian) random signal. This signal has the covariance operator coinciding with the density operator encoding the abstract concept under consideration. The presence of various temporal scales in the brain plays the crucial role in creation of QLR in the brain. Moreover, in our model electromagnetic noise produced by neurons is a source of superstrong QL correlations between processes in different spatial domains in the brain; the binding problem is solved on the QL level, but with the aid of the classical background fluctuations. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.
Classical trajectory perspective of atomic ionization in strong laser fields. Semiclassical modeling
International Nuclear Information System (INIS)
Liu, Jie
2014-01-01
Dealing with timely and interesting issues in strong laser physics. Illustrates complex strong field atomic ionization with the simple semiclassical model of classical trajectory perspective for the first time. Provides a theoretical model that can be used to account for recent experiments. The ionization of atoms and molecules in strong laser fields is an active field in modern physics and has versatile applications in such as attosecond physics, X-ray generation, inertial confined fusion (ICF), medical science and so on. Classical Trajectory Perspective of Atomic Ionization in Strong Laser Fields covers the basic concepts in this field and discusses many interesting topics using the semiclassical model of classical trajectory ensemble simulation, which is one of the most successful ionization models and has the advantages of a clear picture, feasible computing and accounting for many exquisite experiments quantitatively. The book also presents many applications of the model in such topics as the single ionization, double ionization, neutral atom acceleration and other timely issues in strong field physics, and delivers useful messages to readers with presenting the classical trajectory perspective on the strong field atomic ionization. The book is intended for graduate students and researchers in the field of laser physics, atom molecule physics and theoretical physics. Dr. Jie Liu is a professor of Institute of Applied Physics and Computational Mathematics, China and Peking University.
Electromagnetic processes in strong crystalline fields - NA63 Status Report
Ugerhoj, Ulrik
2009-01-01
Results obtained in the framework of the NA63 experiment cite{Ande05} at CERN are reported. Analysis of the trident production in the strong crystalline fields of single Ge crystals is completed. Yields in the random ('amorphous') orientation are in good agreement with calculations, and in the aligned case the production is enhanced by about a factor 3 compared to a Ge amorphous material. Results on the formation lengths of several microns for the production of GeV photons from ultrarelativistic electrons have been published. In 2008 we performed a measurement of resonance phenomena in structured targets and studied a possible change in restricted energy loss in thin solid state detectors, for sufficiently high values of the Lorentz factor. The plans for 2009 are to study the 'semi-bare electron' from radiation emission in thin targets and to study the spin-flip mechanisms in radiation emission, relevant for beamstrahlung phenomena in future linear colliders such as CLIC.
Understanding zero-point energy in the context of classical electromagnetism
International Nuclear Information System (INIS)
Boyer, Timothy H
2016-01-01
Today’s textbooks of electromagnetism give the particular solution to Maxwell’s equations involving the integral over the charge and current sources at retarded times. However, the texts fail to emphasise that the choice of the incoming-wave boundary conditions corresponding to solutions of the homogeneous Maxwell equations must be made based upon experiment. Here we discuss the role of these incoming-wave boundary conditions for an experimenter with a hypothetical charged harmonic oscillator as his equipment. We describe the observations of the experimenter when located near a radio station or immersed in thermal radiation at temperature T . The classical physicists at the end of the 19th century chose the incoming-wave boundary conditions for the homogeneous Maxwell equations based upon the experimental observations of Lummer and Pringsheim which measured only the thermal radiation which exceeded the random radiation surrounding their measuring equipment; the physicists concluded that they could take the homogeneous solutions to vanish at zero temperature. Today at the beginning of the 21st century, classical physicists must choose the incoming-wave boundary conditions for the homogeneous Maxell equations to correspond to the full radiation spectrum revealed by the recent Casimir force measurements which detect all the radiation surrounding conducting parallel plates, including the radiation absorbed and emitted by the plates themselves. The random classical radiation spectrum revealed by the Casimir force measurements includes electromagnetic zero-point radiation, which is missing from the spectrum measured by Lummer and Pringsheim, and which cannot be eliminated by going to zero temperature. This zero-point radiation will lead to zero-point energy for all systems which have electromagnetic interactions. Thus the choice of the incoming-wave boundary conditions on the homogeneous Maxwell equations is intimately related to the ideas of zero-point energy and
International Nuclear Information System (INIS)
Graham, D. B.; Robinson, P. A.; Cairns, Iver H.; Skjaeraasen, O.
2011-01-01
Large-scale simulations of wave packet collapse are performed by numerically solving the three-dimensional (3D) electromagnetic Zakharov equations, focusing on individual wave packet collapses and on wave packets that form in continuously driven strong turbulence. The collapse threshold is shown to decrease as the electron thermal speed ν e /c increases and as the temperature ratio T i /T e of ions to electrons decreases. Energy lost during wave packet collapse and dissipation is shown to depend on ν e /c. The dynamics of density perturbations after collapse are studied in 3D electromagnetic strong turbulence for a range of T i /T e . The structures of the Langmuir, transverse, and total electric field components of wave packets during strong turbulence are investigated over a range of ν e /c. For ν e /c e /c > or approx. 0.17, transverse modes become trapped in density wells and contribute significantly to the structure of the total electric field. At all ν e /c, the Langmuir energy density contours of wave packets are predominantly oblate (pancake shaped). The transverse energy density contours of wave packets are predominantly prolate (sausage shaped), with the major axis being perpendicular to the major axes of the Langmuir component. This results in the wave packet becoming more nearly spherical as ν e /c increases, and in turn generates more spherical density wells during collapse. The results obtained are compared with previous 3D electrostatic results and 2D electromagnetic results.
International Nuclear Information System (INIS)
Boreham, B. W.; Hora, H.
1997-01-01
We have recently developed a correspondence principle for electromagnetic interaction. When applied to laser interactions with electrons this correspondence principle identifies a critical laser intensity I*. This critical intensity is a transition intensity separating classical mechanical and quantum mechanical interaction regimes. In this paper we discuss the further application of I* to the interaction of bound electrons in atoms. By comparing I* with the ionisation threshold intensities as calculated from a cycle-averaged simple-atom model we conclude that I* can be usefully interpreted as a lower bound to the classical regime in studies of ionisation of gas atoms by intense laser beams
Classical integrability for three-point functions: cognate structure at weak and strong couplings
Energy Technology Data Exchange (ETDEWEB)
Kazama, Yoichi [Research Center for Mathematical Physics, Rikkyo University,Toshima-ku, Tokyo 171-8501 (Japan); Quantum Hadron Physics Laboratory, RIKEN Nishina Center, Wako 351-0198 (Japan); Institute of Physics, University of Tokyo, Komaba, Meguro-ku, Tokyo 153-8902 (Japan); Komatsu, Shota [Perimeter Institute for Theoretical Physics,31 Caroline Street North, Waterloo, Ontario, N2L 2Y5 (Canada); Nishimura, Takuya [Institute of Physics, University of Tokyo, Komaba, Meguro-ku, Tokyo 153-8902 (Japan)
2016-10-10
In this paper, we develop a new method of computing three-point functions in the SU(2) sector of the N=4 super Yang-Mills theory in the semi-classical regime at weak coupling, which closely parallels the strong coupling analysis. The structure threading two disparate regimes is the so-called monodromy relation, an identity connecting the three-point functions with and without the insertion of the monodromy matrix. We shall show that this relation can be put to use directly for the semi-classical regime, where the dynamics is governed by the classical Landau-Lifshitz sigma model. Specifically, it reduces the problem to a set of functional equations, which can be solved once the analyticity in the spectral parameter space is specified. To determine the analyticity, we develop a new universal logic applicable at both weak and strong couplings. As a result, compact semi-classical formulas are obtained for a general class of three-point functions at weak coupling including the ones whose semi-classical behaviors were not known before. In addition, the new analyticity argument applied to the strong coupling analysis leads to a modification of the integration contour, producing the results consistent with the recent hexagon bootstrap approach. This modification also makes the Frolov-Tseytlin limit perfectly agree with the weak coupling form.
Theoretical & Experimental Research in Weak, Electromagnetic & Strong Interactions
Energy Technology Data Exchange (ETDEWEB)
Nandi, Satyanarayan [Oklahoma State Univ., Stillwater, OK (United States); Babu, Kaladi [Oklahoma State Univ., Stillwater, OK (United States); Rizatdinova, Flera [Oklahoma State Univ., Stillwater, OK (United States); Khanov, Alexander [Oklahoma State Univ., Stillwater, OK (United States); Haley, Joseph [Oklahoma State Univ., Stillwater, OK (United States)
2015-09-17
The conducted research spans a wide range of topics in the theoretical, experimental and phenomenological aspects of elementary particle interactions. Theory projects involve topics in both the energy frontier and the intensity frontier. The experimental research involves energy frontier with the ATLAS Collaboration at the Large Hadron Collider (LHC). In theoretical research, novel ideas going beyond the Standard Model with strong theoretical motivations were proposed, and their experimental tests at the LHC and forthcoming neutrino facilities were outlined. These efforts fall into the following broad categories: (i) TeV scale new physics models for LHC Run 2, including left-right symmetry and trinification symmetry, (ii) unification of elementary particles and forces, including the unification of gauge and Yukawa interactions, (iii) supersummetry and mechanisms of supersymmetry breaking, (iv) superworld without supersymmetry, (v) general models of extra dimensions, (vi) comparing signals of extra dimensions with those of supersymmetry, (vii) models with mirror quarks and mirror leptons at the TeV scale, (viii) models with singlet quarks and singlet Higgs and their implications for Higgs physics at the LHC, (ix) new models for the dark matter of the universe, (x) lepton flavor violation in Higgs decays, (xi) leptogenesis in radiative models of neutrino masses, (xii) light mediator models of non-standard neutrino interactions, (xiii) anomalous muon decay and short baseline neutrino anomalies, (xiv) baryogenesis linked to nucleon decay, and (xv) a new model for recently observed diboson resonance at the LHC and its other phenomenological implications. The experimental High Energy Physics group has been, and continues to be, a successful and productive contributor to the ATLAS experiment at the LHC. Members of the group performed search for gluinos decaying to stop and top quarks, new heavy gauge bosons decaying to top and bottom quarks, and vector-like quarks
Sound absorption in a field of a strong electromagnetic wave in a quantizied magnetic field
International Nuclear Information System (INIS)
Chajkovskij, I.A.
1974-01-01
A coefficient of sound absorption GAMMA in a semiconductor and semi-metal in the quantized magnetic field is calculated for a system exposed to a field of strong electromagnetic radiation. The cases E parallel H and E orthogonal H are considered. Along with the already known strong oscillations of sound absorption in magnetic fields, the absorption spectrum GAMMAsub(par) and GAMMAsub(orth) shows new oscillations representing a manifestation of the quasi-energetic electron spectrum in the field of a strong electromagnetic wave. The oscillation height at E parallel H is modulated by the electromagnetic field. It is shown that the ratio GAMMAsub(par)/GAMMAsub(orth) allows the determination of the effective mass of the carriers
A Wigner quasi-distribution function for charged particles in classical electromagnetic fields
International Nuclear Information System (INIS)
Levanda, M.; Fleurov, V.
2001-01-01
A gauge-invariant Wigner quasi-distribution function for charged particles in classical electromagnetic fields is derived in a rigorous way. Its relation to the axial gauge is discussed, as well as the relation between the kinetic and canonical momenta in the Wigner representation. Gauge-invariant quantum analogs of Hamilton-Jacobi and Boltzmann kinetic equations are formulated for arbitrary classical electromagnetic fields in terms of the 'slashed' derivatives and momenta, introduced for this purpose. The kinetic meaning of these slashed quantities is discussed. We introduce gauge-invariant conditional moments and use them to derive a kinetic momentum continuity equation. This equation provides us with a hydrodynamic representation for quantum transport processes and a definition of the 'collision force'. The hydrodynamic equation is applied for the rotation part of the electron motion. The theory is illustrated by its application in three examples: Wigner quasi-distribution function and equations for an electron in a magnetic field and harmonic potential; Wigner quasi-distribution function for a charged particle in periodic systems using the kq representation; two Wigner quasi-distribution functions for heavy-mass polaron in an electric field
Energy Technology Data Exchange (ETDEWEB)
Porto, Stefano [Hamburg Univ. (Germany). 2. Inst. fuer Theoretische Physik; Hartin, Anthony [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Moortgat-Pick, Gudrid [Hamburg Univ. (Germany). 2. Inst. fuer Theoretische Physik; Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)
2013-04-15
Future linear colliders designs, ILC and CLIC, are expected to be powerful machines for the discovery of Physics Beyond the Standard Model and subsequent precision studies. However, due to the intense beams (high luminosity, high energy), strong electromagnetic fields occur in the beam-beam interaction region. In the context of precision high energy physics, the presence of such strong fields may yield sensitive corrections to the observed electron-positron processes. The Furry picture of quantum states gives a conceptually simple tool to treat physics processes in an external field. A generalization of the quasi-classical operator method (QOM) as an approximation is considered too.
International Nuclear Information System (INIS)
Bosanac, Slobodan Danko
2016-01-01
This book is devoted to theoretical methods used in the extreme circumstances of very strong electromagnetic fields. The development of high power lasers, ultrafast processes, manipulation of electromagnetic fields and the use of very fast charged particles interacting with other charges requires an adequate theoretical description. Because of the very strong electromagnetic field, traditional theoretical approaches, which have primarily a perturbative character, have to be replaced by descriptions going beyond them. In the book an extension of the semi-classical radiation theory and classical dynamics for particles is performed to analyze single charged atoms and dipoles submitted to electromagnetic pulses. Special attention is given to the important problem of field reaction and controlling dynamics of charges by an electromagnetic field.
Energy Technology Data Exchange (ETDEWEB)
Latyshev, A. V., E-mail: avlatyshev@mail.ru; Yushkanov, A. A. [Moscow State Regional University (Russian Federation)
2015-09-15
A distribution function for collisionless plasma is derived from the Vlasov kinetic equation in the quadratic approximation with respect to the electromagnetic field. Formulas for calculation of the electric current at an arbitrary temperature (arbitrary degree of degeneration of the electron gas) are deduced. The case of small wavenumbers is considered. It is shown that nonlinearity leads to the generation of an electric current directed along the wave vector. This longitudinal current is orthogonal to the classical transverse current, well known in the linear theory. A distribution function for collisionless quantum plasma is derived from the kinetic equation with the Wigner integral in the quadratic approximation with respect to the vector potential. Formulas for calculation of the electric current at an arbitrary temperature are deduced. The case of small wavenumbers is considered. It is shown that, at small values of the wavenumber, the value of the longitudinal current for quantum plasma coincides with that for classical plasma. The dimensionless currents in quantum and classical plasmas are compared graphically.
Achieving the classical Carnot efficiency in a strongly coupled quantum heat engine
Xu, Y. Y.; Chen, B.; Liu, J.
2018-02-01
Generally, the efficiency of a heat engine strongly coupled with a heat bath is less than the classical Carnot efficiency. Through a model-independent method, we show that the classical Carnot efficiency is achieved in a strongly coupled quantum heat engine. First, we present the first law of quantum thermodynamics in strong coupling. Then, we show how to achieve the Carnot cycle and the classical Carnot efficiency at strong coupling. We find that this classical Carnot efficiency stems from the fact that the heat released in a nonequilibrium process is balanced by the absorbed heat. We also analyze the restrictions in the achievement of the Carnot cycle. The first restriction is that there must be two corresponding intervals of the controllable parameter in which the corresponding entropies of the work substance at the hot and cold temperatures are equal, and the second is that the entropy of the initial and final states in a nonequilibrium process must be equal. Through these restrictions, we obtain the positive work conditions, including the usual one in which the hot temperature should be higher than the cold, and a new one in which there must be an entropy interval at the hot temperature overlapping that at the cold. We demonstrate our result through a paradigmatic model—a two-level system in which a work substance strongly interacts with a heat bath. In this model, we find that the efficiency may abruptly decrease to zero due to the first restriction, and that the second restriction results in the control scheme becoming complex.
Periodicity and chaos in strongly perturbed classical orbitals for Coulomb interactions
Energy Technology Data Exchange (ETDEWEB)
Klar, H
1986-01-01
Within the framework of classical mechanics two prototypes of strongly perturbed orbitals, the diamagnetism in hydrogen and electronic double excitation, are analyzed near critical phase space points (fixed points). The motion of the hydrogen electron under the joint influence of the Coulomb field and the magnetic field is periodic for any field strengths. For a two-electron atom however the author finds a chaotic time evolution of the electron pair correlation, causing presumably irregular spectral patterns. (Auth.).
Energy Technology Data Exchange (ETDEWEB)
Han, Song; Yang, Helin [College of Physical Science and Technology, Central China Normal University, Wuhan (China); Cong, Lonqing; Singh, Ranjan [Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore (Singapore); Centre for Disruptive Photonic Technologies, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore (Singapore); Gao, Fei [Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore (Singapore)
2016-05-15
Toroidal multipoles have recently been explored in various scientific communities, ranging from atomic and molecular physics, electrodynamics, and solid-state physics to biology. Here we experimentally and numerically demonstrate a three-dimensional toroidal metamaterial where two different toroidal dipoles along orthogonal directions have been observed. The chosen toroidal metamaterial also simultaneously supports Fano resonance and the classical analog of electromagnetically induced transparency (EIT) phenomena in the transmission spectra that originate from the electric-toroidal dipole and electric-magnetic dipole destructive interference. The intriguing properties of the toroidal resonances may open up avenues for applications in toroidal moments generator, sensing and slow-light devices. (copyright 2016 by WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)
International Nuclear Information System (INIS)
Alinejad, H.; Robinson, P. A.; Cairns, I. H.; Skjaeraasen, O.; Sobhanian, S.
2007-01-01
Nucleating and collapsing wave packets relevant to electromagnetic strong plasma turbulence are studied theoretically in two dimensions. Model collapsing Langmuir and transverse potentials are constructed as superpositions of approximate eigenstates of a spherically symmetric density well. Electrostatic and electromagnetic potentials containing only components with azimuthal quantum numbers m=0, 1, 2 are found to give a good representation of the electric fields of nucleating collapsing wave packets in turbulence simulations. The length scales of these trapped states are related to the electron thermal speed v e and the length scale of the density well. It is shown analytically that the electromagnetic trapped states change with v e and that for v e e > or approx. 0.17c, the Langmuir and transverse modes remain coupled during collapse, with autocorrelation lengths in a constant ratio. An investigation of energy transfer to packets localized in density wells shows that the strongest power transfer to the nucleating state occurs for Langmuir waves. Energy transitions between different trapped and free states for collapsing wave packets are studied, and the transition rate from trapped Langmuir to free plane electromagnetic waves is calculated and related to the emission of electromagnetic waves at the plasma frequency
Gu, Yan; Wang, Jiao
1997-02-01
We study relaxation of an ensemble of cat maps with initially localized phase-space distributions. Calculations of the coarse-grained entropy Sɛ ( t) for both classical and quantum motions are presented. It is shown that, within the relaxation period, both classical and quantum entropies increase with a nearly constant rate which can be identified as the largest Lyapunov exponent of the classical cat. After an empirical relaxation time, the time behavior for two entropies becomes different. While the classical entropy increases to the equilibrium entropy Seqm and stays there, its quantum analogue fluctuates incessantly around a mean overlineSɛ which is less than Seqm. We regard the entropy difference ΔS = S eqm - overlineSɛ as a measure of nonergodicity of the quantum motion of strongly chaotic systems and investigate its dependence on the Planck constant h. For fixed initial phase-space distributions, numerical results suggest that there is a scaling law ΔSαhβ with β ≈ 0.72 in the semiclassical regime.
Particle Production in Strong Electromagnetic Fields in Relativistic Heavy-Ion Collisions
Directory of Open Access Journals (Sweden)
Kirill Tuchin
2013-01-01
Full Text Available I review the origin and properties of electromagnetic fields produced in heavy-ion collisions. The field strength immediately after a collision is proportional to the collision energy and reaches ~mπ2 at RHIC and ~10mπ2 at LHC. I demonstrate by explicit analytical calculation that after dropping by about one-two orders of magnitude during the first fm/c of plasma expansion, it freezes out and lasts for as long as quark-gluon plasma lives as a consequence of finite electrical conductivity of the plasma. Magnetic field breaks spherical symmetry in the direction perpendicular to the reaction plane, and therefore all kinetic coefficients are anisotropic. I examine viscosity of QGP and show that magnetic field induces azimuthal anisotropy on plasma flow even in spherically symmetric geometry. Very strong electromagnetic field has an important impact on particle production. I discuss the problem of energy loss and polarization of fast fermions due to synchrotron radiation, consider photon decay induced by magnetic field, elucidate J/ψ dissociation via Lorentz ionization mechanism, and examine electromagnetic radiation by plasma. I conclude that all processes in QGP are affected by strong electromagnetic field and call for experimental investigation.
Non-Abelian Yang-Mills analogue of classical electromagnetic duality
International Nuclear Information System (INIS)
Chan, Hong-Mo; Faridani, J.; Tsun, T.S.
1995-01-01
The classic question of non-Abelian Yang-Mills analogue to electromagnetic duality is examined here in a minimalist fashion at the strictly four-dimensional, classical field, and point charge level. A generalization of the Abelian Hodge star duality is found which, though not yet known to give dual symmetry, reproduces analogues to many dual properties of the Abelian theory. For example, there is a dual potential, but it is a two-indexed tensor T μν of the Freedman-Townsend-type. Though not itself functioning as such, T μν gives rise to a dual parallel transport A μ for the phase of the wave function of the color magnetic charge, this last being a monopole of the Yang-Mills field but a source of the dual field. The standard color (electric) charge itself is found to be a monpole of A μ . At the same time, the gauge symmetry is found doubled from say SU(N) to SU(N)xSU(N). A novel feature is that all equations of motion, including the standard Yang-Mills and Wong equations, are here derived from a ''universal'' principle, namely, the Wu-Yang criterion for monpoles, where interactions arise purely as a consequence of the topological definition of the monopole charge. The technique used is the loop space formulation of Polyakov
Time profile of harmonics generated by a single atom in a strong electromagnetic field
International Nuclear Information System (INIS)
Antoine, P.; Piraux, B.; Maquet, A.
1995-01-01
We show that the time profile of the harmonics emitted by a single atom exposed to a strong electromagnetic field may be obtained through a wavelet or a Gabor analysis of the acceleration of the atomic dipole. This analysis is extremely sensitive to the details of the dynamics and sheds some light on the competition between the atomic excitation or ionization processes and photon emission. For illustration we study the interaction of atomic hydrogen with an intense laser pulse
International Nuclear Information System (INIS)
Chaturvedi, D.K.; Senatore, G.; Tosi, M.P.
1980-10-01
An analytic theory is presented for the static structure factor of the one-component classical plasma at strong couplings. The theory combines the hard-core model of Gillan for short-range correlations in the Coulomb fluid with a semiempirical representation of intermediate-range correlations, through which the requirement of thermodynamic consistency on the ''compressibility'' and the known equation of state of the system are satisfied. Excellent agreement is found with the available computer simulation data on the structure of the fluid. The approach becomes inapplicable at intermediate and weak couplings where effects of penetration in the Coulomb hole of each particle become important. (author)
International Nuclear Information System (INIS)
Bulanov, S.V.; Esirkepov, T.Zh.; Kamenets, F.F.; Naumova, N.M.
1995-01-01
The paper presents the results of a numeric modelling of the propagation of ultra short relativistically strong laser pulses in a rarefied plasma by the 'particle in cell'. Primary attention is paid to the process of the formation of electromagnetic solitons which can not be described in the approximation of envelopes. It is found that under certain conditions a significant portion of pulse energy can transform is solitons. The soliton excitation mechanism is related to a decrease of local frequency of electromagnetic radiation due to the generation of wave plasma waves. From one soliton to a stub of solitons can be generated in the wake of a relatively long pulse depending on the parameters of laser pulse in plasma. Particles are effectively accelerated forwards radiation propagation in the electric field of wake plasma waves. 22 refs., 7 figs
Directory of Open Access Journals (Sweden)
Igor V. Uporov
2015-09-01
Full Text Available The dipole interaction model is a classical electromagnetic theory for calculating circular dichroism (CD resulting from the π-π* transitions of amides. The theoretical model, pioneered by J. Applequist, is assembled into a package, DInaMo, written in Fortran allowing for treatment of proteins. DInaMo reads Protein Data Bank formatted files of structures generated by molecular mechanics or reconstructed secondary structures. Crystal structures cannot be used directly with DInaMo; they either need to be rebuilt with idealized bond angles and lengths, or they need to be energy minimized to adjust bond lengths and bond angles because it is common for crystal structure geometries to have slightly short bond lengths, and DInaMo is sensitive to this. DInaMo reduces all the amide chromophores to points with anisotropic polarizability and all nonchromophoric aliphatic atoms including hydrogens to points with isotropic polarizability; all other atoms are ignored. By determining the interactions among the chromophoric and nonchromophoric parts of the molecule using empirically derived polarizabilities, the rotational and dipole strengths are determined leading to the calculation of CD. Furthermore, ignoring hydrogens bound to methyl groups is initially explored and proves to be a good approximation. Theoretical calculations on 24 proteins agree with experiment showing bands with similar morphology and maxima.
International Nuclear Information System (INIS)
Galilo, Bogdan V.; Nedelko, Sergei N.
2011-01-01
The one-loop quark contribution to the QCD effective potential for the homogeneous Abelian gluon field in the presence of an external strong electromagnetic field is evaluated. The structure of extrema of the potential as a function of the angles between chromoelectric, chromomagnetic, and electromagnetic fields is analyzed. In this setup, the electromagnetic field is considered as an external one while the gluon field represents domain structured nonperturbative gluon configurations related to the QCD vacuum in the confinement phase. Two particularly interesting gluon configurations, (anti-)self-dual and crossed orthogonal chromomagnetic and chromoelectric fields, are discussed specifically. Within this simplified framework it is shown that the strong electromagnetic fields can play a catalyzing role for a deconfinement transition. At the qualitative level, the present consideration can be seen as a highly simplified study of an impact of the electromagnetic fields generated in relativistic heavy ion collisions on the strongly interacting hadronic matter.
Three-dimensional electromagnetic strong turbulence. I. Scalings, spectra, and field statistics
International Nuclear Information System (INIS)
Graham, D. B.; Robinson, P. A.; Cairns, Iver H.; Skjaeraasen, O.
2011-01-01
The first fully three-dimensional (3D) simulations of large-scale electromagnetic strong turbulence (EMST) are performed by numerically solving the electromagnetic Zakharov equations for electron thermal speeds ν e with ν e /c≥0.025. The results of these simulations are presented, focusing on scaling behavior, energy density spectra, and field statistics of the Langmuir (longitudinal) and transverse components of the electric fields during steady-state strong turbulence, where multiple wave packets collapse simultaneously and the system is approximately statistically steady in time. It is shown that for ν e /c > or approx. 0.17 strong turbulence is approximately electrostatic and can be explained using the electrostatic two-component model. For v e /c > or approx. 0.17 the power-law behaviors of the scalings, spectra, and field statistics differ from the electrostatic predictions and results because ν e /c is sufficiently high to allow transverse modes to become trapped in density wells. The results are compared with those of past 3D electrostatic strong turbulence (ESST) simulations and 2D EMST simulations. For number density perturbations, the scaling behavior, spectra, and field statistics are shown to be only weakly dependent on ν e /c, whereas the Langmuir and transverse scalings, spectra, and field statistics are shown to be strongly dependent on ν e /c. Three-dimensional EMST is shown to have features in common with 2D EMST, such as a two-component structure and trapping of transverse modes which are dependent on ν e /c.
Multipole Theory in Electromagnetism: Classical, Quantum and Symmetry Aspects, with Applications
Energy Technology Data Exchange (ETDEWEB)
Sihvola, Ari [Helsinki University of Technology (Finland)
2005-03-11
everything seems to work well with the 'old' multipole theory. But then the focus is shifted to observables associated with the reflection of waves from a surface. And there the classical analysis fails. This gives the motivation for the following chapters where the transformed multipole theory is represented. As expected, the correct multipole balance restores the physicality of the results in the reflection problem. One of the healthy reminders for an electrical engineer-scientist reading the book is the fact that E and B are the primary electric and magnetic fields. The other two field quantities, D and H, are the response fields (which, by the way, are also shown to be origin-dependent and poorly defined in the framework of classical multipole theory). In defence, however, for these poor latter quantities one can mention the many advantages of the engineering-type constitutive relations where D and B are expressed as responses to E and H. An example is the beautiful symmetry and complete analogy between the electric and magnetic quantities (voltage becomes current and vice versa in the duality transformation) which helps us write down solutions to electromagnetic problems from other known cases. From a pragmatic point of view we would also favour the use of quantities like Poynting vector and energy density (which require the H field). Another discussion-provoking question to the authors of the book might be whether their new multipole balance could be broken in the analysis of artificial materials. New nanotechnological discoveries and devices make it look like engineers can do anything. Perhaps in the design of complex media and metamaterials, a hot topic in today?s materials science, such macroscopic responses can be tailored where a certain high-order multipole contribution dominates over other, more basic ones. Multiple Theory in Electromagnetism is suitable for a broad spectrum of readers: solid-state physicists, molecular chemists, theoretical and
Sihvola, Ari
2005-03-01
' multipole theory. But then the focus is shifted to observables associated with the reflection of waves from a surface. And there the classical analysis fails. This gives the motivation for the following chapters where the transformed multipole theory is represented. As expected, the correct multipole balance restores the physicality of the results in the reflection problem. One of the healthy reminders for an electrical engineer-scientist reading the book is the fact that E and B are the primary electric and magnetic fields. The other two field quantities, D and H, are the response fields (which, by the way, are also shown to be origin-dependent and poorly\\endcolumn defined in the framework of classical multipole theory). In defence, however, for these poor latter quantities one can mention the many advantages of the engineering-type constitutive relations where D and B are expressed as responses to E and H. An example is the beautiful symmetry and complete analogy between the electric and magnetic quantities (voltage becomes current and vice versa in the duality transformation) which helps us write down solutions to electromagnetic problems from other known cases. From a pragmatic point of view we would also favour the use of quantities like Poynting vector and energy density (which require the H field). Another discussion-provoking question to the authors of the book might be whether their new multipole balance could be broken in the analysis of artificial materials. New nanotechnological discoveries and devices make it look like engineers can do anything. Perhaps in the design of complex media and metamaterials, a hot topic in todayÂ's materials science, such macroscopic responses can be tailored where a certain high-order multipole contribution dominates over other, more basic ones. Multiple Theory in Electromagnetism is suitable for a broad spectrum of readers: solid-state physicists, molecular chemists, theoretical and experimental optics scientists, radiophysics
Multipole Theory in Electromagnetism: Classical, Quantum and Symmetry Aspects, with Applications
International Nuclear Information System (INIS)
Sihvola, Ari
2005-01-01
' multipole theory. But then the focus is shifted to observables associated with the reflection of waves from a surface. And there the classical analysis fails. This gives the motivation for the following chapters where the transformed multipole theory is represented. As expected, the correct multipole balance restores the physicality of the results in the reflection problem. One of the healthy reminders for an electrical engineer-scientist reading the book is the fact that E and B are the primary electric and magnetic fields. The other two field quantities, D and H, are the response fields (which, by the way, are also shown to be origin-dependent and poorly defined in the framework of classical multipole theory). In defence, however, for these poor latter quantities one can mention the many advantages of the engineering-type constitutive relations where D and B are expressed as responses to E and H. An example is the beautiful symmetry and complete analogy between the electric and magnetic quantities (voltage becomes current and vice versa in the duality transformation) which helps us write down solutions to electromagnetic problems from other known cases. From a pragmatic point of view we would also favour the use of quantities like Poynting vector and energy density (which require the H field). Another discussion-provoking question to the authors of the book might be whether their new multipole balance could be broken in the analysis of artificial materials. New nanotechnological discoveries and devices make it look like engineers can do anything. Perhaps in the design of complex media and metamaterials, a hot topic in today?s materials science, such macroscopic responses can be tailored where a certain high-order multipole contribution dominates over other, more basic ones. Multiple Theory in Electromagnetism is suitable for a broad spectrum of readers: solid-state physicists, molecular chemists, theoretical and experimental optics scientists, radiophysics experts
Chiral symmetry and quark-antiquark pair creation in a strong color-electromagnetic field
International Nuclear Information System (INIS)
Suganuma, Hideo; Tatsumi, Toshitaka.
1993-01-01
We study the manifestation of chiral symmetry and q-q-bar pair creation in the presence of the external color-electromagnetic field, using the Nambu-Jona-Lasinio model. We derive the compact formulae of the effective potential, the Dyson equation for the dynamical quark mass and the q-q-bar pair creation rate in the covariantly constant color-electromagnetic field. Our results are compared with those in other approaches. The chiral-symmetry restoration takes place by a strong color-electric field, and the rapid reduction of the dynamical quark mass is found around the critical field strength, ε cr ≅4GeV/fm. Natural extension to the three-flavor case including s-quarks is also done. Around quarks or antiquarks, chiral symmetry would be restored by the sufficiently strong color-electric field, which may lead to the chiral bag picture of hadrons. For the early stage for ultrarelativistic heavy-ion collisions, the possibility of the chiral-symmetry restoration is indicated in the central region just after the collisions. (author)
Interference effects at photoionization of Rydberg atoms by a strong electromagnetic field
International Nuclear Information System (INIS)
Movsesyan, A.M.; Fedorov, M.V.
1989-01-01
The photoionization of Rydberg atoms in a strong electromagnetic field is considered. Degeneration of the levels with respect to the orbital moment, their Stark splitting and the possibility of resonant interaction with levels of lower energy are taken into account. The complex quasi-energies of the system, photoelectron spectrum in the limit of an infinite duration of interaction and the time dependence of the total ionization probability are found. It is shown that a narrowing of the quasi-energy levels occurs in a strong field. Against a background of the quasi- continuum the quasi-energy spectrum consists of more or less narrow levels. In this case the photoelectron spectrum acquires a multi-peak form. With increasing field strength the height of the peaks increases, whereas their width decreases. The ionization rate decreases with increasing field strength. The presence of a quasi-continuum is the cause of the partially non-exponential nature of the atomic disintegration
International Nuclear Information System (INIS)
Drechsler, W.
1977-01-01
A Lagrangian formalism invariant under the gauge group U 1 xUSpsub(2.2) is set up in terms of spinor fields defined on a fiber bundle with Cartan connexion. The fiber of the Cartan bundle over space-time associated with strong interactions is characterized by an elementary length parameter R related to the range of the strong forces, and the structural group USpsub(2.2) of the bundle (being the covering group of the SOsub(4.1) de Sitter group) implies a gauge description of strong interactions based on the noncompact gauge group USpsub(2.2). The U 1 factor in the total gauge group corresponds to the usual gauge formulation for the electromagnetic interactions. The positivity of the energy associated with stable extended one-particle states in this dualistic description of charged hadronic matter immersed in the fiber geometry (this dualism is called strong fiber dynamics (SFD)) requires hadrons to be assigned to representations of the compact subgroup SU 2 xSU 2 of the strong-interaction gauge group USpsub(2.2). A brief discussion of the point-particle limit R→O is given by linking the presented SFD formalism for extended hadrons to an idealized description in terms of operators in a local quantum field theory
Indian Academy of Sciences (India)
2013-11-11
Nov 11, 2013 ... Polanyi's classic paper, co-authored by Henry Eyring, reproduced in this ... spatial conf guration of the atoms in terms of the energy function of the diatomic .... The present communication deals with the construction of such .... These three contributions are complemented by a fourth term if one takes into.
Introduction to gauge theories of the strong, weak, and electromagnetic interactions
International Nuclear Information System (INIS)
Quigg, C.
1980-07-01
The plan of these notes is as follows. Chapter 1 is devoted to a brief evocative review of current beliefs and prejudices that form the context for the discussion to follow. The idea of Gauge Invariance is introduced in Chapter 2, and the connection between conservation laws and symmetries of the Lagrangian is recalled. Non-Abelian gauge field theories are constructed in Chapter 3, by analogy with the familiar case of electromagnetism. The Yang-Mills theory based upon isospin symmetry is constructed explicitly, and the generalization is made to other gauge groups. Chapter 4 is concerned with spontaneous symmetry breaking and the phenomena that occur in the presence or absence of local gauge symmetries. The existence of massless scalar fields (Goldstone particles) and their metamorphosis by means of the Higgs mechanism are illustrated by simple examples. The Weinberg-Salam model is presented in Chapter 5, and a brief resume of applications to experiment is given. Quantum Chromodynamics, the gauge theory of colored quarks and gluons, is developed in Chapter 6. Asymptotic freedom is derived schematically, and a few simple applications of perturbative QCD ae exhibited. Details of the conjectured confinement mechanism are omitted. The strategy of grand unified theories of the strong, weak, and electromagnetic interactions is laid out in Chapter 7. Some properties and consequences of the minimal unifying group SU(5) are presented, and the gauge hierarchy problem is introduced in passing. The final chapter contains an essay on the current outlook: aspirations, unanswered questions, and bold scenarios
Wang, Yun; Zhao, Min; Wang, Qingguo
2018-01-01
In order to measure the pulse shielding performance of materials with the characteristic of field-induced insulator-conductor phase transition when materials are used for electromagnetic shielding, a dynamic test method was proposed based on a coaxial fixture. Experiment system was built by square pulse source, coaxial cable, coaxial fixture, attenuator, and oscilloscope and insulating components. S11 parameter of the test system was obtained, which suggested that the working frequency ranges from 300 KHz to 7.36 GHz. Insulating performance is good enough to avoid discharge between conductors when material samples is exposed in the strong electromagnetic pulse field up to 831 kV/m. This method is suitable for materials with annular shape, certain thickness and the characteristic of field-induced insulator-conductor phase transition to get their shielding performances of strong electromagnetic pulse.
Introduction to unified theories of weak, electromagnetic and strong interactions - SU(5)
International Nuclear Information System (INIS)
Billoire, Alain; Morel, Andre.
1980-11-01
These notes correspond to a series of lectures given at Salay during winter 1979-1980. They are meant to be an introduction to the so-called grand unified theories of weak, electromagnetic and strong interactions. In a first part, we recall in a very elementary way the standard SU(2) model of electroweak interactions, putting the emphasis on the questions which are left open by this model and which unified theories help to answer. In part II, we explain in a systematic way how unified theories can be constructed, and develop the SU(5) model in great detail. Other models, like SO(10) and E 6 , are not presented, because SU(5) is the simplest one and has been subject to the deepest investigations up to now. Also it appears that most concepts and general results are not specific to any particular symmetry group [fr
Strongly first-order electroweak phase transition and classical scale invariance
Farzinnia, Arsham; Ren, Jing
2014-10-01
In this work, we examine the possibility of realizing a strongly first-order electroweak phase transition within the minimal classically scale-invariant extension of the standard model (SM), previously proposed and analyzed as a potential solution to the hierarchy problem. By introducing one complex gauge-singlet scalar and three (weak scale) right-handed Majorana neutrinos, the scenario was successfully rendered capable of achieving a radiative breaking of the electroweak symmetry (by means of the Coleman-Weinberg mechanism), inducing nonzero masses for the SM neutrinos (via the seesaw mechanism), presenting a pseudoscalar dark matter candidate (protected by the CP symmetry of the potential), and predicting the existence of a second CP-even boson (with suppressed couplings to the SM content) in addition to the 125 GeV scalar. In the present treatment, we construct the full finite-temperature one-loop effective potential of the model, including the resummed thermal daisy loops, and demonstrate that finite-temperature effects induce a first-order electroweak phase transition. Requiring the thermally driven first-order phase transition to be sufficiently strong at the onset of the bubble nucleation (corresponding to nucleation temperatures TN˜100-200 GeV) further constrains the model's parameter space; in particular, an O(0.01) fraction of the dark matter in the Universe may be simultaneously accommodated with a strongly first-order electroweak phase transition. Moreover, such a phase transition disfavors right-handed Majorana neutrino masses above several hundreds of GeV, confines the pseudoscalar dark matter masses to ˜1-2 TeV, predicts the mass of the second CP-even scalar to be ˜100-300 GeV, and requires the mixing angle between the CP-even components of the SM doublet and the complex singlet to lie within the range 0.2≲sinω ≲0.4. The obtained results are displayed in comprehensive exclusion plots, identifying the viable regions of the parameter space
A New Semi-Symmetric Uniﬁed Field Theory of the Classical Fields of Gravity and Electromagnetism
Directory of Open Access Journals (Sweden)
Suhendro I.
2007-10-01
Full Text Available We attempt to present a classical theoretical framework in which the gravitational and electromagnetic fields are unified as intrinsic geometric objects in the space-time manifold. For this purpose, we first present the preliminary geometric considerations dealing with the metric differential geometry of Cartan connections. The unified field theory is then developed as an extension of the general theory of relativity based on a semi- symmetric Cartan connection which is meant to be as close as possible structurally to the symmetric connection of the Einstein-Riemann space-time.
Directory of Open Access Journals (Sweden)
H. Korth
2005-06-01
Full Text Available We present a case study of a prolonged interval of strongly northward orientation of the interplanetary magnetic field on 16 July 2000, 16:00-19:00 UT to characterize the energy exchange between the magnetosphere and ionosphere for conditions associated with minimum solar wind-magnetosphere coupling. With reconnection occurring tailward of the cusp under northward IMF conditions, the reconnection dynamo should be separated from the viscous dynamo, presumably driven by the Kelvin-Helmholtz (KH instability. Thus, these conditions are also ideal for evaluating the contribution of a viscous interaction to the coupling process. We derive the two-dimensional distribution of the Poynting vector radial component in the northern sunlit polar ionosphere from magnetic field observations by the constellation of Iridium satellites together with drift meter and magnetometer observations from the Defense Meteorological Satellite Program (DMSP F13 and F15 satellites. The electromagnetic energy flux is then compared with the particle energy flux obtained from auroral images taken by the far-ultraviolet (FUV instrument on the Imager for Magnetopause to Aurora Global Exploration (IMAGE spacecraft. The electromagnetic energy input to the ionosphere of 51 GW calculated from the Iridium/DMSP observations is eight times larger than the 6 GW due to particle precipitation all poleward of 78° MLAT. This result indicates that the energy transport is significant, particularly as it is concentrated in a small region near the magnetic pole, even under conditions traditionally considered to be quiet and is dominated by the electromagnetic flux. We estimate the contributions of the high and mid-latitude dynamos to both the Birkeland currents and electric potentials finding that high-latitude reconnection accounts for 0.8 MA and 45kV while we attribute <0.2MA and ~5kV to an interaction at lower latitudes having the sense of a viscous interaction. Given that these
Autler-Townes effect in a strongly driven electromagnetically induced transparency resonance
International Nuclear Information System (INIS)
Yang Lijun; Zhang Lianshui; Li Xiaoli; Han Li; Fu Guangsheng; Manson, Neil B.; Suter, Dieter; Wei Changjiang
2005-01-01
In this paper we study the nonlinear behavior of an electromagnetically induced transparency (EIT) resonance subject to a coherent driving field. The EIT is associated with a Λ three-level system where two hyperfine levels within an electronic ground state are coupled to a common excited state level by a coupling field and a probe field. In addition there is an radio-frequency (rf) field driving a hyperfine transition within the ground state. The paper contrasts two different situations. In one case the rf-driven transition shares a common level with the probed transition and in the second case it shares a common level with the coupled transition. In both cases the EIT resonance is split into a doublet and the characteristics of the EIT doublet are determined by the strength and frequency of the rf-driving field. The doublet splitting originates from the rf-field induced dynamic Stark effect and has close analogy with the Autler-Townes effect observed in three-level pump-probe spectroscopy study. The situation changes when the rf field is strong and the two cases are very different. One is analogous to two Λ three-level systems with EIT resonance associated with each. The other corresponds to a doubly driven three-level system with rf-field-induced electromagnetically induced absorption resonance. The two situations are modeled using numerical solutions of the relevant equation of motion of density matrix. In addition a physical account of their behaviors is given in terms of a dressed state picture
Speed of Gravitational Waves from Strongly Lensed Gravitational Waves and Electromagnetic Signals.
Fan, Xi-Long; Liao, Kai; Biesiada, Marek; Piórkowska-Kurpas, Aleksandra; Zhu, Zong-Hong
2017-03-03
We propose a new model-independent measurement strategy for the propagation speed of gravitational waves (GWs) based on strongly lensed GWs and their electromagnetic (EM) counterparts. This can be done in two ways: by comparing arrival times of GWs and their EM counterparts and by comparing the time delays between images seen in GWs and their EM counterparts. The lensed GW-EM event is perhaps the best way to identify an EM counterpart. Conceptually, this method does not rely on any specific theory of massive gravitons or modified gravity. Its differential setting (i.e., measuring the difference between time delays in GW and EM domains) makes it robust against lens modeling details (photons and GWs travel in the same lensing potential) and against internal time delays between GW and EM emission acts. It requires, however, that the theory of gravity is metric and predicts gravitational lensing similar to general relativity. We expect that such a test will become possible in the era of third-generation gravitational-wave detectors, when about 10 lensed GW events would be observed each year. The power of this method is mainly limited by the timing accuracy of the EM counterpart, which for kilonovae is around 10^{4} s. This uncertainty can be suppressed by a factor of ∼10^{10}, if strongly lensed transients of much shorter duration associated with the GW event can be identified. Candidates for such short transients include short γ-ray bursts and fast radio bursts.
