The Experts below are selected from a list of 324 Experts worldwide ranked by ideXlab platform

Masud Mansuripur - One of the best experts on this subject based on the ideXlab platform.

  • Force torque linear momentum and angular momentum in classical electrodynamics
    Applied Physics A, 2017
    Co-Authors: Masud Mansuripur
    Abstract:

    The classical theory of electrodynamics is built upon Maxwell’s equations and the concepts of electromagnetic (EM) field, Force, energy, and momentum, which are intimately tied together by Poynting’s theorem and by the Lorentz Force Law. Whereas Maxwell’s equations relate the fields to their material sources, Poynting’s theorem governs the flow of EM energy and its exchange between fields and material media, while the Lorentz Law regulates the back-and-forth transfer of momentum between the media and the fields. An alternative Force Law, first proposed by Einstein and Laub, exists that is consistent with Maxwell’s equations and complies with the conservation Laws as well as with the requirements of special relativity. While the Lorentz Law requires the introduction of hidden energy and hidden momentum in situations where an electric field acts on a magnetized medium, the Einstein–Laub (E–L) formulation of EM Force and torque does not invoke hidden entities under such circumstances. Moreover, total Force/torque exerted by EM fields on any given object turns out to be independent of whether the density of Force/torque is evaluated using the Law of Lorentz or that of Einstein and Laub. Hidden entities aside, the two formulations differ only in their predicted Force and torque distributions inside matter. Such differences in distribution are occasionally measurable, and could serve as a guide in deciding which formulation, if either, corresponds to physical reality.

  • the Force Law of classical electrodynamics lorentz versus einstein and laub
    Frontiers in Optics, 2014
    Co-Authors: Masud Mansuripur
    Abstract:

    We discuss the advantages of the Force Law proposed by Einstein and Laub in 1908 over the standard Force Law of Lorentz. The Einstein-Laub Law is consistent with Maxwell’s equations, with the conservation Laws, and with special relativity.

  • the lorentz Force Law and its connections to hidden momentum the einstein laub Force and the aharonov casher effect
    arXiv: Classical Physics, 2014
    Co-Authors: Masud Mansuripur
    Abstract:

    The Lorentz Force of classical electrodynamics, when applied to magnetic materials, gives rise to hidden energy and hidden momentum. Removing the contributions of hidden entities from the Poynting vector, from the electromagnetic momentum density, and from the Lorentz Force and torque densities simplifies the equations of the classical theory. In particular, the reduced expression of the electromagnetic Force-density becomes very similar (but not identical) to the Einstein-Laub expression for the Force exerted by electric and magnetic fields on a distribution of charge, current, polarization and magnetization. Examples reveal the similarities and differences among various equations that describe the Force and torque exerted by electromagnetic fields on material media. An important example of the simplifications afforded by the Einstein-Laub formula is provided by a magnetic dipole moving in a static electric field and exhibiting the Aharonov-Casher effect.

  • the lorentz Force Law and its connections to hidden momentum the einstein laub Force and the aharonov casher effect
    IEEE Transactions on Magnetics, 2014
    Co-Authors: Masud Mansuripur
    Abstract:

    The Lorentz Force of classical electrodynamics, when applied to magnetic materials, gives rise to hidden energy and hidden momentum. Removing the contributions of hidden entities from the Poynting vector, from the electromagnetic (EM) momentum density, and from the Lorentz Force and torque densities simplifies the equations of the classical theory. In particular, the reduced expression of the EM Force density becomes very similar (but not identical) to the Einstein-Laub expression for the Force exerted by electric and magnetic fields on a distribution of charge, current, polarization, and magnetization. Examples reveal the similarities and differences among various equations that describe the Force and torque exerted by EM fields on material media. An important example of the simplifications afforded by the Einstein-Laub formula is provided by a magnetic dipole moving in a static electric field and exhibiting the Aharonov-Casher effect.

  • the Force Law of classical electrodynamics lorentz versus einstein and laub
    Proceedings of SPIE, 2013
    Co-Authors: Masud Mansuripur
    Abstract:

    The classical theory of electrodynamics is built upon Maxwell’s equations and the concepts of electromagnetic field, Force, energy, and momentum, which are intimately tied together by Poynting’s theorem and the Lorentz Force Law. Whereas Maxwell’s macroscopic equations relate the electric and magnetic fields to their material sources (i.e., charge, current, polarization and magnetization), Poynting’s theorem governs the flow of electromagnetic energy and its exchange between fields and material media, while the Lorentz Law regulates the backand- forth transfer of momentum between the media and the fields. As it turns out, an alternative Force Law, first proposed in 1908 by Einstein and Laub, exists that is consistent with Maxwell’s macroscopic equations and complies with the conservation Laws as well as with the requirements of special relativity. While the Lorentz Law requires the introduction of hidden energy and hidden momentum in situations where an electric field acts on a magnetic material, the Einstein-Laub formulation of electromagnetic Force and torque does not invoke hidden entities under such circumstances. Moreover, the total Force and the total torque exerted by electromagnetic fields on any given object turn out to be independent of whether Force and torque densities are evaluated using the Lorentz Law or in accordance with the Einstein-Laub formulas. Hidden entities aside, the two formulations differ only in their predicted Force and torque distributions throughout material media. Such differences in distribution are occasionally measurable, and could serve as a guide in deciding which formulation, if either, corresponds to physical reality.

John E Sader - One of the best experts on this subject based on the ideXlab platform.

  • Interatomic Force Laws that evade dynamic measurement
    Nature Nanotechnology, 2018
    Co-Authors: John E Sader, Ferdinand Huber, Barry D. Hughes, Franz J Giessibl
    Abstract:

    Measurement of the Force between two atoms is performed routinely with the atomic Force microscope. The shape of this interatomic Force Law is now found to directly regulate this capability: rapidly varying interatomic Force Laws, which are common in nature, can corrupt their own measurement.

