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  • 1.
    Lehnert, Bo
    KTH, School of Electrical Engineering (EES), Fusion Plasma Physics. KTH, School of Electrical Engineering (EES), Centres, Alfvén Laboratory Centre for Space and Fusion Plasma Physics.
    A Possible Interpretation of Dark Energy and Matter of the Expanding Universe2009In: NEW DEVELOPMENTS IN NONLINEAR PLASMA PHYSICS  / [ed] Eliasson B; Shukla PK, 2009, Vol. 1188, p. 345-355Conference paper (Refereed)
    Abstract [en]

    At present the expanding universe is observed to be dominated by the not fully understood concepts of dark energy and matter, in a conceived almost flat Euclidian geometry. As one of the possible efforts to understand its global behaviour, the present paper attempts to explain these concepts in terms of the pressure force and gravity of a spherical photon gas cloud of zero point energy, in flat geometry. A difficult point concerns the frequency distribution of the zero point energy oscillations which leads to the unacceptable result of an infinite total energy. A modification of this distribution is therefore proposed which results in finite energy density. A corresponding equilibrium is investigated, as well as small dynamic deviations from it, to form a basis for a model of the expanding universe. Provided that the crucial points of the present approach hold true, the model satisfies the requirements of cosmic linear dimensions, results in an estimated acceleration of the expansion being of the order of the observed one, presents a possible solution of the coincidence problem of dark energy and matter, and provides one of the possible explanations of the observed excess of high-energy electrons and positrons in recent balloon and satellite experiments.

  • 2.
    Lehnert, Bo
    KTH, School of Electrical Engineering (EES), Centres, Alfvén Laboratory Centre for Space and Fusion Plasma Physics. KTH, School of Electrical Engineering (EES), Fusion Plasma Physics.
    Boundary conditions and spin of a dense light beam2006In: Physica Scripta, ISSN 0031-8949, E-ISSN 1402-4896, Vol. 74, no 1, p. 139-144Article in journal (Refereed)
    Abstract [en]

    A light beam of high photon density and spatially limited cross-section is analysed with respect to its boundary conditions and angular momentum ( spin). For Maxwell's equations in a vacuum state of vanishing electrical field divergence, the exact solutions are found not to be reconcilable with a beam having a limited cross-section and a nonzero spin. Transverse spatial beam derivatives only become possible as an approximation when their characteristic lengths are very large as compared to the relevant wavelengths, but even then there is no spin. A revised electromagnetic theory, based on a nonzero electric field divergence in the vacuum state, leads on the other hand to beam configurations for which there can exist strong transverse derivatives in a boundary region, as well as a nonzero spin. The Poynting vector then has components both in the axial direction of propagation and in the transverse direction along the boundary. The angular momentum, being imagined as an equivalent sum of momenta of the individual photons in the beam interior, is then replaced by a real spin generated and localized in the boundary layer.

  • 3.
    Lehnert, Bo
    KTH, Superseded Departments, Alfvén Laboratory.
    Complementary Aspects on Matter-Antimatter Boundary Layers1990Report (Other academic)
  • 4.
    Lehnert, Bo
    KTH, School of Electrical Engineering (EES), Fusion Plasma Physics. KTH, School of Electrical Engineering (EES), Centres, Alfvén Laboratory Centre for Space and Fusion Plasma Physics.
    Cosmic equilibrium of a photon gas in its gravitational field2008In: Advanced Studies in Theoretical Physics, ISSN 1313-1311, E-ISSN 1314-7609, Vol. 2, no 17, p. 837-843Article in journal (Refereed)
    Abstract [en]

    Recent research indicates that the universe is expanding at an accelerated rate, and that dark energy and dark matter are underlying such a behaviour. In this paper the proposal is made that dark energy and matter are due to the zero point energy of a photon gas and its related Casimir force. For cosmical dimensions an equilibrium is shown to exist within such a gas, in the form of a balance between its pressure and gravitational forces. With commonly accepted values of the parameters involved, there is further an indication that the universe should be somewhat off such an equilibrium, and be governed by a pressure-dominated accelerated state. The obtained numerical results depend critically on the effective spectral contribution to the zero point pressure. Expansion at a constant rate is only possible at special conditions. This analysis can also be modified to apply to the hot photon gas prevailing during the earliest stages of the expansion, thereby leading to a strongly reduced characteristic radius within the parameter range of an equilibrium.