The Quantum-to-Classical Transition in Strongly Interacting Nanoscale Systems
Benatov, Latchezar Latchezarov
This thesis comprises two separate but related studies, dealing with two strongly interacting nanoscale systems on the border between the quantum and classical domains. In Part 1, we use a Born-Markov approximated master equation approach to study the symmetrized-in-frequency current noise spectrum and the oscillator steady state of a nanoelectromechanical system where a nanoscale resonator is coupled linearly via its momentum to a quantum point contact (QPC). Our current noise spectra exhibit clear signatures of the quantum correlations between the QPC current and the back-action force on the oscillator at a value of the relative tunneling phase where such correlations are expected to be maximized. We also show that the steady state of the oscillator obeys a classical Fokker-Planck equation, but can experience thermomechanical noise squeezing in the presence of a momentum-coupled detector bath and a position-coupled environmental bath. Besides, the full master equation clearly shows that half of the detector back-action is correlated with electron tunneling, indicating a departure from the model of the detector as an effective bath and suggesting that a future calculation valid at lower bias voltage, stronger tunneling and/or stronger coupling might reveal interesting quantum effects in the oscillator dynamics. In the second part of the thesis, we study the subsystem dynamics and thermalization of an oscillator-spin star model, where a nanomechanical resonator is coupled to a few two-level systems (TLS's). We use a fourth-order Runge-Kutta numerical algorithm to integrate the Schrodinger equation for the system and obtain our results. We find that the oscillator reaches a Boltzmann steady state when the TLS bath is initially in a thermal state at a temperature higher than the oscillator phonon energy. This occurs in both chaotic and integrable systems, and despite the small number of spins (only six) and the lack of couplings between them. At the same time, pure
Classical electromagnetic non-minimal coupling for spin 3/2 fields
International Nuclear Information System (INIS)
Villanueva, V. M.; Obregon, O.; Nieto, J. A.
1996-01-01
We obtain a non-minimal electromagnetic coupling for spin 3/2 particles from linearized N=2 Supergravity. This coupling coincides with the one found by Ferrara et al. by demanding g=2 at the tree level. Linearized Einstein field equations plus interaction terms are obtained by squaring the Rarita-Schwinger with this non-minimal coupling by using generalized Poisson brackets
International Nuclear Information System (INIS)
Goodman, S.
1993-05-01
Optical pumping of the ionospheric plasma by high-frequency radio waves produces a state of turbulence. Several consequences of the pumping are considered in this thesis. At reflection altitude the plasma is thought to be dominated by parametric instabilities and strong turbulence; these are both encapsulated in the so called Zakharov equations. The Zakharov equations are derived and generalised from kinetic theory. Limits of validity, corrections to the ion sound speed,effective ponderomotive force, nonlinear damping and other generalisation are included. As an example of the difference a kinetic approach makes, the threshold for parametric instabilities is seen to be lowered in a kinetic plasma. Mostly relevant to the upper hybrid layer is the recent discovery in the pumping experiments of stimulated electromagnetic emissions (SEE). In particular one feature of SEE which occurs around the cyclotron harmonics and depends on density striations is investigated. The observed frequency of emission, dependency on striations, time evolution and cutoff frequency below which the feature does not occur, are explained. Two theoretical approaches are taken. The first is a parametric three wave decay instability followed by a nonlinear mixing to produce SEE. Thresholds for the instability are well within experimental capacity. The second, less orthodox, approach, is a finite amplitude model. The finite amplitude model goes beyond the traditional parametric approach by being able to predict radiated power output. Miscellaneous aspects of a turbulent ionosphere are also examined. The dependency of the scattering cross section of a turbulent plasma upon higher order perturbations is considered. In a turbulent plasma, density gradients steeper than characteristic plasma scales may develop. The case of calculating the dielectric permittivity for a linear gradient of arbitrary steepness is considered
Effects of strong and electromagnetic correlations on neutrino interactions in dense matter
International Nuclear Information System (INIS)
Reddy, S.; Prakash, M.; Lattimer, J.M.; Reddy, S.; Pons, J.A.
1999-01-01
An extensive study of the effects of correlations on both charged and neutral current weak interaction rates in dense matter is performed. Both strong and electromagnetic correlations are considered. The propagation of particle-hole interactions in the medium plays an important role in determining the neutrino mean free paths. The effects due to Pauli blocking and density, spin, and isospin correlations in the medium significantly reduce the neutrino cross sections. As a result of the lack of experimental information at high density, these correlations are necessarily model dependent. For example, spin correlations in nonrelativistic models are found to lead to larger suppressions of neutrino cross sections compared to those of relativistic models. This is due to the tendency of the nonrelativistic models to develop spin instabilities. Notwithstanding the above caveats, and the differences between nonrelativistic and relativistic approaches such as the spin- and isospin-dependent interactions and the nucleon effective masses, suppressions of order 2 - 3, relative to the case in which correlations are ignored, are obtained. Neutrino interactions in dense matter are especially important for supernova and early neutron star evolution calculations. The effects of correlations for protoneutron star evolution are calculated. Large effects on the internal thermodynamic properties of protoneutron stars, such as the temperature, are found. These translate into significant early enhancements in the emitted neutrino energies and fluxes, especially after a few seconds. At late times, beyond about 10 s, the emitted neutrino fluxes decrease more rapidly compared to simulations without the effects of correlations, due to the more rapid onset of neutrino transparency in the protoneutron star. copyright 1999 The American Physical Society
International Nuclear Information System (INIS)
Belvedere, Riccardo; Pugliese, Daniela; Rueda, Jorge A.; Ruffini, Remo; Xue, She-Sheng
2012-01-01
We formulate the equations of equilibrium of neutron stars taking into account strong, weak, electromagnetic, and gravitational interactions within the framework of general relativity. The nuclear interactions are described by the exchange of the σ, ω, and ρ virtual mesons. The equilibrium conditions are given by our recently developed theoretical framework based on the Einstein–Maxwell–Thomas–Fermi equations along with the constancy of the general relativistic Fermi energies of particles, the “Klein potentials”, throughout the configuration. The equations are solved numerically in the case of zero temperatures and for selected parameterizations of the nuclear models. The solutions lead to a new structure of the star: a positively charged core at supranuclear densities surrounded by an electronic distribution of thickness ∼ℏ/(m e c)∼10 2 ℏ/(m π c) of opposite charge, as well as a neutral crust at lower densities. Inside the core there is a Coulomb potential well of depth ∼m π c 2 /e. The constancy of the Klein potentials in the transition from the core to the crust, imposes the presence of an overcritical electric field ∼(m π /m e ) 2 E c , the critical field being E c =m e 2 c 3 /(eℏ). The electron chemical potential and the density decrease, in the boundary interface, until values μ e crust e core and ρ crust core . For each central density, an entire family of core–crust interface boundaries and, correspondingly, an entire family of crusts with different mass and thickness, exist. The configuration with ρ crust =ρ drip ∼4.3×10 11 gcm −3 separates neutron stars with and without inner crust. We present here the novel neutron star mass–radius for the especial case ρ crust =ρ drip and compare and contrast it with the one obtained from the traditional Tolman–Oppenheimer–Volkoff treatment.
Sater, Julien
The theory of Artificial Boundary Conditions described by Antoine et al. [2,4-6] for the Schrodinger equation is applied to the Klein-Gordon (KG) in two-dimensions (2-D) for spinless particles subject to electromagnetic fields. We begin by providing definitions for a basic understanding of the theory of operators, differential geometry and wave front sets needed to discuss the factorization theorem thanks to Nirenberg and Hormander [14, 16]. The laser-free Klein-Gordon equation in 1-D is then discussed, followed by the case including electrodynamics potentials, concluding with the KG equation in 2-D space with electrodynamics potentials. We then consider numerical simulations of the laser-particle KG equation, which includes a brief analysis of a finite difference scheme. The conclusion integrates a discussion of the numerical results, the successful completion of the objective set forth, a declaration of the unanswered encountered questions and a suggestion of subjects for further research.
Quantum and classical strong direct product theorems and optimal time-space tradeoffs
H. Klauck (Hartmut); R. Spalek (Robert); R. M. de Wolf (Ronald)
2007-01-01
textabstractA strong direct product theorem says that if we want to compute $k$ independent instances of a function, using less than $k$ times the resources needed for one instance, then our overall success probability will be exponentially small in $k$. We establish such theorems for the
International Nuclear Information System (INIS)
Mota, R D; Xicotencatl, M A; Granados, V D
2004-01-01
In this work we introduce a generalization of the Jauch and Rohrlich quantum Stokes operators when the arrival direction from the source is unknown a priori. We define the generalized Stokes operators as the Jordan-Schwinger map of a triplet of harmonic oscillators with the Gell-Mann and Ne'eman matrices of the SU(3) symmetry group. We show that the elements of the Jordan-Schwinger map are the constants of motion of the three-dimensional isotropic harmonic oscillator. Also, we show that the generalized Stokes operators together with the Gell-Mann and Ne'eman matrices may be used to expand the polarization matrix. By taking the expectation value of the Stokes operators in a three-mode coherent state of the electromagnetic field, we obtain the corresponding generalized classical Stokes parameters. Finally, by means of the constants of motion of the classical 3D isotropic harmonic oscillator we describe the geometrical properties of the polarization ellipse
Mota, R. D.; Xicoténcatl, M. A.; Granados, V. D.
2004-02-01
In this work we introduce a generalization of the Jauch and Rohrlich quantum Stokes operators when the arrival direction from the source is unknown a priori. We define the generalized Stokes operators as the Jordan-Schwinger map of a triplet of harmonic oscillators with the Gell-Mann and Ne'eman matrices of the SU(3) symmetry group. We show that the elements of the Jordan-Schwinger map are the constants of motion of the three-dimensional isotropic harmonic oscillator. Also, we show that the generalized Stokes operators together with the Gell-Mann and Ne'eman matrices may be used to expand the polarization matrix. By taking the expectation value of the Stokes operators in a three-mode coherent state of the electromagnetic field, we obtain the corresponding generalized classical Stokes parameters. Finally, by means of the constants of motion of the classical 3D isotropic harmonic oscillator we describe the geometrical properties of the polarization ellipse.
Energy Technology Data Exchange (ETDEWEB)
Mota, R D [Unidad Profesional Interdisciplinaria de IngenierIa y TecnologIas Avanzadas, IPN. Av. Instituto Politecnico Nacional 2580, Col. La Laguna Ticoman, 07340 Mexico DF (Mexico); Xicotencatl, M A [Departamento de Matematicas del Centro de Investigacion y Estudios Avanzados del IPN, Mexico DF, 07000 (Mexico); Granados, V D [Escuela Superior de FIsica y Matematicas, Instituto Politecnico Nacional, Ed. 9, Unidad Profesional Adolfo Lopez Mateos, 07738 Mexico DF (Mexico)
2004-02-20
In this work we introduce a generalization of the Jauch and Rohrlich quantum Stokes operators when the arrival direction from the source is unknown a priori. We define the generalized Stokes operators as the Jordan-Schwinger map of a triplet of harmonic oscillators with the Gell-Mann and Ne'eman matrices of the SU(3) symmetry group. We show that the elements of the Jordan-Schwinger map are the constants of motion of the three-dimensional isotropic harmonic oscillator. Also, we show that the generalized Stokes operators together with the Gell-Mann and Ne'eman matrices may be used to expand the polarization matrix. By taking the expectation value of the Stokes operators in a three-mode coherent state of the electromagnetic field, we obtain the corresponding generalized classical Stokes parameters. Finally, by means of the constants of motion of the classical 3D isotropic harmonic oscillator we describe the geometrical properties of the polarization ellipse.
Probing non nucleonic degrees of freedom with strong and electromagnetic interactions
International Nuclear Information System (INIS)
Frois, B.
1985-10-01
In this talk, I would like to examine our present view on non-nucleonic degrees of freedom with a few typical experimental results obtained recently both with hadronic and electromagnetic probes at intermediate energies. It is the first generation of experimental data which has probed mesonic degrees of freedom with a spatial resolution of the order of 0.5 fm. This has made possible for example the measurement of the size of the pion-nucleon interaction region. This is very stimulating progress and we begin to have a coherent overview on the various reaction mechanisms which are induced by hadronic and electromagnetic probes
1981-02-01
UNIVERSITY OF MARYLAND DEPARTMENT OF PHYSICS 4WJD ASTRONOMY COLLG PAM A 2 3i 81 4 30) 235. RADIATION FROM A .ELATIVISTIC_§LECTRON BEAM IN AZOLECULAR...A MOLECULAR MEDIUM DUE TO PARAMETRIC PUMPING BY A STRONG ELECTROMAGNETIC WAVE L. Stenflo Department of Plasma Physics Umel University S-90187 Umel...GUteborg, Sweden and Laboratory for Plasma and Fusion Energy Studies University of Maryland College Park, Maryland 20742 Physics Publication Number 81
Classical anomalous absorption in strongly magnetized plasmas and effective shielding length
International Nuclear Information System (INIS)
Matsuda, K.
1981-01-01
The high-frequency conductivity tensor of a plasma in a magnetic field has been evaluated. An anomalous perpendicular conductivity is obtained for a strongly magnetized plasma. Contrarily to the previous prediction, the effective shielding length is found to be the Debye length even when the Debye length is larger than the electron gyroradius. The effective shielding length is further discussed by presenting the generalized Balescu-Lenard equation
International Nuclear Information System (INIS)
Konstantinovich, A.V.; Melnychuk, S.V.; Konstantinovich, I.A.
2002-01-01
The integral expressions for spectral-angular and spectral distributions of the radiation power of heterogeneous charged particles system moving on arbitrary trajectory in nonabsorbable isotropic media media with ε≠1 , μ≠1 are obtained using the Lorentz's self-interaction method. In this method a proper electromagnetic field, acting on electron, is defined as a semi difference between retarded and advanced potentials (Dirac, 1938). The power spectrum of Cherenkov radiation for the linear uniformly moving heterogeneous system of charged particles are obtained. It is found that the expression for the radiation power of heterogeneous system of charged particles becomes simplified when a system of charged particles is homogeneous. In this case the radiation power includes the coherent factor. It is shown what the redistribution effects in energy of the radiation spectrum of the studied system are caused by the coherent factor. The radiation spectrum of the system of electrons moving in a circle in this medium is discrete. The Doppler effect causes the appearance of the new harmonics for the system of electrons moving in a spiral. These harmonics form the region of continuous radiation spectrum. (authors)
International Nuclear Information System (INIS)
Presnyakov, L.P.; Uskov, D.B.
1997-01-01
The nonstationary theory of double ionization of two-electron atoms in collisions with multicharged ions or under the impact of intensive electromagnetic field is developed. The approach, making it possible to study both problems by uniform method, is formulated. The two-electron wave function of continuous spectrum, accounting for interaction of electrons with atomic nucleus, external ionizer and between themselves is obtained. The calculation results on the helium atoms double ionization by multicharged ions is a good quantitative agreement with available experimental data
Ionization of a two-electron atom in a strong electromagnetic field
International Nuclear Information System (INIS)
Ovodova, O.V.; Popov, A.M.; Tikhonova, O.V.
1997-01-01
A one-dimensional model of a helium atom in an intense field of a femtosecond electromagnetic pulse has been constructed using the Hartree technique. 'Exact' calculations have been compared to the approximations of 'frozen' and 'passive' electrons. A nonmonotonic dependence of the single-electron ionization probability on the radiation intensity has been detected. Minima in the ionization probability are due to multiphoton resonances between different atomic states due to the dynamic Stark effect. We suggest that the ionization suppression is due to the interference stabilization in this case
Particle physics in intense electromagnetic fields
International Nuclear Information System (INIS)
Kurilin, A.V.
1999-01-01
The quantum field theory in the presence of classical background electromagnetic field is reviewed giving a pedagogical introduction to the Feynman-Furry method of describing non-perturbative interactions with very strong electromagnetic fields. A particular emphasis is given to the case of the plane-wave electromagnetic field for which the charged particles' wave functions and propagators are presented. Some general features of quantum processes proceeding in the intense electromagnetic background are argued. The possibilities of searching new physics through the investigations of quantum phenomena induced by a strong electromagnetic environment are also discussed
Energy Technology Data Exchange (ETDEWEB)
Eminov, P.A., E-mail: peminov@mail.ru [Moscow State University of Instrument Engineering and Computer Sciences, 20 Stromynka Street, Moscow 2107996 (Russian Federation); National Research University Higher School of Economics, 3/12 Bolshoy Trekhsvyatskiy pereulok, Moscow 109028 (Russian Federation)
2013-10-01
Ionization processes for a two dimensional quantum dot subjected to combined electrostatic and alternating electric fields of the same direction are studied using quantum mechanical methods. We derive analytical equations for the ionization probability in dependence on characteristic parameters of the system for both extreme cases of a constant electric field and of a linearly polarized electromagnetic wave. The ionization probabilities for a superposition of dc and low frequency ac electric fields of the same direction are calculated. The impulse distribution of ionization probability for a system bound by short range forces is found for a superposition of constant and alternating fields. The total probability for this process per unit of time is derived within exponential accuracy. For the first time the influence of alternating electric field on electron tunneling probability induced by an electrostatic field is studied taking into account the pre-exponential term.
Jin, Shouwen; Wang, Daqi
2014-05-01
Eight crystalline organic acid-base adducts derived from alkane bridged bis(N-benzimidazole) and organic acids (2,4,6-trinitrophenol, p-nitrobenzoic acid, m-nitrobenzoic acid, 3,5-dinitrobenzoic acid, 5-sulfosalicylic acid and oxalic acid) were prepared and characterized by X-ray diffraction analysis, IR, mp, and elemental analysis. Of the eight compounds five are organic salts (1, 4, 6, 7 and 8) and the other three (2, 3, and 5) are cocrystals. In all of the adducts except 1 and 8, the ratio of the acid and the base is 2:1. All eight supramolecular assemblies involve extensive intermolecular classical hydrogen bonds as well as other noncovalent interactions. The role of weak and strong noncovalent interactions in the crystal packing is ascertained. These weak interactions combined, all the complexes displayed 3D framework structure. The results presented herein indicate that the strength and directionality of the classical N+-H⋯O-, O-H⋯O, and O-H⋯N hydrogen bonds (ionic or neutral) and other nonbonding associations between acids and ditopic benzimidazoles are sufficient to bring about the formation of cocrystals or organic salts.
Grant, Ian S
1990-01-01
The Manchester Physics Series General Editors: D. J. Sandiford; F. Mandl; A. C. Phillips Department of Physics and Astronomy, University of Manchester Properties of Matter B. H. Flowers and E. Mendoza Optics Second Edition F. G. Smith and J. H. Thomson Statistical Physics Second Edition F. Mandl Electromagnetism Second Edition I. S. Grant and W. R. Phillips Statistics R. J. Barlow Solid State Physics Second Edition J. R. Hook and H. E. Hall Quantum Mechanics F. Mandl Particle Physics Second Edition B. R. Martin and G. Shaw the Physics of Stars Second Edition A. C. Phillips Computing for Scient
International Nuclear Information System (INIS)
Arnold, R.C.
1975-12-01
A systematic calculus of long-range Regge cut effects in multiparticle production is constructed in the form of an infrared-divergent stochastic field theory. Total cross sections and two-body overlap integrals in such a theory may depend very sensitively upon internal quantum-numbers of incident particles, resulting in a strong symmetry breaking at ultra-high energies. Such symmetry violations will influence low energy processes through dispersion relations, and a bootstrap of weak interactions becomes possible. A rough analytic estimate of the scale of thresholds for such effects yields a BCS-type gap equation, which expresses the scale of weak and electromagnetic couplings in terms of purely strong-interaction parameters
International Nuclear Information System (INIS)
Freiv, A V; Roshchupkin, S P
2008-01-01
The possibility of amplification of electromagnetic radiation is theoretically studied in the scattering of a quasi-classical electron by an ion in a field of linearly polarized waves of medium intensity. An expression for the total cross-section (the gain coefficient) for the wide interval of values of the adiabaticity parameter is obtained. It is shown that the wave amplification takes place in the range of values of adiabaticity parameter greater than 2 and can be sufficiently large
Liang, Caiyun; Wang, Zhenfeng; Wu, Lina; Zhang, Xiaochen; Wang, Huan; Wang, Zhijiang
2017-09-06
A novel light but strong SiC foam with hierarchical porous architecture was fabricated by using dough as raw material via carbonization followed by carbothermal reduction with silicon source. A significant synergistic effect is achieved by embedding meso- and nanopores in a microsized porous skeleton, which endows the SiC foam with high-performance electromagnetic interference (EMI) shielding, thermal insulation, and mechanical properties. The microsized skeleton withstands high stress. The meso- and nanosized pores enhance multiple reflection of the incident electromagnetic waves and elongate the path of heat transfer. For the hierarchical porous SiC foam with 72.8% porosity, EMI shielding can be higher than 20 dB, and specific EMI effectiveness exceeds 24.8 dB·cm 3 ·g -1 at a frequency of 11 GHz at 25-600 °C, which is 3 times higher than that of dense SiC ceramic. The thermal conductivity reaches as low as 0.02 W·m -1 ·K -1 , which is comparable to that of aerogel. The compressive strength is as high as 9.8 MPa. Given the chemical and high-temperature stability of SiC, the fabricated SiC foam is a promising candidate for modern aircraft and automobile applications.
Energy Technology Data Exchange (ETDEWEB)
Arsenyev, S. A.; Koryagin, S. A., E-mail: koryagin@appl.sci-nnov.ru [Russian Academy of Sciences, Institute of Applied Physics (Russian Federation)
2012-06-15
A classical analysis is presented of the electromagnetic radiation emitted by positive-energy electrons performing bound motion in the Coulomb field of a nucleus at rest in a strong uniform magnetic field. Bounded trajectories exist and span a wide range of velocity directions near the nucleus (compared to free trajectories with similar energies) when the electron Larmor radius is smaller than the distance at which the electron-nucleus Coulomb interaction energy is equal to the mechanical energy of an electron. The required conditions occur in magnetic white dwarf photospheres and have been achieved in experiments on production of antihydrogen. Under these conditions, the radiant power per unit volume emitted by positive-energy bound electrons is much higher than the analogous characteristic of bremsstrahlung (in particular, in thermal equilibrium) at frequencies that are below the electron cyclotron frequency but higher than the inverse transit time through the interaction region in a close collision in the absence of a magnetic field. The quantum energy discreteness of positive-energy bound states restricts the radiation from an ensemble of bound electrons (e.g., in thermal equilibrium) to nonoverlapping spectral lines, while continuum radiative transfer is dominated by linearly polarized bremsstrahlung.
Strong synergy of heat and modulated electromagnetic field in tumor cell killing.
Andocs, Gabor; Renner, Helmut; Balogh, Lajos; Fonyad, Laszlo; Jakab, Csaba; Szasz, Andras
2009-02-01
Hyperthermia is an emerging complementary method in radiooncology. Despite many positive studies and comprehensive reviews, the method is not widely accepted as a combination to radiotherapy. Modulated electrohyperthermia (mEHT; capacitive, electric field modulated, 13.56 MHz) has been used in clinical practice for almost 2 decades in Germany, Austria and Hungary. This in vivo study in nude mice xenograft tumors compares mEHT with "classic" radiative hyperthermia (radHT). Nude mice were xenografted with HT29 human colorectal carcinoma cells. 28 mice in four groups with seven animals each and two tumors per animal (totally 56 tumors) were included in the present study: group 1 as untreated control; group 2 treated with radHT at 42 degrees C; group 3 treated with mEHT at identical 42 degrees C; group 4 treated with mEHT at 38 degrees C (by intensively cooling down the tumor). 24 h after treatment, animals were sacrificed and the tumor cross sections studied by precise morphological methods for the respective relative amount of "dead" tumor cells. The effect of mEHT established a double effect as a synergy between the purely thermal (temperature-dependent) and nonthermal (not directly temperature-dependent) effects. The solely thermal enhancement ratio (TER) of cell killing was shown to be 2.9. The field enhancement ratio (FER) at a constant temperature of 42 degrees C was measured as 3.2. Their complex application significantly increased the therapeutic enhancement to 9.4. mEHT had a remarkable cancer cell-killing effect in a nude mice xenograft model.
Strong synergy of heat and modulated electromagnetic field in tumor cell killing
International Nuclear Information System (INIS)
Andocs, Gabor; Fonyad, Laszlo; Jakab, Csaba; Szasz, Andras
2009-01-01
Hyperthermia is an emerging complementary method in radiooncology. Despite many positive studies and comprehensive reviews, the method is not widely accepted as a combination to radiotherapy. Modulated electrohyperthermia (mEHT; capacitive, electric field modulated, 13.56 MHz) has been used in clinical practice for almost 2 decades in Germany, Austria and Hungary. This in vivo study in nude mice xenograft tumors compares mEHT with ''classic'' radiative hyperthermia (radHT). Nude mice were xenografted with HT29 human colorectal carcinoma cells. 28 mice in four groups with seven animals each and two tumors per animal (totally 56 tumors) were included in the present study: group 1 as untreated control; group 2 treated with radHT at 42 C; group 3 treated with mEHT at identical 42 C; group 4 treated with mEHT at 38 C (by intensively cooling down the tumor). 24 h after treatment, animals were sacrificed and the tumor cross sections studied by precise morphological methods for the respective relative amount of ''dead'' tumor cells. The effect of mEHT established a double effect as a synergy between the purely thermal (temperature-dependent) and nonthermal (not directly temperature-dependent) effects. The solely thermal enhancement ratio (TER) of cell killing was shown to be 2.9. The field enhancement ratio (FER) at a constant temperature of 42 C was measured as 3.2. Their complex application significantly increased the therapeutic enhancement to 9.4. mEHT had a remarkable cancer cell-killing effect in a nude mice xenograft model. (orig.)
Strong synergy of heat and modulated electromagnetic field in tumor cell killing
Energy Technology Data Exchange (ETDEWEB)
Andocs, Gabor [Frederic Joliot Curie National Research Inst. for Radiobiology and Radiohygiene, Budapest (Hungary)]|[St. Istvan Univ., Budapest (Hungary). Dept. of Pharmacology and Toxicology; Renner, Helmut [Klinikum Nuernberg (Germany). Clinic of Radiooncology; Balogh, Lajos [Frederic Joliot Curie National Research Inst. for Radiobiology and Radiohygiene, Budapest (Hungary); Fonyad, Laszlo [Semmelweis Univ., Budapest (Hungary). 1. Dept. of of Pathology and Experimental Cancer Research; Jakab, Csaba [St. Istvan Univ., Budapest (Hungary). Dept. of Pathology; Szasz, Andras [St. Istvan Univ., Goedoelloe (Hungary). Biotechnics Dept.
2009-02-15
Hyperthermia is an emerging complementary method in radiooncology. Despite many positive studies and comprehensive reviews, the method is not widely accepted as a combination to radiotherapy. Modulated electrohyperthermia (mEHT; capacitive, electric field modulated, 13.56 MHz) has been used in clinical practice for almost 2 decades in Germany, Austria and Hungary. This in vivo study in nude mice xenograft tumors compares mEHT with 'classic' radiative hyperthermia (radHT). Nude mice were xenografted with HT29 human colorectal carcinoma cells. 28 mice in four groups with seven animals each and two tumors per animal (totally 56 tumors) were included in the present study: group 1 as untreated control; group 2 treated with radHT at 42 C; group 3 treated with mEHT at identical 42 C; group 4 treated with mEHT at 38 C (by intensively cooling down the tumor). 24 h after treatment, animals were sacrificed and the tumor cross sections studied by precise morphological methods for the respective relative amount of 'dead' tumor cells. The effect of mEHT established a double effect as a synergy between the purely thermal (temperature-dependent) and nonthermal (not directly temperature-dependent) effects. The solely thermal enhancement ratio (TER) of cell killing was shown to be 2.9. The field enhancement ratio (FER) at a constant temperature of 42 C was measured as 3.2. Their complex application significantly increased the therapeutic enhancement to 9.4. mEHT had a remarkable cancer cell-killing effect in a nude mice xenograft model. (orig.)
Aspects of the flipped unification of strong, weak and electromagnetic interactions
Energy Technology Data Exchange (ETDEWEB)
Ellis, J.; Hagelin, J.S.; Kelley, S.; Nanopoulos, D.V.
1988-12-19
We explore phenomenological aspects of a recently proposed flipped SU(5) x U(1) supersymmetric GUT which incorporates an economical and natural mechanism for splitting Higgs doublets and triplets, and can be derived from string theory. Using experimental values of sin/sup 2/theta/sub W/ and the strong QCD coupling, we estimate the grand unification scale M/sub G/, where the strong and weak coupling strengths are equal, and the superunification scale M/sub SU/, where all couplings are equal. We find typical values of M/sub G/ approx. = 10/sup 15/ to 10/sup 17/ GeV, with M/sub SU/ somewhat higher and close to the value suggested by string models. We discuss different mechanisms for baryon decay, finding that the dominant one is gauge-boson exchange giving rise to p -> e/sup +/ /sup 0/, anti /sup +/ and n -> e/sup +/ /sup -/, anti /sup 0/ with partial lifetimes approx. = 10/sup 35+-2/ y. We show that a large GUT symmetry-breaking scale M/sub G/ is naturally generated by radiative corrections to the effective potential if a small amount approx. = m/sub W/ of soft supersymmetry breaking is generated dynamically at a large scale. We analyze the low-energy effective theory obtained using the renormalization group equations, demonstrating that electroweak symmetry breaking is obtained if m/sub t/ approx. = 60 to 90 GeV. We analyze the spectrum of sparticles, with particular attention to neutralinos.
Electron-photon and electron-electron interactions in the presence of strong electromagnetic fields
International Nuclear Information System (INIS)
Surzhykov, A.; Fritzsche, S.; Stoehlker, Th.
2010-01-01
During the last decade, photon emission from highly-charged, heavy ions has been in the focus of intense studies at the GSI accelerator and storage ring facility in Darmstadt. These studies have revealed unique information about the electron-electron and electron-photon interactions in the presence of extremely strong nuclear fields. Apart from the radiative electron capture processes, characteristic photon emission following collisional excitation of projectile ions has also attracted much interest. In this contribution, we summarize the recent theoretical studies on the production of excited ionic states and their subsequent radiative decay. We will pay special attention to the angular and polarization properties of Kα emission from helium-like ions produced by means of dielectronic recombination. The results obtained for this (resonant) capture process will be compared with the theoretical predictions for the characteristic X-rays following Coulomb excitation and radiative recombination of few-electron, heavy ions. Work is supported by Helmholtz Association and GSl under the project VH-NG--421. (author)
Resonant excitation and the decay of autoionization states in a strong electromagnetic field
International Nuclear Information System (INIS)
Andryushin, A.I.; Kazakov, A.E.; Fedorov, M.V.
1985-01-01
Photoionization of atoms involving resonant excitation of the auto-ionization state is studied. The evolution of the total ionization probability, its dependence on the frequency of the resonance radiation and also the photoelectron energy spectrum are investigated. It is shown that the energy of the final state of the system may be localized either in the vicinity of E approximately Esub(α), where Esub(α) is the auto-ionization energy, or in the vicinity of E approximately Esub(α)+h/2πω where h/2πω is the quantum energy of the resonance radiation. The photoelectron specturum in the region E approximately Esub(α)+h/2πω as a whole is similar to the electron spectrum on photoionization of atoms involving resonance excitation of the bound state. A strong effect on the photoelectron spectrum in the region E approximately Esub(α) is exerted by interference of various decay channels of the ground state in the resonance field which leads to the appearance in the spectrum of a characteristic structure of the Fano type. Interence also affects the widths of the two spectral curves, the relatve amount of electrons in the two energy ranges and also other characteristics of the ionization process. It is shown that the presence of a noninterfering photoionization channel of the autoionization state ensures the finiteness of the swidths and heights of the spectral curves and the absence of complete ''coherency merging''
Hot electromagnetic outflows. III. Displaced fireball in a strong magnetic field
International Nuclear Information System (INIS)
Thompson, Christopher; Gill, Ramandeep
2014-01-01
The evolution of a dilute electron-positron fireball is calculated in the regime of strong magnetization and high compactness (ℓ ∼ 10 3 -10 8 ). Heating is applied at a low effective temperature (<25 keV), appropriate to breakout from a confining medium, so that relaxation to a blackbody is inhibited by pair annihilation. The diffusion equation for Compton scattering by thermal pairs is coupled to a trans-relativistic cyclo-synchrotron source. We find that the photon spectrum develops a quasi-thermal peak at energy ∼0.1 m e c 2 in the comoving frame, with a power-law slope below it that is characteristic of gamma-ray bursts (GRBs; F ω ∼ const). The formation of a thermal high-energy spectrum is checked using the full kinetic equations. Calculations for a baryon-dominated photosphere reveal a lower spectral peak energy, and a harder low-energy spectrum, unless ion rest mass carries ≲ 10 –5 of the energy flux. We infer that (1) the GRB spectrum is inconsistent with the neutron-rich wind emitted by a young magnetar or neutron torus, and points to an event horizon in the engine; (2) neutrons play a negligible role in prompt gamma-ray emission; (3) the relation between observed peak frequency and burst energy is bounded below by the observed Amati relation if the Lorentz factor ∼(opening angle) –1 at breakout, and the jet is surrounded by a broader sheath that interacts with a collapsing stellar core; (4) X-ray flashes are consistent with magnetized jets with ion-dominated photospheres; (5) high-frequency Alfvén waves may become charge starved in the dilute pair gas; (6) limitations on magnetic reconnection from plasma collisionality have been overestimated.
Hot electromagnetic outflows. III. Displaced fireball in a strong magnetic field
Energy Technology Data Exchange (ETDEWEB)
Thompson, Christopher; Gill, Ramandeep [Canadian Institute for Theoretical Astrophysics, 60 St. George Street, Toronto, ON M5S 3H8 (Canada)
2014-08-10
The evolution of a dilute electron-positron fireball is calculated in the regime of strong magnetization and high compactness (ℓ ∼ 10{sup 3}-10{sup 8}). Heating is applied at a low effective temperature (<25 keV), appropriate to breakout from a confining medium, so that relaxation to a blackbody is inhibited by pair annihilation. The diffusion equation for Compton scattering by thermal pairs is coupled to a trans-relativistic cyclo-synchrotron source. We find that the photon spectrum develops a quasi-thermal peak at energy ∼0.1 m{sub e}c {sup 2} in the comoving frame, with a power-law slope below it that is characteristic of gamma-ray bursts (GRBs; F{sub ω} ∼ const). The formation of a thermal high-energy spectrum is checked using the full kinetic equations. Calculations for a baryon-dominated photosphere reveal a lower spectral peak energy, and a harder low-energy spectrum, unless ion rest mass carries ≲ 10{sup –5} of the energy flux. We infer that (1) the GRB spectrum is inconsistent with the neutron-rich wind emitted by a young magnetar or neutron torus, and points to an event horizon in the engine; (2) neutrons play a negligible role in prompt gamma-ray emission; (3) the relation between observed peak frequency and burst energy is bounded below by the observed Amati relation if the Lorentz factor ∼(opening angle){sup –1} at breakout, and the jet is surrounded by a broader sheath that interacts with a collapsing stellar core; (4) X-ray flashes are consistent with magnetized jets with ion-dominated photospheres; (5) high-frequency Alfvén waves may become charge starved in the dilute pair gas; (6) limitations on magnetic reconnection from plasma collisionality have been overestimated.
International Nuclear Information System (INIS)
Botelho, Luiz C.L.
2004-01-01
We analyze the triviality-quantum decoherence of Euclidean quantum chromodynamics in the gauge invariant quark current sector in the presence of a very strong external white-noise electromagnetic (strength) field within the context of QCD in the 't Hooft limit of a large number of colors
International Nuclear Information System (INIS)
Oeien, A.H.
1977-06-01
Sets of lower order and higher order kinetic and macroscopic equations are developed for a plasma where collisions are important but electrons and ions are allowed to have different temperatures when transports, due to gradients and fields, set in. Solving the lower order kinetic equations and taking appropriate velocity moments we show that usual classical transports emerge. From the higher order kinetic equations special notice is taken of some new correction terms to the classical transports. These corrections are linear in gradients and fields, some of which are found in a two-temperature state only. (Auth.)
Motion of charged particles in a knotted electromagnetic field
International Nuclear Information System (INIS)
Arrayas, M; Trueba, J L
2010-01-01
In this paper we consider the classical relativistic motion of charged particles in a knotted electromagnetic field. After reviewing how to construct electromagnetic knots from maps between the three-sphere and the two-sphere, we introduce a mean quadratic radius of the energy density distribution in order to study some properties of this field. We study the classical relativistic motion of electrons in the electromagnetic field of the Hopf map, and compute their trajectories. It is observed that these electrons initially at rest are strongly accelerated by the electromagnetic force, becoming ultrarelativistic in a period of time that depends on the knot energy and size.
Motion of charged particles in a knotted electromagnetic field
Energy Technology Data Exchange (ETDEWEB)
Arrayas, M; Trueba, J L, E-mail: joseluis.trueba@urjc.e [Area de Electromagnetismo, Universidad Rey Juan Carlos, Camino del Molino s/n, 28943 Fuenlabrada, Madrid (Spain)
2010-06-11
In this paper we consider the classical relativistic motion of charged particles in a knotted electromagnetic field. After reviewing how to construct electromagnetic knots from maps between the three-sphere and the two-sphere, we introduce a mean quadratic radius of the energy density distribution in order to study some properties of this field. We study the classical relativistic motion of electrons in the electromagnetic field of the Hopf map, and compute their trajectories. It is observed that these electrons initially at rest are strongly accelerated by the electromagnetic force, becoming ultrarelativistic in a period of time that depends on the knot energy and size.
Directory of Open Access Journals (Sweden)
Aldo Aoyagui Gomes Pereira
2017-12-01
Full Text Available Currently, the concept of vector potential is usually treated in textbooks and taught in university courses of electromagnetism as a mathematical device for the calculation of electric and magnetic fields. However, the historical investigation of the origin and development of this concept, especially in the works of Michael Faraday and James Clerk Maxwell, gave us indications that these scientists attributed physical and mechanical analogical meanings to the quantities that currently receive the denomination of vector potential. In the contexto in which these scientists worked in the second half of the nineteenth century, the scientific community considered that electromagnetic phenomena occurred in an ether with mechanical properties and that electromagnetic quantities should have mechanical analogues. At the end of this century, some physicists, including Oliver Heaviside and Heinrich Hertz reformulated Maxwell's theory, abandoning the physical interpretation given by Maxwell to the vector potential. In this paper, we discuss in a syntactic way how this process of change occurred. For this, we conducted a historical study based on primary and secondary sources on the subject and, finally, investigated the approach used in some textbooks of electromagnetism in teaching this concept. We also present indications that the abandonment of physical interpretation of the concept of vector potential has been associated with philosophical and methodological positions as well as with the interest in solving practical problems in the recent telegraph cable industry in nineteenth-century Britain.
International Nuclear Information System (INIS)
Recami, E.
1984-01-01
A review of tachyons, with particular attention to their classical theory, is presented. The extension of Special Relativity to tachyons in two dimensional is first presented, an elegant model-theory which allows a better understanding also of ordinary physics. Then, the results are extended to the four-dimensional case (particular on tachyon mechanics) that can be derived without assuming the existence of Super-luminal reference-frames. Localizability and the unexpected apparent shape of tachyonic objects are discussed, and it is shown (on the basis of tachyon kinematics) how to solve the common causal paradoxes. In connection with General Relativity, particularly the problem of the apparent superluminal expansions in astrophysics is reviewed. The problem (still open) of the extension of relativitic theories to tachyons in four dimensions is tackled, and the electromagnetic theory of tachyons, a topic that can be relevant also for the experimental side, is reviewed. (Author) [pt
Electromagnetic Education in India
Bajpai, Shrish; Asif, Siddiqui Sajida; Akhtar, Syed Adnan
2016-01-01
Out of the four fundamental interactions in nature, electromagnetics is one of them along with gravitation, strong interaction and weak interaction. The field of electromagnetics has made much of the modern age possible. Electromagnets are common in day-to-day appliances and are becoming more conventional as the need for technology increases.…
Franklin, Joel
2017-01-01
Classical field theory, which concerns the generation and interaction of fields, is a logical precursor to quantum field theory, and can be used to describe phenomena such as gravity and electromagnetism. Written for advanced undergraduates, and appropriate for graduate level classes, this book provides a comprehensive introduction to field theories, with a focus on their relativistic structural elements. Such structural notions enable a deeper understanding of Maxwell's equations, which lie at the heart of electromagnetism, and can also be applied to modern variants such as Chern–Simons and Born–Infeld. The structure of field theories and their physical predictions are illustrated with compelling examples, making this book perfect as a text in a dedicated field theory course, for self-study, or as a reference for those interested in classical field theory, advanced electromagnetism, or general relativity. Demonstrating a modern approach to model building, this text is also ideal for students of theoretic...
International Nuclear Information System (INIS)
Burch, Aidan
2004-01-01
Working within the HPO (History Projection Operator) Consistent Histories formalism, we follow the work of Savvidou on (scalar) field theory [J. Math. Phys. 43, 3053 (2002)] and that of Savvidou and Anastopoulos on (first-class) constrained systems [Class. Quantum Gravt. 17, 2463 (2000)] to write a histories theory (both classical and quantum) of Electromagnetism. We focus particularly on the foliation-dependence of the histories phase space/Hilbert space and the action thereon of the two Poincare groups that arise in histories field theory. We quantize in the spirit of the Dirac scheme for constrained systems
Botyánszki, János; Kasen, Daniel; Plewa, Tomasz
2018-01-01
The classic single-degenerate model for the progenitors of Type Ia supernova (SN Ia) predicts that the supernova ejecta should be enriched with solar-like abundance material stripped from the companion star. Spectroscopic observations of normal SNe Ia at late times, however, have not resulted in definite detection of hydrogen. In this Letter, we study line formation in SNe Ia at nebular times using non-LTE spectral modeling. We present, for the first time, multidimensional radiative transfer calculations of SNe Ia with stripped material mixed in the ejecta core, based on hydrodynamical simulations of ejecta–companion interaction. We find that interaction models with main-sequence companions produce significant Hα emission at late times, ruling out these types of binaries being viable progenitors of SNe Ia. We also predict significant He I line emission at optical and near-infrared wavelengths for both hydrogen-rich or helium-rich material, providing an additional observational probe of stripped ejecta. We produce models with reduced stripped masses and find a more stringent mass limit of M st ≲ 1 × 10‑4 M ⊙ of stripped companion material for SN 2011fe.
Beyond quantum-classical analogies: high time for agreement?
Marrocco, Michele
Lately, many quantum-classical analogies have been investigated and published in many acknowledged journals. Such a surge of research on conceptual connections between quantum and classical physics forces us to ask whether the correspondence between the quantum and classical interpretation of the reality is deeper than the correspondence principle stated by Bohr. Here, after a short introduction to quantum-classical analogies from the recent literature, we try to examine the question from the perspective of a possible agreement between quantum and classical laws. A paradigmatic example is given in the striking equivalence between the classical Mie theory of electromagnetic scattering from spherical scatterers and the corresponding quantum-mechanical wave scattering analyzed in terms of partial waves. The key features that make the correspondence possible are examined and finally employed to deal with the fundamental blackbody problem that marks the initial separation between classical and quantum physics. The procedure allows us to recover the blackbody spectrum in classical terms and the proof is rich in consequences. Among them, the strong analogy between the quantum vacuum and its classical counterpart.
Strong, John
1958-01-01
An intermediate course in optics, this volume explores both experimental and theoretical concepts, offering practical knowledge of geometrical optics that will enhance students' comprehension of any relevant applied science. Its exposition of the concepts of classical optics is presented with a minimum of mathematical detail but presumes some knowledge of calculus, vectors, and complex numbers.Subjects include light as wave motion; superposition of wave motions; electromagnetic waves; interaction of light and matter; velocities and scattering of light; polarized light and dielectric boundarie
International Nuclear Information System (INIS)
Costella, J.P.; McKellar, B.H.J.; Rawlinson, A.A.
1997-03-01
We review how antiparticles may be introduced in classical relativistic mechanics, and emphasize that many of their paradoxical properties can be more transparently understood in the classical than in the quantum domain. (authors)
International Nuclear Information System (INIS)
Kim, Se Yun
2009-01-01
This book deals with engineering electromagnetics. It contains seven chapters, which treats understanding of engineering electromagnetics such as magnet and electron spin, current and a magnetic field and an electromagnetic wave, Essential tool for engineering electromagnetics on rector and scalar, rectangular coordinate system and curl vector, electrostatic field with coulomb rule and method of electric images, Biot-Savart law, Ampere law and magnetic force, Maxwell equation and an electromagnetic wave and reflection and penetration of electromagnetic plane wave.
Kochetov, A. V.
2018-05-01
This work was initiated by experiments on studying the self-action of radio waves incident on the ionosphere from a ground-based transmitter at the stage of electromagnetic excitation of Langmuir turbulence (Langmuir effect). The emphasis is on the impact of "self-consistent" collisionless absorption of radio waves by the Langmuir turbulence, which develops when the incident-wave field swells in the resonant region of a smoothly inhomogeneous plasma, on the dynamics of the radio wave reflection. Electrodynamic characteristics of the nonlinear-plasma layer, which has a linear unperturbed profile of the plasma density, with different features of the absorption development are obtained for a high intensity of the incident radiation. Calculations of "soft" and "hard" regimes of the absorption occurrence, as well as hysteresis modes in which the damping switch-on and off thresholds differ several times, are carried out. The algorithms we devised and the results of the study can serve as the basis for a more adequate and more detailed numerical simulation for interpretation of the experimental data obtained at the stage of the Langmuir effect in the ionosphere.