  • accurate formulas for interaction Force and energy in frequency modulation Force spectroscopy
    Applied Physics Letters, 2004
    Co-Authors: John E Sader, Suzanne P Jarvis
    Abstract:

    Frequency modulation atomic Force microscopy utilizes the change in resonant frequency of a cantilever to detect variations in the interaction Force between cantilever tip and sample. While a simple relation exists enabling the frequency shift to be determined for a given Force Law, the required complementary inverse relation does not exist for arbitrary oscillation amplitudes of the cantilever. In this letter we address this problem and present simple yet accurate formulas that enable the interaction Force and energy to be determined directly from the measured frequency shift. These formulas are valid for any oscillation amplitude and interaction Force, and are therefore of widespread applicability in frequency modulation dynamic Force spectroscopy.

Tolga Yarman - One of the best experts on this subject based on the ideXlab platform.

  • Force Law in material media hidden momentum and quantum phases
    Annals of Physics, 2016
    Co-Authors: A L Kholmetskii, O Missevitch, Tolga Yarman
    Abstract:

    Abstract We address to the Force Law in classical electrodynamics of material media, paying attention on the Force term due to time variation of hidden momentum of magnetic dipoles. We highlight that the emergence of this Force component is required by the general theorem, deriving zero total momentum for any static configuration of charges/currents. At the same time, we disclose the impossibility to add this Force term covariantly to the Lorentz Force Law in material media. We further show that the adoption of the Einstein–Laub Force Law does not resolve the issue, because for a small electric/magnetic dipole, the density of Einstein–Laub Force integrates exactly to the same equation, like the Lorentz Force with the inclusion of hidden momentum contribution. Thus, none of the available expressions for the Force on a moving dipole is compatible with the relativistic transformation of Force, and we support this statement with a number of particular examples. In this respect, we suggest applying the Lagrangian approach to the derivation of the Force Law in a magnetized/polarized medium. In the framework of this approach we obtain the novel expression for the Force on a small electric/magnetic dipole, with the novel expression for its generalized momentum. The latter expression implies two novel quantum effects with non-topological phases, when an electric dipole is moving in an electric field, and when a magnetic dipole is moving in a magnetic field. These phases, in general, are not related to dynamical effects, because they are not equal to zero, when the classical Force on a dipole is vanishing. The implications of the obtained results are discussed.

  • Force Law in material media and quantum phases
    EPL, 2016
    Co-Authors: A L Kholmetskii, O Missevitch, Tolga Yarman
    Abstract:

    We show that the known expressions for the Force on a point-like dipole are incompatible with the relativistic transformation of Force, and in this respect we apply the Lagrangian approach to the derivation of the correct equation for Force on a small electric/magnetic dipole. The obtained expression for the generalized momentum of a moving dipole predicts two novel quantum effects with non-topological and non-dynamic phases, when an electric dipole is moving in an electric field, and when a magnetic dipole is moving in a magnetic field, respectively.

Franz J Giessibl - One of the best experts on this subject based on the ideXlab platform.

  • Interatomic Force Laws that evade dynamic measurement
    Nature Nanotechnology, 2018
    Co-Authors: John E Sader, Ferdinand Huber, Barry D. Hughes, Franz J Giessibl
    Abstract:

    Measurement of the Force between two atoms is performed routinely with the atomic Force microscope. The shape of this interatomic Force Law is now found to directly regulate this capability: rapidly varying interatomic Force Laws, which are common in nature, can corrupt their own measurement.

A L Kholmetskii - One of the best experts on this subject based on the ideXlab platform.

  • Force Law in material media hidden momentum and quantum phases
    Annals of Physics, 2016
    Co-Authors: A L Kholmetskii, O Missevitch, Tolga Yarman
    Abstract:

    Abstract We address to the Force Law in classical electrodynamics of material media, paying attention on the Force term due to time variation of hidden momentum of magnetic dipoles. We highlight that the emergence of this Force component is required by the general theorem, deriving zero total momentum for any static configuration of charges/currents. At the same time, we disclose the impossibility to add this Force term covariantly to the Lorentz Force Law in material media. We further show that the adoption of the Einstein–Laub Force Law does not resolve the issue, because for a small electric/magnetic dipole, the density of Einstein–Laub Force integrates exactly to the same equation, like the Lorentz Force with the inclusion of hidden momentum contribution. Thus, none of the available expressions for the Force on a moving dipole is compatible with the relativistic transformation of Force, and we support this statement with a number of particular examples. In this respect, we suggest applying the Lagrangian approach to the derivation of the Force Law in a magnetized/polarized medium. In the framework of this approach we obtain the novel expression for the Force on a small electric/magnetic dipole, with the novel expression for its generalized momentum. The latter expression implies two novel quantum effects with non-topological phases, when an electric dipole is moving in an electric field, and when a magnetic dipole is moving in a magnetic field. These phases, in general, are not related to dynamical effects, because they are not equal to zero, when the classical Force on a dipole is vanishing. The implications of the obtained results are discussed.

  • Force Law in material media and quantum phases
    EPL, 2016
    Co-Authors: A L Kholmetskii, O Missevitch, Tolga Yarman
    Abstract:

    We show that the known expressions for the Force on a point-like dipole are incompatible with the relativistic transformation of Force, and in this respect we apply the Lagrangian approach to the derivation of the correct equation for Force on a small electric/magnetic dipole. The obtained expression for the generalized momentum of a moving dipole predicts two novel quantum effects with non-topological and non-dynamic phases, when an electric dipole is moving in an electric field, and when a magnetic dipole is moving in a magnetic field, respectively.