Itoh, Tamitake; Yamamoto, Yuko S.
2017-11-01
Electronic transition rates of a molecule located at a crevasse or a gap of a plasmonic nanoparticle (NP) dimer are largely enhanced up to the factor of around 106 due to electromagnetic (EM) coupling between plasmonic and molecular electronic resonances. The coupling rate is determined by mode density of the EM fields at the crevasse and the oscillator strength of the local electronic resonance of a molecule. The enhancement by EM coupling at a gap of plasmonic NP dimer enables us single molecule (SM) Raman spectroscopy. Recently, this type of research has entered a new regime wherein EM enhancement effects cannot be treated by conventional theorems, namely EM mechanism. Thus, such theorems used for the EM enhancement effect should be re-examined. We here firstly summarize EM mechanism by using surface-enhanced Raman scattering (SERS), which is common in EM enhancement phenomena. Secondly, we focus on recent two our studies on probing SM fluctuation by SERS within the spatial resolution of sub-nanometer scales. Finally, we discuss the necessity of re-examining the EM mechanism with respect to two-fold breakdowns of the weak coupling assumption: the breakdown of Kasha's rule induced by the ultra-fast plasmonic de-excitation and the breakdown of the weak coupling by EM coupling rates exceeding both the plasmonic and molecular excitonic dephasing rates.
Computational electromagnetic-aerodynamics
Shang, Joseph J S
2016-01-01
Presents numerical algorithms, procedures, and techniques required to solve engineering problems relating to the interactions between electromagnetic fields, fluid flow, and interdisciplinary technology for aerodynamics, electromagnetics, chemical-physics kinetics, and plasmadynamics This book addresses modeling and simulation science and technology for studying ionized gas phenomena in engineering applications. Computational Electromagnetic-Aerodynamics is organized into ten chapters. Chapter one to three introduce the fundamental concepts of plasmadynamics, chemical-physics of ionization, classical magnetohydrodynamics, and their extensions to plasma-based flow control actuators, high-speed flows of interplanetary re-entry, and ion thrusters in space exploration. Chapter four to six explain numerical algorithms and procedures for solving Maxwell’s equation in the time domain for computational electromagnetics, plasma wave propagation, and the time-dependent c mpressible Navier-Stokes equation for aerodyn...
DEFF Research Database (Denmark)
This book is dedicated to various aspects of electromagnetic wave theory and its applications in science and technology. The covered topics include the fundamental physics of electromagnetic waves, theory of electromagnetic wave propagation and scattering, methods of computational analysis......, material characterization, electromagnetic properties of plasma, analysis and applications of periodic structures and waveguide components, etc....
Classical and Quantum Chaos in Atom Optics
Saif, Farhan
2006-01-01
The interaction of an atom with an electromagnetic field is discussed in the presence of a time periodic external modulating force. It is explained that a control on atom by electromagnetic fields helps to design the quantum analog of classical optical systems. In these atom optical systems chaos may appear at the onset of external fields. The classical and quantum chaotic dynamics is discussed, in particular in an atom optics Fermi accelerator. It is found that the quantum dynamics exhibits ...
International Nuclear Information System (INIS)
Lusanna, Luca
2004-01-01
The four (electro-magnetic, weak, strong and gravitational) interactions are described by singular Lagrangians and by Dirac-Bergmann theory of Hamiltonian constraints. As a consequence a subset of the original configuration variables are gauge variables, not determined by the equations of motion. Only at the Hamiltonian level it is possible to separate the gauge variables from the deterministic physical degrees of freedom, the Dirac observables, and to formulate a well posed Cauchy problem for them both in special and general relativity. Then the requirement of causality dictates the choice of retarded solutions at the classical level. However both the problems of the classical theory of the electron, leading to the choice of (1/2) (retarded + advanced) solutions, and the regularization of quantum field theory, leading to the Feynman propagator, introduce anticipatory aspects. The determination of the relativistic Darwin potential as a semi-classical approximation to the Lienard-Wiechert solution for particles with Grassmann-valued electric charges, regularizing the Coulomb self-energies, shows that these anticipatory effects live beyond the semi-classical approximation (tree level) under the form of radiative corrections, at least for the electro-magnetic interaction.Talk and 'best contribution' at The Sixth International Conference on Computing Anticipatory Systems CASYS'03, Liege August 11-16, 2003
Curved electromagnetic missiles
International Nuclear Information System (INIS)
Myers, J.M.; Shen, H.M.; Wu, T.T.
1989-01-01
Transient electromagnetic fields can exhibit interesting behavior in the limit of great distances from their sources. In situations of finite total radiated energy, the energy reaching a distant receiver can decrease with distance much more slowly than the usual r - 2 . Cases of such slow decrease have been referred to as electromagnetic missiles. All of the wide variety of known missiles propagate in essentially straight lines. A sketch is presented here of a missile that can follow a path that is strongly curved. An example of a curved electromagnetic missile is explicitly constructed and some of its properties are discussed. References to details available elsewhere are given
Benacquista, Matthew J
2018-01-01
This textbook provides an introduction to classical mechanics at a level intermediate between the typical undergraduate and advanced graduate level. This text describes the background and tools for use in the fields of modern physics, such as quantum mechanics, astrophysics, particle physics, and relativity. Students who have had basic undergraduate classical mechanics or who have a good understanding of the mathematical methods of physics will benefit from this book.
Construction of classical and non-classical coherent photon states
International Nuclear Information System (INIS)
Honegger, Reinhard; Rieckers, Alfred
2001-01-01
It is well known that the diagonal matrix elements of all-order coherent states for the quantized electromagnetic field have to constitute a Poisson distribution with respect to the photon number. The present work gives first the summary of a constructive scheme, developed previously, which determines in terms of an auxiliary Hilbert space all possible off-diagonal elements for the all-order coherent density operators in Fock space and which identifies all extremal coherent states. In terms of this formalism it is then demonstrated that each pure classical coherent state is a uniformly phase locked (quantum) coherent superposition of number states. In a mixed classical coherent state the exponential of the locked phase is shown to be replaced by a rather arbitrary unitary operator in the auxiliary Hilbert space. On the other hand classes for density operators--and for their normally ordered characteristic functions--of non-classical coherent states are obtained, especially by rather weak perturbations of classical coherent states. These illustrate various forms of breaking the classical uniform phase locking and exhibit rather peculiar properties, such as asymmetric fluctuations for the quadrature phase operators. Several criteria for non-classicality are put forward and applied to the elaborated non-classical coherent states, providing counterexamples against too simple arguments for classicality. It is concluded that classicality is only a stable concept for coherent states with macroscopic intensity
EASTHAM, PAUL
2003-01-01
PUBLISHED We connect three phenomena in which a coherent electromagnetic field could be generated: polariton condensation, phase-locking in arrays of underdamped Josephson junctions, and lasing. All these phenomena have been described using Dicke-type models of spins coupled to a single photon mode. These descriptions may be distinguished by whether the spins are quantum or classical, and whether they are strongly or weakly damped.
Applied electromagnetic scattering theory
Osipov, Andrey A
2017-01-01
Besides classical applications (radar and stealth, antennas, microwave engineering), scattering and diffraction are enabling phenomena for some emerging research fields (artificial electromagnetic materials or metamaterials, terahertz technologies, electromagnetic aspects of nano-science). This book is a tutorial for advanced students who need to study diffraction theory. The textbook gives fundamental knowledge about scattering and diffraction of electromagnetic waves and provides some working examples of solutions for practical high-frequency scattering and diffraction problems. The book focuses on the most important diffraction effects and mechanisms influencing the scattering process and describes efficient and physically justified simulation methods - physical optics (PO) and the physical theory of diffraction (PTD) - applicable in typical remote sensing scenarios. The material is presented in a comprehensible and logical form, which relates the presented results to the basic principles of electromag...
Electromagnetic polarizabilities of hadrons
International Nuclear Information System (INIS)
Friar, J.L.
1988-01-01
Electromagnetic polarizabilities of hadrons are reviewed, after a discussion of classical analogues. Differences between relativistic and non-relativistic approaches can lead to conflicts with conventional nuclear physics sum rules and calculational techniques. The nucleon polarizabilities are discussed in the context of the non-relativistic valence quark model, which provides a good qualitative description. The recently measured pion polarizabilities are discussed in the context of chiral symmetry and quark-loop models. 58 refs., 5 figs
Electromagnetic processes in strong crystalline fields
Uggerhoj, U I; Esberg, J; Knudsen, H; Lund, M; Møller, S P; Sørensen, A H; Thomsen, A H; Uggerhøj, U I; Geissel, H; Scheidenberger, C; Weick, H; Winfield, J; Sona, P; Connell S; Ballestrero, S; Ketel, T; Dizdar, A; Mangiarotti, A
2009-01-01
As an addendum to the NA63 proposal cite{Ande05}, we propose to measure 1) the Landau-Pomeranchuk-Migdal (LPM) effect in low-$Z$ targets, 2) Magnetic suppression of incoherent bremsstrahlung resulting from exposure to an external field during the emission event, and 3) the bremsstrahlung emission from relativistic ($gamma=170$), fully stripped Pb nuclei penetrating various amorphous targets. Concerning the LPM effect, both the 'traditional' Migdal approach and the modern treatment by Baier and Katkov display inaccuracies, i.e. a possible lack of applicability in low-$Z$ targets. Moreover, the LPM effect has been shown to have a significant impact on giant air showers for energies in the EeV range - evidently processes in a low-$Z$ material. A measurement of magnetic suppression is demanding in terms of necessary accuracy (an expected $lesssim$15% effect), but would prove the existence of a basic interplay between coherent and incoherent processes, also believed to be significant in beamstrahlung emission. For...
Electromagnetic probes of strongly interacting matter
Indian Academy of Sciences (India)
2015-05-07
May 7, 2015 ... The nuclear matter under extreme conditions of temperatures () and baryonic densities () undergoes a phase transition to quark gluon plasma (QGP). It is expected that such extreme conditions can be achieved by colliding nuclei at ultrarelativistic energies. In the present review, the suitability of ...
Supersymmetry and weak, electromagnetic and strong interactions
International Nuclear Information System (INIS)
Fayet, P.
1977-01-01
A supersymmetric theory of particle interactions is discussed. It is based on the earlier model which involves gauge (or vector) superfields, and matter (or chiral) superfields; each of them describes a vector and a Majorana spinor in the first case, or a two-component Dirac spinor and a complex scalar in the second case. The new theory suggests the possible existence of spin - 1/2 gluons and heavy spin-0 quarks, besides spin - 1 gluons and spin - 1/2 quarks. To prevent scalar particles to be exchanged in processes such as μ or β decays a new class of leptons with its own quantum number is introduced; it includes charged leptons and a ''photonic neutrino''
Electromagnetic probes of strongly interacting matter
Indian Academy of Sciences (India)
2015-05-07
May 7, 2015 ... Collisions between two nuclei at relativistic energies will create charged particles – either in .... The thermal cutting rules give a systematic procedure to express ...... mesons due to its interaction with the thermal partons [80] and employment of running .... [16] J Deng, Q Wang, N Xu and P Zhuang, Phys. Lett.
Electromagnetic actuation in MEMS switches
DEFF Research Database (Denmark)
Oliveira Hansen, Roana Melina de; Mátéfi-Tempfli, Mária; Chemnitz, Steffen
. Electromagnetic actuation is a very promising approach to operate such MEMS and Power MEMS devices, due to the long range, reproducible and strong forces generated by this method, among other advantages. However, the use of electromagnetic actuation in such devices requires the use of thick magnetic films, which...
Classical models for Regge trajectories
International Nuclear Information System (INIS)
Biedenharn, L.C.; Van Dam, H.; Marmo, G.; Morandi, G.; Mukunda, N.; Samuel, J.; Sudarshan, E.C.G.
1987-01-01
Two classical models for particles with internal structure and which describe Regge trajectories are developed. The remarkable geometric and other properties of the two internal spaces are highlighted. It is shown that the conditions of positive time-like four-velocity and energy momentum for the classical system imply strong and physically reasonable conditions on the Regge mass-spin relationship
Relativistic nonlinear electrodynamics the QED vacuum and matter in super-strong radiation fields
Avetissian, Hamlet K
2016-01-01
This revised edition of the author’s classic 2006 text offers a comprehensively updated review of the field of relativistic nonlinear electrodynamics. It explores the interaction of strong and super-strong electromagnetic/laser radiation with the electromagnetic quantum vacuum and diverse types of matter – including free charged particles and antiparticles, acceleration beams, plasma and plasmous media. The appearance of laser sources of relativistic and ultra-relativistic intensities over the last decade has stimulated investigation of a large class of processes under such super-strong radiation fields. Revisions for this second edition reflect these developments and the book includes new chapters on Bremsstrahlung and nonlinear absorption of superintense radiation in plasmas, the nonlinear interaction of relativistic atoms with intense laser radiation, nonlinear interaction of strong laser radiation with Graphene, and relativistic nonlinear phenomena in solid-plasma targets under supershort laser pul...
Energy Technology Data Exchange (ETDEWEB)
Yamashita, H; Marinova, I; Cingoski, V [eds.
2002-07-01
These proceedings contain papers relating to the 3rd Japanese-Bulgarian-Macedonian Joint Seminar on Applied Electromagnetics. Included are the following groups: Numerical Methods I; Electrical and Mechanical System Analysis and Simulations; Inverse Problems and Optimizations; Software Methodology; Numerical Methods II; Applied Electromagnetics.
International Nuclear Information System (INIS)
Yamashita, H.; Marinova, I.; Cingoski, V.
2002-01-01
These proceedings contain papers relating to the 3rd Japanese-Bulgarian-Macedonian Joint Seminar on Applied Electromagnetics. Included are the following groups: Numerical Methods I; Electrical and Mechanical System Analysis and Simulations; Inverse Problems and Optimizations; Software Methodology; Numerical Methods II; Applied Electromagnetics
The chronicle of the classical electrodynamics
International Nuclear Information System (INIS)
Bassalo, J.M.F.
1984-01-01
In this Chronicle of the classical electrodynamics it is shown how this important branch of classical physics was developed since the mathematical formulation of the electromagnetism empiric laws carried by Maxwell, mainly the laws of Coulomb, Oersted, Ampere, Biot-Savart, Faraday, Henry and Lenz, up to the settlement of the radiation theory, scientific background for the technological development of the wireless telegraphy. Through this chronicle, it is also seen how Maxwell got one of the main results of the past century classical physics - the electromagnetic theory of light -, and how the experimental production of an electromagnetic wave by Hertz, unchained a collection of theoretical papers which explained many experimental results such as dispersion of light, thermical radiation, X-rays and its scattering through the matter. At last, it is still seen that the study of electrodynamics of moving bodies led to the relativity theory, presented by Einstein's famous paper about such subject. (Author) [pt
CERN. Geneva; Franklin, M
2001-01-01
These will be a set of lectures on classic particle physics experiments, with emphasis on how the emasurements are made. I will discuss experiments made to measure the electric charge distribution of particles, to measure the symmetries of the weak decays, to measure the magnetic moment of the muon. As well as experiments performed which discovered new particles or resonances, like the tAU2and the J/Psi. The coverage will be general and should be understandable to someone knowing little particle physics.
Classical and quantum dynamics from classical paths to path integrals
Dittrich, Walter
2017-01-01
Graduate students who wish to become familiar with advanced computational strategies in classical and quantum dynamics will find in this book both the fundamentals of a standard course and a detailed treatment of the time-dependent oscillator, Chern-Simons mechanics, the Maslov anomaly and the Berry phase, to name just a few topics. Well-chosen and detailed examples illustrate perturbation theory, canonical transformations and the action principle, and demonstrate the usage of path integrals. The fifth edition has been revised and enlarged to include chapters on quantum electrodynamics, in particular, Schwinger’s proper time method and the treatment of classical and quantum mechanics with Lie brackets and pseudocanonical transformations. It is shown that operator quantum electrodynamics can be equivalently described with c-numbers, as demonstrated by calculating the propagation function for an electron in a prescribed classical electromagnetic field.
Classical and quantum chaos in atom optics
International Nuclear Information System (INIS)
Saif, Farhan
2005-01-01
The interaction of an atom with an electro-magnetic field is discussed in the presence of a time periodic external modulating force. It is explained that a control on atom by electro-magnetic fields helps to design the quantum analog of classical optical systems. In these atom optical systems chaos may appear at the onset of external fields. The classical and quantum chaotic dynamics is discussed, in particular in an atom optics Fermi accelerator. It is found that the quantum dynamics exhibits dynamical localization and quantum recurrences
Interactions of free electrons with an electromagnetic radiation
Energy Technology Data Exchange (ETDEWEB)
Zel' dovich, Ya B [AN SSSR, Moscow. Inst. Prikladnoj Matematiki
1975-02-01
The interaction of a chaotic field of electromagnetic radiation with free electrons in plasma is considered as applied to astrophysical problems, in particular, to the theory of establishing thermodynamic equilibrium of radiation in the hot universe. The kinetic equation describes a change in the spectrum; particular attention is paid to the induced scattering and to the classical interpretation of the induced transfer of energy and momentum. In spectra of radiosources with a high brightness temperature the induced scattering may lead to the Bose condensation of photons, shock wave and appearance of solutions. The scattering of strong low-frequency waves is considered as applied to pulsars and laboratory coherent generators.
International Nuclear Information System (INIS)
Miller, J.S.
1987-01-01
An electromagnetic shield is described comprising: closed, electrically-conductive rings, each having an open center; and binder means for arranging the rings in a predetermined, fixed relationship relative to each other, the so-arranged rings and binder means defining an outer surface; wherein electromagnetic energy received by the shield from a source adjacent its outer surface induces an electrical current to flow in a predetermined direction adjacent and parallel to the outer surface, through the rings; and wherein each ring is configured to cause source-induced alternating current flowing through the portion of the ring closest to the outer surface to electromagnetically induce an oppositely-directed current in the portion of the ring furthest from the surface, such oppositely-directed current bucking any source-induced current in the latter ring portion and thus reducing the magnitude of current flowing through it, whereby the electromagnetic shielding effected by the shield is enhanced
Thomas, David T; Hartnett, James P; Hughes, William F
1973-01-01
The applications involving electromagnetic fields are so pervasive that it is difficult to estimate their contribution to the industrial output: generation of electricity, power transmission lines, electric motors, actuators, relays, radio, TV and microwave transmission and reception, magnetic storage, and even the mundane little magnet used to hold a paper note on the refrigerator are all electromagnetic in nature. One would be hard pressed to find a device that works without relaying on any electromagnetic principle or effect. This text provides a good theoretical understanding of the electromagnetic field equations but also treats a large number of applications. In fact, no topic is presented unless it is directly applicable to engineering design or unless it is needed for the understanding of another topic. In electrostatics, for example, the text includes discussions of photocopying, ink-jet printing, electrostatic separation and deposition, sandpaper production, paint spraying, and powder coating. In ma...
Greenwood, Donald T
1997-01-01
Graduate-level text for science and technology students provides strong background in the more abstract and intellectually satisfying areas of dynamical theory. Topics include d'Alembert's principle and the idea of virtual work, Hamilton's equations, Hamilton-Jacobi theory, canonical transformations, more. Problems and references at chapter ends.
DEFF Research Database (Denmark)
Cermak, Daniel; Okutsu, Ayaka; Jørgensen, Stina Marie Hasse
2015-01-01
Daniel Cermak-Sassenrath, Ayaka Okutsu, Stina Hasse. Electromagnetic Landscape - In-between Signal, Noise and Environment. Installation and artist talk. 21th International Symposium on Electronic Art (ISEA) 2015, Vancouver, CAN, Aug 14-18, 2015.......Daniel Cermak-Sassenrath, Ayaka Okutsu, Stina Hasse. Electromagnetic Landscape - In-between Signal, Noise and Environment. Installation and artist talk. 21th International Symposium on Electronic Art (ISEA) 2015, Vancouver, CAN, Aug 14-18, 2015....
Introduction to electromagnetic engineering
Harrington, Roger E
2003-01-01
This study of electromagnetic theory introduces students to a broad range of quantities and concepts, imparting the necessary vector analysis and associated mathematics and reinforcing its teachings with several elementary field problems. Based on circuit theory rather than on the classical force-relationship approach, the text uses the theory of electric circuits to provide a system of experiments already familiar to the electrical engineer; a series of field concepts are then introduced as a logical extension of circuit theory. Virtually unobtainable elsewhere, this text was written by a pr
International Nuclear Information System (INIS)
Carson, L.J.
1980-01-01
Quantum chromodynamics (QCD) is currently our only candidate for a theory of strong-interaction dynamics. But the evidence for it is very scanty. Indeed, QCD has only been experimentally verified in its predictions of scaling violation in deep inelastic neutrino scattering. Yet, research continues on QCD because it is based on a beautiful idea, namely the incorporation of observed particle symmetries via local gauge invariance. Nevertheless QCD, a quantum field theory in 3 + 1 dimensions is still without solution. The sheer difficulty in solving the full quantum problem has led some to various approximations, in the hopes of shedding light on the structure of the theory. (orig./FKS)
Physical restrictions on the choice of electromagnetic gauge and their practical consequences
International Nuclear Information System (INIS)
Reiss, H R
2017-01-01
It is shown that electromagnetic potentials convey physical information beyond that supplied by electric and magnetic fields alone, and are thus more fundamental. Observable physical properties can impose conditions on the selection of electromagnetic gauge (i.e. sets of potentials) that are explicit and restrictive. This is true both classically and quantum mechanically. The implication that the choice of gauge carries physical information is confirmed by exhibiting a set of potentials that describes fields correctly, but that violates physical constraints. The basic conclusions are that physical requirements place limits on acceptable gauges; and that potentials are more fundamental than fields in both classical and quantum physics, representing a major generalization of the quantum-only Aharonov–Bohm effect. These important properties are obscured if the dipole approximation is employed. The properties demonstrated here relate directly to conditions that exist in strong-field laser applications. (paper)
Han, Song; Cong, Longqing; Lin, Hai; Xiao, Boxun; Yang, Helin; Singh, Ranjan
2016-01-01
Metamaterials have recently enabled coupling induced transparency due to interference effects in coupled subwavelength resonators. In this work, we present a three dimensional (3-D) metamaterial design with six-fold rotational symmetry that shows electromagnetically induced transparency with a strong polarization dependence to the incident electromagnetic wave due to the ultra-sharp resonance line width as a result of interaction between the constituent meta-atoms. However, when the six-fold rotationally symmetric unit cell design was re-arranged into a fourfold rotational symmetry, we observed the excitation of a polarization insensitive dual-band transparency. Thus, the 3-D split-ring resonators allow new schemes to observe single and multi-band classical analogues of electromagnetically induced transparencies that has huge potential applications in slowing down light, sensing modalities, and filtering functionalities either in the passive mode or the active mode where such effects could be tuned by integrating materials with dynamic properties. PMID:26857034
Diminuendo: Classical Music and the Academy
Asia, Daniel
2010-01-01
How is the tradition of Western classical music faring on university campuses? Before answering this question, it is necessary to understand what has transpired with classical music in the wider culture, as the relationship between the two is so strong. In this article, the author discusses how classical music has taken a big cultural hit in…
Quantum and classical dissipation of charged particles
Energy Technology Data Exchange (ETDEWEB)
Ibarra-Sierra, V.G. [Departamento de Física, Universidad Autónoma Metropolitana at Iztapalapa, Av. San Rafael Atlixco 186, Col. Vicentina, 09340 México D.F. (Mexico); Anzaldo-Meneses, A.; Cardoso, J.L.; Hernández-Saldaña, H. [Área de Física Teórica y Materia Condensada, Universidad Autónoma Metropolitana at Azcapotzalco, Av. San Pablo 180, Col. Reynosa-Tamaulipas, Azcapotzalco, 02200 México D.F. (Mexico); Kunold, A., E-mail: akb@correo.azc.uam.mx [Área de Física Teórica y Materia Condensada, Universidad Autónoma Metropolitana at Azcapotzalco, Av. San Pablo 180, Col. Reynosa-Tamaulipas, Azcapotzalco, 02200 México D.F. (Mexico); Roa-Neri, J.A.E. [Área de Física Teórica y Materia Condensada, Universidad Autónoma Metropolitana at Azcapotzalco, Av. San Pablo 180, Col. Reynosa-Tamaulipas, Azcapotzalco, 02200 México D.F. (Mexico)
2013-08-15
A Hamiltonian approach is presented to study the two dimensional motion of damped electric charges in time dependent electromagnetic fields. The classical and the corresponding quantum mechanical problems are solved for particular cases using canonical transformations applied to Hamiltonians for a particle with variable mass. Green’s function is constructed and, from it, the motion of a Gaussian wave packet is studied in detail. -- Highlights: •Hamiltonian of a damped charged particle in time dependent electromagnetic fields. •Exact Green’s function of a charged particle in time dependent electromagnetic fields. •Time evolution of a Gaussian wave packet of a damped charged particle. •Classical and quantum dynamics of a damped electric charge.
Quantum and classical dissipation of charged particles
International Nuclear Information System (INIS)
Ibarra-Sierra, V.G.; Anzaldo-Meneses, A.; Cardoso, J.L.; Hernández-Saldaña, H.; Kunold, A.; Roa-Neri, J.A.E.
2013-01-01
A Hamiltonian approach is presented to study the two dimensional motion of damped electric charges in time dependent electromagnetic fields. The classical and the corresponding quantum mechanical problems are solved for particular cases using canonical transformations applied to Hamiltonians for a particle with variable mass. Green’s function is constructed and, from it, the motion of a Gaussian wave packet is studied in detail. -- Highlights: •Hamiltonian of a damped charged particle in time dependent electromagnetic fields. •Exact Green’s function of a charged particle in time dependent electromagnetic fields. •Time evolution of a Gaussian wave packet of a damped charged particle. •Classical and quantum dynamics of a damped electric charge
Mathematical methods of electromagnetic theory
Friedrichs, Kurt O
2014-01-01
This text provides a mathematically precise but intuitive introduction to classical electromagnetic theory and wave propagation, with a brief introduction to special relativity. While written in a distinctive, modern style, Friedrichs manages to convey the physical intuition and 19th century basis of the equations, with an emphasis on conservation laws. Particularly striking features of the book include: (a) a mathematically rigorous derivation of the interaction of electromagnetic waves with matter, (b) a straightforward explanation of how to use variational principles to solve problems in el
International Nuclear Information System (INIS)
Ito, Koji; Suetake, Norio; Aizawa, Toshie; Nakasaki, Masayoshi
1998-01-01
The present invention provides an electromagnetic pump suitable to a recycling pump for liquid sodium as coolants of an FBR type reactor. Namely, a stator module of the electromagnetic pump of the present invention comprises a plurality of outer laminate iron core units and outer stator modules stacked alternately in the axial direction. With such a constitution, even a long electromagnetic pump having a large number of outer stator coils can be manufactured without damaging electric insulation of the outer stator coils. In addition, the inner circumferential surface of the outer laminate iron cores is urged and brought into contact with the outer circumferential surface of the outer duct by an elastic material. With such a constitution, Joule loss heat generated in the outer stator coils and internal heat generated in the outer laminate iron cores can be released to an electroconductive fluid flowing the inner circumference of the outer duct by way of the outer duct. (I.S.)
A classical model for the electron
International Nuclear Information System (INIS)
Visser, M.
1989-01-01
The construction of classical and semi-classical models for the electron has had a long and distinguished history. Such models are useful more for what they teach us about field theory than what they teach us about the electron. In this Letter I exhibit a classical model of the electron consisting of ordinary electromagnetism coupled with a self-interacting version of Newtonian gravity. The gravitational binding energy of the system balances the electrostatic energy in such a manner that the total rest mass of the electron is finite. (orig.)
In-Depth Development of Classical Electrodynamics
Directory of Open Access Journals (Sweden)
Keilman Y. N.
2008-01-01
Full Text Available There is hope that a properly developed Classical Electrodynamics (CED will be able to play a role in a unified field theory explaining electromagnetism, quantum phenomena, and gravitation. There is much work that has to be done in this direction. In this article we propose a move towards this aim by refining the basic principles of an improved CED. Attention is focused on the reinterpretation of the E-M potential. We use these basic principles to obtain solutions that explain the interactions between a constant electromagnetic field and a thin layer of material continuum; between a constant electromagnetic field and a spherical configuration of material continuum (for a charged elementary particle; between a transverse electromagnetic wave and a material continuum; between a longitudinal aether wave (dummy wave and a material continuum.
Mathematical methods of classical physics
Cortés, Vicente
2017-01-01
This short primer, geared towards students with a strong interest in mathematically rigorous approaches, introduces the essentials of classical physics, briefly points out its place in the history of physics and its relation to modern physics, and explains what benefits can be gained from a mathematical perspective. As a starting point, Newtonian mechanics is introduced and its limitations are discussed. This leads to and motivates the study of different formulations of classical mechanics, such as Lagrangian and Hamiltonian mechanics, which are the subjects of later chapters. In the second part, a chapter on classical field theories introduces more advanced material. Numerous exercises are collected in the appendix.
DEFF Research Database (Denmark)
Cermak, Daniel; Okutsu, Ayaka; Hasse, Stina
2015-01-01
Electromagnetic Landscape demonstrates in direct, tangible and immediate ways effects of the disruption of the familiar. An ubiquitous technological medium, FM radio, is turned into an alien and unfamiliar one. Audience participation, the environment, radio signals and noise create a site...
Improved Electromagnetic Brake
Martin, Toby B.
2004-01-01
A proposed design for an electromagnetic brake would increase the reliability while reducing the number of parts and the weight, relative to a prior commercially available electromagnetic brake. The reductions of weight and the number of parts could also lead to a reduction of cost. A description of the commercial brake is prerequisite to a description of the proposed electromagnetic brake. The commercial brake (see upper part of figure) includes (1) a permanent magnet and an electromagnet coil on a stator and (2) a rotor that includes a steel contact plate mounted, with tension spring loading, on an aluminum hub. The stator is mounted securely on a stationary object, which would ordinarily be the housing of a gear drive or a motor. The rotor is mounted on the shaft of the gear drive or motor. The commercial brake nominally operates in a fail-safe (in the sense of normally braking) mode: In the absence of current in the electromagnet coil, the permanent magnet pulls the contact plate, against the spring tension, into contact with the stator. To release the brake, one excites the electromagnet with a current of the magnitude and polarity chosen to cancel the magnetic flux of the permanent magnet, thereby enabling the spring tension to pull the contact plate out of contact with the stator. The fail-safe operation of the commercial brake depends on careful mounting of the rotor in relation to the stator. The rotor/stator gap must be set with a tolerance between 10 and 15 mils (between about 0.25 and about 0.38 mm). If the gap or the contact pad is thicker than the maximum allowable value, then the permanent magnetic field will not be strong enough to pull the steel plate across the gap. (For this reason, any contact pad between the contact plate and the stator must also be correspondingly thin.) If the gap exceeds the maximum allowable value because of shaft end play, it becomes impossible to set the brake by turning off the electromagnet current. Although it may
International Nuclear Information System (INIS)
Dodin, E.P.; Zharov, A.A.
2003-01-01
The effect of the strong high-frequency electromagnetic field on the lateral semiconductor superlattice is considered on the basis of the quasi-classical theory on the electron transport in the self-consistent wave arrangement. It is theoretically identified, that the lateral superlattice in the strong feed-up wave field may emit the terahertz radiation wave trains, which are associated with the periodical excitation of the Bloch oscillations in the superlattice. The conditions, required for the Bloch oscillators radiation observation, are determined. The spectral composition of the radiation, passing through the superlattice, and energy efficiency of multiplying the frequency, related to the Bloch oscillator excitation, are calculated [ru
Electromagnetic-gravitational conversion cross sections in external electromagnetic fields
International Nuclear Information System (INIS)
Hoang Ngoc Long; Dang Van Soa; Tuan Tran, A.
1994-09-01
The classical processes: the conversion of photons into gravitons in the static electromagnetic fields are considered by using Feynman perturbation techniques. The differential cross sections are presented for the conversion in the electric field of the flat condenser and the magnetic field of the solenoid. A numerical evaluation shows that the cross sections may have the observable value in the present technical scenario. (author). 11 refs
Advanced electromagnetics and scattering theory
2015-01-01
This book present the lecture notes used in two courses that the late Professor Kasra Barkeshli had offered at Sharif University of Technology, namely, Advanced Electromagnetics and Scattering Theory. The prerequisite for the sequence is vector calculus and electromagnetic fields and waves. Some familiarity with Green's functions and integral equations is desirable but not necessary. The book provides a brief but concise introduction to classical topics in the field. It is divided into three parts including annexes. Part I covers principle of electromagnetic theory. The discussion starts with a review of the Maxwell's equations in differential and integral forms and basic boundary conditions. The solution of inhomogeneous wave equation and various field representations including Lorentz's potential functions and the Green's function method are discussed next. The solution of Helmholtz equation and wave harmonics follow. Next, the book presents plane wave propagation in dielectric and lossy media and various...
International Nuclear Information System (INIS)
Tzeng, Wen-Shian V.
1991-01-01
Electromagnetic interference (EMI) shielding materials are well known in the art in forms such as gaskets, caulking compounds, adhesives, coatings and the like for a variety of EMI shielding purposes. In the past, where high shielding performance is necessary, EMI shielding has tended to use silver particles or silver coated copper particles dispersed in a resin binder. More recently, aluminum core silver coated particles have been used to reduce costs while maintaining good electrical and physical properties. (author). 8 figs
Energy Technology Data Exchange (ETDEWEB)
Aldridge, David F.
2014-11-01
A reciprocity theorem is an explicit mathematical relationship between two different wavefields that can exist within the same space - time configuration. Reciprocity theorems provi de the theoretical underpinning for mod ern full waveform inversion solutions, and also suggest practical strategies for speed ing up large - scale numerical modeling of geophysical datasets . In the present work, several previously - developed electromagnetic r eciprocity theorems are generalized to accommodate a broader range of medi um, source , and receiver types. Reciprocity relations enabling the interchange of various types of point sources and point receivers within a three - dimensional electromagnetic model are derived. Two numerical modeling algorithms in current use are successfully tested for adherence to reciprocity. Finally, the reciprocity theorem forms the point of departure for a lengthy derivation of electromagnetic Frechet derivatives. These mathe matical objects quantify the sensitivity of geophysical electromagnetic data to variatio ns in medium parameters, and thus constitute indispensable tools for solution of the full waveform inverse problem. ACKNOWLEDGEMENTS Sandia National Labor atories is a multi - program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the US Department of Energy's National Nuclear Security Administration under contract DE - AC04 - 94AL85000. Signif icant portions of the work reported herein were conducted under a Cooperative Research and Development Agreement (CRADA) between Sandia National Laboratories (SNL) and CARBO Ceramics Incorporated. The author acknowledges Mr. Chad Cannan and Mr. Terry Pa lisch of CARBO Ceramics, and Ms. Amy Halloran, manager of SNL's Geophysics and Atmospheric Sciences Department, for their interest in and encouragement of this work. Special thanks are due to Dr . Lewis C. Bartel ( recently retired from Sandia National Labo ratories
Ida, Nathan
2015-01-01
This book provides students with a thorough theoretical understanding of electromagnetic field equations and it also treats a large number of applications. The text is a comprehensive two-semester textbook. The work treats most topics in two steps – a short, introductory chapter followed by a second chapter with in-depth extensive treatment; between 10 to 30 applications per topic; examples and exercises throughout the book; experiments, problems and summaries. The new edition includes: updated end of chapter problems; a new introduction to electromagnetics based on behavior of charges; a new section on units; MATLAB tools for solution of problems and demonstration of subjects; most chapters include a summary. The book is an undergraduate textbook at the Junior level, intended for required classes in electromagnetics. It is written in simple terms with all details of derivations included and all steps in solutions listed. It requires little beyond basic calculus and can be used for self-study. The weal...
Hadronic processes and electromagnetic corrections
International Nuclear Information System (INIS)
Scimemi, I.
2004-01-01
The inclusion of electromagnetism in a low energy effective theory is worth further study in view of the present high precision experiments (muon g - 2, π 0 → γγ, τ decays, etc.). In particular in many applications of chiral perturbation theory, one has to purify physical matrix elements from electromagnetic effects. The theoretical problems that I want to point out here are following: the splitting of a pure QCD and a pure electromagnetic part in a hadronic process is model dependent: is it possible to parametrise in a clear way this splitting? What kind of information (scale dependence, gauge dependence,) is actually included in the parameters of the low energy effective theory? I will attempt to answer these questions introducing a possible convention to perform the splitting between strong and electromagnetic parts in some examples
On the paramagnetism of spin in the classical limit
International Nuclear Information System (INIS)
Hogreve, H.
1985-12-01
We consider particles with spin 1/2 in external electromagnetic fields. Although in many quantum mechanical situations they show a paramagnetic behaviour, within non-relativistic quantum theory a universal paramagnetic influence of spin fails to be true in general. Here we investigate the paramagnetism of spin in the framework of a classical theory. Applying previous results for the classical limit slash-h→O we obtain a classical expression corresponding to the quantum partition function of Hamiltonians with spin variables. For this classical partition function simple estimates lead to a paramagnetic inequality which demonstrates that indeed in the classical limit the spin shows a general paramagnetic behaviour. (author)
Electromagnetic radiation due to spacetime oscillations
International Nuclear Information System (INIS)
Chitre, D.M.; Price, R.H.; Sandberg, V.D.
1975-01-01
Wave equations are derived in the Newman-Penrose formalism for mixed electromagnetic and gravitational perturbations on both a flat spacetime background and a slightly charged (Q 2 very-much-less-than GM 2 ) Reissner-Nordstroem background. The physical meaning of these equations is discussed and analytical results are derived for nonrelativistic sources and for ultrarelativistic particle motions. The relationship between even-parity (TM) electromagnetic radiation multipoles in the long-wavelength approximation and static multipoles is shown to be the same as for classical radiation, suggesting a simple picture for electromagnetic radiation induced by gravitational perturbations
Electromagnetic potentials without gauge transformations
International Nuclear Information System (INIS)
Chubykalo, A; Espinoza, A; Alvarado Flores, R
2011-01-01
In this paper, we show that the use of the Helmholtz theorem enables the derivation of uniquely determined electromagnetic potentials without the necessity of using gauge transformation. We show that the electromagnetic field comprises two components, one of which is characterized by instantaneous action at a distance, whereas the other propagates in retarded form with the velocity of light. In our attempt to show the superiority of the new proposed method to the standard one, we argue that the action-at-a-distance components cannot be considered as a drawback of our method, because the recommended procedure for eliminating the action at a distance in the Coulomb gauge leads to theoretical subtleties that allow us to say that the needed gauge transformation is not guaranteed. One of the theoretical consequences of this new definition is that, in addition to the electric E and magnetic B fields, the electromagnetic potentials are real physical quantities. We show that this property of the electromagnetic potentials in quantum mechanics is also a property of the electromagnetic potentials in classical electrodynamics.
Electromagnetic processes in relativistic heavy ion collisions
International Nuclear Information System (INIS)
Bertulani, C.A.; Rio de Janeiro Univ.
1987-05-01
A study of the processes generated by the electromagnetic interaction in relativistic nuclear, and atomic collisions is presented. Very strong electromagnetic fields for a very short time are present in distant collisions with no nuclear contact. Such fields can also lead to interesting effects, which are discussed here. (orig.)
Compact X-ray sources. Simulating the electron/strong laser interaction
Energy Technology Data Exchange (ETDEWEB)
Hartin, Anthony [DESY, CFEL, Hamburg (Germany)
2016-07-01
The collision of an intense laser with an electron bunch can be used to produce X-rays via the inverse Compton scattering (ICS) mechanism. The ICS can be simulated via either a classical theory in which electrons and photons are treated in terms of classical electromagnetic waves - or a quantum theory in which charged particles interact with strong electromagnetic fields. The laser intensity used in a practical ICS collision is likely to be at such a level that quantum effects may be significant and the use of quantum theory may become a necessity. A simulation study is presented here comparing the classical and quantum approaches to the ICS. A custom particle-in-cell (PIC) software code, with photon generation by monte carlo of the exact quantum transition probability is used to simulate the quantum treatment. Peak resonant energies and the angular distribution of the X-rays are obtained and compared with those predicted by the classical theory. The conditions under which significant differences between the two theories emerges is obtained.
Electromagnetic scattering theory
Bird, J. F.; Farrell, R. A.
1986-01-01
Electromagnetic scattering theory is discussed with emphasis on the general stochastic variational principle (SVP) and its applications. The stochastic version of the Schwinger-type variational principle is presented, and explicit expressions for its integrals are considered. Results are summarized for scalar wave scattering from a classic rough-surface model and for vector wave scattering from a random dielectric-body model. Also considered are the selection of trial functions and the variational improvement of the Kirchhoff short-wave approximation appropriate to large size-parameters. Other applications of vector field theory discussed include a general vision theory and the analysis of hydromagnetism induced by ocean motion across the geomagnetic field. Levitational force-torque in the magnetic suspension of the disturbance compensation system (DISCOS), now deployed in NOVA satellites, is also analyzed using the developed theory.
Indian Academy of Sciences (India)
Journal of Genetics, Vol. 85, No. 2, August 2006. 101. Page 2. J. Genet. classic. 102. Journal of Genetics, Vol. 85, No. 2, August 2006. Page 3. J. Genet. classic. Journal of Genetics, Vol. 85, No. 2, August 2006. 103. Page 4. J. Genet. classic. 104. Journal of Genetics, Vol. 85, No. 2, August 2006. Page 5. J. Genet. classic.
Indian Academy of Sciences (India)
Unknown
Journal of Genetics, Vol. 84, No. 1, April 2005. 37. Page 2. J. Genet. classic. Journal of Genetics, Vol. 84, No. 1, April 2005. 38. Page 3. J. Genet. classic. Journal of Genetics, Vol. 84, No. 1, April 2005. 39. Page 4. J. Genet. classic. Journal of Genetics, Vol. 84, No. 1, April 2005. 40. Page 5. J. Genet. classic. Journal of ...
Metamaterials beyond electromagnetism
International Nuclear Information System (INIS)
Kadic, Muamer; Bückmann, Tiemo; Schittny, Robert; Wegener, Martin
2013-01-01
Metamaterials are rationally designed man-made structures composed of functional building blocks that are densely packed into an effective (crystalline) material. While metamaterials are mostly associated with negative refractive indices and invisibility cloaking in electromagnetism or optics, the deceptively simple metamaterial concept also applies to rather different areas such as thermodynamics, classical mechanics (including elastostatics, acoustics, fluid dynamics and elastodynamics), and, in principle, also to quantum mechanics. We review the basic concepts, analogies and differences to electromagnetism, and give an overview on the current state of the art regarding theory and experiment—all from the viewpoint of an experimentalist. This review includes homogeneous metamaterials as well as intentionally inhomogeneous metamaterial architectures designed by coordinate-transformation-based approaches analogous to transformation optics. Examples are laminates, transient thermal cloaks, thermal concentrators and inverters, ‘space-coiling’ metamaterials, anisotropic acoustic metamaterials, acoustic free-space and carpet cloaks, cloaks for gravitational surface waves, auxetic mechanical metamaterials, pentamode metamaterials (‘meta-liquids’), mechanical metamaterials with negative dynamic mass density, negative dynamic bulk modulus, or negative phase velocity, seismic metamaterials, cloaks for flexural waves in thin plates and three-dimensional elastostatic cloaks. (review article)
Metamaterials beyond electromagnetism
Kadic, Muamer; Bückmann, Tiemo; Schittny, Robert; Wegener, Martin
2013-12-01
Metamaterials are rationally designed man-made structures composed of functional building blocks that are densely packed into an effective (crystalline) material. While metamaterials are mostly associated with negative refractive indices and invisibility cloaking in electromagnetism or optics, the deceptively simple metamaterial concept also applies to rather different areas such as thermodynamics, classical mechanics (including elastostatics, acoustics, fluid dynamics and elastodynamics), and, in principle, also to quantum mechanics. We review the basic concepts, analogies and differences to electromagnetism, and give an overview on the current state of the art regarding theory and experiment—all from the viewpoint of an experimentalist. This review includes homogeneous metamaterials as well as intentionally inhomogeneous metamaterial architectures designed by coordinate-transformation-based approaches analogous to transformation optics. Examples are laminates, transient thermal cloaks, thermal concentrators and inverters, ‘space-coiling’ metamaterials, anisotropic acoustic metamaterials, acoustic free-space and carpet cloaks, cloaks for gravitational surface waves, auxetic mechanical metamaterials, pentamode metamaterials (‘meta-liquids’), mechanical metamaterials with negative dynamic mass density, negative dynamic bulk modulus, or negative phase velocity, seismic metamaterials, cloaks for flexural waves in thin plates and three-dimensional elastostatic cloaks.
Lagrangian formulation of classical BMT-theory
International Nuclear Information System (INIS)
Pupasov-Maksimov, Andrey; Deriglazov, Alexei; Guzman, Walberto
2013-01-01
Full text: The most popular classical theory of electron has been formulated by Bargmann, Michel and Telegdi (BMT) in 1959. The BMT equations give classical relativistic description of a charged particle with spin and anomalous magnetic momentum moving in homogeneous electro-magnetic field. This allows to study spin dynamics of polarized beams in uniform fields. In particular, first experimental measurements of muon anomalous magnetic momentum were done using changing of helicity predicted by BMT equations. Surprisingly enough, a systematic formulation and the analysis of the BMT theory are absent in literature. In the present work we particularly fill this gap by deducing Lagrangian formulation (variational problem) for BMT equations. Various equivalent forms of Lagrangian will be discussed in details. An advantage of the obtained classical model is that the Lagrangian action describes a relativistic spinning particle without Grassmann variables, for both free and interacting cases. This implies also the possibility of canonical quantization. In the interacting case, an arbitrary electromagnetic background may be considered, which generalizes the BMT theory formulated to the case of homogeneous fields. The classical model has two local symmetries, which gives an interesting example of constrained classical dynamics. It is surprising, that the case of vanishing anomalous part of the magnetic momentum is naturally highlighted in our construction. (author)
Electromagnetic field computation by network methods
Felsen, Leopold B; Russer, Peter
2009-01-01
This monograph proposes a systematic and rigorous treatment of electromagnetic field representations in complex structures. The book presents new strong models by combining important computational methods. This is the last book of the late Leopold Felsen.
Special relativity and classical field theory
Susskind, Leonard
2017-01-01
Physicist Leonard Susskind and data engineer Art Friedman are back. This time, they introduce readers to Einstein's special relativity and Maxwell's classical field theory. Using their typical brand of real math, enlightening drawings, and humor, Susskind and Friedman walk us through the complexities of waves, forces, and particles by exploring special relativity and electromagnetism. It's a must-read for both devotees of the series and any armchair physicist who wants to improve their knowledge of physics' deepest truths.
Classical resonances and quantum scarring
International Nuclear Information System (INIS)
Manderfeld, Christopher
2003-01-01
We study the correspondence between phase-space localization of quantum (quasi-)energy eigenstates and classical correlation decay, given by Ruelle-Pollicott resonances of the Frobenius-Perron operator. It will be shown that scarred (quasi-)energy eigenstates are correlated: pairs of eigenstates strongly overlap in phase space (scar in same phase-space regions) if the difference of their eigenenergies is close to the phase of a leading classical resonance. Phase-space localization of quantum states will be measured by L 2 norms of their Husimi functions
Nonlinear interaction of charged particles with strong laser pulses in a gaseous media
Directory of Open Access Journals (Sweden)
H. K. Avetissian
2007-07-01
Full Text Available The charged particles nonlinear dynamics in the field of a strong electromagnetic wave pulse of finite duration and certain form of the envelope, in the refractive medium with a constant and variable refraction indexes, is investigated by means of numerical integration of the classical relativistic equations of motion. The particle energy dependence on the pulse intensity manifests the nonlinear threshold phenomenon of a particle reflection and capture by actual laser pulses in dielectric-gaseous media that takes place for a plane electromagnetic wave in the induced Cherenkov process. Laser acceleration of the particles in the result of the reflection from the pulse envelope and in the capture regime with the variable refraction index along the pulse propagation direction is investigated.
Bettini, Alessandro
This first volume covers the mechanics of point particles, gravitation, extended systems (starting from the two-body system), the basic concepts of relativistic mechanics and the mechanics of rigid bodies and fluids. The four-volume textbook, which covers electromagnetism, mechanics, fluids and thermodynamics, and waves and light, is designed to reflect the typical syllabus during the first two years of a calculus-based university physics program. Throughout all four volumes, particular attention is paid to in-depth clarification of conceptual aspects, and to this end the historical roots of the principal concepts are traced. Writings by the founders of classical mechanics, G. Galilei and I. Newton, are reproduced, encouraging students to consult them. Emphasis is also consistently placed on the experimental basis of the concepts, highlighting the experimental nature of physics. Whenever feasible at the elementary level, concepts relevant to more advanced courses in modern physics are included. Each chapter b...
On causal nonrelativistic classical electrodynamics
International Nuclear Information System (INIS)
Goedecke, G.H.
1984-01-01
The differential-difference (DD) motion equations of the causal nonrelativistic classical electrodynamics developed by the author in 1975 are shown to possess only nonrunaway, causal solutions with no discontinuities in particle velocity or position. As an example, the DD equation solution for the problem of an electromagnetic shock incident on an initially stationary charged particle is contrasted with the standard Abraham-Lorentz equation solution. The general Cauchy problem for these DD motion equations is discussed. In general, in order to uniquely determine a solution, the initial data must be more detailed than the standard Cauchy data of initial position and velocity. Conditions are given under which the standard Cauchy data will determine the DD equation solutions to sufficient practical accuracy
Electromagnetic Saturation of Angstrom-Sized Quantum Barriers at Terahertz Frequencies
Bahk, Young-Mi; Kang, Bong Joo; Kim, Yong Seung; Kim, Joon-Yeon; Kim, Won Tae; Kim, Tae Yun; Kang, Taehee; Rhie, Jiyeah; Han, Sanghoon; Park, Cheol-Hwan; Rotermund, Fabian; Kim, Dai-Sik
2015-09-01
Metal-graphene-metal hybrid structures allow angstrom-scale van der Waals gaps, across which electron tunneling occurs. We squeeze terahertz electromagnetic waves through these λ /10 000 000 gaps, accompanied by giant field enhancements. Unprecedented transmission reduction of 97% is achieved with the transient voltage across the gap saturating at 5 V. Electron tunneling facilitated by the transient electric field strongly modifies the gap index, starting a self-limiting process related to the barrier height. Our work enables greater interplay between classical optics and quantum tunneling, and provides optical indices to the van der Waals gaps.
Electromagnetic Saturation of Angstrom-Sized Quantum Barriers at Terahertz Frequencies.
Bahk, Young-Mi; Kang, Bong Joo; Kim, Yong Seung; Kim, Joon-Yeon; Kim, Won Tae; Kim, Tae Yun; Kang, Taehee; Rhie, Jiyeah; Han, Sanghoon; Park, Cheol-Hwan; Rotermund, Fabian; Kim, Dai-Sik
2015-09-18
Metal-graphene-metal hybrid structures allow angstrom-scale van der Waals gaps, across which electron tunneling occurs. We squeeze terahertz electromagnetic waves through these λ/10 000 000 gaps, accompanied by giant field enhancements. Unprecedented transmission reduction of 97% is achieved with the transient voltage across the gap saturating at 5 V. Electron tunneling facilitated by the transient electric field strongly modifies the gap index, starting a self-limiting process related to the barrier height. Our work enables greater interplay between classical optics and quantum tunneling, and provides optical indices to the van der Waals gaps.
Chabert, P.
2007-02-01
In plasma processing, capacitive discharges have classically been operated in the electrostatic regime, for which the excitation wavelength λ is much greater than the electrode radius, and the plasma skin depth δ is much greater than the electrode spacing. However, contemporary reactors are larger and excited at higher frequencies which leads to strong electromagnetic effects. This paper gives a review of the work that has recently been carried out to carefully model and diagnose these effects, which cause major uniformity problems in plasma processing for microelectronics and flat panel displays industries.
Dynamics of ionisation and entanglement in the 'atom + quantum electromagnetic field' system
Energy Technology Data Exchange (ETDEWEB)
Sharapova, P R; Tikhonova, O V [Department of Physics, M.V. Lomonosov Moscow State University (Russian Federation)
2012-03-31
The dynamics of a model Rydberg atom in a strong nonclassical electromagnetic field is investigated. The field-induced transitions to the continuum involving different numbers of photons (with intermediate states in the discrete spectrum) are taken into account and the specific features of ionisation in 'squeezed' field states are considered in comparison with the case of classical light. A significant decrease in the ionisation rate is found, which is caused by the interference stabilisation of the atomic system. The entanglement of the atomic and field subsystems, the temporal dynamics of the correlations found, and the possibility of measuring them are analysed.
Electromagnetic effects in high-frequency capacitive discharges used for plasma processing
International Nuclear Information System (INIS)
Chabert, P
2007-01-01
In plasma processing, capacitive discharges have classically been operated in the electrostatic regime, for which the excitation wavelength λ is much greater than the electrode radius, and the plasma skin depth δ is much greater than the electrode spacing. However, contemporary reactors are larger and excited at higher frequencies which leads to strong electromagnetic effects. This paper gives a review of the work that has recently been carried out to carefully model and diagnose these effects, which cause major uniformity problems in plasma processing for microelectronics and flat panel displays industries. (topical review)
Electromagnetic topology: Characterization of internal electromagnetic coupling
Parmantier, J. P.; Aparicio, J. P.; Faure, F.
1991-01-01
The main principles are presented of a method dealing with the resolution of electromagnetic internal problems: Electromagnetic Topology. A very interesting way is to generalize the multiconductor transmission line network theory to the basic equation of the Electromagnetic Topology: the BLT equation. This generalization is illustrated by the treatment of an aperture as a four port junction. Analytical and experimental derivations of the scattering parameters are presented. These concepts are used to study the electromagnetic coupling in a scale model of an aircraft, and can be seen as a convenient means to test internal electromagnetic interference.
Energy flow in a bound electromagnetic field: resolution of apparent paradoxes
International Nuclear Information System (INIS)
Kholmetskii, A L; Yarman, T
2008-01-01
In this paper, we present a resolution of apparent paradoxes formulated in (Kholmetskii A L 2006 Apparent paradoxes in classical electrodynamics: the energy-momentum conservation law for a bound electromagnetic field Eur. J. Phys. 27 825-38; Kholmetskii A L and Yarman T 2008 Apparent paradoxes in classical electrodynamics: a fluid medium in an electromagnetic field Eur. J. Phys. 29 1127) and dealing with the energy flux in a bound electromagnetic field
Electromagnetically shielded building
International Nuclear Information System (INIS)
Takahashi, T.; Nakamura, M.; Yabana, Y.; Ishikawa, T.; Nagata, K.
1992-01-01
This invention relates to a building having an electromagnetic shield structure well-suited for application to an information network system utilizing electromagnetic waves, and more particularly to an electromagnetically shielded building for enhancing the electromagnetic shielding performance of an external wall. 6 figs
Electromagnetically shielded building
Energy Technology Data Exchange (ETDEWEB)
Takahashi, T; Nakamura, M; Yabana, Y; Ishikawa, T; Nagata, K
1992-04-21
This invention relates to a building having an electromagnetic shield structure well-suited for application to an information network system utilizing electromagnetic waves, and more particularly to an electromagnetically shielded building for enhancing the electromagnetic shielding performance of an external wall. 6 figs.
Beta Decay in the Field of an Electromagnetic Wave and Experiments on Measuring the Neutrino Mass
International Nuclear Information System (INIS)
Dorofeev, O.F.; Lobanov, A.E.
2005-01-01
Investigations of the effect of an electromagnetic wave field on the beta-decay process are used to analyze the tritium-decay experimental data on the neutrino mass. It is shown that the electromagnetic wave can distort the beta spectrum, shifting the end point to the higher energy region. This phenomenon is purely classical and it is associated with the electron acceleration in the radiation field. Since strong magnetic fields exist in setups for precise measurement of the neutrino mass, the indicated field can appear owing to the synchrotron radiation mechanism. The phenomenon under consideration can explain the experimentally observed anomalies in the spectrum of the decay electrons; in particular, the effect of the 'negative square of the neutrino mass'
Classical and non-classical effective medium theories: New perspectives
Energy Technology Data Exchange (ETDEWEB)
Tsukerman, Igor, E-mail: igor@uakron.edu
2017-05-18
Highlights: • Advanced non-asymptotic and nonlocal homogenization theories of metamaterials, valid in electrostatics and electrodynamics. • Classical theories (Clausius–Mossotti, Lorenz–Lorentz, Maxwell Garnett) fit well into the proposed framework. • Nonlocal effects can be included in the model, making order-of-magnitude accuracy improvements possible. • A challenging problem for future research is to determine what effective tensors are attainable for given constituents of a metamaterial. - Abstract: Future research in electrodynamics of periodic electromagnetic composites (metamaterials) can be expected to produce sophisticated homogenization theories valid for any composition and size of the lattice cell. The paper outlines a promising path in that direction, leading to non-asymptotic and nonlocal homogenization models, and highlights aspects of homogenization that are often overlooked: the finite size of the sample and the role of interface boundaries. Classical theories (e.g. Clausius–Mossotti, Maxwell Garnett), while originally derived from a very different set of ideas, fit well into the proposed framework. Nonlocal effects can be included in the model, making an order-of-magnitude accuracy improvements possible. One future challenge is to determine what effective parameters can or cannot be obtained for a given set of constituents of a metamaterial lattice cell, thereby delineating the possible from the impossible in metamaterial design.
Classical and non-classical effective medium theories: New perspectives
International Nuclear Information System (INIS)
Tsukerman, Igor
2017-01-01
Highlights: • Advanced non-asymptotic and nonlocal homogenization theories of metamaterials, valid in electrostatics and electrodynamics. • Classical theories (Clausius–Mossotti, Lorenz–Lorentz, Maxwell Garnett) fit well into the proposed framework. • Nonlocal effects can be included in the model, making order-of-magnitude accuracy improvements possible. • A challenging problem for future research is to determine what effective tensors are attainable for given constituents of a metamaterial. - Abstract: Future research in electrodynamics of periodic electromagnetic composites (metamaterials) can be expected to produce sophisticated homogenization theories valid for any composition and size of the lattice cell. The paper outlines a promising path in that direction, leading to non-asymptotic and nonlocal homogenization models, and highlights aspects of homogenization that are often overlooked: the finite size of the sample and the role of interface boundaries. Classical theories (e.g. Clausius–Mossotti, Maxwell Garnett), while originally derived from a very different set of ideas, fit well into the proposed framework. Nonlocal effects can be included in the model, making an order-of-magnitude accuracy improvements possible. One future challenge is to determine what effective parameters can or cannot be obtained for a given set of constituents of a metamaterial lattice cell, thereby delineating the possible from the impossible in metamaterial design.
DEFF Research Database (Denmark)
Katajainen, Jyrki
2008-01-01
In this project the goal is to develop the safe * family of containers for the CPH STL. The containers to be developed should be safer and more reliable than any of the existing implementations. A special focus should be put on strong exception safety since none of the existing prototypes available...
Indian Academy of Sciences (India)
Unknown
Journal of Genetics, Vol. 83, No. 3, December 2004. 235. Page 2. J. Genet. classic. Journal of Genetics, Vol. 83, No. 3, December 2004. 236. Page 3. J. Genet. classic. Journal of Genetics, Vol. 83, No. 3, December 2004. 237. Page 4. J. Genet. classic. Journal of Genetics, Vol. 83, No. 3, December 2004. 238. Page 5 ...
Kolm, H.; Mongeau, P.; Williams, F.
1980-09-01
Recent advances in energy storage, switching and magnet technology make electromagnetic acceleration a viable alternative to chemical propulsion for certain tasks, and a means to perform other tasks not previously feasible. Applications include the acceleration of gram-size particles for hypervelocity research and the initiation of fusion by impact, a replacement for chemically propelled artillery, the transportation of cargo and personnel over inaccessible terrain, and the launching of space vehicles to supply massive space operations, and for the disposal of nuclear waste. The simplest launcher of interest is the railgun, in which a short-circuit slide or an arc is driven along two rails by direct current. The most sophisticated studied thus far is the mass driver, in which a superconducting shuttle bucket is accelerated by a line of pulse coils energized by capacitors at energy conversion efficiencies better than 90%. Other accelerators of interest include helical, brush-commutated motors, discrete coil arc commutated drivers, flux compression momentum transformers, and various hybrid electrochemical devices.
Topological Foundations of Electromagnetism
Barrett, Terrence W
2008-01-01
Topological Foundations of Electromagnetism seeks a fundamental understanding of the dynamics of electromagnetism; and marshals the evidence that in certain precisely defined topological conditions, electromagnetic theory (Maxwell's theory) must be extended or generalized in order to provide an explanation and understanding of, until now, unusual electromagnetic phenomena. Key to this generalization is an understanding of the circumstances under which the so-called A potential fields have physical effects. Basic to the approach taken is that the topological composition of electromagnetic field
International Nuclear Information System (INIS)
Froissart, Marcel
1976-01-01
Strong interactions are introduced by their more obvious aspect: nuclear forces. In hadron family, the nucleon octet, OMEGA - decuplet, and quark triply are successively considered. Pion wave having been put at the origin of nuclear forces, low energy phenomena are described, the force being explained as an exchange of structure corresponding to a Regge trajectory in a variable rotating state instead of the exchange of a well defined particle. At high energies the concepts of pomeron, parton and stratons are introduced, pionization and fragmentation are briefly differentiated [fr
Atom ionization in a nonclassical intense electromagnetic field
International Nuclear Information System (INIS)
Popov, A.M.; Tikhonova, O.V.
2002-01-01
The atoms ionization process in the intense nonclassical electromagnetic field is considered. It is shown that depending on the field quantum state the probability of ionization may essentially change even by one and the same average quantum number in the radiation mode, whereby the difference in the ionization rates is especially significant in the case, when the ionization process is of a multiphoton character. It is demonstrates in particular, that the nonclassical field may be considerably more intensive from the viewpoint of the atoms ionization, than the classical field with the same intensity. The peculiarities of the decay, related to the atomic system state in the strong nonclassical field beyond the perturbation theory frames are studied [ru
Relativistic classical strings. II
International Nuclear Information System (INIS)
Galvao, C.A.P.
1985-01-01
The interactions of strings with electromagnetic and gravitational fields are extensively discussed. Some concepts of differential geometry are reviewed. Strings in Kaluza-Klein manifolds are studied. (L.C.) [pt
Casimir effect: The classical limit
International Nuclear Information System (INIS)
Feinberg, J.; Mann, A.; Revzen, M.
2001-01-01
We analyze the high temperature (or classical) limit of the Casimir effect. A useful quantity which arises naturally in our discussion is the 'relative Casimir energy', which we define for a configuration of disjoint conducting boundaries of arbitrary shapes, as the difference of Casimir energies between the given configuration and a configuration with the same boundaries infinitely far apart. Using path integration techniques, we show that the relative Casimir energy vanishes exponentially fast in temperature. This is consistent with a simple physical argument based on Kirchhoff's law. As a result the 'relative Casimir entropy', which we define in an obviously analogous manner, tends, in the classical limit, to a finite asymptotic value which depends only on the geometry of the boundaries. Thus the Casimir force between disjoint pieces of the boundary, in the classical limit, is entropy driven and is governed by a dimensionless number characterizing the geometry of the cavity. Contributions to the Casimir thermodynamical quantities due to each individual connected component of the boundary exhibit logarithmic deviations in temperature from the behavior just described. These logarithmic deviations seem to arise due to our difficulty to separate the Casimir energy (and the other thermodynamical quantities) from the 'electromagnetic' self-energy of each of the connected components of the boundary in a well defined manner. Our approach to the Casimir effect is not to impose sharp boundary conditions on the fluctuating field, but rather take into consideration its interaction with the plasma of 'charge carriers' in the boundary, with the plasma frequency playing the role of a physical UV cutoff. This also allows us to analyze deviations from a perfect conductor behavior
Quantum fermions and quantum field theory from classical statistics
International Nuclear Information System (INIS)
Wetterich, Christof
2012-01-01
An Ising-type classical statistical ensemble can describe the quantum physics of fermions if one chooses a particular law for the time evolution of the probability distribution. It accounts for the time evolution of a quantum field theory for Dirac particles in an external electromagnetic field. This yields in the non-relativistic one-particle limit the Schrödinger equation for a quantum particle in a potential. Interference or tunneling arise from classical probabilities.
The semi classical laser theory and some applications of laser
International Nuclear Information System (INIS)
Abdalla, Abbaker Ali
1995-04-01
The semi classical laser theory is concerned with the interaction between light and matter in such a way that the matter is treated quantum-mechanically whereas light is treated in terms of the classical electromagnetic equations. In this work the Maxwell-Bloch equations are employed to describe the interaction between light and matter. Applications of the theory as well as different types of lasers are reviewed. (Author)
Classicality in quantum mechanics
International Nuclear Information System (INIS)
Dreyer, Olaf
2007-01-01
In this article we propose a solution to the measurement problem in quantum mechanics. We point out that the measurement problem can be traced to an a priori notion of classicality in the formulation of quantum mechanics. If this notion of classicality is dropped and instead classicality is defined in purely quantum mechanical terms the measurement problem can be avoided. We give such a definition of classicality. It identifies classicality as a property of large quantum system. We show how the probabilistic nature of quantum mechanics is a result of this notion of classicality. We also comment on what the implications of this view are for the search of a quantum theory of gravity
Classicality in quantum mechanics
Energy Technology Data Exchange (ETDEWEB)
Dreyer, Olaf [Theoretical Physics, Blackett Laboratory, Imperial College London, London, SW7 2AZ (United Kingdom)
2007-05-15
In this article we propose a solution to the measurement problem in quantum mechanics. We point out that the measurement problem can be traced to an a priori notion of classicality in the formulation of quantum mechanics. If this notion of classicality is dropped and instead classicality is defined in purely quantum mechanical terms the measurement problem can be avoided. We give such a definition of classicality. It identifies classicality as a property of large quantum system. We show how the probabilistic nature of quantum mechanics is a result of this notion of classicality. We also comment on what the implications of this view are for the search of a quantum theory of gravity.
Scaling, scattering, and blackbody radiation in classical physics
International Nuclear Information System (INIS)
Boyer, Timothy H
2017-01-01
Here we discuss blackbody radiation within the context of classical theory. We note that nonrelativistic classical mechanics and relativistic classical electrodynamics have contrasting scaling symmetries which influence the scattering of radiation. Also, nonrelativistic mechanical systems can be accurately combined with relativistic electromagnetic radiation only provided the nonrelativistic mechanical systems are the low-velocity limits of fully relativistic systems. Application of the no-interaction theorem for relativistic systems limits the scattering mechanical systems for thermal radiation to relativistic classical electrodynamic systems, which involve the Coulomb potential. Whereas the naive use of nonrelativistic scatterers or nonrelativistic classical statistical mechanics leads to the Rayleigh–Jeans spectrum, the use of fully relativistic scatterers leads to the Planck spectrum for blackbody radiation within classical physics. (paper)
Classical, Semi-classical and Quantum Noise
Poor, H; Scully, Marlan
2012-01-01
David Middleton was a towering figure of 20th Century engineering and science and one of the founders of statistical communication theory. During the second World War, the young David Middleton, working with Van Fleck, devised the notion of the matched filter, which is the most basic method used for detecting signals in noise. Over the intervening six decades, the contributions of Middleton have become classics. This collection of essays by leading scientists, engineers and colleagues of David are in his honor and reflect the wide influence that he has had on many fields. Also included is the introduction by Middleton to his forthcoming book, which gives a wonderful view of the field of communication, its history and his own views on the field that he developed over the past 60 years. Focusing on classical noise modeling and applications, Classical, Semi-Classical and Quantum Noise includes coverage of statistical communication theory, non-stationary noise, molecular footprints, noise suppression, Quantum e...
Classical and semiclassical aspects of chemical dynamics
International Nuclear Information System (INIS)
Gray, S.K.
1982-08-01
Tunneling in the unimolecular reactions H 2 C 2 → HC 2 H, HNC → HCN, and H 2 CO → H 2 + CO is studied with a classical Hamiltonian that allows the reaction coordinate and transverse vibrational modes to be considered directly. A combination of classical perturbation theory and the semiclassical WKB method allows tunneling probabilities to be obtained, and a statistical theory (RRKM) is used to construct rate constants for these reactions in the tunneling regime. In this fashion, it is found that tunneling may be important, particularly for low excitation energies. Nonadiabatic charge transfer in the reaction Na + I → Na + + I - is treated with classical trajectories based on a classical Hamiltonian that is the analogue of a quantum matrix representation. The charge transfer cross section obtained is found to agree reasonably well with the exact quantum results. An approximate semiclassical formula, valid at high energies, is also obtained. The interaction of radiation and matter is treated from a classical viewpoint. The excitation of an HF molecule in a strong laser is described with classical trajectories. Quantum mechanical results are also obtained and compared to the classical results. Although the detailed structure of the pulse time averaged energy absorption cannot be reproduced classically, classical mechanics does predict the correct magnitude of energy absorption, as well as certain other qualitative features. The classical behavior of a nonrotating diatomic molecule in a strong laser field is considered further, by generating a period advance map that allows the solution over many periods of oscillation of the laser to be obtained with relative ease. Classical states are found to form beautiful spirals in phase space as time progresses. A simple pendulum model is found to describe the major qualitative features
Solved problems in electromagnetics
Salazar Bloise, Félix; Bayón Rojo, Ana; Gascón Latasa, Francisco
2017-01-01
This book presents the fundamental concepts of electromagnetism through problems with a brief theoretical introduction at the beginning of each chapter. The present book has a strong didactic character. It explains all the mathematical steps and the theoretical concepts connected with the development of the problem. It guides the reader to understand the employed procedures to learn to solve the exercises independently. The exercises are structured in a similar way: The chapters begin with easy problems increasing progressively in the level of difficulty. This book is written for students of physics and engineering in the framework of the new European Plans of Study for Bachelor and Master and also for tutors and lecturers. .
Geomagnetic oriented electromagnetic radiation in the ionosphere
International Nuclear Information System (INIS)
Benton, C.U.; Fowles, H.M.; Goen, P.K.
1976-08-01
Strong bursts of electromagnetic radiation were observed in the ionosphere during the Waso rocket Electromagnetic Pulse (EMP) experiment. The pulses have a frequency content from below 20 MHz to above 70 MHz. They vary in duration between 5 μs and 2 ms and in peak-amplitudes of 2 mV/m to greater than 200 mV/m. These pulses show a high degree of geomagnetic correlation and are of unknown origin
Intermediate energy electromagnetic interactions
International Nuclear Information System (INIS)
Garcon, M.
1994-11-01
Polarization measurements in electromagnetic interactions are reviewed. Deep inelastic scattering of polarized electrons and muons an polarized targets, photoproduction of pseudoscalar mesons on protons, photonuclear reactions, and the electromagnetic structure of the deuteron are discussed. (K.A.)
Intermediate energy electromagnetic interactions
Energy Technology Data Exchange (ETDEWEB)
Garcon, M.
1994-11-01
Polarization measurements in electromagnetic interactions are reviewed. Deep inelastic scattering of polarized electrons and muons an polarized targets, photoproduction of pseudoscalar mesons on protons, photonuclear reactions, and the electromagnetic structure of the deuteron are discussed. (K.A.).
Electromagnetic wave matching device
International Nuclear Information System (INIS)
Hirata, Yosuke; Mitsunaka, Yoshika; Hayashi, Ken-ichi; Ito, Yasuyuki.
1997-01-01
The present invention provides an electromagnetic wave matching capable of reducing a cost for the transmission system in a system of using electromagnetic waves for plasma heating of a thermonuclear reactor. Namely, incident electromagnetic waves are reflected by using a plurality of phase correction mirrors. The reflected electromagnetic waves are connected to an external transmission system through an exit. The phase correction mirrors have such a shape to receive a plurality of beam-like electromagnetic waves and output electromagnetic waves by the number different from the number of the received electromagnetic wave beams having a predetermined distribution. Further, at least two of the phase correction mirrors have such a shape to change the phase of the electromagnetic waves beams incident to the reflection surface of the phase correction mirrors by a predetermined amount corresponding to the position of the reflection surface. Then, the cost for transmission system can greatly be reduced. (I.S.)
Broadband electromagnetic analysis of compacted kaolin
International Nuclear Information System (INIS)
Bore, Thierry; Scheuermann, Alexander; Wagner, Norman; Cai, Caifang
2017-01-01
The mechanical compaction of soil influences not only the mechanical strength and compressibility but also the hydraulic behavior in terms of hydraulic conductivity and soil suction. At the same time, electric and dielectric parameters are increasingly used to characterize soil and to relate them with mechanic and hydraulic parameters. In the presented study electromagnetic soil properties and suction were measured under defined conditions of standardized compaction tests. The impact of external mechanical stress conditions of nearly pure kaolinite was analyzed on soil suction and broadband electromagnetic soil properties. An experimental procedure was developed and validated to simultaneously determine mechanical, hydraulic and broadband (1 MHz–3 GHz) electromagnetic properties of the porous material. The frequency dependent electromagnetic properties were modeled with a classical mixture equation (advanced Lichtenecker and Rother model, ALRM) and a hydraulic-mechanical-electromagnetic coupling approach was introduced considering water saturation, soil structure (bulk density, porosity), soil suction (pore size distribution, water sorption) as well as electrical conductivity of the aqueous pore solution. Moreover, the relaxation behavior was analyzed with a generalized fractional relaxation model concerning a high-frequency water process and two interface processes extended with an apparent direct current conductivity contribution. The different modeling approaches provide a satisfactory agreement with experimental data for the real part. These results show the potential of broadband electromagnetic approaches for quantitative estimation of the hydraulic state of the soil during densification. (paper)
International Nuclear Information System (INIS)
Shvets, G.; Tushentsov, M.; Tokman, M.D.; Kryachko, A.
2005-01-01
Propagation of electromagnetic waves in magnetized plasma near the electron cyclotron frequency can be strongly modified by adding a weak magnetic undulator. For example, both right- and left-hand circularly polarized waves can propagate along the magnetic field without experiencing resonant absorption. This effect of entirely eliminating electron cyclotron heating is referred to as the undulator-induced transparency (UIT) of the plasma, and is the classical equivalent of the well-known quantum mechanical effect of electromagnetically induced transparency. The basics of UIT are reviewed, and various ways in which UIT can be utilized to achieve exotic propagation properties of electromagnetic waves in plasmas are discussed. For example, UIT can dramatically slow down the waves' group velocity, resulting in the extreme compression of the wave energy in the plasma. Compressed waves are polarized along the propagation direction, and can be used for synchronous electron or ion acceleration. Strong coupling between the two wave helicities are explored to impart the waves with high group velocities ∂ω/∂k for vanishing wave numbers k. Cross-helicity coupling for realistic density and magnetic field profiles are examined using a linearized fluid code, particle-in-cell simulations, and ray-tracing WKB calculations
Quantum Models of Classical World
Directory of Open Access Journals (Sweden)
Petr Hájíček
2013-02-01
Full Text Available This paper is a review of our recent work on three notorious problems of non-relativistic quantum mechanics: realist interpretation, quantum theory of classical properties, and the problem of quantum measurement. A considerable progress has been achieved, based on four distinct new ideas. First, objective properties are associated with states rather than with values of observables. Second, all classical properties are selected properties of certain high entropy quantum states of macroscopic systems. Third, registration of a quantum system is strongly disturbed by systems of the same type in the environment. Fourth, detectors must be distinguished from ancillas and the states of registered systems are partially dissipated and lost in the detectors. The paper has two aims: a clear explanation of all new results and a coherent and contradiction-free account of the whole quantum mechanics including all necessary changes of its current textbook version.
Classical spins in superconductors
Energy Technology Data Exchange (ETDEWEB)
Shiba, H [Tokyo Univ.; Maki, K
1968-08-01
It is shown that there exists a localized excited state in the energy gap in a superconductor with a classical spin. At finite concentration localized excited states around classical spins form an impurity band. The process of growth of the impurity band and its effects on observable quantities are investigated.
Valley, Lois
1989-01-01
The SPS product, Classic-Ada, is a software tool that supports object-oriented Ada programming with powerful inheritance and dynamic binding. Object Oriented Design (OOD) is an easy, natural development paradigm, but it is not supported by Ada. Following the DOD Ada mandate, SPS developed Classic-Ada to provide a tool which supports OOD and implements code in Ada. It consists of a design language, a code generator and a toolset. As a design language, Classic-Ada supports the object-oriented principles of information hiding, data abstraction, dynamic binding, and inheritance. It also supports natural reuse and incremental development through inheritance, code factoring, and Ada, Classic-Ada, dynamic binding and static binding in the same program. Only nine new constructs were added to Ada to provide object-oriented design capabilities. The Classic-Ada code generator translates user application code into fully compliant, ready-to-run, standard Ada. The Classic-Ada toolset is fully supported by SPS and consists of an object generator, a builder, a dictionary manager, and a reporter. Demonstrations of Classic-Ada and the Classic-Ada Browser were given at the workshop.
Fermions from classical statistics
International Nuclear Information System (INIS)
Wetterich, C.
2010-01-01
We describe fermions in terms of a classical statistical ensemble. The states τ of this ensemble are characterized by a sequence of values one or zero or a corresponding set of two-level observables. Every classical probability distribution can be associated to a quantum state for fermions. If the time evolution of the classical probabilities p τ amounts to a rotation of the wave function q τ (t)=±√(p τ (t)), we infer the unitary time evolution of a quantum system of fermions according to a Schroedinger equation. We establish how such classical statistical ensembles can be mapped to Grassmann functional integrals. Quantum field theories for fermions arise for a suitable time evolution of classical probabilities for generalized Ising models.
Quantum computation with classical light: The Deutsch Algorithm
International Nuclear Information System (INIS)
Perez-Garcia, Benjamin; Francis, Jason; McLaren, Melanie; Hernandez-Aranda, Raul I.; Forbes, Andrew; Konrad, Thomas
2015-01-01
We present an implementation of the Deutsch Algorithm using linear optical elements and laser light. We encoded two quantum bits in form of superpositions of electromagnetic fields in two degrees of freedom of the beam: its polarisation and orbital angular momentum. Our approach, based on a Sagnac interferometer, offers outstanding stability and demonstrates that optical quantum computation is possible using classical states of light. - Highlights: • We implement the Deutsh Algorithm using linear optical elements and classical light. • Our qubits are encoded in the polarisation and orbital angular momentum of the beam. • We show that it is possible to achieve quantum computation with two qubits in the classical domain of light
Quantum computation with classical light: The Deutsch Algorithm
Energy Technology Data Exchange (ETDEWEB)
Perez-Garcia, Benjamin [Photonics and Mathematical Optics Group, Tecnológico de Monterrey, Monterrey 64849 (Mexico); University of the Witwatersrand, Private Bag 3, Johannesburg 2050 (South Africa); Francis, Jason [School of Chemistry and Physics, University of KwaZulu-Natal, Private Bag X54001, Durban 4000 (South Africa); McLaren, Melanie [University of the Witwatersrand, Private Bag 3, Johannesburg 2050 (South Africa); Hernandez-Aranda, Raul I. [Photonics and Mathematical Optics Group, Tecnológico de Monterrey, Monterrey 64849 (Mexico); Forbes, Andrew [University of the Witwatersrand, Private Bag 3, Johannesburg 2050 (South Africa); Konrad, Thomas, E-mail: konradt@ukzn.ac.za [School of Chemistry and Physics, University of KwaZulu-Natal, Private Bag X54001, Durban 4000 (South Africa); National Institute of Theoretical Physics, Durban Node, Private Bag X54001, Durban 4000 (South Africa)
2015-08-28
We present an implementation of the Deutsch Algorithm using linear optical elements and laser light. We encoded two quantum bits in form of superpositions of electromagnetic fields in two degrees of freedom of the beam: its polarisation and orbital angular momentum. Our approach, based on a Sagnac interferometer, offers outstanding stability and demonstrates that optical quantum computation is possible using classical states of light. - Highlights: • We implement the Deutsh Algorithm using linear optical elements and classical light. • Our qubits are encoded in the polarisation and orbital angular momentum of the beam. • We show that it is possible to achieve quantum computation with two qubits in the classical domain of light.
Classical and quantum dynamics from classical paths to path integrals
Dittrich, Walter
2016-01-01
Graduate students who want to become familiar with advanced computational strategies in classical and quantum dynamics will find here both the fundamentals of a standard course and a detailed treatment of the time-dependent oscillator, Chern-Simons mechanics, the Maslov anomaly and the Berry phase, to name a few. Well-chosen and detailed examples illustrate the perturbation theory, canonical transformations, the action principle and demonstrate the usage of path integrals. This new edition has been revised and enlarged with chapters on quantum electrodynamics, high energy physics, Green’s functions and strong interaction.
Non-classical continuum mechanics a dictionary
Maugin, Gérard A
2017-01-01
This dictionary offers clear and reliable explanations of over 100 keywords covering the entire field of non-classical continuum mechanics and generalized mechanics, including the theory of elasticity, heat conduction, thermodynamic and electromagnetic continua, as well as applied mathematics. Every entry includes the historical background and the underlying theory, basic equations and typical applications. The reference list for each entry provides a link to the original articles and the most important in-depth theoretical works. Last but not least, every entry is followed by a cross-reference to other related subject entries in the dictionary.
Electromagnetic waves in gravitational wave spacetimes
International Nuclear Information System (INIS)
Haney, M.; Bini, D.; Ortolan, A.; Fortini, P.
2013-01-01
We have considered the propagation of electromagnetic waves in a space-time representing an exact gravitational plane wave and calculated the induced changes on the four-potential field Aμ of a plane electromagnetic wave. By choosing a suitable photon round-trip in a Michelson interferometer, we have been able to identify the physical effects of the exact gravitational wave on the electromagnetic field, i.e. phase shift, change of the polarization vector, angular deflection and delay. These results have been exploited to study the response of an interferometric gravitational wave detector beyond the linear approximation of the general theory of relativity. A much more detailed examination of this problem can be found in our paper recently published in Classical and Quantum Gravity (28 (2011) 235007).
Electromagnetic Field Theory A Collection of Problems
Mrozynski, Gerd
2013-01-01
After a brief introduction into the theory of electromagnetic fields and the definition of the field quantities the book teaches the analytical solution methods of Maxwell’s equations by means of several characteristic examples. The focus is on static and stationary electric and magnetic fields, quasi stationary fields, and electromagnetic waves. For a deeper understanding, the many depicted field patterns are very helpful. The book offers a collection of problems and solutions which enable the reader to understand and to apply Maxwell’s theory for a broad class of problems including classical static problems right up to waveguide eigenvalue problems. Content Maxwell’s Equations - Electrostatic Fields - Stationary Current Distributions – Magnetic Field of Stationary Currents – Quasi Stationary Fields: Eddy Currents - Electromagnetic Waves Target Groups Advanced Graduate Students in Electrical Engineering, Physics, and related Courses Engineers and Physicists Authors Professor Dr.-Ing. Gerd Mrozynski...
Understanding geometric algebra for electromagnetic theory
Arthur, John W
2011-01-01
"This book aims to disseminate geometric algebra as a straightforward mathematical tool set for working with and understanding classical electromagnetic theory. It's target readership is anyone who has some knowledge of electromagnetic theory, predominantly ordinary scientists and engineers who use it in the course of their work, or postgraduate students and senior undergraduates who are seeking to broaden their knowledge and increase their understanding of the subject. It is assumed that the reader is not a mathematical specialist and is neither familiar with geometric algebra or its application to electromagnetic theory. The modern approach, geometric algebra, is the mathematical tool set we should all have started out with and once the reader has a grasp of the subject, he or she cannot fail to realize that traditional vector analysis is really awkward and even misleading by comparison"--Provided by publisher.
Investigation of classical radiation reaction with aligned crystals
Energy Technology Data Exchange (ETDEWEB)
Di Piazza, A., E-mail: dipiazza@mpi-hd.mpg.de [Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, D-69117 (Germany); Wistisen, Tobias N.; Uggerhøj, Ulrik I. [Department of Physics and Astronomy, Aarhus University, 8000 Aarhus (Denmark)
2017-02-10
Classical radiation reaction is the effect of the electromagnetic field emitted by an accelerated electric charge on the motion of the charge itself. The self-consistent underlying classical equation of motion including radiation–reaction effects, the Landau–Lifshitz equation, has never been tested experimentally, in spite of the first theoretical treatments of radiation reaction having been developed more than a century ago. Here we show that classical radiation reaction effects, in particular those due to the near electromagnetic field, as predicted by the Landau–Lifshitz equation, can be measured in principle using presently available facilities, in the energy emission spectrum of 30-GeV electrons crossing a 0.55-mm thick diamond crystal in the axial channeling regime. Our theoretical results indicate the feasibility of the suggested setup, e.g., at the CERN Secondary Beam Areas (SBA) beamlines.
Charged particles in external electromagnetic fields
International Nuclear Information System (INIS)
Giovannini, N.P.D.
1976-01-01
The present study contains a general theoretical group analysis of the problem of a charged massive particle moving in an (arbitrary) classical external electromagnetic field. This analysis is essentially based on the space-time symmetry properties of e.m. fields and e.m. field equations, as well as the fact that the considered equations of motion depend on the field via a potential
Synthetic electromagnetic knot in a three-dimensional skyrmion
Lee, Wonjae; Gheorghe, Andrei H.; Tiurev, Konstantin; Ollikainen, Tuomas; Möttönen, Mikko; Hall, David S.
2018-01-01
Classical electromagnetism and quantum mechanics are both central to the modern understanding of the physical world and its ongoing technological development. Quantum simulations of electromagnetic forces have the potential to provide information about materials and systems that do not have conveniently solvable theoretical descriptions, such as those related to quantum Hall physics, or that have not been physically observed, such as magnetic monopoles. However, quantum simulations that simul...
Rydberg atoms ionization by microwave field and electromagnetic pulses
International Nuclear Information System (INIS)
Kaulakys, B.; Vilutis, G.
1995-01-01
A simple theory of the Rydberg atoms ionization by electromagnetic pulses and microwave field is presented. The analysis is based on the scale transformation which reduces the number of parameters and reveals the functional dependencies of the processes. It is shown that the observed ionization of Rydberg atoms by subpicosecond electromagnetic pulses scale classically. The threshold electric field required to ionise a Rydberg state may be simply evaluated in the photonic basis approach for the quantum dynamics or from the multiphoton ionization theory
Explicit symmetry breaking in electrodynamic systems and electromagnetic radiation
Sinha, Dhiraj
2016-01-01
This book is an introduction to the concept of symmetries in electromagnetism and explicit symmetry breaking. It begins with a brief background on the origin of the concept of symmetry and its meaning in fields such as architecture, mathematics and physics. Despite the extensive developments of symmetry in these fields, it has yet to be applied to the context of classical electromagnetism and related engineering applications. This book unravels the beauty and excitement of this area to scientists and engineers.
Supersymmetric classical mechanics
International Nuclear Information System (INIS)
Biswas, S.N.; Soni, S.K.
1986-01-01
The purpose of the paper is to construct a supersymmetric Lagrangian within the framework of classical mechanics which would be regarded as a candidate for passage to supersymmetric quantum mechanics. 5 refs. (author)
Mathematical physics classical mechanics
Knauf, Andreas
2018-01-01
As a limit theory of quantum mechanics, classical dynamics comprises a large variety of phenomena, from computable (integrable) to chaotic (mixing) behavior. This book presents the KAM (Kolmogorov-Arnold-Moser) theory and asymptotic completeness in classical scattering. Including a wealth of fascinating examples in physics, it offers not only an excellent selection of basic topics, but also an introduction to a number of current areas of research in the field of classical mechanics. Thanks to the didactic structure and concise appendices, the presentation is self-contained and requires only knowledge of the basic courses in mathematics. The book addresses the needs of graduate and senior undergraduate students in mathematics and physics, and of researchers interested in approaching classical mechanics from a modern point of view.
Electromagnetic wave analogue of an electronic diode
International Nuclear Information System (INIS)
Shadrivov, Ilya V; Powell, David A; Kivshar, Yuri S; Fedotov, Vassili A; Zheludev, Nikolay I
2011-01-01
An electronic diode is a nonlinear semiconductor circuit component that allows conduction of electrical current in one direction only. A component with similar functionality for electromagnetic waves, an electromagnetic isolator, is based on the Faraday effect of rotation of the polarization state and is also a key component in optical and microwave systems. Here we demonstrate a chiral electromagnetic diode, which is a direct analogue of an electronic diode: its functionality is underpinned by an extraordinarily strong nonlinear wave propagation effect in the same way as the electronic diode function is provided by the nonlinear current characteristic of a semiconductor junction. The effect exploited in this new electromagnetic diode is an intensity-dependent polarization change in an artificial chiral metamolecule. This microwave effect exceeds a similar optical effect previously observed in natural crystals by more than 12 orders of magnitude and a direction-dependent transmission that differs by a factor of 65.
CONSEQUENCES OF SYMMETRY GROUPS FOR ELECTROMAGNETIC PROPERTIES
Energy Technology Data Exchange (ETDEWEB)
MacFarlane, A. J.; Sudarshan, E. C.G.
1963-06-15
The electromagnetic properties of SU/sub 3/ supermultiplets are obtained formally by a unitary transformation of a theory whose SU/sub 3/ invariant strong interactions are perturbed by merely charge-independent interactions. Several new results are presented, but the emphasis is on the simplicity and power of the method. Electromagnetic properties of the first and second kinds are distinguished, the former being independent of the precise manner in which the particular electromagnetic property depends on the electric charge current density. It is shown that all except two relations between the magnetic moments of the baryon octet hold equally well for other electromagnetic properties like self energies and Compton scattering amplitudes. (auth)
A Synthetic Approach to the Transfer Matrix Method in Classical and Quantum Physics
Pujol, O.; Perez, J. P.
2007-01-01
The aim of this paper is to propose a synthetic approach to the transfer matrix method in classical and quantum physics. This method is an efficient tool to deal with complicated physical systems of practical importance in geometrical light or charged particle optics, classical electronics, mechanics, electromagnetics and quantum physics. Teaching…
The electromagnetic interferent antennae for gravitational waves detection
International Nuclear Information System (INIS)
Kulak, A.
1984-01-01
An electromagnetic wave propagating in the toroidal waveguide is considered as an electromagnetic gravitational antenna. An interferometric method is applied to measure the disturbances of phase of the electromagnetic field caused by the incident gravitational wave. The calculations presented take into account the dispersive and dissipative phenomena occurring during the interaction between electromagnetic and gravitational fields. The active cross-section of the antenna interacting with coherent and pulsed gravitational radiation is estimated. Experimental possibilities presently available are discussed. Limiting fluxes in the astrophysical range of frequencies measured by the interferometric electromagnetic antenna are a factor of ten or so smaller than in the case of a classic mechanical antenna. Moreover the antenna could be used for carrying out a gravitational Hertz experiment. (author)
The electromagnetic potentials without the gauge transformations
Energy Technology Data Exchange (ETDEWEB)
Espinoza, Augusto; Chubykalo, Andrey; Rodriguez, Alejandro Gutierrez; Hernandez, Maria de los Angeles [Universidad Autonoma de Zacatecas (Mexico). Unidad Academica de Fisica
2011-07-01
In this note we show that the use of the Helmholtz theorem lead to derivation of uniquely determined electromagnetic potentials without making use of the gauge transformation. These potentials correspond to the potentials obtained by imposing so-called Coulomb condition (gauge) in the traditional approach. We show that the electromagnetic field comprises two components, one of which is characterized by its instantaneous action at a distance, whereas another one propagates in the retarded form with the velocity of light. One of the theoretical consequences of this new definition is that the electromagnetic potentials are real physical quantities as well as the electric and magnetic fields. We show that the reality of the electromagnetic potentials in quantum-mechanics is also a property of these potentials in the classical electrodynamics. Equations for potentials obtained in our approach are already separated with respect to vector and scalar potentials, so there is no necessity in using the gauge transformations and, accordingly, in making use of either Lorentz or Coulomb condition. The vector potential and scalar potential introduced thus are uniquely defined. The scalar potential is a generator of the so called instantaneous action at a distance, whereas the solenoidal vector potential can propagate with the velocity of light and it is responsible for the retarded action of the electromagnetic field. (author)
Quantum processes in a strong electromagnetic field producing pairs. 3
International Nuclear Information System (INIS)
Gitman, D.M.; Gavrilov, S.P.
1977-01-01
The Furry picture in quantum electrodynamics with an external field producing real pairs has been generalized. For the required generalization to be achieved all operators of a spinor field are expressed through functions of production and annihilation operators and formulated are the rules for reduction to a generalized normal form, i.e., to such a form in which all the production operators in each term are on the left from all the annihilation operators. The diagram technique for matrix elements of random processes has been considered
Electromagnetic wave matching device
International Nuclear Information System (INIS)
Hirata, Yosuke; Mitsunaka, Yoshika; Hayashi, Ken-ichi; Ito, Yasuyuki.
1997-01-01
The present invention provides a matching device capable of increasing an efficiency of combining beams of electromagnetic waves outputted from an output window of a gyrotron which is expected for plasma heating of a thermonuclear reactor and an electromagnetic wave transmission system as high as possible. Namely, an electromagnetic wave matching device reflects beams of electromagnetic waves incident from an inlet by a plurality of phase correction mirrors and combines them to an external transmission system through an exit. In this case, the phase correction mirrors change the phase of the beams of electromagnetic waves incident to the phase correction mirrors by a predetermined amount corresponding to the position of the reflection mirrors. Then, the beams of electromagnetic waves outputted, for example, from a gyrotron can properly be shaped as desired for the intensity and the phase. As a result, combination efficiency with the transmission system can be increased. (I.S.)
Electromagnetic Gowdy universe
International Nuclear Information System (INIS)
Charach, C.
1979-01-01
Following Gowdy and Berger we construct an inhomogeneous closed electromagnetic universe with three-torus topology. This model is obtained as a result of the homogeneity breaking in the electromagnetic Bianchi type-I universe and contains interacting gravitational and electromagnetic waves. This cosmological solution provides an exactly solvable model for the study of the nonlinear fully relativistic regime of coupled electromagnetic and gravitational fields in the early universe. The asymptotic behavior is considered (i) in the vicinity of the initial singularity and (ii) in the high-frequency limit. It is shown that the effects of coupling between electromagnetic and gravitational waves cause an evolution which is significantly different from that of the vacuum model. The influence of the primordial homogeneous electromagnetic field on the dynamics of the model is also discussed
Electromagnetic ultrasonic guided waves
Huang, Songling; Li, Weibin; Wang, Qing
2016-01-01
This book introduces the fundamental theory of electromagnetic ultrasonic guided waves, together with its applications. It includes the dispersion characteristics and matching theory of guided waves; the mechanism of production and theoretical model of electromagnetic ultrasonic guided waves; the effect mechanism between guided waves and defects; the simulation method for the entire process of electromagnetic ultrasonic guided wave propagation; electromagnetic ultrasonic thickness measurement; pipeline axial guided wave defect detection; and electromagnetic ultrasonic guided wave detection of gas pipeline cracks. This theory and findings on applications draw on the author’s intensive research over the past eight years. The book can be used for nondestructive testing technology and as an engineering reference work. The specific implementation of the electromagnetic ultrasonic guided wave system presented here will also be of value for other nondestructive test developers.
Basic Electromagnetism and Materials
Moliton, André
2007-01-01
Basic Electromagnetism and Materials is the product of many years of teaching basic and applied electromagnetism. This textbook can be used to teach electromagnetism to a wide range of undergraduate science majors in physics, electrical engineering or materials science. However, by making lesser demands on mathematical knowledge than competing texts, and by emphasizing electromagnetic properties of materials and their applications, this textbook is uniquely suited to students of materials science. Many competing texts focus on the study of propagation waves either in the microwave or optical domain, whereas Basic Electromagnetism and Materials covers the entire electromagnetic domain and the physical response of materials to these waves. Professor André Moliton is Director of the Unité de Microélectronique, Optoélectronique et Polymères (Université de Limoges, France), which brings together three groups studying the optoelectronics of molecular and polymer layers, micro-optoelectronic systems for teleco...
Fundamental Elements and Interactions of Nature: A Classical Unification Theory
Directory of Open Access Journals (Sweden)
Tianxi Zhang
2010-04-01
Full Text Available A classical unification theory that completely unifies all the fundamental interactions of nature is developed. First, the nature is suggested to be composed of the following four fundamental elements: mass, radiation, electric charge, and color charge. All known types of matter or particles are a combination of one or more of the four fundamental elements. Photons are radiation; neutrons have only mass; protons have both mass and electric charge; and quarks contain mass, electric charge, and color charge. The nature fundamental interactions are interactions among these nature fundamental elements. Mass and radiation are two forms of real energy. Electric and color charges are considered as two forms of imaginary energy. All the fundamental interactions of nature are therefore unified as a single interaction between complex energies. The interaction between real energies is the gravitational force, which has three types: mass-mass, mass-radiation, and radiation-radiation interactions. Calculating the work done by the mass-radiation interaction on a photon derives the Einsteinian gravitational redshift. Calculating the work done on a photon by the radiation-radiation interaction derives a radiation redshift, which is much smaller than the gravitational redshift. The interaction between imaginary energies is the electromagnetic (between electric charges, weak (between electric and color charges, and strong (between color charges interactions. In addition, we have four imaginary forces between real and imaginary energies, which are mass-electric charge, radiation-electric charge, mass-color charge, and radiation-color charge interactions. Among the four fundamental elements, there are ten (six real and four imaginary fundamental interactions. This classical unification theory deepens our understanding of the nature fundamental elements and interactions, develops a new concept of imaginary energy for electric and color charges, and provides a
Fundamental Elements and Interactions of Nature: A Classical Unification Theory
Directory of Open Access Journals (Sweden)
Zhang T. X.
2010-04-01
Full Text Available A classical unification theory that completely unifies all the fundamental interactions of nature is developed. First, the nature is suggested to be composed of the following four fundamental elements: mass, radiation, electric charge, and color charge. All known types of matter or particles are a combination of one or more of the four fundamental elements. Photons are radiation; neutrons have only mass; protons have both mass and electric charge; and quarks contain mass, electric charge, and color charge. The nature fundamental interactions are interactions among these nature fundamental elements. Mass and radiation are two forms of real energy. Electric and color charges are con- sidered as two forms of imaginary energy. All the fundamental interactions of nature are therefore unified as a single interaction between complex energies. The interac- tion between real energies is the gravitational force, which has three types: mass-mass, mass-radiation, and radiation-radiation interactions. Calculating the work done by the mass-radiation interaction on a photon derives the Einsteinian gravitational redshift. Calculating the work done on a photon by the radiation-radiation interaction derives a radiation redshift, which is much smaller than the gravitational redshift. The interaction between imaginary energies is the electromagnetic (between electric charges, weak (between electric and color charges, and strong (between color charges interactions. In addition, we have four imaginary forces between real and imaginary energies, which are mass-electric charge, radiation-electric charge, mass-color charge, and radiation- color charge interactions. Among the four fundamental elements, there are ten (six real and four imaginary fundamental interactions. This classical unification theory deep- ens our understanding of the nature fundamental elements and interactions, develops a new concept of imaginary energy for electric and color charges, and provides a
Review on Computational Electromagnetics
Directory of Open Access Journals (Sweden)
P. Sumithra
2017-03-01
Full Text Available Computational electromagnetics (CEM is applied to model the interaction of electromagnetic fields with the objects like antenna, waveguides, aircraft and their environment using Maxwell equations. In this paper the strength and weakness of various computational electromagnetic techniques are discussed. Performance of various techniques in terms accuracy, memory and computational time for application specific tasks such as modeling RCS (Radar cross section, space applications, thin wires, antenna arrays are presented in this paper.
Static electromagnetic frequency changers
Rozhanskii, L L
1963-01-01
Static Electromagnetic Frequency Changers is about the theory, design, construction, and applications of static electromagnetic frequency changers, devices that used for multiplication or division of alternating current frequency. It is originally published in the Russian language. This book is organized into five chapters. The first three chapters introduce the readers to the principles of operation, the construction, and the potential applications of static electromagnetic frequency changers and to the principles of their design. The two concluding chapters use some hitherto unpublished work
Model for Electromagnetic Information Leakage
Mao Jian; Li Yongmei; Zhang Jiemin; Liu Jinming
2013-01-01
Electromagnetic leakage will happen in working information equipments; it could lead to information leakage. In order to discover the nature of information in electromagnetic leakage, this paper combined electromagnetic theory with information theory as an innovative research method. It outlines a systematic model of electromagnetic information leakage, which theoretically describes the process of information leakage, intercept and reproduction based on electromagnetic radiation, and ana...
Electromagnetic Interface Testing Facility
Federal Laboratory Consortium — The Electromagnetic Interface Testing facilitysupports such testing asEmissions, Field Strength, Mode Stirring, EMP Pulser, 4 Probe Monitoring/Leveling System, and...
Classical geometry from the quantum Liouville theory
Hadasz, Leszek; Jaskólski, Zbigniew; Piaţek, Marcin
2005-09-01
Zamolodchikov's recursion relations are used to analyze the existence and approximations to the classical conformal block in the case of four parabolic weights. Strong numerical evidence is found that the saddle point momenta arising in the classical limit of the DOZZ quantum Liouville theory are simply related to the geodesic length functions of the hyperbolic geometry on the 4-punctured Riemann sphere. Such relation provides new powerful methods for both numerical and analytical calculations of these functions. The consistency conditions for the factorization of the 4-point classical Liouville action in different channels are numerically verified. The factorization yields efficient numerical methods to calculate the 4-point classical action and, by the Polyakov conjecture, the accessory parameters of the Fuchsian uniformization of the 4-punctured sphere.
Classical geometry from the quantum Liouville theory
Energy Technology Data Exchange (ETDEWEB)
Hadasz, Leszek [M. Smoluchowski Institute of Physics, Jagellonian University, Reymonta 4, 30-059 Cracow (Poland)]. E-mail: hadasz@th.if.uj.edu.pl; Jaskolski, Zbigniew [Institute of Theoretical Physics, University of WrocIaw, pl. M. Borna, 950-204 WrocIaw (Poland)]. E-mail: jask@ift.uni.wroc.pl; Piatek, Marcin [Institute of Theoretical Physics, University of WrocIaw, pl. M. Borna, 950-204 WrocIaw (Poland)]. E-mail: piatek@ift.uni.wroc.pl
2005-09-26
Zamolodchikov's recursion relations are used to analyze the existence and approximations to the classical conformal block in the case of four parabolic weights. Strong numerical evidence is found that the saddle point momenta arising in the classical limit of the DOZZ quantum Liouville theory are simply related to the geodesic length functions of the hyperbolic geometry on the 4-punctured Riemann sphere. Such relation provides new powerful methods for both numerical and analytical calculations of these functions. The consistency conditions for the factorization of the 4-point classical Liouville action in different channels are numerically verified. The factorization yields efficient numerical methods to calculate the 4-point classical action and, by the Polyakov conjecture, the accessory parameters of the Fuchsian uniformization of the 4-punctured sphere.
Classical geometry from the quantum Liouville theory
International Nuclear Information System (INIS)
Hadasz, Leszek; Jaskolski, Zbigniew; Piatek, Marcin
2005-01-01
Zamolodchikov's recursion relations are used to analyze the existence and approximations to the classical conformal block in the case of four parabolic weights. Strong numerical evidence is found that the saddle point momenta arising in the classical limit of the DOZZ quantum Liouville theory are simply related to the geodesic length functions of the hyperbolic geometry on the 4-punctured Riemann sphere. Such relation provides new powerful methods for both numerical and analytical calculations of these functions. The consistency conditions for the factorization of the 4-point classical Liouville action in different channels are numerically verified. The factorization yields efficient numerical methods to calculate the 4-point classical action and, by the Polyakov conjecture, the accessory parameters of the Fuchsian uniformization of the 4-punctured sphere
DEFF Research Database (Denmark)
Brincker, Benedikte
The last book Anthony D. Smith wrote before he died, and which will be published in Spring 2017, has the title Nation and Classical Music. Smith had for a long time been intrigued by the intimate relationship between the nation and classical music. At the most manifest level it involves...... them into their compositions thus challenging the romantic musical style searching for an authentic national musical expression. Against the backdrop of the extensive research carried out by Anthony Smith into the relationship between the nation and classical music, the present paper seeks to add...... cultural centers. In doing this, the paper seeks to unfold how composers channeled musical inspiration embedded in cultural environments that cut across national boundaries into national musical traditions thus catering to specific national audiences. The paper is written as a tribute to a great mentor...
Twisted classical Poincare algebras
International Nuclear Information System (INIS)
Lukierski, J.; Ruegg, H.; Tolstoy, V.N.; Nowicki, A.
1993-11-01
We consider the twisting of Hopf structure for classical enveloping algebra U(g), where g is the inhomogeneous rotations algebra, with explicite formulae given for D=4 Poincare algebra (g=P 4 ). The comultiplications of twisted U F (P 4 ) are obtained by conjugating primitive classical coproducts by F element of U(c)xU(c), where c denotes any Abelian subalgebra of P 4 , and the universal R-matrices for U F (P 4 ) are triangular. As an example we show that the quantum deformation of Poincare algebra recently proposed by Chaichian and Demiczev is a twisted classical Poincare algebra. The interpretation of twisted Poincare algebra as describing relativistic symmetries with clustered 2-particle states is proposed. (orig.)
Classical mechanics with Maxima
Timberlake, Todd Keene
2016-01-01
This book guides undergraduate students in the use of Maxima—a computer algebra system—in solving problems in classical mechanics. It functions well as a supplement to a typical classical mechanics textbook. When it comes to problems that are too difficult to solve by hand, computer algebra systems that can perform symbolic mathematical manipulations are a valuable tool. Maxima is particularly attractive in that it is open-source, multiple-platform software that students can download and install free of charge. Lessons learned and capabilities developed using Maxima are easily transferred to other, proprietary software.
Iselin, F Christoph
1996-01-01
Exchange of data and algorithms among accelerator physics programs is difficult because of unnecessary differences in input formats and internal data structures. To alleviate these problems a C++ class library called CLASSIC (Clas Library for Accelerator System Simulation and Control) is being developed with the goal to provide standard building blocks for computer programs used in accelerator lattice structures in computer memory using a standard input language, a graphical user interface, or a programmed algorithm. It also provides simulation algorithms. These can easily be replaced by modules which communicate with the control system of the accelerator. Exchange of both data and algorithm between different programs using the CLASSIC library should present no difficulty.
Learning Classical Music Club
2010-01-01
There is a new CERN Club called “Learning Classical Music at CERN”. We are aiming to give classical music lessons for different instruments (see link) for students from 5 to 100 years old. We are now ready to start our activities in the CERN barracks. We are now in the enrollment phase and hope to start lessons very soon ! Club info can be found in the list of CERN Club: http://user.web.cern.ch/user/Communication/SocialLifeActivities/Clubs/Clubs.html Salvatore Buontempo Club President
International Nuclear Information System (INIS)
Starrfield, S.G.
1988-01-01
The classical nova outburst occurs on the white dwarf component in a close binary system. Nova systems are members of the general class of cataclysmic variables and other members of the class are the Dwarf Novae, AM Her variables, Intermediate Polars, Recurrent Novae, and some of the Symbiotic variables. Although multiwavelength observations have already provided important information about all of these systems, in this review I will concentrate on the outbursts of the classical and recurrent novae and refer to other members of the class only when necessary. 140 refs., 1 tab
Elementary classical hydrodynamics
Chirgwin, B H; Langford, W J; Maxwell, E A; Plumpton, C
1967-01-01
Elementary Classical Hydrodynamics deals with the fundamental principles of elementary classical hydrodynamics, with emphasis on the mechanics of inviscid fluids. Topics covered by this book include direct use of the equations of hydrodynamics, potential flows, two-dimensional fluid motion, waves in liquids, and compressible flows. Some general theorems such as Bernoulli's equation are also considered. This book is comprised of six chapters and begins by introducing the reader to the fundamental principles of fluid hydrodynamics, with emphasis on ways of studying the motion of a fluid. Basic c
Classic Problems of Probability
Gorroochurn, Prakash
2012-01-01
"A great book, one that I will certainly add to my personal library."—Paul J. Nahin, Professor Emeritus of Electrical Engineering, University of New Hampshire Classic Problems of Probability presents a lively account of the most intriguing aspects of statistics. The book features a large collection of more than thirty classic probability problems which have been carefully selected for their interesting history, the way they have shaped the field, and their counterintuitive nature. From Cardano's 1564 Games of Chance to Jacob Bernoulli's 1713 Golden Theorem to Parrondo's 1996 Perplexin
Electromagnetism of Bacterial Growth
Ainiwaer, Ailiyasi
2011-10-01
There has been increasing concern from the public about personal health due to the significant rise in the daily use of electrical devices such as cell phones, radios, computers, GPS, video games and television. All of these devices create electromagnetic (EM) fields, which are simply magnetic and electric fields surrounding the appliances that simultaneously affect the human bio-system. Although these can affect the human system, obstacles can easily shield or weaken the electrical fields; however, magnetic fields cannot be weakened and can pass through walls, human bodies and most other objects. The present study was conducted to examine the possible effects of bacteria when exposed to magnetic fields. The results indicate that a strong causal relationship is not clear, since different magnetic fields affect the bacteria differently, with some causing an increase in bacterial cells, and others causing a decrease in the same cells. This phenomenon has yet to be explained, but the current study attempts to offer a mathematical explanation for this occurrence. The researchers added cultures to the magnetic fields to examine any effects to ion transportation. Researchers discovered ions such as potassium and sodium are affected by the magnetic field. A formula is presented in the analysis section to explain this effect.
George, Judith W.
2009-01-01
The article identifies some key findings in pedagogical research over recent decades, placing them within a framework of logical curriculum development and current practice in quality assurance and enhancement. Throughout, the ideas and comments are related to the practice of teaching classics in university. (Contains 1 figure and 3 notes.)
Classical solutions in supergravity
International Nuclear Information System (INIS)
Baaklini, N.S.; Ferrara, S.; Nieuwenhuizen Van, P.
1977-06-01
Classical solutions of supergravity are obtained by making finite global supersymmetry rotation on known solutions of the field equations of the bosonic sector. The Schwarzschild and the Reissner-Nordstoem solutions of general relativity are extended to various supergravity systems and the modification to the perihelion precession of planets is discussed
Huddleston, Gregory H.
1993-01-01
Describes one teacher's methods for introducing to secondary English students the concepts of Classicism and Romanticism in relation to pictures of gardens, architecture, music, and literary works. Outlines how the unit leads to a writing assignment based on collected responses over time. (HB)
Classical Mythology. Fourth Edition.
Morford, Mark P. O.; Lenardon, Robert J.
Designed for students with little or no background in classical literature, this book introduces the Greek and Roman myths of creation, myths of the gods, Greek sagas and local legends, and presents contemporary theories about the myths. Drawing on Homer, Hesiod, Pindar, Vergil, and others, the book provides many translations and paraphrases of…
Tighe, Mary Ann; Avinger, Charles
1994-01-01
Describes young adult novels that may prove to be classics of the genre. Discusses "The "Chocolate War" by Robert Cormier, "The Outsiders" by S. E. Hinton, "The Witch of Blackbird Pond" by Elizabeth George Speare, and "On Fortune's Wheel" by Cynthia Voight. (HB)
Why Study Classical Languages?
Lieberman, Samuel
This speech emphasizes the significance of living literatures and living cultures which owe a direct debt to the Romans and the Greeks from whom they can trace their origins. After commenting on typical rejoinders to the question "Why study classical languages?" and poking fun at those who advance jaded, esoteric responses, the author dispels the…
Bright branes for strongly coupled plasmas
International Nuclear Information System (INIS)
Mateos, David; Patino, Leonardo
2007-01-01
We use holographic techniques to study photon production in a class of finite temperature, strongly coupled, large-N c SU(N c ) quark-gluon plasmas with N f c quark flavours. Our results are valid to leading order in the electromagnetic coupling constant but non-perturbatively in the SU(N c ) interactions. The spectral function of electromagnetic currents and other related observables exhibit an interesting structure as a function of the photon frequency and the quark mass. We discuss possible implications for heavy ion collision experiments
An Electromagnetic Beam Converter
DEFF Research Database (Denmark)
2009-01-01
The present invention relates to an electromagnetic beam converter and a method for conversion of an input beam of electromagnetic radiation having a bell shaped intensity profile a(x,y) into an output beam having a prescribed target intensity profile l(x',y') based on a further development...
High frequency electromagnetic dosimetry
Sánchez-Hernández, David A
2009-01-01
Along with the growth of RF and microwave technology applications, there is a mounting concern about the possible adverse effects over human health from electromagnetic radiation. Addressing this issue and putting it into perspective, this groundbreaking resource provides critical details on the latest advances in high frequency electromagnetic dosimetry.
Electromagnetically Operated Counter
Goldberg, H D; Goldberg, M I
1951-12-18
An electromagnetically operated counter wherein signals to be counted are applied to cause stepwise rotation of a rotatable element which is connected to a suitable register. The mechanism involved consists of a rotatable armature having three spaced cores of magnetic material and a pair of diametrically opposed electromagnets with a suitable pulsing circuit to actuate the magnets.
Electromagnetic cyclotron harmonic waves
International Nuclear Information System (INIS)
Ohnuma, T.; Watanabe, T.; Hamamatsu, K.
1981-09-01
Electromagnetic electron cyclotron harmonic waves just below the electron cyclotron harmonics are investigated numerically and experimentally. Backward waves which are observed to propagate nearly perpendicular to the magnetic field just below the electron cyclotron frequency in a high density magnetoplasma are confirmed to be in accord with the theoretical electromagnetic cyclotron waves. (author)
Electromagnetic signals of quark gluon plasma
Indian Academy of Sciences (India)
Successive equilibration of quark degrees of freedom and its effects on electromagnetic signals of quark gluon plasma are discussed. The effects of the variation of vector meson masses and decay widths on photon production from hot strongly interacting matter formed after Pb + Pb and S + Au collisions at CERN SPS ...
Babin, Anatoli
2016-01-01
In this monograph, the authors present their recently developed theory of electromagnetic interactions. This neoclassical approach extends the classical electromagnetic theory down to atomic scales and allows the explanation of various non-classical phenomena in the same framework. While the classical Maxwell–Lorentz electromagnetism theory succeeds in describing the physical reality at macroscopic scales, it struggles at atomic scales. Here, quantum mechanics traditionally takes over to describe non-classical phenomena such as the hydrogen spectrum and de Broglie waves. By means of modifying the classical theory, the approach presented here is able to consistently explain quantum-mechanical effects, and while similar to quantum mechanics in some respects, this neoclassical theory also differs markedly from it. In particular, the newly developed framework omits probabilistic interpretations of the wave function and features a new fundamental spatial scale which, at the size of the free electron, is much lar...
Scalar and electromagnetic fields in the Kazner metric. Interaction as a mechanism of isotronization
International Nuclear Information System (INIS)
Krechet, V.G.; Shikin, G.N.
1981-01-01
Within the framework of the Willer-de Vitt superspatial quantization the quantum anisotropic cosmological model with interacting, scalar and electromagnetic fields is considered. It is shown that as a result of direct interaction of the scalar and electromagnetic fields isotropization of the model occurs as in the classical case. While comparing the classical and quantum approaches the conclusion is made that in the quantum approach there are states without initial singularity, that fails in the classical approach; both in the quantum and classical approaches there is isotropization of evolution of the interacting field system (in the quantum approach in α, and β), and in both approaches this process is a consequence of direct interaction of the scalar and electromagnetic fields; in the quantum approach, unlike the classical one, there exists isotropization of the considered model at an infinite growth of the scalar field [ru
International Nuclear Information System (INIS)
Li Zhong-Hua; Li Yuan; Dou Ya-Fang; Zhang Jun-Xiang
2012-01-01
The quantum noise of squeezed probe light passing through an atomic system with different electromagnetically induced transparency and Autler—Townes splitting effects is investigated theoretically. It is found that the optimal squeezing preservation of the outgoing probe beam occurs in the strong-coupling-field regime rather than in the weak-coupling-field regime. In the weak-coupling-field regime, which was recently recognized as the electromagnetically induced transparency regime (Abi-Salloum T Y 2010 Phys. Rev. A 81 053836), the output amplitude noise is affected mainly by the atomic noise originating from the random decay process of atoms. While in the strong-coupling-field regime, defined as the Autler—Townes splitting regime, the output amplitude noise is affected mainly by the phase-to-amplitude conversion noise. This is useful in improving the quality of the experiment for efficient quantum memory, and hence has an application in quantum information processing. (electromagnetism, optics, acoustics, heat transfer, classical mechanics, and fluid dynamics)
1000 Solved Problems in Classical Physics An Exercise Book
Kamal, Ahmad A
2011-01-01
This book basically caters to the needs of undergraduate and graduate physics students in classical physics, especially Classical Mechanics and Electricity and Electromagnetism. Lecturers/Tutors may use it as a resource book. The contents of the book are based on the syllabi currently used in the undergraduate courses in the USA, U.K., and other countries. The book consists of 15 chapters, each one beginning with a brief but adequate summary and necessary formulas and Line diagrams followed by a variety of typical problems useful for assignments and exams. Detailed solutions are provided at the end of each chapter.
Scattering of classical and quantum particles by impulsive fields
Balasin, Herbert; Aichelburg, Peter C.
2018-05-01
We investigate the scattering of classical and quantum particles in impulsive backgrounds fields. These fields model short outbursts of radiation propagating with the speed of light. The singular nature of the problem will be accounted for by the use of Colombeau’s generalized function which however give rise to ambiguities. It is the aim of the paper to show that these ambiguities can be overcome by implementing additional physical conditions, which in the non-singular case would be satisfied automatically. As example we discuss the scattering of classical, Klein–Gordon and Dirac particles in impulsive electromagnetic fields.
Classical and quantum electrodynamics and the B(3) field
Evans, Myron W
2001-01-01
It is well known that classical electrodynamics is riddled with internal inconsistencies springing from the fact that it is a linear, Abelian theory in which the potentials are unphysical. This volume offers a self-consistent hypothesis which removes some of these problems, as well as builds a framework on which linear and nonlinear optics are treated as a non-Abelian gauge field theory based on the emergence of the fundamental magnetizing field of radiation, the B(3) field. Contents: Interaction of Electromagnetic Radiation with One Fermion; The Field Equations of Classical O (3) b Electrodyn
Sparse symmetric preconditioners for dense linear systems in electromagnetism
Carpentieri, Bruno; Duff, Iain S.; Giraud, Luc; Monga Made, M. Magolu
2004-01-01
We consider symmetric preconditioning strategies for the iterative solution of dense complex symmetric non-Hermitian systems arising in computational electromagnetics. In particular, we report on the numerical behaviour of the classical incomplete Cholesky factorization as well as some of its recent
On quantization of the electromagnetic field in radiation gauge
International Nuclear Information System (INIS)
Burzynski, A.
1982-01-01
This paper contains a detailed description of quantization of the electromagnetic field (in radiation gauge) and quantization of some basic physical variables connected with radiation field as energy, momentum and spin. The dynamics of the free quantum radiation field and the field interacting with external classical sources is described. The canonical formalism is not used explicity. (author)
Multipole interactions of charged particles with the electromagnetic field
International Nuclear Information System (INIS)
Burzynski, A.
1982-01-01
The full multipole expansion for the lagrangian and hamiltonian of a system of point charges interacting with the electromagnetic field is studied in detail. Both classical and quantum theory are described for external and dynamical fields separately. One improvement with respect to the known Fiutak's paper is made. (author)
Stirring Strongly Coupled Plasma
Fadafan, Kazem Bitaghsir; Rajagopal, Krishna; Wiedemann, Urs Achim
2009-01-01
We determine the energy it takes to move a test quark along a circle of radius L with angular frequency w through the strongly coupled plasma of N=4 supersymmetric Yang-Mills (SYM) theory. We find that for most values of L and w the energy deposited by stirring the plasma in this way is governed either by the drag force acting on a test quark moving through the plasma in a straight line with speed v=Lw or by the energy radiated by a quark in circular motion in the absence of any plasma, whichever is larger. There is a continuous crossover from the drag-dominated regime to the radiation-dominated regime. In the crossover regime we find evidence for significant destructive interference between energy loss due to drag and that due to radiation as if in vacuum. The rotating quark thus serves as a model system in which the relative strength of, and interplay between, two different mechanisms of parton energy loss is accessible via a controlled classical gravity calculation. We close by speculating on the implicati...
Directory of Open Access Journals (Sweden)
Adriana Coutinho de Azevedo Guimarães
2008-06-01
Full Text Available This study aimed to elucidate what injuries are most likely to occur due to classical ballet practice. The research used national and international bibliography. The bibliography analysis indicated that technical and esthetical demands lead to a practice of non-anatomical movements, causing the ballet dancer to suffer from a number of associated lesions. Most of the injuries are caused by technical mistakes and wrong training. Troubles in children are usually due to trying to force external rotation at hip level and to undue use of point ballet slippers. The commonest lesions are in feet and ankles, followed by knees and hips. The rarest ones are in the upper limbs. These injuries are caused by exercise excess, by repetitions always in the same side and by wrong and early use of point slippers. The study reached the conclusion that incorrect application of classical ballet technique predisposes the dancers to characteristic injuries.
International Nuclear Information System (INIS)
Iselin, F. Christoph
1997-01-01
Exchange of data and algorithms among accelerator physics programs is difficult because of unnecessary differences in input formats and internal data structures. To alleviate these problems a C++ class library called CLASSIC (Class Library for Accelerator System Simulation and Control) is being developed with the goal to provide standard building blocks for computer programs used in accelerator design. It includes modules for building accelerator lattice structures in computer memory using a standard input language, a graphical user interface, or a programmed algorithm. It also provides simulation algorithms. These can easily be replaced by modules which communicate with the control system of the accelerator. Exchange of both data and algorithm between different programs using the CLASSIC library should present no difficulty
Classical Diophantine equations
1993-01-01
The author had initiated a revision and translation of "Classical Diophantine Equations" prior to his death. Given the rapid advances in transcendence theory and diophantine approximation over recent years, one might fear that the present work, originally published in Russian in 1982, is mostly superseded. That is not so. A certain amount of updating had been prepared by the author himself before his untimely death. Some further revision was prepared by close colleagues. The first seven chapters provide a detailed, virtually exhaustive, discussion of the theory of lower bounds for linear forms in the logarithms of algebraic numbers and its applications to obtaining upper bounds for solutions to the eponymous classical diophantine equations. The detail may seem stark--- the author fears that the reader may react much as does the tourist on first seeing the centre Pompidou; notwithstanding that, Sprind zuk maintainsa pleasant and chatty approach, full of wise and interesting remarks. His emphases well warrant, ...
Classical and statistical thermodynamics
Rizk, Hanna A
2016-01-01
This is a text book of thermodynamics for the student who seeks thorough training in science or engineering. Systematic and thorough treatment of the fundamental principles rather than presenting the large mass of facts has been stressed. The book includes some of the historical and humanistic background of thermodynamics, but without affecting the continuity of the analytical treatment. For a clearer and more profound understanding of thermodynamics this book is highly recommended. In this respect, the author believes that a sound grounding in classical thermodynamics is an essential prerequisite for the understanding of statistical thermodynamics. Such a book comprising the two wide branches of thermodynamics is in fact unprecedented. Being a written work dealing systematically with the two main branches of thermodynamics, namely classical thermodynamics and statistical thermodynamics, together with some important indexes under only one cover, this treatise is so eminently useful.
Invitation to classical analysis
Duren, Peter
2012-01-01
This book gives a rigorous treatment of selected topics in classical analysis, with many applications and examples. The exposition is at the undergraduate level, building on basic principles of advanced calculus without appeal to more sophisticated techniques of complex analysis and Lebesgue integration. Among the topics covered are Fourier series and integrals, approximation theory, Stirling's formula, the gamma function, Bernoulli numbers and polynomials, the Riemann zeta function, Tauberian theorems, elliptic integrals, ramifications of the Cantor set, and a theoretical discussion of differ
Generalized classical mechanics
International Nuclear Information System (INIS)
De Leon, M.; Rodrigues, P.R.
1985-01-01
The geometrical study of Classical Mechanics shows that the Hamiltonian (respectively, Lagrangian) formalism may be characterized by intrinsical structures canonically defined on the cotangent (respectively, tangent) bundle of a differentiable manifold. A generalized formalism for higher order Lagrangians is developed. Then the Hamiltonian form of the theory is developed. Finally, the Poisson brackets are defined and the conditions under which a mapping is a canonical transformation are studied. The Hamilton-Jacobi equation for this type of mechanics is established. (Auth.)
International Nuclear Information System (INIS)
Takahashi, Kenji.
1994-01-01
As an electromagnetic shaft seal, there are disposed outwarding electromagnetic induction devices having generating power directing to an electroconductive fluid as an object of sealing, and inwarding electromagnetic induction device added coaxially. There are disposed elongate rectangular looped first coils having a predetermined inner diameter, second coils having the same shape and shifted by a predetermined pitch relative to the first coil and third coil having the same shape and shifted by a predetermined pitch relative to the second coil respectively each at a predetermined inner diameter of clearance to the outwarding electromagnetic induction devices and the inwarding electromagnetic induction device. If the inwarding electromagnetic induction device and the outwarding electromagnetic induction device are operated, they are stopped at a point that the generating power of the former is equal with the sum of the generating power of the latter and a differential pressure. When three-phase AC is charged to the first coil, the second coil and the third coil successively, a force is generated in the advancing direction of the magnetic field in the electroconductive fluid by the similar effect to that of a linear motor, and the seal is maintained at high reliability. Moreover, the limit for the rotational angle of the shaft is not caused. (N.H.)
Classical Weyl transverse gravity
Energy Technology Data Exchange (ETDEWEB)
Oda, Ichiro [University of the Ryukyus, Department of Physics, Faculty of Science, Nishihara, Okinawa (Japan)
2017-05-15
We study various classical aspects of the Weyl transverse (WTDiff) gravity in a general space-time dimension. First of all, we clarify a classical equivalence among three kinds of gravitational theories, those are, the conformally invariant scalar tensor gravity, Einstein's general relativity and the WTDiff gravity via the gauge-fixing procedure. Secondly, we show that in the WTDiff gravity the cosmological constant is a mere integration constant as in unimodular gravity, but it does not receive any radiative corrections unlike the unimodular gravity. A key point in this proof is to construct a covariantly conserved energy-momentum tensor, which is achieved on the basis of this equivalence relation. Thirdly, we demonstrate that the Noether current for the Weyl transformation is identically vanishing, thereby implying that the Weyl symmetry existing in both the conformally invariant scalar tensor gravity and the WTDiff gravity is a ''fake'' symmetry. We find it possible to extend this proof to all matter fields, i.e. the Weyl-invariant scalar, vector and spinor fields. Fourthly, it is explicitly shown that in the WTDiff gravity the Schwarzschild black hole metric and a charged black hole one are classical solutions to the equations of motion only when they are expressed in the Cartesian coordinate system. Finally, we consider the Friedmann-Lemaitre-Robertson-Walker (FLRW) cosmology and provide some exact solutions. (orig.)
Optical tweezers and paradoxes in electromagnetism
International Nuclear Information System (INIS)
Pfeifer, Robert N C; Nieminen, Timo A; Heckenberg, Norman R; Rubinsztein-Dunlop, Halina
2011-01-01
The widespread application of optical forces and torques has contributed to renewed interest in the fundamentals of the electromagnetic force and torque, including long-standing paradoxes such as the Abraham–Minkowski controversy and the angular momentum density of a circularly polarized plane wave. We discuss the relationship between these electromagnetic paradoxes and optical tweezers. In particular, consideration of possible optical tweezers experiments to attempt to resolve these paradoxes strongly suggests that they are beyond experimental resolution, yielding identical observable results in all cases
Electromagnetically Induced Transparency In Rydberg Atomic Medium
Deng, Li; Cong, Lu; Chen, Ai-Xi
2018-03-01
Due to possessing big principal quantum number, Rydberg atom has some unique properties, for example: its radiative lifetime is long, dipole moment is large, and interaction between atoms is strong and so on. These properties make one pay attention to Rydberg atoms. In this paper we investigate the effects of Rydberg dipole-dipole interactions on electromagnetically induced transparency (EIT) schemes and group velocity in three-level systems of ladder type, which provides theoretical foundation for exploring the linear and nonlinear characteristics of light in a Rydberg electromagnetically-induced-transparency medium.
Theoretical status of weak and electromagnetic interactions
Energy Technology Data Exchange (ETDEWEB)
Pandit, L. K.
1980-07-01
An extended simple version of the Weinberg gauge model is proposed to bring together weak and electromagnetic interactions under one theory. The essential features of the standard SU/sub 2/ (operating on)U/sub 1/ gauge scheme with four leptons and four quark flavours is recalled. Charged-current and neutral current interactions are described. Non-leptonic decays of strange particles are studied. The treatment is extended to 6-leptons and 6-quark flavours. The short comings of this model are discussed. Speculations on the unification of strong, weak and electromagnetic interactions are made.
Strong Stationary Duality for Diffusion Processes
Fill, James Allen; Lyzinski, Vince
2014-01-01
We develop the theory of strong stationary duality for diffusion processes on compact intervals. We analytically derive the generator and boundary behavior of the dual process and recover a central tenet of the classical Markov chain theory in the diffusion setting by linking the separation distance in the primal diffusion to the absorption time in the dual diffusion. We also exhibit our strong stationary dual as the natural limiting process of the strong stationary dual sequence of a well ch...
Electromagnetic spatial coherence wavelets
International Nuclear Information System (INIS)
Castaneda, R.; Garcia-Sucerquia, J.
2005-10-01
The recently introduced concept of spatial coherence wavelets is generalized for describing the propagation of electromagnetic fields in the free space. For this aim, the spatial coherence wavelet tensor is introduced as an elementary amount, in terms of which the formerly known quantities for this domain can be expressed. It allows analyzing the relationship between the spatial coherence properties and the polarization state of the electromagnetic wave. This approach is completely consistent with the recently introduced unified theory of coherence and polarization for random electromagnetic beams, but it provides a further insight about the causal relationship between the polarization states at different planes along the propagation path. (author)
Nonlinear surface electromagnetic phenomena
Ponath, H-E
1991-01-01
In recent years the physics of electromagnetic surface phenomena has developed rapidly, evolving into technologies for communications and industry, such as fiber and integrated optics. The variety of phenomena based on electromagnetism at surfaces is rich and this book was written with the aim of summarizing the available knowledge in selected areas of the field. The book contains reviews written by solid state and optical physicists on the nonlinear interaction of electromagnetic waves at and with surfaces and films. Both the physical phenomena and some potential applications are
Classical algebraic chromodynamics
International Nuclear Information System (INIS)
Adler, S.L.
1978-01-01
I develop an extension of the usual equations of SU(n) chromodynamics which permits the consistent introduction of classical, noncommuting quark source charges. The extension involves adding a singlet gluon, giving a U(n) -based theory with outer product P/sup a/(u,v) = (1/2)(d/sup a/bc + if/sup a/bc)(u/sup b/v/sup c/ - v/sup b/u/sup c/) which obeys the Jacobi identity, inner product S (u,v) = (1/2)(u/sup a/v/sup a/ + v/sup a/u/sup a/), and with the n 2 gluon fields elevated to algebraic fields over the quark color charge C* algebra. I show that provided the color charge algebra satisfies the condition S (P (u,v),w) = S (u,P (v,w)) for all elements u,v,w of the algebra, all the standard derivations of Lagrangian chromodynamics continue to hold in the algebraic chromodynamics case. I analyze in detail the color charge algebra in the two-particle (qq, qq-bar, q-barq-bar) case and show that the above consistency condition is satisfied for the following unique (and, interestingly, asymmetric) choice of quark and antiquark charges: Q/sup a//sub q/ = xi/sup a/, Q/sup a//sub q/ = xi-bar/sup a/ + delta/sup a/0(n/2)/sup 3/2/1, with xi/sup a/xi/sup b/ = (1/2)(d/sup a/bc + if/sup a/bc) xi/sup c/, xi-bar/sup a/xi-bar/sup b/ = -(1/2)(d/sup a/bc - if/sup a/bc) xi-bar/sup c/. The algebraic structure of the two-particle U(n) force problem, when expressed on an appropriately diagonalized basis, leads for all n to a classical dynamics problem involving an ordinary SU(2) Yang-Mills field with uniquely specified classical source charges which are nonparallel in the color-singlet state. An explicit calculation shows that local algebraic U(n) gauge transformations lead only to a rigid global rotation of axes in the overlying classical SU(2) problem, which implies that the relative orientations of the classical source charges have physical significance
Numerical Analysis of Electromagnetic Fields in Multiscale Model
International Nuclear Information System (INIS)
Ma Ji; Fang Guang-You; Ji Yi-Cai
2015-01-01
Modeling technique for electromagnetic fields excited by antennas is an important topic in computational electromagnetics, which is concerned with the numerical solution of Maxwell's equations. In this paper, a novel hybrid technique that combines method of moments (MoM) with finite-difference time-domain (FDTD) method is presented to handle the problem. This approach employed Huygen's principle to realize the hybridization of the two classical numerical algorithms. For wideband electromagnetic data, the interpolation scheme is used in the MoM based on the dyadic Green's function. On the other hand, with the help of equivalence principle, the scattered electric and magnetic fields on the Huygen's surface calculated by MoM are taken as the sources for FDTD. Therefore, the electromagnetic fields in the environment can be obtained by employing finite-difference time-domain method. Finally, numerical results show the validity of the proposed technique by analyzing two canonical samples. (paper)
Forward modeling. Route to electromagnetic inversion
Energy Technology Data Exchange (ETDEWEB)
Groom, R; Walker, P [PetRos EiKon Incorporated, Ontario (Canada)
1996-05-01
Inversion of electromagnetic data is a topical subject in the literature, and much time has been devoted to understanding the convergence properties of various inverse methods. The relative lack of success of electromagnetic inversion techniques is partly attributable to the difficulties in the kernel forward modeling software. These difficulties come in two broad classes: (1) Completeness and robustness, and (2) convergence, execution time and model simplicity. If such problems exist in the forward modeling kernel, it was demonstrated that inversion can fail to generate reasonable results. It was suggested that classical inversion techniques, which are based on minimizing a norm of the error between data and the simulated data, will only be successful when these difficulties in forward modeling kernels are properly dealt with. 4 refs., 5 figs.
Ionization in a quantized electromagnetic field
International Nuclear Information System (INIS)
Gonoskov, I. A.; Vugalter, G. A.; Mironov, V. A.
2007-01-01
An analytical expression for a matrix element of the transition from a bound state of an electron in an atom to continuum states is obtained by solving the problem of interaction of the electron with a quantized electromagnetic field. This expression is used to derive formulas for the photoelectron spectrum and the rate of ionization of the simplest model atomic system upon absorption of an arbitrary number of photons. The expressions derived are analyzed and compared with the corresponding relationships obtained via other approaches. It is demonstrated that there are differences as compared to the case of the classical field. In particular, the photoelectron spectrum exhibits dips due to the destructive interference of the transition amplitudes in the quantized electromagnetic field
Dual field theory of strong interactions
International Nuclear Information System (INIS)
Akers, D.
1987-01-01
A dual field theory of strong interactions is derived from a Lagrangian of the Yang-Mills and Higgs fields. The existence of a magnetic monopole of mass 2397 MeV and Dirac charge g = (137/2)e is incorporated into the theory. Unification of the strong, weak, and electromagnetic forces is shown to converge at the mass of the intermediate vector boson W/sup +/-/. The coupling constants of the strong and weak interactions are derived in terms of the fine-structure constant α = 1/137
A wave equation interpolating between classical and quantum mechanics
Schleich, W. P.; Greenberger, D. M.; Kobe, D. H.; Scully, M. O.
2015-10-01
We derive a ‘master’ wave equation for a family of complex-valued waves {{Φ }}\\equiv R{exp}[{{{i}}S}({cl)}/{{\\hbar }}] whose phase dynamics is dictated by the Hamilton-Jacobi equation for the classical action {S}({cl)}. For a special choice of the dynamics of the amplitude R which eliminates all remnants of classical mechanics associated with {S}({cl)} our wave equation reduces to the Schrödinger equation. In this case the amplitude satisfies a Schrödinger equation analogous to that of a charged particle in an electromagnetic field where the roles of the scalar and the vector potentials are played by the classical energy and the momentum, respectively. In general this amplitude is complex and thereby creates in addition to the classical phase {S}({cl)}/{{\\hbar }} a quantum phase. Classical statistical mechanics, as described by a classical matter wave, follows from our wave equation when we choose the dynamics of the amplitude such that it remains real for all times. Our analysis shows that classical and quantum matter waves are distinguished by two different choices of the dynamics of their amplitudes rather than two values of Planck’s constant. We dedicate this paper to the memory of Richard Lewis Arnowitt—a pioneer of many-body theory, a path finder at the interface of gravity and quantum mechanics, and a true leader in non-relativistic and relativistic quantum field theory.
Statistical electromagnetics: Complex cavities
Naus, H.W.L.
2008-01-01
A selection of the literature on the statistical description of electromagnetic fields and complex cavities is concisely reviewed. Some essential concepts, for example, the application of the central limit theorem and the maximum entropy principle, are scrutinized. Implicit assumptions, biased
Broadband Electromagnetic Technology
2011-06-23
The objectives of this project are to continue the enhancements to the combined Broadband Electromagnetic and Full Encirclement Unit (BEM-FEU) technologies and to evaluate the systems capability in the laboratory and the field. The BEM instrument ...
Magnetorheological suspension electromagnetic brake
International Nuclear Information System (INIS)
Bica, Ioan
2004-01-01
The magnetorheological suspension (MRS) brake is of the monoblock type. The main part of the electromagnetic brake is an electromagnet, between whose poles two MRS disks are placed. For distances between disks of 0.65x10 -3 m±10%, revolutions of the electric motor, coupled to the electromagnetic brake, ranging between 200 and 1600 rev/min and braking powers of up to 85 W, there are no differences in revolutions between the disks of the electromagnetic brake. For fixed revolutions of the electric motor, the revolution of the parallel disk can be modified continuously by means of the intensity of the magnetic field. In all cases, the quantity of MRS is of 0.35x10 -3 kg
OPAL detector electromagnetic calorimeter
1988-01-01
Half of the electromagnetic calorimeter of the OPAL detector is seen in this photo. This calorimeter consists of 4720 blocks of lead glass. It was used to detect and measure the energy of photons, electrons and positrons by absorbing them.
Concise expression of a classical radiation spectrum
International Nuclear Information System (INIS)
Wang, C.
1993-01-01
In this paper we present a concise expression of the classical electromagnetic radiation spectrum of a moving charge. It is shown to be equivalent to the often used and much more complicated form derived from the Lienard-Wiechert potentials when the observation distance R satisfies the condition R much-gt γλ. The expression reveals a relationship between the radiation spectrum and the motion of the radiation source. It also forms the basis of an efficient computing approach, which is of practical value in numerical calculations of the spectral output of accelerated charges. The advantages of this approach for analytical and numerical applications are discussed and the bending-magnet synchrotron radiation spectrum is calculated according to the approach
Mathematics and electromagnetism
International Nuclear Information System (INIS)
Rodriguez Danta, M.
2000-01-01
Symbiosis between mathematics and electromagnetism is analyzed in a simple and concise manner by taking a historical perspective. The universal tool character of mathematical models allowed the transfer of models from several branches of physics into the realm of electromagnetism by drawing analogies. The mutual interdependence between covariant formulation and tensor calculus is marked. The paper focuses on the guiding idea of field theory and Maxwell's equations. Likewise, geometrization of interactions in connection with gauge fields is also noted. (Author)
The ATLAS electromagnetic calorimeter
Maximilien Brice
2003-01-01
Michel Mathieu, a technician for the ATLAS collaboration, is cabling the ATLAS electromagnetic calorimeter's first end-cap, before insertion into its cryostat. Millions of wires are connected to the electromagnetic calorimeter on this end-cap that must be carefully fed out from the detector so that data can be read out. Every element on the detector will be attached to one of these wires so that a full digital map of the end-cap can be recreated.
Electromagnetic Fields Exposure Limits
2018-01-01
Mr. T.P. (Tjerk) KUIPERS Senior Adviser Health Physics Military Healthcare & Occupational Health Expertise Co-ordination Centre Support...Test of Biological Integrity in Dogs Exposed to an Electromagnetic Pulse Environment”, Health Physics 36:159-165, 1979. [11] Baum, S.J., Ekstrom, M.E...Electromagnetic Radiation”, Health Physics 30:161-166, 1976. [12] Baum, S., Skidmore, W. and Ekstrom, M., “Continuous Exposure of Rodents to 108 Pulses
Electromagnetic Manifestation of Earthquakes
Uvarov Vladimir
2017-01-01
In a joint analysis of the results of recording the electrical component of the natural electromagnetic field of the Earth and the catalog of earthquakes in Kamchatka in 2013, unipolar pulses of constant amplitude associated with earthquakes were identified, whose activity is closely correlated with the energy of the electromagnetic field. For the explanation, a hypothesis about the cooperative character of these impulses is proposed.
Electromagnetic Manifestation of Earthquakes
Directory of Open Access Journals (Sweden)
Uvarov Vladimir
2017-01-01
Full Text Available In a joint analysis of the results of recording the electrical component of the natural electromagnetic field of the Earth and the catalog of earthquakes in Kamchatka in 2013, unipolar pulses of constant amplitude associated with earthquakes were identified, whose activity is closely correlated with the energy of the electromagnetic field. For the explanation, a hypothesis about the cooperative character of these impulses is proposed.
Electromagnetic reverberation chambers
Besnier, Philippe
2013-01-01
Dedicated to a complete presentation on all aspects of reverberation chambers, this book provides the physical principles behind these test systems in a very progressive manner. The detailed panorama of parameters governing the operation of electromagnetic reverberation chambers details various applications such as radiated immunity, emissivity, and shielding efficiency experiments.In addition, the reader is provided with the elements of electromagnetic theory and statistics required to take full advantage of the basic operational rules of reverberation chambers, including calibration proc
Quantum dynamics of classical stochastic systems
Energy Technology Data Exchange (ETDEWEB)
Casati, G
1983-01-01
It is shown that one hand Quantum Mechanics introduces limitations to the manifestations of chaotic motion resulting, for the case of the periodically kicked rotator, in the limitation of energy growth; also, as it is confirmed by numerical experiments, phenomena like the exponential instability of orbits, inherent to strongly chaotic systems, are absent here and therefore Quantum Mechanics appear to be more stable and predictable than Classical Mechanics. On the other hand, we have seen that nonrecurrent behavior may arise in Quantum Systems and it is connected to the presence of singular continuous spectrum. We conjecture that the classical chaotic behavior is reflected, at least partially, in the nature of the spectrum and the singular-continuity of the latter may possess a self-similar structure typical of classical chaos.
Directory of Open Access Journals (Sweden)
Laurent Chusseau
2013-02-01
Full Text Available We show that the thermodynamics of ideal gases may be derived solely from the Democritean concept of corpuscles moving in vacuum plus a principle of simplicity, namely that these laws are independent of the laws of motion, aside from the law of energy conservation. Only a single corpuscle in contact with a heat bath submitted to a z and t-invariant force is considered. Most of the end results are known but the method appears to be novel. The mathematics being elementary, the present paper should facilitate the understanding of the ideal gas law and of classical thermodynamics even though not-usually-taught concepts are being introduced.
Institute of Scientific and Technical Information of China (English)
2002-01-01
FIVE years ago, an ancient Chinese air was beamed to outer space as a PR exercise. To humankind, music is a universal language, so the tune seemed an ideal medium for communication with extraterrestrial intelligence. So far there has been no response, but it is believed that the tune will play for a billion years, and eventually be heard and understood. The melody is called High Mountain and Flowing Stream, and it is played on the guqin, a seven-stringed classical musical instrument similar to the zither.
Electromagnetic processes and interactions
International Nuclear Information System (INIS)
Scheck, F.
1983-01-01
The electron and muon are important tools in testing the structure of the fundamental electromagnetic interactions. On the other hand, if these interactions are known, they serve as ideal probes for the internal structure of complex hadronic targets such as nucleons and nuclei. Purely electromagnetic interactions play a distinctive role, for obvious experimental reasons: At low and intermediate energies the effective electromagnetic coupling is larger by many orders of magnitude than the weak couplings, so that electromagnetic processes are measurable to much higher accuracy than purely weak processes. The present chapter deals primarily with applications of charged leptons to problems of nucleon and nuclear structure, and to selected precision tests of quantum electrodynamics (QED) at low momentum transfers. In most of these applications the electromagnetic interactions effectively appear in the form of external fields in the leptonic particle's Dirac equation. This is the domain where the physics of (electromagnetically) interacting leptons can still be described in the framework of an effective, though relativistic, single particle theory. (orig.)
Covariant electromagnetic field lines
Hadad, Y.; Cohen, E.; Kaminer, I.; Elitzur, A. C.
2017-08-01
Faraday introduced electric field lines as a powerful tool for understanding the electric force, and these field lines are still used today in classrooms and textbooks teaching the basics of electromagnetism within the electrostatic limit. However, despite attempts at generalizing this concept beyond the electrostatic limit, such a fully relativistic field line theory still appears to be missing. In this work, we propose such a theory and define covariant electromagnetic field lines that naturally extend electric field lines to relativistic systems and general electromagnetic fields. We derive a closed-form formula for the field lines curvature in the vicinity of a charge, and show that it is related to the world line of the charge. This demonstrates how the kinematics of a charge can be derived from the geometry of the electromagnetic field lines. Such a theory may also provide new tools in modeling and analyzing electromagnetic phenomena, and may entail new insights regarding long-standing problems such as radiation-reaction and self-force. In particular, the electromagnetic field lines curvature has the attractive property of being non-singular everywhere, thus eliminating all self-field singularities without using renormalization techniques.
Electromagnetic cellular interactions.
Cifra, Michal; Fields, Jeremy Z; Farhadi, Ashkan
2011-05-01
Chemical and electrical interaction within and between cells is well established. Just the opposite is true about cellular interactions via other physical fields. The most probable candidate for an other form of cellular interaction is the electromagnetic field. We review theories and experiments on how cells can generate and detect electromagnetic fields generally, and if the cell-generated electromagnetic field can mediate cellular interactions. We do not limit here ourselves to specialized electro-excitable cells. Rather we describe physical processes that are of a more general nature and probably present in almost every type of living cell. The spectral range included is broad; from kHz to the visible part of the electromagnetic spectrum. We show that there is a rather large number of theories on how cells can generate and detect electromagnetic fields and discuss experimental evidence on electromagnetic cellular interactions in the modern scientific literature. Although small, it is continuously accumulating. Copyright © 2010 Elsevier Ltd. All rights reserved.
Quantum flesh on classical bones: Semiclassical bridges across the quantum-classical divide
Energy Technology Data Exchange (ETDEWEB)
Bokulich, Alisa [Center for Philosophy and History of Science, Boston University, Boston, MA (United States)
2014-07-01
Traditionally quantum mechanics is viewed as having made a sharp break from classical mechanics, and the concepts and methods of these two theories are viewed as incommensurable with one another. A closer examination of the history of quantum mechanics, however, reveals that there is a strong sense in which quantum mechanics was built on the backbone of classical mechanics. As a result, there is a considerable structural continuity between these two theories, despite their important differences. These structural continuities provide a ground for semiclassical methods in which classical structures, such as trajectories, are used to investigate and model quantum phenomena. After briefly tracing the history of semiclassical approaches, I show how current research in semiclassical mechanics is revealing new bridges across the quantum-classical divide.
International Nuclear Information System (INIS)
Agarwal, G S; Huang, Sumei
2014-01-01
We demonstrate the existence of the phenomenon of the inverse electromagnetically induced transparency (IEIT) in an opto mechanical system consisting of a nanomechanical mirror placed in an optical cavity. We show that two weak counter-propagating identical classical probe fields can be completely absorbed by the system in the presence of a strong coupling field so that the output probe fields are zero. The light is completely confined inside the cavity and the energy of the incoming probe fields is shared between the cavity field and creation of a coherent phonon and resides primarily in one of the polariton modes. The energy can be extracted by a perturbation of the external fields or by suddenly changing the Q of the cavity. (paper)
Influence of the electromagnetic parameters on the surface wave attenuation in thin absorbing layers
Li, Yinrui; Li, Dongmeng; Wang, Xian; Nie, Yan; Gong, Rongzhou
2018-05-01
This paper describes the relationships between the surface wave attenuation properties and the electromagnetic parameters of radar absorbing materials (RAMs). In order to conveniently obtain the attenuation constant of TM surface waves over a wide frequency range, the simplified dispersion equations in thin absorbing materials were firstly deduced. The validity of the proposed method was proved by comparing with the classical dispersion equations. Subsequently, the attenuation constants were calculated separately for the absorbing layers with hypothetical relative permittivity and permeability. It is found that the surface wave attenuation properties can be strongly tuned by the permeability of RAM. Meanwhile, the permittivity should be appropriate so as to maintain high cutoff frequency. The present work provides specific methods and designs to improve the attenuation performances of radar absorbing materials.
Electromagnetic damping of neutron star oscillations
International Nuclear Information System (INIS)
McDermott, P.N.; Savedoff, M.P.; Van Horn, H.M.; Zweibel, E.G.; Hansen, C.J.
1984-01-01
Nonradial pulsations of a neutron star with a strong dipole magnetic field cause emission of electromagnetic radiation. Here we compute the power radiated to vacuum by neutron star g-mode pulsations and by torsional oscillations of the neutron star crust. For the low-order quadrupole fluid g-modes we have considered, we find electromagnetic damping to be considerably more effective than gravitational radiation. For example, a 0.5 M/sub sun/ neutron star with a core temperature approx.10 7 K has a g 1 -mode period of 371 ms; for this mode were find the electromagnetic damping time to be tau/sub FM/approx.0.3 s, assuming the surface magnetic field strength of the neutron star to be B 0 approx.10 12 gauss. This is considerably less than the corresponding gravitational radiation time tau/sub GR/approx.3 x 10 17 yr. For dipole g-mode oscillations, there is no gravitational radiation, but electromagnetic damping and ohmic dissipation are efficient damping mechanisms. For dipole torsional oscillations, we find that electromagnetic damping again dominates, with tau/sub EM/approx.5 yr. Among the cases we have studied, quadrupole torsional oscillations appear to be dominated by gravitational radiation damping, with tau/sub GR/approx.10 4 yr, as compared with tau/sub EM/approx.2 x 10 7 yr
International Nuclear Information System (INIS)
Caldirola, P.; Recami, E.
1978-01-01
By assuming covariance of physical laws under (discrete) dilatations, strong and gravitational interactions have been described in a unified way. In terms of the (additional, discrete) ''dilatational'' degree of freedom, our cosmos as well as hadrons can be considered as different states of the same system, or rather as similar systems. Moreover, a discrete hierarchy can be defined of ''universes'' which are governed by force fields with strengths inversely proportional to the ''universe'' radii. Inside each ''universe'' an equivalence principle holds, so that its characteristic field can be geometrized there. It is thus easy to derive a whole ''numerology'', i.e. relations among numbers analogous to the so-called Weyl-Eddington-Dirac ''large numbers''. For instance, the ''Planck mass'' happens to be nothing but the (average) magnitude of the strong charge of the hadron quarks. However, our ''numerology'' connects the (gravitational) macrocosmos with the (strong) microcosmos, rather than with the electromagnetic ones (as, e.g., in Dirac's version). Einstein-type scaled equations (with ''cosmological'' term) are suggested for the hadron interior, which - incidentally - yield a (classical) quark confinement in a very natural way and are compatible with the ''asymptotic freedom''. At last, within a ''bi-scale'' theory, further equations are proposed that provide a priori a classical field theory of strong interactions (between different hadrons). The relevant sections are 5.2, 7 and 8. (author)
Electromagnetic acceleration studies with augmented rails
International Nuclear Information System (INIS)
Maruo, T.; Fujioka, K.; Nagaoka, K.; Okamoto, A.; Ikuta, K.; Nemoto, K.
1991-01-01
A comparative study of electromagnetic acceleration in the rail-type accelerators with two kinds of rail geometry was carried out experimentally. The accelerators were energized by 200kJ capacitor bank and the weight of loaded projectiles was about 1.3 grams with 10mm x 10mm square bore. The attained velocity was 4.3km/s in the augmented accelerator, while it was 3.8km/s in the classical device. In this paper these differences in attained velocity are briefly discussed. A theoretical understanding of the rail erosion is also described
Electromagnetism and the structure of matter
Funaro, Daniele
2008-01-01
The classical theory of electromagnetism is entirely revised in this book by proposing a variant of Maxwell equations that allows solitonic solutions (photons). The Lagrangian is the standard one, but it is minimized on a constrained space that enforces the wave packets to follow the rules of geometrical optics. Exact solutions are explicitly shown; this opens a completely new perspective for the study of light wave phenomena. In the framework of general relativity, the equations are written in covariant form. A coupling with the metric is obtained through the Einstein equation, whose solution
Electromagnetic fields with vanishing quantum corrections
Ortaggio, Marcello; Pravda, Vojtěch
2018-04-01
We show that a large class of null electromagnetic fields are immune to any modifications of Maxwell's equations in the form of arbitrary powers and derivatives of the field strength. These are thus exact solutions to virtually any generalized classical electrodynamics containing both non-linear terms and higher derivatives, including, e.g., non-linear electrodynamics as well as QED- and string-motivated effective theories. This result holds not only in a flat or (anti-)de Sitter background, but also in a larger subset of Kundt spacetimes, which allow for the presence of aligned gravitational waves and pure radiation.
Jinzenji, Masao
2018-01-01
This book furnishes a brief introduction to classical mirror symmetry, a term that denotes the process of computing Gromov–Witten invariants of a Calabi–Yau threefold by using the Picard–Fuchs differential equation of period integrals of its mirror Calabi–Yau threefold. The book concentrates on the best-known example, the quintic hypersurface in 4-dimensional projective space, and its mirror manifold. First, there is a brief review of the process of discovery of mirror symmetry and the striking result proposed in the celebrated paper by Candelas and his collaborators. Next, some elementary results of complex manifolds and Chern classes needed for study of mirror symmetry are explained. Then the topological sigma models, the A-model and the B-model, are introduced. The classical mirror symmetry hypothesis is explained as the equivalence between the correlation function of the A-model of a quintic hyper-surface and that of the B-model of its mirror manifold. On the B-model side, the process of construct...
Friedmann-Bette, B
2008-08-01
For more than 40 years, the effects of classical altitude training on sea-level performance have been the subject of many scientific investigations in individual endurance sports. To our knowledge, no studies have been performed in team sports like football. Two well-controlled studies showed that living and training at an altitude of >or=1800-2700 m for 3-4 weeks is superior to equivalent training at sea level in well-trained athletes. Most of the controlled studies with elite athletes did not reveal such an effect. However, the results of some uncontrolled studies indicate that sea-level performance might be enhanced after altitude training also in elite athletes. Whether hypoxia provides an additional stimulus for muscular adaptation, when training is performed with equal intensity compared with sea-level training is not known. There is some evidence for an augmentation of total hemoglobin mass after classical altitude training with duration >or=3 weeks at an altitude >or=2000 m due to altitude acclimatization. Considerable individual variation is observed in the erythropoietic response to hypoxia and in the hypoxia-induced reduction of aerobic performance capacity during training at altitude, both of which are thought to contribute to inter-individual variation in the improvement of sea-level performance after altitude training.
International Nuclear Information System (INIS)
Barra, F.; Gaspard, P.
2001-01-01
We consider the classical evolution of a particle on a graph by using a time-continuous Frobenius-Perron operator that generalizes previous propositions. In this way, the relaxation rates as well as the chaotic properties can be defined for the time-continuous classical dynamics on graphs. These properties are given as the zeros of some periodic-orbit zeta functions. We consider in detail the case of infinite periodic graphs where the particle undergoes a diffusion process. The infinite spatial extension is taken into account by Fourier transforms that decompose the observables and probability densities into sectors corresponding to different values of the wave number. The hydrodynamic modes of diffusion are studied by an eigenvalue problem of a Frobenius-Perron operator corresponding to a given sector. The diffusion coefficient is obtained from the hydrodynamic modes of diffusion and has the Green-Kubo form. Moreover, we study finite but large open graphs that converge to the infinite periodic graph when their size goes to infinity. The lifetime of the particle on the open graph is shown to correspond to the lifetime of a system that undergoes a diffusion process before it escapes
Mixed quantum-classical electrodynamics: Understanding spontaneous decay and zero-point energy
Li, Tao E.; Nitzan, Abraham; Sukharev, Maxim; Martinez, Todd; Chen, Hsing-Ta; Subotnik, Joseph E.
2018-03-01
The dynamics of an electronic two-level system coupled to an electromagnetic field are simulated explicitly for one- and three-dimensional systems through semiclassical propagation of the Maxwell-Liouville equations. We consider three flavors of mixed quantum-classical dynamics: (i) the classical path approximation (CPA), (ii) Ehrenfest dynamics, and (iii) symmetrical quasiclassical (SQC) dynamics. Our findings are as follows: (i) The CPA fails to recover a consistent description of spontaneous emission, (ii) a consistent "spontaneous" emission can be obtained from Ehrenfest dynamics, provided that one starts in an electronic superposition state, and (iii) spontaneous emission is always obtained using SQC dynamics. Using the SQC and Ehrenfest frameworks, we further calculate the dynamics following an incoming pulse, but here we find very different responses: SQC and Ehrenfest dynamics deviate sometimes strongly in the calculated rate of decay of the transient excited state. Nevertheless, our work confirms the earlier observations by Miller [J. Chem. Phys. 69, 2188 (1978), 10.1063/1.436793] that Ehrenfest dynamics can effectively describe some aspects of spontaneous emission and highlights interesting possibilities for studying light-matter interactions with semiclassical mechanics.
Classical Trajectories and Quantum Spectra
Mielnik, Bogdan; Reyes, Marco A.
1996-01-01
A classical model of the Schrodinger's wave packet is considered. The problem of finding the energy levels corresponds to a classical manipulation game. It leads to an approximate but non-perturbative method of finding the eigenvalues, exploring the bifurcations of classical trajectories. The role of squeezing turns out decisive in the generation of the discrete spectra.
Strong beam production for some elements
International Nuclear Information System (INIS)
Camplan, J.; Chaumont, J.; Meunier, R.
1974-01-01
Three electromagnetic isotope separators are installed in Rene Bernas Laboratory, one being especially adapted to ion implantation. The three apparatus use the same type of ion source and system of beam extraction. The special ion source is distinguishable from the others only by its smaller dimensions. These sources allow strong currents to be obtained for almost every element. The source and its extraction system are briefly described, examples of beams obtained are given [fr
Electromagnetic radiation accompanying gravitational waves from black hole binaries
Energy Technology Data Exchange (ETDEWEB)
Dolgov, A. [Dept. of Physics, Novosibirsk State University, Pirogova 2, 630090 Novosibirsk (Russian Federation); Postnov, K., E-mail: dolgov@fe.infn.it, E-mail: kpostnov@gmail.com [Sternberg Astronomical Institute, Moscow M.V. Lomonosov State University, Universitetskij pr. 13, 119234 Moscow (Russian Federation)
2017-09-01
The transition of powerful gravitational waves, created by the coalescence of massive black hole binaries, into electromagnetic radiation in external magnetic fields is considered. In contrast to the previous calculations of the similar effect we study the realistic case of the gravitational radiation frequency below the plasma frequency of the surrounding medium. The gravitational waves propagating in the plasma constantly create electromagnetic radiation dragging it with them, despite the low frequency. The plasma heating by the unattenuated electromagnetic wave may be significant in hot rarefied plasma with strong magnetic field and can lead to a noticeable burst of electromagnetic radiation with higher frequency. The graviton-to-photon conversion effect in plasma is discussed in the context of possible electromagnetic counterparts of GW150914 and GW170104.
Electromagnetic radiation accompanying gravitational waves from black hole binaries
International Nuclear Information System (INIS)
Dolgov, A.; Postnov, K.
2017-01-01
The transition of powerful gravitational waves, created by the coalescence of massive black hole binaries, into electromagnetic radiation in external magnetic fields is considered. In contrast to the previous calculations of the similar effect we study the realistic case of the gravitational radiation frequency below the plasma frequency of the surrounding medium. The gravitational waves propagating in the plasma constantly create electromagnetic radiation dragging it with them, despite the low frequency. The plasma heating by the unattenuated electromagnetic wave may be significant in hot rarefied plasma with strong magnetic field and can lead to a noticeable burst of electromagnetic radiation with higher frequency. The graviton-to-photon conversion effect in plasma is discussed in the context of possible electromagnetic counterparts of GW150914 and GW170104.
Dynamics of classical and quantum fields an introduction
Setlur, Girish S
2014-01-01
Dynamics of Classical and Quantum Fields: An Introduction focuses on dynamical fields in non-relativistic physics. Written by a physicist for physicists, the book is designed to help readers develop analytical skills related to classical and quantum fields at the non-relativistic level, and think about the concepts and theory through numerous problems. In-depth yet accessible, the book presents new and conventional topics in a self-contained manner that beginners would find useful. A partial list of topics covered includes: Geometrical meaning of Legendre transformation in classical mechanics Dynamical symmetries in the context of Noether's theorem The derivation of the stress energy tensor of the electromagnetic field, the expression for strain energy in elastic bodies, and the Navier Stokes equation Concepts of right and left movers in case of a Fermi gas explained Functional integration is interpreted as a limit of a sequence of ordinary integrations Path integrals for one and two quantum particles and for...
International Nuclear Information System (INIS)
Pennington, Michael
2011-01-01
The Schwinger-Dyson, Bethe-Salpeter system of equations are the link between coloured quarks and gluons, and colourless hadrons and their properties. This talk reviews some aspects of these studies from the infrared behavior of ghosts to the prediction of electromagnetic form-factors.
Induced photoassociation in the field of a strong electomagnetic wave
International Nuclear Information System (INIS)
Zaretskij, D.F.; Lomonosov, V.V.; Lyul'ka, V.A.
1979-01-01
The quantum-mechanical problem of the stimulated transition of a system in the field of a strong electromagnetic wave from the continuous spectrum to a bound state possessing a finite lifetime is considered. The expressions obtained are employed to calculate stimulated production of mesic atoms and mesic molecules (ddμ). It is demonstrated that in an external electromagnetic field the probability for production of this type may considerably increase
Classical and quantum cosmology
Calcagni, Gianluca
2017-01-01
This comprehensive textbook is devoted to classical and quantum cosmology, with particular emphasis on modern approaches to quantum gravity and string theory and on their observational imprint. It covers major challenges in theoretical physics such as the big bang and the cosmological constant problem. An extensive review of standard cosmology, the cosmic microwave background, inflation and dark energy sets the scene for the phenomenological application of all the main quantum-gravity and string-theory models of cosmology. Born of the author's teaching experience and commitment to bridging the gap between cosmologists and theoreticians working beyond the established laws of particle physics and general relativity, this is a unique text where quantum-gravity approaches and string theory are treated on an equal footing. As well as introducing cosmology to undergraduate and graduate students with its pedagogical presentation and the help of 45 solved exercises, this book, which includes an ambitious bibliography...
International Nuclear Information System (INIS)
Sbisà, Fulvio
2015-01-01
The aim of these notes is to provide a self-contained review of why it is generically a problem when a solution of a theory possesses ghost fields among the perturbation modes. We define what a ghost field is and we show that its presence is associated with a classical instability whenever the ghost field interacts with standard fields. We then show that the instability is more severe at quantum level, and that perturbative ghosts can exist only in low energy effective theories. However, if we do not consider very ad hoc choices, compatibility with observational constraints implies that low energy effective ghosts can exist only at the price of giving up Lorentz invariance or locality above the cut-off, in which case the cut-off has to be much lower that the energy scales we currently probe in particle colliders. We also comment on the possible role of extra degrees of freedom which break Lorentz invariance spontaneously. (paper)
Classical mechanics with Mathematica
Romano, Antonio
2018-01-01
This textbook takes a broad yet thorough approach to mechanics, aimed at bridging the gap between classical analytic and modern differential geometric approaches to the subject. Developed by the authors from over 30 years of teaching experience, the presentation is designed to give students an overview of the many different models used through the history of the field—from Newton to Hamilton—while also painting a clear picture of the most modern developments. The text is organized into two parts. The first focuses on developing the mathematical framework of linear algebra and differential geometry necessary for the remainder of the book. Topics covered include tensor algebra, Euclidean and symplectic vector spaces, differential manifolds, and absolute differential calculus. The second part of the book applies these topics to kinematics, rigid body dynamics, Lagrangian and Hamiltonian dynamics, Hamilton–Jacobi theory, completely integrable systems, statistical mechanics of equilibrium, and impulsive dyna...
Mechanical Systems, Classical Models
Teodorescu, Petre P
2009-01-01
This third volume completes the Work Mechanical Systems, Classical Models. The first two volumes dealt with particle dynamics and with discrete and continuous mechanical systems. The present volume studies analytical mechanics. Topics like Lagrangian and Hamiltonian mechanics, the Hamilton-Jacobi method, and a study of systems with separate variables are thoroughly discussed. Also included are variational principles and canonical transformations, integral invariants and exterior differential calculus, and particular attention is given to non-holonomic mechanical systems. The author explains in detail all important aspects of the science of mechanics, regarded as a natural science, and shows how they are useful in understanding important natural phenomena and solving problems of interest in applied and engineering sciences. Professor Teodorescu has spent more than fifty years as a Professor of Mechanics at the University of Bucharest and this book relies on the extensive literature on the subject as well as th...
Quantum models of classical systems
International Nuclear Information System (INIS)
Hájíček, P
2015-01-01
Quantum statistical methods that are commonly used for the derivation of classical thermodynamic properties are extended to classical mechanical properties. The usual assumption that every real motion of a classical mechanical system is represented by a sharp trajectory is not testable and is replaced by a class of fuzzy models, the so-called maximum entropy (ME) packets. The fuzzier are the compared classical and quantum ME packets, the better seems to be the match between their dynamical trajectories. Classical and quantum models of a stiff rod will be constructed to illustrate the resulting unified quantum theory of thermodynamic and mechanical properties. (paper)
Directory of Open Access Journals (Sweden)
Maryann Wilson
2013-01-01
Full Text Available BACKGROUND: The impact of a scientific article is proportional to the citations it has received. In this study, we set out to identify the most cited works in epileptology in order to evaluate research trends in this field. METHODS: According to the Web of Science database, articles with more than 400 citations qualify as "citation classics". We conducted a literature search on the ISI Web of Science bibliometric database for scientific articles relevant to epilepsy. RESULTS: We retrieved 67 highly cited articles (400 or more citations, which were published in 31 journals: 17 clinical studies, 42 laboratory studies, 5 reviews and 3 classification articles. Clinical studies consisted of epidemiological analyses (n=3, studies on the clinical phenomenology of epilepsy (n=5 – including behavioral and prognostic aspects – and articles focusing on pharmacological (n=6 and non-pharmacological (n=3 treatment. The laboratory studies dealt with genetics (n=6, animal models (n=27, and neurobiology (n=9 – including both neurophysiology and neuropathology studies. The majority (61% of citation classics on epilepsy were published after 1986, possibly reflecting the expansion of research interest in laboratory studies driven by the development of new methodologies, specifically in the fields of genetics and animal models. Consequently, clinical studies were highly cited both before and after the mid 80s, whilst laboratory researches became widely cited after 1990. CONCLUSIONS: Our study indicates that the main drivers of scientific impact in the field of epileptology have increasingly become genetic and neurobiological studies, along with research on animal models of epilepsy. These articles are able to gain the highest numbers of citations in the time span of a few years and suggest potential directions for future research.
Electromagnetic probes of the QGP
Directory of Open Access Journals (Sweden)
Bratkovskaya E. L.
2015-01-01
Full Text Available We investigate the properties of the QCD matter across the deconfinement phase transition in the scope of the parton-hadron string dynamics (PHSD transport approach. We present here in particular the results on the electromagnetic radiation, i.e. photon and dilepton production, in relativistic heavy-ion collisions. By comparing our calculations for the heavy-ion collisions to the available data, we determine the relative importance of the various production sources and address the possible origin of the observed strong elliptic flow v2 of direct photons. We argue that the different centrality dependence of the hadronic and partonic sources for direct photon production in nucleusnucleus collisions can be employed to shed some more light on the origin of the photon v2 “puzzle”. While the dilepton spectra at low invariant mass show in-medium effects like an enhancement from multiple baryonic resonance formation or a collisional broadening of the vector meson spectral functions, the dilepton yield at high invariant masses (above 1.1 GeV is dominated by QGP contributions for central heavy-ion collisions at ultra-relativistic energies. This allows to have an independent view on the parton dynamics via their electromagnetic massive radiation.
Electromagnetic field effects in explosives
Tasker, Douglas
2009-06-01
Present and previous research on the effects of electromagnetic fields on the initiation and detonation of explosives and the electromagnetic properties of explosives are reviewed. Among the topics related to detonating explosives are: measurements of conductivity; enhancement of performance; and control of initiation and growth of reaction. Hayes...()^1 showed a strong correlation of peak electrical conductivity with carbon content of the detonation products. Ershov.......^2 linked detailed electrical conductivity measurements with reaction kinetics and this work was extended to enhance detonation performance electrically;...^3 for this, electrical power densities of the order of 100 TW/m^2 of explosive surface normal to the detonation front were required. However, small electrical powers are required to affect the initiation and growth of reaction.......^4,5 A continuation of this work will be reported. LA-UR 09-00873 .^1 B. Hayes, Procs. of 4th Symposium (International) on Detonation (1965), p. 595. ^2 A. Ershov, P. Zubkov, and L. Luk'yanchikov, Combustion, Explosion, and Shock Waves 10, 776-782 (1974). ^3 M. Cowperthwaite, Procs. 9th Detonation Symposium (1989), p. 388-395. ^4 M. A. Cook and T. Z. Gwyther, ``Influence of Electric Fields on Shock to Detonation Transition,'' (1965). ^5 D. Salisbury, R. Winter, and L. Biddle, Procs. of the APS Topical Conference on Shock Compression of Condensed Matter (2005) p. 1010-1013.
BETA (Bitter Electromagnet Testing Apparatus)
Bates, Evan M.; Birmingham, William J.; Rivera, William F.; Romero-Talamas, Carlos A.
2017-10-01
The Bitter Electromagnet Testing Apparatus (BETA) is a 1-Tesla (T) prototype of the 10-T Adjustable Long Pulse High-Field Apparatus (ALPHA). These water-cooled resistive magnets use high DC currents to produce strong uniform magnetic fields. Presented here is the successful completion of the BETA project and experimental results validating analytical magnet designing methods developed at the Dusty Plasma Laboratory (DPL). BETA's final design specifications will be highlighted which include electromagnetic, thermal and stress analyses. The magnet core design will be explained which include: Bitter Arcs, helix starters, and clamping annuli. The final version of the magnet's vessel and cooling system are also presented, as well as the electrical system of BETA, which is composed of a unique solid-state breaker circuit. Experimental results presented will show the operation of BETA at 1 T. The results are compared to both analytical design methods and finite element analysis calculations. We also explore the steady state maximums and theoretical limits of BETA's design. The completion of BETA validates the design and manufacturing techniques that will be used in the succeeding magnet, ALPHA.
Electromagnetic radiation optimum neutralizer
International Nuclear Information System (INIS)
Smirnov, Igor
2002-01-01
This particular article relates to subtle electrical effects, and provides some evidence of a fundamental nature on how subtle low frequency electromagnetic fields might be utilized to protect human body against harmful effects of high frequencies electromagnetic radiation. I have focused my efforts on definite polar polymer compound named EMRON which is patented in the USA. This polar polymer compound can be excited by external high frequencies electromagnetic fields to generate subtle low frequency oscillations that are beneficial for cellular life structures. This concept is based on the possibility of existence of resonance phenomenon between polar polymers and biopolymers such as proteins, nucleic acids, lipids, etc. Low frequency patterns generated by defined polar polymer compound can interact with biostructures and transmit the signals that support and improve cellular functions in the body. The mechanism of this process was confirmed by number of studies. The animal (including human) brain is affected by electromagnetic waves to the extent that production of Alpha or Theta waves can be directly induced into brain by carrying an ELF (extremely low frequency, 5-12 Hz) signal on a microwave carrier frequency. EMRON does not reduce the power of electromagnetic fields. It 'shields' the cellular structures of the body against the harmful effects of EMR. The radiation is still entering the body but the neutralizing effect of EMRON renders the radiation harmless
Vacuum in the presence of electromagnetic fields and rotating boundaries
International Nuclear Information System (INIS)
Manogue, C.A.
1984-01-01
Two investigations of the properties of the vacuum are made. The first is a reconsideration of the classic Klein paradox, particle creation due to the presence of very strong external electromagnetic potentials. Expectation values of the current, momentum, and number operators, each of which is a measure of particle creation, are calculated for both massive spin zero and massive spin one half fields. The relationship between super-radiance and pair creation is explained. A review of past work by other authors is included and common conceptual errors are pointed out. The second investigation concerns the rotation of the vacuum caused by the rotation of boundaries. Just as the presence of boundaries can create a change in the vacuum expectation value of the energy density (the Casimir effect), the rotation of such boundaries can create changes in the vacuum expectation value of the momentum density. Calculations of the Casimir effect are made for a massless scalar field confined to an infinitely long square box. The change in the vacuum expectation value of the momentum density is calculated if this same box is rotating around its long central axis. In contrast, it is shown that for an infinitely long circular cylinder there is no change in the momentum density
Classical limit of diagonal form factors and HHL correlators
Energy Technology Data Exchange (ETDEWEB)
Bajnok, Zoltan [MTA Lendület Holographic QFT Group, Wigner Research Centre,H-1525 Budapest 114, P.O.B. 49 (Hungary); Janik, Romuald A. [Institute of Physics, Jagiellonian University,ul. Łojasiewicza 11, 30-348 Kraków (Poland)
2017-01-16
We propose an expression for the classical limit of diagonal form factors in which we integrate the corresponding observable over the moduli space of classical solutions. In infinite volume the integral has to be regularized by proper subtractions and we present the one, which corresponds to the classical limit of the connected diagonal form factors. In finite volume the integral is finite and can be expressed in terms of the classical infinite volume diagonal form factors and subvolumes of the moduli space. We analyze carefully the periodicity properties of the finite volume moduli space and found a classical analogue of the Bethe-Yang equations. By applying the results to the heavy-heavy-light three point functions we can express their strong coupling limit in terms of the classical limit of the sine-Gordon diagonal form factors.
Electromagnetic fields and their impacts
Prša, M. A.; Kasaš-Lažetić, K. K.
2018-01-01
The main goal of this paper is to briefly recall some different electromagnetic field definitions, some macroscopic sources of electromagnetic fields, electromagnetic fields classification regarding time dependences, and the ways of field determination in concrete cases. After that, all the mechanisms of interaction between electromagnetic field and substance, on atomic level, are described in details. Interaction between substance and electric field is investigated separately from the substance and magnetic field interaction. It is demonstrated that, in all cases of the unique electromagnetic field, total interaction can be treated as a superposition of two separated interactions. Finally, the main electromagnetic fields surrounding us is cited and discussed.
International Nuclear Information System (INIS)
Cai Xun-Ming
2015-01-01
Electromagnetically induced transparency and absorption of a monochromatic light controlled by a radio frequency field in the cold multi-Zeeman-sublevel atoms are theoretically investigated. These Zeeman sublevels are coupled by a radio frequency (RF) field. Both electromagnetically induced transparency and electromagnetically induced absorption can be obtained by tuning the frequency of RF field for both the linear polarization and elliptical polarization monochromatic lights. When the transfer of coherence via spontaneous emission from the excited state to the ground state is considered, electromagnetically induced absorption can be changed into electromagnetically induced transparency with the change of intensity of radio field. The transparency windows controlled by the RF field can have potential applications in the magnetic-field measurement and quantum information processing. (electromagnetism, optics, acoustics, heat transfer, classical mechanics, and fluid dynamics)
Damping in accelerators due to classical radiation
International Nuclear Information System (INIS)
Mills, F.E.
1962-01-01
The rates of change of the magnitudes of the adiabatic invariants is calculated in the case of a Hamiltonian system subjected to generalized non conservative forces. These results are applied to the case of the classical radiation of electrons in an accelerator or storage ring. The resulting expressions for the damping rates of three independent oscillation modes suggest structures which are damping in all three modes, while at the same time allowing 'strong focussing' and the attendant strong momentum compaction. (author)
Electromagnetically induced transparency in high-temperature magnetoactive plasma
International Nuclear Information System (INIS)
Kryachko, A.Yu.; Litvak, A.G.; Tokman, M.D.
2002-01-01
The classical analog of the presently popular in the quantum electronics effect of the electromagnetically induced transparency (EIT) is studied. The EIT effect is considered for the electron-cyclotron waves in the plasma with the finite temperature. The expression for the effective index of the electromagnetic wave refraction is identified and the dispersion law and this wave absorption under the EIT conditions are studied. It is shown, that accounting for the thermal motion, which radically changes the behavior of the signal wave dispersion curves in the EIT area, as compared with the cold plasma case [ru
Gravitation and electromagnetism
Apsel, D
1979-01-01
Through an examination of the Bohm-Aharonov experiment, a new theory of gravitation and electromagnetism is proposed. The fundamental assumption of the theory is that the motion of a particle in a combination of gravitational and electromagnetic fields is determined from a variational principle of the form delta integral /sub A//sup B /d tau =0. The form of the physical time is determined from an examination of the Maxwell-Einstein action function. The field and motion equations are formally identical to those of Maxwell-Einstein theory. The theory predicts that even in a field-free region of space, electromagnetic potentials can alter the phase of a wave function and the lifetime of a charged particle. The phase alteration has been observed in the Bohm-Aharonov experiment. There is an indication that the lifetime alteration has shown up in a recent CERN storage ring experiment. Experimental tests are proposed. (11 refs).
Metamaterial electromagnetic wave absorbers.
Watts, Claire M; Liu, Xianliang; Padilla, Willie J
2012-06-19
The advent of negative index materials has spawned extensive research into metamaterials over the past decade. Metamaterials are attractive not only for their exotic electromagnetic properties, but also their promise for applications. A particular branch-the metamaterial perfect absorber (MPA)-has garnered interest due to the fact that it can achieve unity absorptivity of electromagnetic waves. Since its first experimental demonstration in 2008, the MPA has progressed significantly with designs shown across the electromagnetic spectrum, from microwave to optical. In this Progress Report we give an overview of the field and discuss a selection of examples and related applications. The ability of the MPA to exhibit extreme performance flexibility will be discussed and the theory underlying their operation and limitations will be established. Insight is given into what we can expect from this rapidly expanding field and future challenges will be addressed. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Electromagnetic theory for filamentary superconductors
International Nuclear Information System (INIS)
Carr, W.J. Jr.
1975-01-01
It is shown that a multifilament superconductor, made up of a bundle of twisted filaments embedded in a normal matrix, can be treated as a new state of matter with anisotropic electrical and magnetic properties. Macroscopic electromagnetic field vectors, which satisfy Maxwell's equations, are defined in terms of averages over the ''microscopic'' fields. However, the sources for the field, i.e., the current and charge densities and the magnetization and polarization, differ in some respects from those for ordinary matter. In particular, since the elementary magnetic dipole moments are distributed along lines rather than located at fixed points, the definition of the magnetization transverse to the filaments differs by a factor of 2 from that for ordinary matter, and the definition of the macroscopic current density is also slightly modified. Constitutive relationships among the field vectors in terms of permeabilities, dielectric constants, and conductivities are examined in the limits of strong and weak fields
The theory of electromagnetism
Jones, D S
1964-01-01
The Theory of the Electomagnetism covers the behavior of electromagnetic fields and those parts of applied mathematics necessary to discover this behavior. This book is composed of 11 chapters that emphasize the Maxwell's equations. The first chapter is concerned with the general properties of solutions of Maxwell's equations in matter, which has certain macroscopic properties. The succeeding chapters consider specific problems in electromagnetism, including the determination of the field produced by a variable charge, first in isolation and then in the surface distributions of an antenna. The
Das, Ashok
2013-01-01
These lecture notes on electromagnetism have evolved from graduate and undergraduate EM theory courses given by the author at the University of Rochester, with the basics presented with clarity and his characteristic attention to detail. The thirteen chapters cover, in logical sequence, topics ranging from electrostatics, magnetostatics and Maxwell's equations to plasmas and radiation. Boundary value problems are treated extensively, as are wave guides, electromagnetic interactions and fields. This second edition comprises many of the topics expanded with more details on the derivation of vari
Electromagnetic clutches and couplings
Vorob'Yeva, T M; Fry, D W; Higinbotham, W
2013-01-01
Electromagnetic Clutches and Couplings contains a detailed description of U.S.S.R. electromagnetic friction clutches, magnetic couplings, and magnetic particle couplings. This book is divided into four chapters. The first chapter discusses the design and construction of magnetic (solenoid-operated) couplings, which are very quick-acting devices and used in low power high-speed servo-systems. Chapter 2 describes the possible fields of application, design, construction, and utilization of magnetic particle couplings. The aspects of construction, design, and utilization of induction clutches (sli
Essentials of Computational Electromagnetics
Sheng, Xin-Qing
2012-01-01
Essentials of Computational Electromagnetics provides an in-depth introduction of the three main full-wave numerical methods in computational electromagnetics (CEM); namely, the method of moment (MoM), the finite element method (FEM), and the finite-difference time-domain (FDTD) method. Numerous monographs can be found addressing one of the above three methods. However, few give a broad general overview of essentials embodied in these methods, or were published too early to include recent advances. Furthermore, many existing monographs only present the final numerical results without specifyin
The stability of the strong gravity solution
International Nuclear Information System (INIS)
Baran, S.A.
1978-01-01
The perturbation of the classical solution to a strong gravity model given by Salam and Strathdee is investigated. Using the Hamiltonian formalism it is shown that this static and spherically symmetric solution is stable under the odd parity perturbations provided some parameters in the solution are suitably restricted
Electromagnetic fields on a quantum scale. I.
Grimes, Dale M; Grimes, Craig A
2002-10-01
This is the first in a series of two articles, the second of which provides an exact electro-magnetic field description of photon emission, absorption, and radiation pattern. Photon energy exchanges are analyzed and shown to be the triggered, regenerative response of a non-local eigenstate electron. This first article presents a model-based, hidden variable analysis of quantum theory that provides the statistical nature of wave functions. The analysis uses the equations of classical electro-magnetism and conservation of energy while modeling an eigenstate electron as a nonlocal entity. Essential to the analysis are physical properties that were discovered and analyzed only after the historical interpretation of quantum mechanics was established: electron non-locality and the standing electro-magnetic energy that accompanies and encompasses an active, electrically small volume. The standing energy produces a driving radiation reaction force that, under certain circumstances, is many orders of magnitude larger than currently accepted values. These properties provide a sufficient basis for the Schrödinger equation as a descriptor of non-relativistic eigenstate electrons in or near equilibrium. The uncertainty principle follows, as does the exclusion principle. The analysis leads to atomic stability and causality in the sense that the status of physical phenomena at any instant specifies the status an instant later.
Electromagnetic Fields in Reverberant Environments
Vogt-Ardatjew, Robert Andrzej
2017-01-01
The phenomenon of resonating electromagnetic (EM) fields has been commonly and successfully exploited in reverberation chambers (RC) for the purpose of electromagnetic compatibility (EMC) testing, as well as modeling multipath environments. Although largely successful, the currently used statistical
Electromagnetic fields in stratified media
Li, Kai
2009-01-01
Dealing with an important branch of electromagnetic theory with many useful applications in subsurface communication, radar, and geophysical prospecting and diagnostics, this book introduces electromagnetic theory and wave propagation in complex media.
Electromagnetic interference: a radiant future!
Leferink, Frank Bernardus Johannes
2015-01-01
Although Electromagnetic Interference and Electromagnetic Compatibility are well established domains, the introduction of new technologies results in new challenges. Changes in both measurement techniques, and technological trends resulting in new types of interference are described. These are the
Crowder, Martin J
2001-01-01
If something can fail, it can often fail in one of several ways and sometimes in more than one way at a time. There is always some cause of failure, and almost always, more than one possible cause. In one sense, then, survival analysis is a lost cause. The methods of Competing Risks have often been neglected in the survival analysis literature. Written by a leading statistician, Classical Competing Risks thoroughly examines the probability framework and statistical analysis of data of Competing Risks. The author explores both the theory of the subject and the practicalities of fitting the models to data. In a coherent, self-contained, and sequential account, the treatment moves from the bare bones of the Competing Risks setup and the associated likelihood functions through survival analysis using hazard functions. It examines discrete failure times and the difficulties of identifiability, and concludes with an introduction to the counting-process approach and the associated martingale theory.With a dearth of ...
Grafakos, Loukas
2014-01-01
The main goal of this text is to present the theoretical foundation of the field of Fourier analysis on Euclidean spaces. It covers classical topics such as interpolation, Fourier series, the Fourier transform, maximal functions, singular integrals, and Littlewood–Paley theory. The primary readership is intended to be graduate students in mathematics with the prerequisite including satisfactory completion of courses in real and complex variables. The coverage of topics and exposition style are designed to leave no gaps in understanding and stimulate further study. This third edition includes new Sections 3.5, 4.4, 4.5 as well as a new chapter on “Weighted Inequalities,” which has been moved from GTM 250, 2nd Edition. Appendices I and B.9 are also new to this edition. Countless corrections and improvements have been made to the material from the second edition. Additions and improvements include: more examples and applications, new and more relevant hints for the existing exercises, new exercises, and...
Classical tokamak transport theory
International Nuclear Information System (INIS)
Nocentini, Aldo
1982-01-01
A qualitative treatment of the classical transport theory of a magnetically confined, toroidal, axisymmetric, two-species plasma is presented. The 'weakly collisional' ('banana' and 'plateau') and 'collision dominated' ('Pfirsch-Schlueter' and 'highly collisional') regimes, as well as the Ware effect are discussed. The method used to evaluate the diffusion coffieicnts of particles and heat in the weakly collisional regime is based on stochastic argument, that requires an analysis of the characteristic collision frequencies and lengths for particles moving in a tokamak-like magnetic field. The same method is used to evaluate the Ware effect. In the collision dominated regime on the other hand, the particle and heat fluxes across the magnetic field lines are dominated by macroscopic effects so that, although it is possible to present them as diffusion (in fact, the fluxes turn out to be proportional to the density and temperature gradients), a macroscopic treatment is more appropriate. Hence, fluid equations are used to inveatigate the collision dominated regime, to which particular attention is devoted, having been shown relatively recently that it is more complicated than the usual Pfirsch-Schlueter regime. The whole analysis presented here is qualitative, aiming to point out the relevant physical mechanisms involved in the various regimes more than to develop a rigorous mathematical derivation of the diffusion coefficients, for which appropriate references are given. (author)
Sullivan, Woodruff Turner
1982-01-01
Radio techniques were the nrst to lead astronomy away from the quiescent and limited Universe revealed by traditional observations at optical wave lengths. In the earliest days of radio astronomy, a handful of radio physicists and engineers made one startling discovery after another as they opened up the radio sky. With this collection of classic papers and the extensive intro ductory material, the reader can experience these exciting discoveries, as well as understand the developing techniques and follow the motivations which prompted the various lines of inquiry. For instance he or she will follow in detail the several attempts to detect radio waves from the sun at the turn of the century; the unravelling by Jansky of a "steady hiss type static"; the incredible story of Reber who built a 9 meter dish in his backyard in 1937 and then mapped the Milky Way; the vital discoveries by Hey and colleagues of radio bursts from the Sun and of a discrete source in the constellation of Cygnus; the development of re...
Anomalous electromagnetic coupling via entanglement at the nanoscale
International Nuclear Information System (INIS)
Slepyan, Gregory; Boag, Amir; Mordachev, Vladimir; Sinkevich, Eugene; Maksimenko, Sergey; Kuzhir, Polina; Miano, Giovanni; Portnoi, Mikhail E; Maffucci, Antonio
2017-01-01
Understanding unwanted mutual interactions between devices at the nanoscale is crucial for the study of the electromagnetic compatibility in nanoelectronic and nanophotonic systems. Anomalous electromagnetic coupling (crosstalk) between nanodevices may arise from the combination of electromagnetic interaction and quantum entanglement. In this paper we study in detail the crosstalk between two identical nanodevices, each consisting of a quantum emitter (atom, quantum dot, etc), capacitively coupled to a pair of nanoelectrodes. Using the generalized susceptibility concept, the overall system is modeled as a two-port within the framework of the electrical circuit theory and it is characterized by the admittance matrix. We show that the entanglement changes dramatically the physical picture of the electromagnetic crosstalk. In particular, the excitation produced in one of the ports may be redistributed in equal parts between both the ports, in spite of the rather small electromagnetic interactions. Such an anomalous crosstalk is expected to appear at optical frequencies in lateral GaAs double quantum dots. A possible experimental set up is also discussed. The classical concepts of interference in the operation of electronic devices, which have been known since the early days of radio-communications and are associated with electromagnetic compatibility, should then be reconsidered at the nanoscale. (paper)
A semi-classical analysis of Dirac fermions in 2+1 dimensions
International Nuclear Information System (INIS)
Maiti, Moitri; Shankar, R
2012-01-01
We investigate the semi-classical dynamics of massless Dirac fermions in 2+1 dimensions in the presence of external electromagnetic fields. By generalizing the α matrices by two generators of the SU(2) group in the (2S + 1)-dimensional representation and doing a certain scaling, we formulate an S → ∞ limit where the orbital and the spinor degrees become classical. We solve for the classical trajectories for a free particle on a cylinder and a particle in a constant magnetic field. We compare the semi-classical spectrum, obtained by Bohr–Sommerfeld quantization with the exact quantum spectrum for low values of S. For the free particle, the semi-classical spectrum is exact. For the particle in a constant magnetic field, the semi-classical spectrum reproduces all the qualitative features of the exact quantum spectrum at all S. The quantitative fit for S = 1/2 is reasonably good. (paper)
Quantum symmetries of classical spaces
Bhowmick, Jyotishman; Goswami, Debashish; Roy, Subrata Shyam
2009-01-01
We give a general scheme for constructing faithful actions of genuine (noncommutative as $C^*$ algebra) compact quantum groups on classical topological spaces. Using this, we show that: (i) a compact connected classical space can have a faithful action by a genuine compact quantum group, and (ii) there exists a spectral triple on a classical connected compact space for which the quantum group of orientation and volume preserving isometries (in the sense of \\cite{qorient}) is a genuine quantum...
Dynamics of unitarization by classicalization
International Nuclear Information System (INIS)
Dvali, Gia; Pirtskhalava, David
2011-01-01
We study dynamics of the classicalization phenomenon suggested in G. Dvali et al. , according to which a class of non-renormalizable theories self-unitarizes at very high-energies via creation of classical configurations (classicalons). We study this phenomenon in an explicit model of derivatively-self-coupled scalar that serves as a prototype for a Nambu-Goldstone-Stueckelberg field. We prepare the initial state in form of a collapsing wave-packet of a small occupation number but of very high energy, and observe that the classical configuration indeed develops. Our results confirm the previous estimates, showing that because of self-sourcing the wave-packet forms a classicalon configuration with radius that increases with center of mass energy. Thus, classicalization takes place before the waves get any chance of probing short-distances. The self-sourcing by energy is the crucial point, which makes classicalization phenomenon different from the ordinary dispersion of the wave-packets in other interacting theories. Thanks to this, unlike solitons or other non-perturbative objects, the production of classicalons is not only unsuppressed, but in fact dominates the high-energy scattering. In order to make the difference between classicalizing and non-classicalizing theories clear, we use a language in which the scattering cross section in a generic theory can be universally understood as a geometric cross section set by a classical radius down to which waves can propagate freely, before being scattered. We then show, that in non-classicalizing examples this radius shrinks with increasing energy and becomes microscopic, whereas in classicalizing theories expands and becomes macroscopic. We study analogous scattering in a Galileon system and discover that classicalization also takes place there, although somewhat differently. We thus observe, that classicalization is source-sensitive and that Goldstones pass the first test.
Low frequency electromagnetic field sensor
International Nuclear Information System (INIS)
Zhu Min; Zhou Yan; He Yicheng; Zheng Zhenxing; Liu Sunkun
2000-01-01
The measurement technique of low frequency electromagnetic field is reported. According to this principle, the authors have designed a sensor, which is used to measure the natural electromagnetic field, SLEMP and electromagnetic signals generated by some explosions. The frequency band of this sensor is from 0.08 Hz to 2 MHz
Electromagnetic radiation detector
Benson, Jay L.; Hansen, Gordon J.
1976-01-01
An electromagnetic radiation detector including a collimating window, a cathode member having a photoelectric emissive material surface angularly disposed to said window whereby radiation is impinged thereon at acute angles, an anode, separated from the cathode member by an evacuated space, for collecting photoelectrons emitted from the emissive cathode surface, and a negatively biased, high transmissive grid disposed between the cathode member and anode.
Disconnected electromagnetic form factors
International Nuclear Information System (INIS)
Wilcox, Walter
2001-01-01
Preliminary results of a calculation of disconnected nucleon electromagnetic factors factors on the lattice are presented. The implementation of the numerical subtraction scheme is outlined. A comparison of results for electric and magnetic disconnected form factors on two lattice sizes with those of the Kentucky group is presented. Unlike previous results, the results found in this calculation are consistent with zero in these sectors
Electromagnetic distance measurement
1967-01-01
This book brings together the work of forty-eight geodesists from twenty-five countries. They discuss various new electromagnetic distance measurement (EDM) instruments - among them the Tellurometer, Geodimeter, and air- and satellite-borne systems - and investigate the complex sources of error.
Equivalence principles and electromagnetism
Ni, W.-T.
1977-01-01
The implications of the weak equivalence principles are investigated in detail for electromagnetic systems in a general framework. In particular, it is shown that the universality of free-fall trajectories (Galileo weak equivalence principle) does not imply the validity of the Einstein equivalence principle. However, the Galileo principle plus the universality of free-fall rotation states does imply the Einstein principle.
Electromagnetic Environments Simulator (EMES)
International Nuclear Information System (INIS)
Varnado, G.B.
1975-11-01
A multipurpose electromagnetic environments simulator has been designed to provide a capability for performing EMR, EMP, and lightning near stroke testing of systems, subsystems and components in a single facility. This report describes the final facility design and presents the analytical and experimental verification of the design
Pregnancy and electromagnetic fields
International Nuclear Information System (INIS)
Bisseriex, Ch.; Laurent, P.; Cabaret, Ph.; Bonnet, C.; Marteau, E.; Le Berre, G.; Tirlemont, S.; Castro, H.; Becker, A.; Demaret, Ph.; Donati, M.; Ganem, Y.; Moureaux, P.
2011-07-01
This document briefly indicates the status of knowledge regarding the effect of magnetic fields on biological tissues and pregnancy, outlines the lack of data on some frequencies and the weakness of studies on long term effects on child development. It evokes the issue of exposure assessment and that of identification of workstations exposed to electromagnetic fields
Electromagnetic structure of nuclei
International Nuclear Information System (INIS)
Arnold, R.G.
1986-07-01
A brief review is given of selected topics in the electromagnetic structure of nucleons and nuclei, including nucleon form factors from both quantum chromodynamics and electron scattering data, measurements of the deuteron and triton form factors, quasi-elastic scattering, and the EMC effect. 47 refs., 13 figs
"Hearing" Electromagnetic Waves
Rojo, Marta; Munoz, Juan
2014-01-01
In this work, an educational experience is described in which a microwave communication link is used to make students aware that all electromagnetic waves have the same physical nature and properties. Experimental demonstrations are linked to theoretical concepts to increase comprehension of the physical principles underlying electromagnetic…
Electromagnetic resonance waves
International Nuclear Information System (INIS)
Villaba, J.M.; Manjon, F.J.; Guirao, A.; Andres, M.V.
1994-01-01
We describe in this paper a set of experiments designed to make qualitative and quantitative measurements on electromagnetic resonances of several simple systems. The experiments are designed for the undergraduate laboratory of Electricity and Magnetism in Physics. These experiments can help the students understanding the concept of resonance, which appears in different fields of Physics. (Author) 8 refs
The classic: Bone morphogenetic protein.
Urist, Marshall R; Strates, Basil S
2009-12-01
This Classic Article is a reprint of the original work by Marshall R. Urist and Basil S. Strates, Bone Morphogenetic Protein. An accompanying biographical sketch of Marshall R. Urist, MD is available at DOI 10.1007/s11999-009-1067-4; a second Classic Article is available at DOI 10.1007/s11999-009-1069-2; and a third Classic Article is available at DOI 10.1007/s11999-009-1070-9. The Classic Article is copyright 1971 by Sage Publications Inc. Journals and is reprinted with permission from Urist MR, Strates BS. Bone morphogenetic protein. J Dent Res. 1971;50:1392-1406.
Innovation: the classic traps.
Kanter, Rosabeth Moss
2006-11-01
Never a fad, but always in or out of fashion, innovation gets rediscovered as a growth enabler every half dozen years. Too often, though, grand declarations about innovation are followed by mediocre execution that produces anemic results, and innovation groups are quietly disbanded in cost-cutting drives. Each managerial generation embarks on the same enthusiastic quest for the next new thing. And each generation faces the same vexing challenges- most of which stem from the tensions between protecting existing revenue streams critical to current success and supporting new concepts that may be crucial to future success. In this article, Harvard Business School professor Rosabeth Moss Kanter reflects on the four major waves of innovation enthusiasm she's observed over the past 25 years. She describes the classic mistakes companies make in innovation strategy, process, structure, and skills assessment, illustrating her points with a plethora of real-world examples--including AT&T Worldnet, Timberland, and Ocean Spray. A typical strategic blunder is when managers set their hurdles too high or limit the scope of their innovation efforts. Quaker Oats, for instance, was so busy in the 1990s making minor tweaks to its product formulas that it missed larger opportunities in distribution. A common process mistake is when managers strangle innovation efforts with the same rigid planning, budgeting, and reviewing approaches they use in their existing businesses--thereby discouraging people from adapting as circumstances warrant. Companies must be careful how they structure fledgling entities alongside existing ones, Kanter says, to avoid a clash of cultures and agendas--which Arrow Electronics experienced in its attempts to create an online venture. Finally, companies commonly undervalue and underinvest in the human side of innovation--for instance, promoting individuals out of innovation teams long before their efforts can pay off. Kanter offers practical advice for avoiding
2007-01-01
M51, whose name comes from being the 51st entry in Charles Messier's catalog, is considered to be one of the classic examples of a spiral galaxy. At a distance of about 30 million light-years from Earth, it is also one of the brightest spirals in the night sky. A composite image of M51, also known as the Whirlpool Galaxy, shows the majesty of its structure in a dramatic new way through several of NASA's orbiting observatories. X-ray data from NASA's Chandra X-ray Observatory reveals point-like sources (purple) that are black holes and neutron stars in binary star systems. Chandra also detects a diffuse glow of hot gas that permeates the space between the stars. Optical data from the Hubble Space Telescope (green) and infrared emission from the Spitzer Space Telescope (red) both highlight long lanes in the spiral arms that consist of stars and gas laced with dust. A view of M51 with the Galaxy Evolution Explorer telescope shows hot, young stars that produce lots of ultraviolet energy (blue). The textbook spiral structure is thought be the result of an interaction M51 is experiencing with its close galactic neighbor, NGC 5195, which is seen just above. Some simulations suggest M51's sharp spiral shape was partially caused when NGC 5195 passed through its main disk about 500 million years ago. This gravitational tug of war may also have triggered an increased level of star formation in M51. The companion galaxy's pull would be inducing extra starbirth by compressing gas, jump-starting the process by which stars form.
Calculating hadronic properties in strong QCD
International Nuclear Information System (INIS)
Pennington, M.R.
1996-01-01
This talk gives a brief review of the progress that has been made in calculating the properties of hadrons in strong QCD. In keeping with this meeting I will concentrate on those properties that can be studied with electromagnetic probes. Though perturbative QCD is highly successful, it only applies in a limited kinematic regime, where hard scattering occur, and the quarks move in the interaction region as if they are free, pointlike objects. However, the bulk of strong interactions are governed by the long distance regime, where the strong interaction is strong. It is this regime of length scales of the order of a Fermi, that determines the spectrum of light hadrons and their properties. The calculation of these properties requires an understanding of non-perturbative QCD, of confinement and chiral symmetry breaking. (author)
Gauge theory of weak, electromagnetic and dual electromagnetic interactions
International Nuclear Information System (INIS)
Soln, J.
1980-01-01
An SU 2 x U 1 algebra, in addition to the ordinary electric charge, also establishes the existence of the dual electric charge. This is taken as an indication of the existence of dual electromagnetic interactions in nature. Here, the unification of weak, electromagnetic and dual electromagnetic interactions is performed. The Yang-Mills-type group which contains the electromagnetic, dual electromagnetic and weak currents is SUsub(L,2) x U 1 x U' 1 . The masses of vector mesons are generated through the Higgs-Kibble mechanism. A simple consistency requirement suggests that dual electromagnetism and ordinary electromagnetism have the same strengths, leading the theory to a rather good agreement with experiments. (author)
Wave propagation in electromagnetic media
International Nuclear Information System (INIS)
Davis, J.L.
1990-01-01
This book is concerned with wave propagation in reacting media, specifically in electromagnetic materials. An account is presented of the mathematical methods of wave phenomena in electromagnetic materials. The author presents the theory of time-varying electromagnetic fields, which involves a discussion of Faraday's laws, Maxwell's equations and their application to electromagnetic wave propagation under a variety of conditions. The author gives a discussion of magnetohydrodynamics and plasma physics. Chapters are included on quantum mechanics and the theory of relativity. The mathematical foundation of electromagnetic waves vis a vis partial differential equations is discussed
The classical equations of motion for a spinning point particle with charge and magnetic moment
International Nuclear Information System (INIS)
Rowe, E.G.P.; Rowe, G.T.
1987-01-01
The classical, special relativistic equations of motion are derived for a spinning point particle interacting with the electromagnetic field through its charge and magnetic moment. Radiation reaction is included. The energy tensors for the particle and for the field are developed as well-defined distributions; consequently no infinities appear. The magnitude of spin and the rest mass are conserved. (orig.)
A superfield generalization of the classical action-at-a-distance theory
International Nuclear Information System (INIS)
Tugai, V.V.; Zheltukhin, A.A.
1994-07-01
A generalization of the Fokker-Schwarzschild-Tetrode-Wheeler-Feynman electromagnetic theory onto the superspace is considered. The classical vector and spinor fields belonging to the Maxwell supermultiplet are built of the world-line coordinates of the charged particles in superspace. (author). 9 refs
Classical-limit S-matrix for heavy ion scattering
International Nuclear Information System (INIS)
Donangelo, R.J.
1977-01-01
An integral representation for the classical limit of the quantum mechanical S-matrix is developed and applied to heavy-ion Coulomb excitation and Coulomb-nuclear interference. The method combines the quantum principle of superposition with exact classical dynamics to describe the projectile-target system. A detailed consideration of the classical trajectories and of the dimensionless parameters that characterize the system is carried out. The results are compared, where possible, to exact quantum mechanical calculations and to conventional semiclassical calculations. It is found that in the case of backscattering the classical limit S-matrix method is able to almost exactly reproduce the quantum-mechanical S-matrix elements, and therefore the transition probabilities, even for projectiles as light as protons. The results also suggest that this approach should be a better approximation for heavy-ion multiple Coulomb excitation than earlier semiclassical methods, due to a more accurate description of the classical orbits in the electromagnetic field of the target nucleus. Calculations using this method indicate that the rotational excitation probabilities in the Coulomb-nuclear interference region should be very sensitive to the details of the potential at the surface of the nucleus, suggesting that heavy-ion rotational excitation could constitute a sensitive probe of the nuclear potential in this region. The application to other problems as well as the present limits of applicability of the formalism are also discussed
Classic romance in electronic arrangement
Directory of Open Access Journals (Sweden)
Kizin M.M.
2017-03-01
Full Text Available this article analyses the transformation of the performing arts of classical romance in the terms of electronic sound and performance via electronic sounds arrangements. The author focuses on the problem of synthesis of electronic sound arrangements and classical romance, offering to acquire the skills of the creative process in constantly changing conditions of live performances.
Classical higher-order processes
DEFF Research Database (Denmark)
Montesi, Fabrizio
2017-01-01
Classical Processes (CP) is a calculus where the proof theory of classical linear logic types processes à la Π-calculus, building on a Curry-Howard correspondence between session types and linear propositions. We contribute to this research line by extending CP with process mobility, inspired by ...
COMPETITION: CLASSICAL VERSUS NEOCLASSICAL VIEW
Mihaela Cornelia Sandu
2013-01-01
Competition is an important element from economical theory. Over time it has experienced several definitions and classifications much of them being contradictory. In this paper I will make a parallel between classical and neoclassical point of view according to competition. Keywords. Competition; neoclassical theory; classical theory; monopolistic; perfect competition.
Sum rules in classical scattering
International Nuclear Information System (INIS)
Bolle, D.; Osborn, T.A.
1981-01-01
This paper derives sum rules associated with the classical scattering of two particles. These sum rules are the analogs of Levinson's theorem in quantum mechanics which provides a relationship between the number of bound-state wavefunctions and the energy integral of the time delay of the scattering process. The associated classical relation is an identity involving classical time delay and an integral over the classical bound-state density. We show that equalities between the Nth-order energy moment of the classical time delay and the Nth-order energy moment of the classical bound-state density hold in both a local and a global form. Local sum rules involve the time delay defined on a finite but otherwise arbitrary coordinate space volume S and the bound-state density associated with this same region. Global sum rules are those that obtain when S is the whole coordinate space. Both the local and global sum rules are derived for potentials of arbitrary shape and for scattering in any space dimension. Finally the set of classical sum rules, together with the known quantum mechanical analogs, are shown to provide a unified method of obtaining the high-temperature expansion of the classical, respectively the quantum-mechanical, virial coefficients
'Leonard pairs' in classical mechanics
International Nuclear Information System (INIS)
Zhedanov, Alexei; Korovnichenko, Alyona
2002-01-01
Leonard pairs (LP) are matrices with the property of mutual tri-diagonality. We introduce and study a classical analogue of LP. We show that corresponding classical 'Leonard' dynamical variables satisfy non-linear relations of the AW-type with respect to Poisson brackets. (author)
Quantum mechanics from classical statistics
International Nuclear Information System (INIS)
Wetterich, C.
2010-01-01
Quantum mechanics can emerge from classical statistics. A typical quantum system describes an isolated subsystem of a classical statistical ensemble with infinitely many classical states. The state of this subsystem can be characterized by only a few probabilistic observables. Their expectation values define a density matrix if they obey a 'purity constraint'. Then all the usual laws of quantum mechanics follow, including Heisenberg's uncertainty relation, entanglement and a violation of Bell's inequalities. No concepts beyond classical statistics are needed for quantum physics - the differences are only apparent and result from the particularities of those classical statistical systems which admit a quantum mechanical description. Born's rule for quantum mechanical probabilities follows from the probability concept for a classical statistical ensemble. In particular, we show how the non-commuting properties of quantum operators are associated to the use of conditional probabilities within the classical system, and how a unitary time evolution reflects the isolation of the subsystem. As an illustration, we discuss a classical statistical implementation of a quantum computer.
International Nuclear Information System (INIS)
L'Huillier, A.
2002-01-01
When a high-power laser focuses into a gas of atoms, the electromagnetic field becomes of the same magnitude as the Coulomb field which binds a 1s electron in a hydrogen atom. 3 highly non-linear phenomena can happen: 1) ATI (above threshold ionization): electrons initially in the ground state absorb a large number of photons, many more than the minimum number required for ionization; 2) multiple ionization: many electrons can be emitted one at a time, in a sequential process, or simultaneously in a mechanism called direct or non-sequential; and 3) high order harmonic generation (HHG): efficient photon emission in the extreme ultraviolet range, in the form of high-order harmonics of the fundamental laser field can occur. The theoretical problem consists in solving the time dependent Schroedinger equation (TDSE) that describes the interaction of a many-electron atom with a laser field. A number of methods have been proposed to solve this problem in the case of a hydrogen atom or a single-active electron atom in a strong laser field. A large effort is presently being devoted to go beyond the single-active approximation. The understanding of the physics of the interaction between atoms and strong laser fields has been provided by a very simple model called ''simple man's theory''. A unified view of HHG, ATI, and non-sequential ionization, originating from the simple man's model and the strong field approximation, expressed in terms of electrons trajectories or quantum paths is slowly emerging. (A.C.)
Classicalization of Gravitons and Goldstones
Dvali, Gia; Kehagias, Alex
2011-01-01
We establish a close parallel between classicalization of gravitons and derivatively-coupled Nambu-Goldstone-type scalars. We show, that black hole formation in high energy scattering process represents classicalization with the classicalization radius given by Schwarzschild radius of center of mass energy, and with the precursor of black hole entropy being given by number of soft quanta composing this classical configuration. Such an entropy-equivalent is defined for scalar classicalons also and is responsible for exponential suppression of their decay into small number of final particles. This parallel works in both ways. For optimists that are willing to hypothesize that gravity may indeed self-unitarize at high energies via black hole formation, it illustrates that the Goldstones may not be much different in this respect, and they classicalize essentially by similar dynamics as gravitons. In the other direction, it may serve as an useful de-mystifier of via-black-hole-unitarization process and of the role...
Classical dynamics a modern perspective
Sudarshan, Ennackal Chandy George
2016-01-01
Classical dynamics is traditionally treated as an early stage in the development of physics, a stage that has long been superseded by more ambitious theories. Here, in this book, classical dynamics is treated as a subject on its own as well as a research frontier. Incorporating insights gained over the past several decades, the essential principles of classical dynamics are presented, while demonstrating that a number of key results originally considered only in the context of quantum theory and particle physics, have their foundations in classical dynamics.Graduate students in physics and practicing physicists will welcome the present approach to classical dynamics that encompasses systems of particles, free and interacting fields, and coupled systems. Lie groups and Lie algebras are incorporated at a basic level and are used in describing space-time symmetry groups. There is an extensive discussion on constrained systems, Dirac brackets and their geometrical interpretation. The Lie-algebraic description of ...
Simultaneous classical communication and quantum key distribution using continuous variables*
Qi, Bing
2016-10-01
Presently, classical optical communication systems employing strong laser pulses and quantum key distribution (QKD) systems working at single-photon levels are very different communication modalities. Dedicated devices are commonly required to implement QKD. In this paper, we propose a scheme which allows classical communication and QKD to be implemented simultaneously using the same communication infrastructure. More specially, we propose a coherent communication scheme where both the bits for classical communication and the Gaussian distributed random numbers for QKD are encoded on the same weak coherent pulse and decoded by the same coherent receiver. Simulation results based on practical system parameters show that both deterministic classical communication with a bit error rate of 10-9 and secure key distribution could be achieved over tens of kilometers of single-mode fibers. It is conceivable that in the future coherent optical communication network, QKD will be operated in the background of classical communication at a minimal cost.
From Photons to Atoms - The Electromagnetic Nature of Matter
Funaro, Daniele
2012-01-01
Motivated by a revision of the classical equations of electromagnetism that allow for the inclusion of solitary waves in the solution space, the material collected in these notes examine the consequences of adopting the modified model in the description of atomic structures. The possibility of handling "photons" in a deterministic way opens indeed a chance for reviewing the foundations of quantum physics. Atoms and molecules are described as aggregations of nuclei and electrons joined through...
Barellini, A; Bogi, L; Licitra, G; Silvi, A M; Zari, A
2009-12-01
Air traffic control (ATC) primary radars are 'classical' radars that use echoes of radiofrequency (RF) pulses from aircraft to determine their position. High-power RF pulses radiated from radar antennas may produce high electromagnetic field levels in the surrounding area. Measurement of electromagnetic fields produced by RF-pulsed radar by means of a swept-tuned spectrum analyser are investigated here. Measurements have been carried out both in the laboratory and in situ on signals generated by an ATC primary radar.
Testing strong interaction theories
International Nuclear Information System (INIS)
Ellis, J.
1979-01-01
The author discusses possible tests of the current theories of the strong interaction, in particular, quantum chromodynamics. High energy e + e - interactions should provide an excellent means of studying the strong force. (W.D.L.)
Electrophoresis in strong electric fields.
Barany, Sandor
2009-01-01
Two kinds of non-linear electrophoresis (ef) that can be detected in strong electric fields (several hundred V/cm) are considered. The first ("classical" non-linear ef) is due to the interaction of the outer field with field-induced ionic charges in the electric double layer (EDL) under conditions, when field-induced variations of electrolyte concentration remain to be small comparatively to its equilibrium value. According to the Shilov theory, the non-linear component of the electrophoretic velocity for dielectric particles is proportional to the cubic power of the applied field strength (cubic electrophoresis) and to the second power of the particles radius; it is independent of the zeta-potential but is determined by the surface conductivity of particles. The second one, the so-called "superfast electrophoresis" is connected with the interaction of a strong outer field with a secondary diffuse layer of counterions (space charge) that is induced outside the primary (classical) diffuse EDL by the external field itself because of concentration polarization. The Dukhin-Mishchuk theory of "superfast electrophoresis" predicts quadratic dependence of the electrophoretic velocity of unipolar (ionically or electronically) conducting particles on the external field gradient and linear dependence on the particle's size in strong electric fields. These are in sharp contrast to the laws of classical electrophoresis (no dependence of V(ef) on the particle's size and linear dependence on the electric field gradient). A new method to measure the ef velocity of particles in strong electric fields is developed that is based on separation of the effects of sedimentation and electrophoresis using videoimaging and a new flowcell and use of short electric pulses. To test the "classical" non-linear electrophoresis, we have measured the ef velocity of non-conducting polystyrene, aluminium-oxide and (semiconductor) graphite particles as well as Saccharomice cerevisiae yeast cells as a
Electromagnetic wave energy converter
Bailey, R. L. (Inventor)
1973-01-01
Electromagnetic wave energy is converted into electric power with an array of mutually insulated electromagnetic wave absorber elements each responsive to an electric field component of the wave as it impinges thereon. Each element includes a portion tapered in the direction of wave propagation to provide a relatively wideband response spectrum. Each element includes an output for deriving a voltage replica of the electric field variations intercepted by it. Adjacent elements are positioned relative to each other so that an electric field subsists between adjacent elements in response to the impinging wave. The electric field results in a voltage difference between adjacent elements that is fed to a rectifier to derive dc output power.
Electromagnetic fields and waves
Iskander, Magdy F
2013-01-01
The latest edition of Electromagnetic Fields and Waves retains an authoritative, balanced approach, in-depth coverage, extensive analysis, and use of computational techniques to provide a complete understanding of electromagnetic—important to all electrical engineering students. An essential feature of this innovative text is the early introduction of Maxwell's equations, together with the quantifying experimental observations made by the pioneers who discovered electromagnetics. This approach directly links the mathematical relations in Maxwell's equations to real experiments and facilitates a fundamental understanding of wave propagation and use in modern practical applications, especially in today's wireless world. New and expanded topics include the conceptual relationship between Coulomb's law and Gauss's law for calculating electric fields, the relationship between Biot-Savart's and Ampere's laws and their use in calculating magnetic fields from current sources, the development of Faraday's law from e...
Classical-quantum correspondence in electron-positron pair creation
International Nuclear Information System (INIS)
Chott, N. I.; Su, Q.; Grobe, R.
2007-01-01
We examine the creation of electron-positron pairs in a very strong force field. Using numerical solutions to quantum field theory we calculate the spatial and momentum probability distributions for the created particles. A comparison with classical mechanical phase space calculations suggests that despite the fully relativistic and quantum mechanical nature of the matter creation process, most aspects can be reproduced accurately in terms of classical mechanics
International Nuclear Information System (INIS)
Tagirov, Eh.A.
1985-01-01
A model of resonance parametric transformation of a gravitational wave to electromagnetic one is considered. Two plane monochromatic waves: a strong electromagnetic and weak gravitational - interacting in a medium generate at difference and sum frequencies an electromagnetic wave in a direction determined with the condition of spatial wave synchronism. Rarefied cold gas or beam of elementary emitters (''molecules'') serve as a medium model. Coefficients of parametric transformation have been determined
Nanofocusing of electromagnetic radiation
DEFF Research Database (Denmark)
Gramotnev, D. K.; Bozhevolnyi, Sergey I.
2014-01-01
Nanofocusing of electromagnetic radiation, that is, reducing the cross sections of propagating optical modes far beyond the diffraction limit in dielectric media, can be achieved in tapered metal-dielectric waveguides that support surface plasmon-polariton modes. Although the main principles...... radiation on the nanoscale. Here, we present the underlying physical principles of radiation nanofocusing in metallic nanostructures, overview recent progress and major developments, and consider future directions and potential applications of this subfield of nano-optics....
Electromagnetic Hammer for Metalworking
Anderson, S. A.; Brunet, F.; Dowd, A.; Durham, R.; Ezell, J.; Gorr, G.; Hartley, D.; Jackson, F.; Marchand, J.; Macfarlane, W.;
1986-01-01
High eddy currents apply pressure for cold-forming. Coil housing constructed for mechanical strength to hold coil against magnetic force, to maintain electrical contact with coil ends, and to maintain insulation between coil turns. Drilled holes placed to facilitate release of bubbles during potting. In contrast with mechanical hammers, electromagnetic hammer requires no dynamic material contact with workpiece; consequently, produces almost no change in metal grain structure.
Electromagnetic compatibility and earths
International Nuclear Information System (INIS)
Duque Henao, Alan; Casas Ospina, Favio
2001-01-01
It is such the increment of applications of electric and electronic equipment in the modern companies that the lack of control of the electromagnetic perturbations, brings, get big losses and difficulties in the normal operations. The paper contribute to ago with base in the challenges that day-by-day are confronting, where the settings to earth, to be the foundation of the electric building, are fundamental for a good coexistence among the different equipment s
Hard Electromagnetic Processes
International Nuclear Information System (INIS)
Richard, F.
1987-09-01
Among hard electromagnetic processes, I will use the most recent data and focus on quantitative test of QCD. More specifically, I will retain two items: - hadroproduction of direct photons, - Drell-Yan. In addition, I will briefly discuss a recent analysis of ISR data obtained with AFS (Axial Field Spectrometer) which sheds a new light on the e/π puzzle at low P T
Introduction to electromagnetic theory
Owen, George E
2003-01-01
A direct, stimulating approach to electromagnetic theory, this text employs matrices and matrix methods for the simple development of broad theorems. The author uses vector representation throughout the book, with numerous applications of Poisson's equation and the Laplace equation (the latter occurring in both electronics and magnetic media). Contents include the electrostatics of point charges, distributions of charge, conductors and dielectrics, currents and circuits, and the Lorentz force and the magnetic field. Additional topics comprise the magnetic field of steady currents, induced ele
Electromagnetism and interconnections
Charruau, S
2009-01-01
This book covers the theoretical problems of modeling electrical behavior of the interconnections encountered in everyday electronic products. The coverage shows the theoretical tools of waveform prediction at work in the design of a complex and high-speed digital electronic system. Scientists, research engineers, and postgraduate students interested in electromagnetism, microwave theory, electrical engineering, or the development of simulation tools software for high speed electronic system design automation will find this book an illuminating resource.
Classical optics in generalized Maxwell Chern-Simons theory
International Nuclear Information System (INIS)
Burgess, M.; Leinaas, J.M.; Loevvik, O.M.
1993-03-01
The authors consider the propagation of electromagnetic waves in a two-dimensional polarizable medium endowed with Chern-Simons terms. The dispersion relation (refractive index) of the waves is computed and the existence of linear birefringence and anomalous dispersion is shown. When absorption is taken into account, the classic signature of a Voigt effect is found. In the case where linearly-polarized, three-dimensional waves pass through a two-dimensional plane, it is shown that there is optical activity, and the analogue of Verdet's constant is computed. 19 refs., 2 figs
A theory of strong interactions ''from'' general relativity
International Nuclear Information System (INIS)
Caldirola, P.; Recami, E.
1979-01-01
In this paper a previous letter (where, among other things, a classical ''quark confinement'' was derived from general relativity plus dilatation-covariance), is completed by showing that the theory is compatible also with quarks ''asymptotic freedom''. Then -within a bi-scale theory of gravitational and strong interactions- a classical field theory is proposed for the (strong) interactions between hadrons. Various consequences are briefly analysed
Classical and quantum mechanics of non-abelian gauge fields
International Nuclear Information System (INIS)
Savvidy, G.K.
1984-01-01
Classical and quantum mechanics of non-abelian gauge fields are investigated both with and without spontaneous symmetry breaking. The fundamental subsystem (FS) of Yang-Mills classical mechanics (YMCM) is considered. It is shown to be a Kolmogorov K-system, and hence to have strong statistical properties. Integrable systems are also found, to which in terms of KAM theory Yang-Mills-Higgs classical mechanics (YMHCM) is close. Quantum-mechanical properties of the YM system and their relation to the problem of confinement are discussed. (orig.)
Electromagnetic radiation unmasked
International Nuclear Information System (INIS)
Hart, P.
1996-01-01
This article describes the nature of the electromagnetic waves, what they are and how do they affect us. Current concern is focused on exposure to low level power-frequency magnetic fields like microwave radiation from mobile phones and leaking microwave ovens; high power radiation from defence and airport radars; fields close to high voltage transmission lines; radio frequency fields from industrial welders and heaters and DC magnetic fields in aluminium smelters. These fields with frequency less than 300 GHz do not carry sufficient energy to break chemical bonds and it is assumed that they cannot damage cell DNA. The amount of radiation absorbed by a human exposed to far field electromagnetic radiation (EMR) depends on the orientation and size of the person. In the 30-300 MHz range it is possible to excite resonance in the whole or partial body such as the head. It is emphasised that since there are some evidence that electromagnetic fields do harm, a policy of prudent avoidance is recommended, especially for children. ills
The electromagnetic dark sector
International Nuclear Information System (INIS)
Jimenez, Jose Beltran; Maroto, Antonio L.
2010-01-01
We consider electromagnetic field quantization in an expanding universe. We find that the covariant (Gupta-Bleuler) method exhibits certain difficulties when trying to impose the quantum Lorenz condition on cosmological scales. We thus explore the possibility of consistently quantizing without imposing such a condition. In this case there are three physical states, which are the two transverse polarizations of the massless photon and a new massless scalar mode coming from the temporal and longitudinal components of the electromagnetic field. An explicit example in de Sitter space-time shows that it is still possible to eliminate the negative norm state and to ensure the positivity of the energy in this theory. The new state is decoupled from the conserved electromagnetic currents, but is non-conformally coupled to gravity and therefore can be excited from vacuum fluctuations by the expanding background. The cosmological evolution ensures that the new state modifies Maxwell's equations in a totally negligible way on sub-Hubble scales. However, on cosmological scales it can give rise to a non-negligible energy density which could explain in a natural way the present phase of accelerated expansion of the universe.
Design and analysis of an electromagnetic turnout for the superconducting Maglev system
International Nuclear Information System (INIS)
Li, Y.J.; Dai, Q.; Zhang, Y.; Wang, H.; Chen, Z.; Sun, R.X.; Zheng, J.; Deng, C.Y.; Deng, Z.G.
2016-01-01
Highlights: • The switching principle of electromagnetic turnout for a Halbach-type magnetic rail was presented. • Shape design and optimization of the electromagnet for electromagnetic turnout were conducted. • Magnetic field distribution over the working area of electromagnetic turnout was analyzed. • Feasibility of the electromagnetic turnout was proved. - Abstract: Turnout is a crucial track junction device of the ground rail transportation system. For high temperature superconducting (HTS) Maglev system, the permanent magnet guideway (PMG) makes the strong magnetic force existing between rail segments, which may cause moving difficulties and increase the operation cost when switching a PMG. In this paper, a non-mechanical ‘Y’ shaped Halbach-type electromagnetic turnout was proposed. By replacing the PMs with electromagnets, the turnout can guide the maglev vehicle running into another PMG by simply controlling the current direction of electromagnets. The material and structure parameters of the electromagnets were optimized by simulation. The results show that the optimized electromagnet can keep the magnetic field above it as strong as the PMs’, meanwhile feasible for design and manufacture. This work provides valuable references for the future design in non-mechanical PMG turnout.
Design and analysis of an electromagnetic turnout for the superconducting Maglev system
Energy Technology Data Exchange (ETDEWEB)
Li, Y.J. [Applied Superconductivity Laboratory, State Key Laboratory of Traction Power, Southwest Jiaotong University, Chengdu 610031 (China); School of Information Science and Technology, Southwest Jiaotong University, Chengdu 610031 (China); Dai, Q. [School of Information Science and Technology, Southwest Jiaotong University, Chengdu 610031 (China); Zhang, Y. [Applied Superconductivity Laboratory, State Key Laboratory of Traction Power, Southwest Jiaotong University, Chengdu 610031 (China); Wang, H.; Chen, Z. [School of Mechanical Engineering, Southwest Jiaotong University, Chengdu 610031 (China); Sun, R.X.; Zheng, J. [Applied Superconductivity Laboratory, State Key Laboratory of Traction Power, Southwest Jiaotong University, Chengdu 610031 (China); Deng, C.Y. [Applied Superconductivity Laboratory, State Key Laboratory of Traction Power, Southwest Jiaotong University, Chengdu 610031 (China); School of Information Science and Technology, Southwest Jiaotong University, Chengdu 610031 (China); Deng, Z.G., E-mail: deng@swjtu.cn [Applied Superconductivity Laboratory, State Key Laboratory of Traction Power, Southwest Jiaotong University, Chengdu 610031 (China)
2016-09-15
Highlights: • The switching principle of electromagnetic turnout for a Halbach-type magnetic rail was presented. • Shape design and optimization of the electromagnet for electromagnetic turnout were conducted. • Magnetic field distribution over the working area of electromagnetic turnout was analyzed. • Feasibility of the electromagnetic turnout was proved. - Abstract: Turnout is a crucial track junction device of the ground rail transportation system. For high temperature superconducting (HTS) Maglev system, the permanent magnet guideway (PMG) makes the strong magnetic force existing between rail segments, which may cause moving difficulties and increase the operation cost when switching a PMG. In this paper, a non-mechanical ‘Y’ shaped Halbach-type electromagnetic turnout was proposed. By replacing the PMs with electromagnets, the turnout can guide the maglev vehicle running into another PMG by simply controlling the current direction of electromagnets. The material and structure parameters of the electromagnets were optimized by simulation. The results show that the optimized electromagnet can keep the magnetic field above it as strong as the PMs’, meanwhile feasible for design and manufacture. This work provides valuable references for the future design in non-mechanical PMG turnout.
Quantum-classical correspondence for the Fourier spectrum of a trajectory
International Nuclear Information System (INIS)
Heller, E.J.
1983-01-01
Using a displaced localized wavepacket (coherent state) as a quantum analog to a classical trajectory, we examine the Fourier spectrum of the expectation value of position Xsub(t)sup(Q), and compare it with the classical Fourier spectrum of position Xsub(t). In both the quasiperiodic and chaotic regimes, a strong classical-quantum correspondence exists in the Fourier spectrum. However, the quantum spectrum has certain interesting features not present in the classical case. (orig.)
A classical-quantum coupling strategy for a hierarchy of one dimensional models for semiconductors
Jourdana, Clément; Pietra, Paola; Vauchelet, Nicolas
2014-01-01
We consider one dimensional coupled classical-quantum models for quantum semiconductor device simulations. The coupling occurs in the space variable : the domain of the device is divided into a region with strong quantum effects (quantum zone) and a region where quantum effects are negligible (classical zone). In the classical zone, transport in diffusive approximation is modeled through diffusive limits of the Boltzmann transport equation. This leads to a hierarchy of classical model. The qu...
Loire Classics: Reviving Classicism in some Loire Poets
Directory of Open Access Journals (Sweden)
Wim Verbaal
2017-06-01
Full Text Available The term 'Loire poets' has come to refer to a rather undefinable group of poets that in the second half of the eleventh century distinguishes itself through its refined poetics. They are often characterized as medieval humanists thanks to their renewed interest in the classics. Sometimes their movement is labelled a 'classicist' one. But what does this 'classicism' mean? Is it even permitted to speak of medieval 'classicisms'? This contribution approaches the question of whether we can apply this modern label to pre-modern phenomena. Moreover, it explores the changes in attitude towards the classics that sets the Loire poets off from their predecessors and contemporaries. The article focuses on poems by Hildebert of Lavardin, Baudri of Bourgueil, Marbod of Rennes, and Geoffrey of Reims. They are compared with some contemporary poets, such as Reginald of Canterbury and Sigebert of Gembloux.
Biophysical mechanisms complementing "classical" cell biology.
Funk, Richard H W
2018-01-01
This overview addresses phenomena in cell- and molecular biology which are puzzling by their fast and highly coordinated way of organization. Generally, it appears that informative processes probably involved are more on the biophysical than on the classical biochemical side. The coordination problem is explained within the first part of the review by the topic of endogenous electrical phenomena. These are found e.g. in fast tissue organization and reorganization processes like development, wound healing and regeneration. Here, coupling into classical biochemical signaling and reactions can be shown by modern microscopy, electronics and bioinformatics. Further, one can follow the triggered reactions seamlessly via molecular biology till into genetics. Direct observation of intracellular electric processes is very difficult because of e.g. shielding through the cell membrane and damping by other structures. Therefore, we have to rely on photonic and photon - phonon coupling phenomena like molecular vibrations, which are addressed within the second part. Molecules normally possess different charge moieties and thus small electromagnetic (EMF) patterns arise during molecular vibration. These patterns can now be measured best within the optical part of the spectrum - much less in the lower terahertz till kHz and lower Hz part (third part of this review). Finally, EMFs facilitate quantum informative processes in coherent domains of molecular, charge and electron spin motion. This helps to coordinate such manifold and intertwined processes going on within cells, tissues and organs (part 4). Because the phenomena described in part 3 and 4 of the review still await really hard proofs we need concerted efforts and a combination of biophysics, molecular biology and informatics to unravel the described mysteries in "physics of life".
Resonant emission of electromagnetic waves by plasma solitons
International Nuclear Information System (INIS)
Mironov, V.A.; Sergeev, A.M.; Khimich, A.V.
1988-01-01
The ability of plasma-wave solitons to radiate electromagnetic waves at the frequency of the natural oscillations of the field is considered. It is shown that this radiation is the main energy dissipation channel for strong plasma turbulence in a magnetoactive plasma. An interpretation is proposed for the artificial radio emission produced when the ionosphere is acted upon by beams of strong electromagnetic waves. The use of this phenomenon for plasma turbulence, particularly in the outer-space plasma near the earth, is discussed
Subwavelength resonant antennas enhancing electromagnetic energy harvesting
Oumbe Tekam, Gabin; Ginis, Vincent; Seetharamdoo, Divitha; Danckaert, Jan
2016-04-01
In this work, an electromagnetic energy harvester operating at microwave frequencies is designed based on a cut- wire metasurface. This metamaterial is known to contain a quasistatic electric dipole resonator leading to a strong resonant electric response when illuminated by electromagnetic fields.1 Starting from an equivalent electrical circuit, we analytically design the parameters of the system to tune the resonance frequency of the harvester at the desired frequency band. Subsequently, we compare these results with numerical simulations, which have been obtained using finite elements numerical simulations. Finally, we optimize the design by investigating the best arrangement for energy harvesting by coupling in parallel and in series many single layers of cut-wire metasurfaces. We also discuss the implementation of different geometries and sizes of the cut-wire metasurface for achieving different center frequencies and bandwidths.
Pulse generation scheme for flying electromagnetic doughnuts
Papasimakis, Nikitas; Raybould, Tim; Fedotov, Vassili A.; Tsai, Din Ping; Youngs, Ian; Zheludev, Nikolay I.
2018-05-01
Transverse electromagnetic plane waves are fundamental solutions of Maxwells equations. It is less known that a radically different type of solutions has been described theoretically, but has never been realized experimentally, that exist only in the form of short bursts of electromagnetic energy propagating in free space at the speed of light. They are distinguished from transverse waves by a doughnutlike configuration of electric and magnetic fields with a strong field component along the propagation direction. Here, we demonstrate numerically that such flying doughnuts can be generated from conventional pulses using a singular metamaterial converter designed to manipulate both the spatial and spectral structure of the input pulse. The ability to generate flying doughnuts is of fundamental interest, as they shall interact with matter in unique ways, including nontrivial field transformations upon reflection from interfaces and the excitation of toroidal response and anapole modes in matter, hence offering opportunities for telecommunications, sensing, and spectroscopy.
Electromagnetic Compatibility in Railways Analysis and Management
Ogunsola, Ade
2013-01-01
A railway is a complex distributed engineering system: the construction of a new railway or the modernisation of a existing one requires a deep understanding of the constitutive components and their interaction, inside the system itself and towards the outside world. The former covers the various subsystems (featuring a complex mix of high power sources, sensitive safety critical systems, intentional transmitters, etc.) and their interaction, including the specific functions and their relevance to safety. The latter represents all the additional possible external victims and sources of electromagnetic interaction. EMC thus starts from a comprehension of the emissions and immunity characteristics and the interactions between sources and victims, with a strong relationship to electromagnetics and to system modeling. On the other hand, the said functions are achieved and preserved and their relevance for safety is adequately handled, if the related requirements are well posed and managed throughout the process f...
Coherent hybrid electromagnetic field imaging
Cooke, Bradly J [Jemez Springs, NM; Guenther, David C [Los Alamos, NM
2008-08-26
An apparatus and corresponding method for coherent hybrid electromagnetic field imaging of a target, where an energy source is used to generate a propagating electromagnetic beam, an electromagnetic beam splitting means to split the beam into two or more coherently matched beams of about equal amplitude, and where the spatial and temporal self-coherence between each two or more coherently matched beams is preserved. Two or more differential modulation means are employed to modulate each two or more coherently matched beams with a time-varying polarization, frequency, phase, and amplitude signal. An electromagnetic beam combining means is used to coherently combine said two or more coherently matched beams into a coherent electromagnetic beam. One or more electromagnetic beam controlling means are used for collimating, guiding, or focusing the coherent electromagnetic beam. One or more apertures are used for transmitting and receiving the coherent electromagnetic beam to and from the target. A receiver is used that is capable of square-law detection of the coherent electromagnetic beam. A waveform generator is used that is capable of generation and control of time-varying polarization, frequency, phase, or amplitude modulation waveforms and sequences. A means of synchronizing time varying waveform is used between the energy source and the receiver. Finally, a means of displaying the images created by the interaction of the coherent electromagnetic beam with target is employed.
Electromagnetic force on a brane
International Nuclear Information System (INIS)
Li, Li-Xin
2016-01-01
A fundamental assumption in the theory of brane world is that all matter and radiation are confined on the four-dimensional brane and only gravitons can propagate in the five-dimensional bulk spacetime. The brane world theory did not provide an explanation for the existence of electromagnetic fields and the origin of the electromagnetic field equation. In this paper, we propose a model for explaining the existence of electromagnetic fields on a brane and deriving the electromagnetic field equation. Similar to the case in Kaluza–Klein theory, we find that electromagnetic fields and the electromagnetic field equation can be derived from the five-dimensional Einstein field equation. However, the derived electromagnetic field equation differs from the Maxwell equation by containing a term with the electromagnetic potential vector coupled to the spacetime curvature tensor. So it can be considered as generalization of the Maxwell equation in a curved spacetime. The gravitational field equation on the brane is also derived with the stress–energy tensor for electromagnetic fields explicitly included and the Weyl tensor term explicitly expressed with matter fields and their derivatives in the direction of the extra-dimension. The model proposed in the paper can be regarded as unification of electromagnetic and gravitational interactions in the framework of brane world theory. (paper)
Quantum Computing's Classical Problem, Classical Computing's Quantum Problem
Van Meter, Rodney
2013-01-01
Tasked with the challenge to build better and better computers, quantum computing and classical computing face the same conundrum: the success of classical computing systems. Small quantum computing systems have been demonstrated, and intermediate-scale systems are on the horizon, capable of calculating numeric results or simulating physical systems far beyond what humans can do by hand. However, to be commercially viable, they must surpass what our wildly successful, highly advanced classica...
The Wigner representation of classical mechanics, quantization and classical limit
International Nuclear Information System (INIS)
Bolivar, A.O.
2001-08-01
Starting from the Liouvillian formulation of classical physics it is possible by means of a Fourier transform to introduce the Wigner representation and to derive an operator structure to classical mechanisms. The importance of this new representation lies on the fact that it turns out to be suitable route to establish a general method of quantization directly from the equations of motion without alluding to the existence of Hamiltonian and Lagrangian functions. Following this approach we quantize only the motion of a Browian particle with non-linear friction in the Markovian approximation - the thermal bath may be quantum or classical -, thus when the bath is classically described we obtain a master equation which reduces to Caldeira-Legget equation for the linear friction case, and when the reservoir is quantum we get an equation reducing to the one found by Caldeira et al. By neglecting the environmental influence we show that the system can be approximately described by equations of motion in terms of wave function, such as the Schrodinger-Langevin equation and equations of the Caldirola-Kanai type. Finally to make the present study self-consistent we evaluate the classical limit of these dynamical equations employing a new classical limiting method h/2π → 0. (author)
The Wigner representation of classical mechanics, quantization and classical limit
Energy Technology Data Exchange (ETDEWEB)
Bolivar, A.O. [Centro Brasileiro de Pesquisas Fisicas (CBPF), Rio de Janeiro, RJ (Brazil)
2001-08-01
Starting from the Liouvillian formulation of classical physics it is possible by means of a Fourier transform to introduce the Wigner representation and to derive an operator structure to classical mechanisms. The importance of this new representation lies on the fact that it turns out to be suitable route to establish a general method of quantization directly from the equations of motion without alluding to the existence of Hamiltonian and Lagrangian functions. Following this approach we quantize only the motion of a Browian particle with non-linear friction in the Markovian approximation - the thermal bath may be quantum or classical -, thus when the bath is classically described we obtain a master equation which reduces to Caldeira-Legget equation for the linear friction case, and when the reservoir is quantum we get an equation reducing to the one found by Caldeira et al. By neglecting the environmental influence we show that the system can be approximately described by equations of motion in terms of wave function, such as the Schrodinger-Langevin equation and equations of the Caldirola-Kanai type. Finally to make the present study self-consistent we evaluate the classical limit of these dynamical equations employing a new classical limiting method h/2{pi} {yields} 0. (author)
Classicality of quantum information processing
International Nuclear Information System (INIS)
Poulin, David
2002-01-01
The ultimate goal of the classicality program is to quantify the amount of quantumness of certain processes. Here, classicality is studied for a restricted type of process: quantum information processing (QIP). Under special conditions, one can force some qubits of a quantum computer into a classical state without affecting the outcome of the computation. The minimal set of conditions is described and its structure is studied. Some implications of this formalism are the increase of noise robustness, a proof of the quantumness of mixed state quantum computing, and a step forward in understanding the very foundation of QIP
Electromagnetic processes in relativistic heavy ion collisions
International Nuclear Information System (INIS)
Bertulani, C.A.; Universidade Federal do Rio de Janeiro; Baur, G.
1987-10-01
A study of the processes generated by the electromagnetic interaction in relativistic nuclear, and atomic collisions is presented. There is nowadays a vivid interest in this field due to the construction of relativistic heavy ion accelerators. Certainly, the most important purpose of these relativistic heavy ion machines is the study of nuclear matter under extreme conditions. In central nucleus-nucleus collisions one hopes to observe new forms of nuclear matter, like the quark-gluon plasma. On the other hand, very strong electromagnetic fields for a very short time are present in distant collisions with no nuclear contact. Such fields can also lead to interesting effects, which are discussed here. There has been many interesting theoretical and experimental developments on this subject, and new areas of research were opened. Of special interest is, e.g., the case of nuclear fragmentation. This is accomplished through the excitation of giant resonances or by direct breakt-up of the nuclei by means of their electromagnetic interaction. It is shown that this process can be used to study nuclear structure properties which are not accessible by means of the traditional electromagnetic excitation at nonrelativistic energies. The creation of particles is also of interest due the large cross sections, specially in the case of electron-positron pair creation. Although to explain the many processes originated in this way one can develop very elaborate and complicated calculations, the results can be understood in very simple terms because of our almost complete comprehension of the electromagntic interaction. For those processes where the electromagntic interaction plays the dominant role this is clearly a very useful tool for the investigation of the structures created by the strong interaction in the nuclei or hadrons. (orig.)
Fast breeder reactor electromagnetic pump
International Nuclear Information System (INIS)
Araseki, Hideo; Murakami, Takahiro
2008-01-01
Main pumps circulating sodium in the FBR type reactor have been mechanical types, not electromagnetic pumps. Electromagnetic pump of 1-2 m 3 /min has been used as an auxiliary pump. Large sized electromagnetic pumps such as several hundred m 3 /min have not been commercialized due to technical difficulties with electromagnetic instability and pressure pulsations. This article explained electromagnetic and fluid equations and magnetic Reynolds number related with electromagnetic pumps and numerical analysis of instability characteristics and pressure pulsations and then described applications of the results to FBR system. Magnetic Reynolds number must be chosen less than one with appropriate operating frequency and optimum slip of 0.2-0.4. (T. Tanaka)
Classical Limit and Quantum Logic
Losada, Marcelo; Fortin, Sebastian; Holik, Federico
2018-02-01
The analysis of the classical limit of quantum mechanics usually focuses on the state of the system. The general idea is to explain the disappearance of the interference terms of quantum states appealing to the decoherence process induced by the environment. However, in these approaches it is not explained how the structure of quantum properties becomes classical. In this paper, we consider the classical limit from a different perspective. We consider the set of properties of a quantum system and we study the quantum-to-classical transition of its logical structure. The aim is to open the door to a new study based on dynamical logics, that is, logics that change over time. In particular, we appeal to the notion of hybrid logics to describe semiclassical systems. Moreover, we consider systems with many characteristic decoherence times, whose sublattices of properties become distributive at different times.
Classical Mechanics and Symplectic Integration
DEFF Research Database (Denmark)
Nordkvist, Nikolaj; Hjorth, Poul G.
2005-01-01
Content: Classical mechanics: Calculus of variations, Lagrange’s equations, Symmetries and Noether’s theorem, Hamilton’s equations, cannonical transformations, integrable systems, pertubation theory. Symplectic integration: Numerical integrators, symplectic integrators, main theorem on symplectic...
Quantum and classical ripples in graphene
Hašík, Juraj; Tosatti, Erio; MartoÅák, Roman
2018-04-01
Thermal ripples of graphene are well understood at room temperature, but their quantum counterparts at low temperatures are in need of a realistic quantitative description. Here we present atomistic path-integral Monte Carlo simulations of freestanding graphene, which show upon cooling a striking classical-quantum evolution of height and angular fluctuations. The crossover takes place at ever-decreasing temperatures for ever-increasing wavelengths so that a completely quantum regime is never attained. Zero-temperature quantum graphene is flatter and smoother than classical graphene at large scales yet rougher at short scales. The angular fluctuation distribution of the normals can be quantitatively described by coexistence of two Gaussians, one classical strongly T -dependent and one quantum about 2° wide, of zero-point character. The quantum evolution of ripple-induced height and angular spread should be observable in electron diffraction in graphene and other two-dimensional materials, such as MoS2, bilayer graphene, boron nitride, etc.
Classical theory of radiating strings
Copeland, Edmund J.; Haws, D.; Hindmarsh, M.
1990-01-01
The divergent part of the self force of a radiating string coupled to gravity, an antisymmetric tensor and a dilaton in four dimensions are calculated to first order in classical perturbation theory. While this divergence can be absorbed into a renormalization of the string tension, demanding that both it and the divergence in the energy momentum tensor vanish forces the string to have the couplings of compactified N = 1 D = 10 supergravity. In effect, supersymmetry cures the classical infinities.
Teaching Classical Mechanics using Smartphones
Chevrier, Joel; Madani, Laya; Ledenmat, Simon; Bsiesy, Ahmad
2012-01-01
Using a personal computer and a smartphone, iMecaProf is a software that provides a complete teaching environment for practicals associated to a Classical Mechanics course. iMecaProf proposes a visual, real time and interactive representation of data transmitted by a smartphone using the formalism of Classical Mechanics. Using smartphones is more than using a set of sensors. iMecaProf shows students that important concepts of physics they here learn, are necessary to control daily life smartp...
Dynamical systems in classical mechanics
Kozlov, V V
1995-01-01
This book shows that the phenomenon of integrability is related not only to Hamiltonian systems, but also to a wider variety of systems having invariant measures that often arise in nonholonomic mechanics. Each paper presents unique ideas and original approaches to various mathematical problems related to integrability, stability, and chaos in classical dynamics. Topics include… the inverse Lyapunov theorem on stability of equilibria geometrical aspects of Hamiltonian mechanics from a hydrodynamic perspective current unsolved problems in the dynamical systems approach to classical mechanics
Quantum money with classical verification
Energy Technology Data Exchange (ETDEWEB)
Gavinsky, Dmitry [NEC Laboratories America, Princeton, NJ (United States)
2014-12-04
We propose and construct a quantum money scheme that allows verification through classical communication with a bank. This is the first demonstration that a secure quantum money scheme exists that does not require quantum communication for coin verification. Our scheme is secure against adaptive adversaries - this property is not directly related to the possibility of classical verification, nevertheless none of the earlier quantum money constructions is known to possess it.
Quantum money with classical verification
International Nuclear Information System (INIS)
Gavinsky, Dmitry
2014-01-01
We propose and construct a quantum money scheme that allows verification through classical communication with a bank. This is the first demonstration that a secure quantum money scheme exists that does not require quantum communication for coin verification. Our scheme is secure against adaptive adversaries - this property is not directly related to the possibility of classical verification, nevertheless none of the earlier quantum money constructions is known to possess it
Quantum formalism for classical statistics
Wetterich, C.
2018-06-01
In static classical statistical systems the problem of information transport from a boundary to the bulk finds a simple description in terms of wave functions or density matrices. While the transfer matrix formalism is a type of Heisenberg picture for this problem, we develop here the associated Schrödinger picture that keeps track of the local probabilistic information. The transport of the probabilistic information between neighboring hypersurfaces obeys a linear evolution equation, and therefore the superposition principle for the possible solutions. Operators are associated to local observables, with rules for the computation of expectation values similar to quantum mechanics. We discuss how non-commutativity naturally arises in this setting. Also other features characteristic of quantum mechanics, such as complex structure, change of basis or symmetry transformations, can be found in classical statistics once formulated in terms of wave functions or density matrices. We construct for every quantum system an equivalent classical statistical system, such that time in quantum mechanics corresponds to the location of hypersurfaces in the classical probabilistic ensemble. For suitable choices of local observables in the classical statistical system one can, in principle, compute all expectation values and correlations of observables in the quantum system from the local probabilistic information of the associated classical statistical system. Realizing a static memory material as a quantum simulator for a given quantum system is not a matter of principle, but rather of practical simplicity.
Method of moments in electromagnetics
Gibson, Walton C
2007-01-01
Responding to the need for a clear, up-to-date introduction to the field, The Method of Moments in Electromagnetics explores surface integral equations in electromagnetics and presents their numerical solution using the method of moments (MOM) technique. It provides the numerical implementation aspects at a nuts-and-bolts level while discussing integral equations and electromagnetic theory at a higher level. The author covers a range of topics in this area, from the initial underpinnings of the MOM to its current applications. He first reviews the frequency-domain electromagnetic theory and t
Electromagnetic fields in biological systems
National Research Council Canada - National Science Library
Lin, James C
2012-01-01
"Focusing on exposure, induced fields, and absorbed energy, this volume covers the interaction of electromagnetic fields and waves with biological systems, spanning static fields to terahertz waves...
Electromagnetic waves in stratified media
Wait, James R; Fock, V A; Wait, J R
2013-01-01
International Series of Monographs in Electromagnetic Waves, Volume 3: Electromagnetic Waves in Stratified Media provides information pertinent to the electromagnetic waves in media whose properties differ in one particular direction. This book discusses the important feature of the waves that enables communications at global distances. Organized into 13 chapters, this volume begins with an overview of the general analysis for the electromagnetic response of a plane stratified medium comprising of any number of parallel homogeneous layers. This text then explains the reflection of electromagne
Handheld Broadband Electromagnetic UXO Sensor
National Research Council Canada - National Science Library
Won, I. J; San Filipo, William A; Marqusee, Jeffrey; Andrews, Anne; Robitaille, George; Fairbanks, Jeffrey; Overbay, Larry
2005-01-01
The broadband electromagnetic sensor improvement and demonstration undertaken in this project took the prototype GEM-3 and evolved it into an operational sensor with increased bandwidth and dynamic...
Battlefield Electromagnetic Environments Office (BEEO)
Federal Laboratory Consortium — The Battlefield Electromagnetic Environments Office (BEEO) develops, maintains, and operates the Army Materiel Command (AMC) databases for spectrum management, per...
Interaction of neutral particles with strong laser fields
Energy Technology Data Exchange (ETDEWEB)
Meuren, Sebastian; Keitel, Christoph H.; Di Piazza, Antonino [Max-Planck-Institut fuer Kernphysik, Saupfercheckweg 1, D-69117 Heidelberg (Germany)
2013-07-01
Since the invention of the laser in the 1960s the experimentally available field strengths have continuously increased. The current peak intensity record is 2 x 10{sup 22} W/cm{sup 2} and next generation facilities such as ELI, HiPER and XCELS plan to reach even intensities of the order of 10{sup 24} W/cm{sup 2}. Thus, modern laser facilities are a clean source for very strong external electromagnetic fields and promise new and interesting high-energy physics experiments. In particular, strong laser fields could be used to test non-linear effects in quantum field theory. Earlier we have investigated how radiative corrections modify the coupling of a charged particle inside a strong plane-wave electromagnetic background field. However, a charged particle couples already at tree level to electromagnetic radiation. Therefore, we have now analyzed how the coupling between neutral particles and radiation is affected by a very strong plane-wave electromagnetic background field, when loop corrections are taken into account. In particular, the case of neutrinos is discussed.
Quark imprisonment as the origin of strong interactions
Amati, Daniele
1974-01-01
A formal scheme is suggested in which the only dynamical ingredients are weak and electro-magnetic interactions with quarks and leptons treated on the same footing. Strong interactions are generated by the requirement that quarks do not appear physically. (7 refs).
Nonrelativistic Schroedinger equation in quasi-classical theory
International Nuclear Information System (INIS)
Wignall, J.W.G.
1987-01-01
The author has recently proposed a quasi-classical theory of particles and interactions in which particles are pictured as extended periodic disturbances in a universal field chi(x,t), interacting with each other via nonlinearity in the equation of motion for chi. The present paper explores the relationship of this theory to nonrelativistic quantum mechanics; as a first step, it is shown how it is possible to construct from chi a configuration-space wave function Psi(x 1 , X 2 , t), and that the theory requires that Psi satisfy the two-particle Schroedinger equation in the case where the two particles are well separated from each other. This suggests that the multiparticle Schroedinger equation can be obtained as a direct consequence of the quasi-classical theory without any use of the usual formalism (Hilbert space, quantization rules, etc.) of conventional quantum theory and in particular without using the classical canonical treatment of a system as a crutch theory which has subsequently to be quantized. The quasi-classical theory also suggests the existence of a preferred absolute gauge for the electromagnetic potentials
International Nuclear Information System (INIS)
Prykarpatsky, A.K.; Bogolubov, J.R.
2016-01-01
The classical Maxwell electromagnetic field and the Lorentz-type force equations are rederived in the framework of the Feynman proper time paradigm and the related vacuum field theory approach. The classical Ampere law origin is rederived, and its relationship with the Feynman proper time paradigm is discussed. The electron inertia problem is analyzed in detail within the Lagrangian and Hamiltonian formalisms and the related pressure-energy compensation principle of stochastic electrodynamics. The modified Abraham-Lorentz damping radiation force is derived and the electromagnetic electron mass origin is argued
Electromagnetic shielding formulae
International Nuclear Information System (INIS)
Dahlberg, E.
1979-02-01
This addendum to an earlier collection of electromagnetic shielding formulae (TRITA-EPP-75-27) contains simple transfer matrices suitable for calculating the quasistatic shielding efficiency for multiple transverse-field and axial-field cylindrical and spherical shields, as well as for estimating leakage fields from long coaxial cables and the normal-incidence transmission of a plane wave through a multiple plane shield. The differences and similarities between these cases are illustrated by means of equivalent circuits and transmission line analogies. The addendum also includes a discussion of a possible heuristic improvement of some shielding formulae. (author)
Handbook of electromagnetic compatibility
1995-01-01
This""know-how""book gives readers a concise understanding of the fundamentals of EMC, from basic mathematical and physical concepts through present, computer-age methods used in analysis, design, and tests. With contributions from leading experts in their fields, the text provides a comprehensive overview. Fortified with information on how to solve potential electromagnetic interference (EMI) problems that may arise in electronic design, practitioners will be betterable to grasp the latest techniques, trends, and applications of this increasingly important engineering discipline.Handbook of E
A scenario for inflationary magnetogenesis without strong coupling problem
Energy Technology Data Exchange (ETDEWEB)
Tasinato, Gianmassimo [Department of Physics, Swansea University,Swansea, SA2 8PP (United Kingdom); Institute of Cosmology and Gravitation, University of Portsmouth,Portsmouth, PO1 3FX (United Kingdom)
2015-03-23
Cosmological magnetic fields pervade the entire universe, from small to large scales. Since they apparently extend into the intergalactic medium, it is tantalizing to believe that they have a primordial origin, possibly being produced during inflation. However, finding consistent scenarios for inflationary magnetogenesis is a challenging theoretical problem. The requirements to avoid an excessive production of electromagnetic energy, and to avoid entering a strong coupling regime characterized by large values for the electromagnetic coupling constant, typically allow one to generate only a tiny amplitude of magnetic field during inflation. We propose a scenario for building gauge-invariant models of inflationary magnetogenesis potentially free from these issues. The idea is to derivatively couple a dynamical scalar, not necessarily the inflaton, to fermionic and electromagnetic fields during the inflationary era. Such couplings give additional freedom to control the time-dependence of the electromagnetic coupling constant during inflation. This fact allows us to find conditions to avoid the strong coupling problems that affect many of the existing models of magnetogenesis. We do not need to rely on a particular inflationary set-up for developing our scenario, that might be applied to different realizations of inflation. On the other hand, specific requirements have to be imposed on the dynamics of the scalar derivatively coupled to fermions and electromagnetism, that we are able to satisfy in an explicit realization of our proposal.
A scenario for inflationary magnetogenesis without strong coupling problem
Energy Technology Data Exchange (ETDEWEB)
Tasinato, Gianmassimo, E-mail: gianmassimo.tasinato@port.ac.uk [Department of Physics, Swansea University, Swansea, SA2 8PP U.K. (United Kingdom)
2015-03-01
Cosmological magnetic fields pervade the entire universe, from small to large scales. Since they apparently extend into the intergalactic medium, it is tantalizing to believe that they have a primordial origin, possibly being produced during inflation. However, finding consistent scenarios for inflationary magnetogenesis is a challenging theoretical problem. The requirements to avoid an excessive production of electromagnetic energy, and to avoid entering a strong coupling regime characterized by large values for the electromagnetic coupling constant, typically allow one to generate only a tiny amplitude of magnetic field during inflation. We propose a scenario for building gauge-invariant models of inflationary magnetogenesis potentially free from these issues. The idea is to derivatively couple a dynamical scalar, not necessarily the inflaton, to fermionic and electromagnetic fields during the inflationary era. Such couplings give additional freedom to control the time-dependence of the electromagnetic coupling constant during inflation. This fact allows us to find conditions to avoid the strong coupling problems that affect many of the existing models of magnetogenesis. We do not need to rely on a particular inflationary set-up for developing our scenario, that might be applied to different realizations of inflation. On the other hand, specific requirements have to be imposed on the dynamics of the scalar derivatively coupled to fermions and electromagnetism, that we are able to satisfy in an explicit realization of our proposal.
Abortion: Strong's counterexamples fail
DEFF Research Database (Denmark)
Di Nucci, Ezio
2009-01-01
This paper shows that the counterexamples proposed by Strong in 2008 in the Journal of Medical Ethics to Marquis's argument against abortion fail. Strong's basic idea is that there are cases--for example, terminally ill patients--where killing an adult human being is prima facie seriously morally...
International Nuclear Information System (INIS)
Goldman, M.V.
1984-01-01
After a brief discussion of beam-excited Langmuir turbulence in the solar wind, we explain the criteria for wave-particle, three-wave and strong turbulence interactions. We then present the results of a numerical integration of the Zakharov equations, which describe the strong turbulence saturation of a weak (low-density) high energy, bump-on-tail beam instability. (author)
NUCLEAR MIXING METERS FOR CLASSICAL NOVAE
Energy Technology Data Exchange (ETDEWEB)
Kelly, Keegan J.; Iliadis, Christian; Downen, Lori; Champagne, Art [Department of Physics and Astronomy, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599-3255 (United States); José, Jordi [Departament de Física i Enginyeria Nuclear, EUETIB, Universitat Politècnica de Catalunya, E-08036 Barcelona (Spain)
2013-11-10
Classical novae are caused by mass transfer episodes from a main-sequence star onto a white dwarf via Roche lobe overflow. This material possesses angular momentum and forms an accretion disk around the white dwarf. Ultimately, a fraction of this material spirals in and piles up on the white dwarf surface under electron-degenerate conditions. The subsequently occurring thermonuclear runaway reaches hundreds of megakelvin and explosively ejects matter into the interstellar medium. The exact peak temperature strongly depends on the underlying white dwarf mass, the accreted mass and metallicity, and the initial white dwarf luminosity. Observations of elemental abundance enrichments in these classical nova events imply that the ejected matter consists not only of processed solar material from the main-sequence partner but also of material from the outer layers of the underlying white dwarf. This indicates that white dwarf and accreted matter mix prior to the thermonuclear runaway. The processes by which this mixing occurs require further investigation to be understood. In this work, we analyze elemental abundances ejected from hydrodynamic nova models in search of elemental abundance ratios that are useful indicators of the total amount of mixing. We identify the abundance ratios ΣCNO/H, Ne/H, Mg/H, Al/H, and Si/H as useful mixing meters in ONe novae. The impact of thermonuclear reaction rate uncertainties on the mixing meters is investigated using Monte Carlo post-processing network calculations with temperature-density evolutions of all mass zones computed by the hydrodynamic models. We find that the current uncertainties in the {sup 30}P(p, γ){sup 31}S rate influence the Si/H abundance ratio, but overall the mixing meters found here are robust against nuclear physics uncertainties. A comparison of our results with observations of ONe novae provides strong constraints for classical nova models.
Electromagnetically induced grating with Rydberg atoms
Asghar, Sobia; Ziauddin, Qamar, Shahid; Qamar, Sajid
2016-09-01
We present a scheme to realize electromagnetically induced grating in an ensemble of strongly interacting Rydberg atoms, which act as superatoms due to the dipole blockade mechanism. The ensemble of three-level cold Rydberg-dressed (87Rb) atoms follows a cascade configuration where a strong standing-wave control field and a weak probe pulse are employed. The diffraction intensity is influenced by the strength of the probe intensity, the control field strength, and the van der Waals (vdW) interaction. It is noticed that relatively large first-order diffraction can be obtained for low-input intensity with a small vdW shift and a strong control field. The scheme can be considered as an amicable solution to realize the atomic grating at the microscopic level, which can provide background- and dark-current-free diffraction.
Escape rate for nonequilibrium processes dominated by strong non-detailed balance force
Tang, Ying; Xu, Song; Ao, Ping
2018-02-01
Quantifying the escape rate from a meta-stable state is essential to understand a wide range of dynamical processes. Kramers' classical rate formula is the product of an exponential function of the potential barrier height and a pre-factor related to the friction coefficient. Although many applications of the rate formula focused on the exponential term, the prefactor can have a significant effect on the escape rate in certain parameter regions, such as the overdamped limit and the underdamped limit. There have been continuous interests to understand the effect of non-detailed balance on the escape rate; however, how the prefactor behaves under strong non-detailed balance force remains elusive. In this work, we find that the escape rate formula has a vanishing prefactor with decreasing friction strength under the strong non-detailed balance limit. We both obtain analytical solutions in specific examples and provide a derivation for more general cases. We further verify the result by simulations and propose a testable experimental system of a charged Brownian particle in electromagnetic field. Our study demonstrates that a special care is required to estimate the effect of prefactor on the escape rate when non-detailed balance force dominates.
Massless particles, electromagnetism, and Rieffel induction
International Nuclear Information System (INIS)
Landsman, N.P.; Wiedemann, U.A.
1994-06-01
The connection between space-time covariant representations (obtained by inducing from the Lorentz group) and irreducible unitary representations (induced from Wigner's little group) of the Poincare groups is re-examined in the massless case. In the situation relevant to physics, it is found that these are related by Marsden-Weinstein reduction with respect to a gauge group. An analogous phenomenon is observed for classical massless relativistic particles. This symplectic reduction procedure can be ('second') quantized using a generalization of the Rieffel induction technique in operator algebra theory, which is carried through in detail for electromagnetism. Starting from the so-called Fermi representation of the field algebra generated by the free abelian gauge field, we construct a new ('rigged') sesquilinear form on the representation space, which is positive semi-definite, and given in terms of a Gaussian weak distribution (promeasure) on the gauge group (taken to be a Hilbert Lie group). This eventually constructs the algebra of observables of quantum electromagnetism (directly in its vacuum representation) as a representation of the so-called algebra of weak observables induced by the trivial representation of the gauge group. (orig.)
Classical radiation zeros in gauge-theory amplitudes
International Nuclear Information System (INIS)
Brown, R.W.; Kowalski, K.L.; Brodsky, S.J.
1983-01-01
The electromagnetic radiation from classical convection currents in relativistic n-particle collisions is shown to vanish in certain kinematical zones, due to complete destructive interference of the classical radiation patterns of the incoming and outgoing charged lines. We prove that quantum tree photon amplitudes vanish in the same zones, at arbitrary photon momenta including spin, seagull, and internal-line currents, provided only that the electromagnetic couplings and any other derivative couplings are as prescribed by renormalizable local gauge theory (spins + #betta# is thus explained and examples with more particles are discussed. Conditions for the null zones to lie in physical regions are established. A new radiation representation, with the zeros manifest and of practical utility independently of whether the null zones are in physical regions is derived for the complete single-photon amplitude in tree approximation, using a gauge-invariant vertex expansion stemming from new internal-radiation decomposition identities. The question of whether amplitudes with closed loops can vanish in null zones is addressed. The null zone and these relations are discussed in terms of the Bargmann-Michel-Telegdi equation. The extension from photons to general massless gauge bosons is carried out
Dielectric properties of classical and quantized ionic fluids.
Høye, Johan S
2010-06-01
We study time-dependent correlation functions of classical and quantum gases using methods of equilibrium statistical mechanics for systems of uniform as well as nonuniform densities. The basis for our approach is the path integral formalism of quantum mechanical systems. With this approach the statistical mechanics of a quantum mechanical system becomes the equivalent of a classical polymer problem in four dimensions where imaginary time is the fourth dimension. Several nontrivial results for quantum systems have been obtained earlier by this analogy. Here, we will focus upon the presence of a time-dependent electromagnetic pair interaction where the electromagnetic vector potential that depends upon currents, will be present. Thus both density and current correlations are needed to evaluate the influence of this interaction. Then we utilize that densities and currents can be expressed by polarizations by which the ionic fluid can be regarded as a dielectric one for which a nonlocal susceptibility is found. This nonlocality has as a consequence that we find no contribution from a possible transverse electric zero-frequency mode for the Casimir force between metallic plates. Further, we establish expressions for a leading correction to ab initio calculations for the energies of the quantized electrons of molecules where now retardation effects also are taken into account.
Electromagnetic compatibility in railways. Analysis and management
Energy Technology Data Exchange (ETDEWEB)
Ogunsola, Ade [Parsons Group International, Abu Dhabi (United Arab Emirates); Mariscotti, Andrea [Genoa Univ. (Italy)
2013-07-01
Recent research on electromagnetic compatibility (EMC) applied to railway systems. Focuses on the principles and application of EMC concepts to railway signalling, communications, power/traction and rolling stocks. Written by leading experts in the field. A railway is a complex distributed engineering system: the construction of a new railway or the modernisation of a existing one requires a deep understanding of the constitutive components and their interaction, inside the system itself and towards the outside world. The former covers the various subsystems (featuring a complex mix of high power sources, sensitive safety critical systems, intentional transmitters, etc.) and their interaction, including the specific functions and their relevance to safety. The latter represents all the additional possible external victims and sources of electromagnetic interaction. EMC thus starts from a comprehension of the emissions and immunity characteristics and the interactions between sources and victims, with a strong relationship to electromagnetics and to system modeling. On the other hand, the said functions are achieved and preserved and their relevance for safety is adequately handled, if the related requirements are well posed and managed throughout the process from the beginning. The link is represented by standards and their correct application, as a support to analysis, testing and demonstration.
International Nuclear Information System (INIS)
Waldron, R.A.
1980-01-01
Observations on fast mesons in cyclotrons have necessitated a revision of the earlier version of the ballistic theory. Insufficient information was available when the theory was first published to permit a unique choice of the velocity-dependent factors occurring in electromagnetic force formulas, and the forms chosen did not lead to an explanation of the decay times of fast mesons that were observed subsequently. These observations provide the information needed to permit a unique choice of the velocity-dependent factors. The new forms of the force formulae explain all observations, and lead to the conclusion that the velocities of mesons in cyclotrons are many times that of light. If these velocities could be directly measured, it would provide a method of discriminating between the Lorentz-Einstein and the ballistic theories, although it would not confirm the latter. In this revised form of the theory, magnetism appears as a residual effect of the velocity dependence of electric force laws, and the whole of electromagnetism then follows from a single basic equation, a modified form of Coulomb's law. (Auth.)
International Nuclear Information System (INIS)
Dean, S.A.
1980-01-01
Full details of the invention are given. A sensing unit assembly for an electromagnetic flux distortion flowmeter for use in liquid metal coolant of a nuclear reactor is described. The assembly comprises coils of electrically insulated conductors each wound on an individual former. The formers and coils are mounted coaxially on a spine to form at least three spaced groups arranged end to end. Each group comprises two secondary coils and an intermediate primary coil. Leads extend along a duct formed in the spine, each lead terminating at a common end. Alternative versions of the assembly are also described. The primary coil leads are connected to an alternating power supply; those for the secondary coils connected to suitable display instrumentation. When liquid metal flows along the conductor the electromagnetic field is disturbed and the induced voltage in the secondary coils is disturbed-(set at zero for no flow); the distortion depends on the rate of flow. When the induced voltage differential of at least two of the groups falls or rises outside a pre-set level a trip signal is initiated to shut down the reactor. (UK)
Does classical liberalism imply democracy?
Directory of Open Access Journals (Sweden)
David Ellerman
2015-12-01
Full Text Available There is a fault line running through classical liberalism as to whether or not democratic self-governance is a necessary part of a liberal social order. The democratic and non-democratic strains of classical liberalism are both present today—particularly in the United States. Many contemporary libertarians and neo-Austrian economists represent the non-democratic strain in their promotion of non-democratic sovereign city-states (start-up cities or charter cities. We will take the late James M. Buchanan as a representative of the democratic strain of classical liberalism. Since the fundamental norm of classical liberalism is consent, we must start with the intellectual history of the voluntary slavery contract, the coverture marriage contract, and the voluntary non-democratic constitution (or pactum subjectionis. Next we recover the theory of inalienable rights that descends from the Reformation doctrine of the inalienability of conscience through the Enlightenment (e.g. Spinoza and Hutcheson in the abolitionist and democratic movements. Consent-based governments divide into those based on the subjects’ alienation of power to a sovereign and those based on the citizens’ delegation of power to representatives. Inalienable rights theory rules out that alienation in favor of delegation, so the citizens remain the ultimate principals and the form of government is democratic. Thus the argument concludes in agreement with Buchanan that the classical liberal endorsement of sovereign individuals acting in the marketplace generalizes to the joint action of individuals as the principals in their own organizations.
Doing classical theology in context
Directory of Open Access Journals (Sweden)
Gerrit Neven
2007-05-01
Full Text Available This article is about doing classical theology in context. The weight of my argument is that classical text of Karl Barth’s theology is great intellectual text means: being addressed by this text in the context in which one lives. The basic keywords that constitute a rule for reading those texts are “equality”, “event” and “re-contextualisation”. The article contains two sections: The first section elaborates statements about the challenge of the event and the project of rereading classics by way of recontextualisation. The word “event” refers to true and innovating moments in history which one can share, or which one can betray. Classical texts always share in those liberative moments. The question then is in what sense do they present a challenge to the contemporary reader. The second section elaborates the position of man as central and all decisive for doing theology in context now. In this section, the author appeals for a renewal of the classical anthropology as an anthropology of hope. This anthropology contradicts postmodern concepts of otherness.
Classical approach in atomic physics
International Nuclear Information System (INIS)
Solov'ev, E.A.
2011-01-01
The application of a classical approach to various quantum problems - the secular perturbation approach to quantization of a hydrogen atom in external fields and a helium atom, the adiabatic switching method for calculation of a semiclassical spectrum of a hydrogen atom in crossed electric and magnetic fields, a spontaneous decay of excited states of a hydrogen atom, Gutzwiller's approach to Stark problem, long-lived excited states of a helium atom discovered with the help of Poincare section, inelastic transitions in slow and fast electron-atom and ion-atom collisions - is reviewed. Further, a classical representation in quantum theory is discussed. In this representation the quantum states are treated as an ensemble of classical states. This approach opens the way to an accurate description of the initial and final states in classical trajectory Monte Carlo (CTMC) method and a purely classical explanation of tunneling phenomenon. The general aspects of the structure of the semiclassical series such as renormalization group symmetry, criterion of accuracy and so on are reviewed as well. (author)
QCD : the theory of strong interactions Conference MT17
2001-01-01
The theory of strong interactions,Quantum Chromodynamics (QCD), predicts that the strong interaction is transmitted by the exchange of particles called gluons. Unlike the messengers of electromagnetism photons, which are electrically neutral - gluons carry a strong charge associated with the interaction they mediate. QCD predicts that the strength of the interaction between quarks and gluons becomes weaker at higher energies. LEP has measured the evolution of the strong coupling constant up to energies of 200 GeV and has confirmed this prediction.
QCD : the theory of strong interactions Exhibition LEPFest 2000
2000-01-01
The theory of strong interactions,Quantum Chromodynamics (QCD),predicts that the strong interac- tion is transmitted by the exchange of particles called glu- ons.Unlike the messengers of electromagnetism -pho- tons,which are electrically neutral -gluons carry a strong charge associated with the interaction they mediate. QCD predicts that the strength of the interaction between quarks and gluons becomes weaker at higher energies.LEP has measured the evolution of the strong coupling constant up to energies of 200 GeV and has confirmed this prediction.