  • 5.
    Lehnert, Bo
    KTH, School of Electrical Engineering (EES), Fusion Plasma Physics. KTH, School of Electrical Engineering (EES), Centres, Alfvén Laboratory Centre for Space and Fusion Plasma Physics.
    Dark energy and dark matter as due to zero point energy2013In: Journal of Plasma Physics, ISSN 0022-3778, E-ISSN 1469-7807, Vol. 79, no 3, p. 327-334Article in journal (Refereed)
    Abstract [en]

    An attempt is made to explain dark energy and dark matter of the expanding universe in terms of the zero point vacuum energy. This analysis is mainly limited to later stages of an observable nearly flat universe. It is based on a revised formulation of the spectral distribution of the zero point energy, for an ensemble in a defined statistical equilibrium having finite total energy density. The steady and dynamic states are studied for a spherical cloud of zero point energy photons. The 'antigravitational' force due to its pressure gradient then represents dark energy, and its gravitational force due to the energy density represents dark matter. Four fundamental results come out of the theory. First, the lack of emitted radiation becomes reconcilable with the concepts of dark energy and dark matter. Second, the crucial coincidence problem of equal orders of magnitude of mass density and vacuum energy density cannot be explained by the cosmological constant, but is resolved by the present variable concepts, which originate from the same photon gas balance. Third, the present approach becomes reconcilable with cosmical dimensions and with the radius of the observable universe. Fourth, the deduced acceleration of the expansion agrees with the observed one. In addition, mass polarity of a generalized gravitation law for matter and antimatter is proposed as a source of dark flow.

  • 6.
    Lehnert, Bo
    KTH, School of Electrical Engineering (EES), Fusion Plasma Physics. KTH, School of Electrical Engineering (EES), Centres, Alfvén Laboratory Centre for Space and Fusion Plasma Physics.
    Early magnetohydrodynamic research in Stockholm2007In: Magnetohydrodynamics: Historical Evolution and Trends / [ed] Molokov, S; Moreau, R; Moffatt, HK, DORDRECHT: SPRINGER , 2007, Vol. 80, p. 27-36Conference paper (Refereed)
  • 7.
    Lehnert, Bo
    KTH, Superseded Departments, Alfvén Laboratory.
    Extended electromagnetic theory: New solutions of old problems2004In: PIERS - Progress Electromagn. Res. Symp., Ext. Pap. Proc., 2004, p. 811-814Conference paper (Refereed)
  • 8.
    Lehnert, Bo
    KTH, School of Electrical Engineering (EES), Fusion Plasma Physics. KTH, School of Electrical Engineering (EES), Centres, Alfvén Laboratory Centre for Space and Fusion Plasma Physics.
    Half a century of fusion research towards ITER2013In: Physica Scripta, ISSN 0031-8949, E-ISSN 1402-4896, Vol. 87, no 1, p. 018201-Article in journal (Refereed)
    Abstract [en]

    A review is given on plasma physics and controlled thermonuclear fusion research since the late 1950s and up to the present day. Special emphasis is given to various proposed magnetic plasma confinement systems, as well as to the research aiming at the planned International Thermonuclear Experimental Reactor (ITER) project. The latter is based on the tokamak field geometry of a strong toroidal magnetic field, combined with an inductively imposed toroidal plasma current. Experimental and theoretical research has been conducted on the fundamental problems of confinement, equilibrium, stability, plasma transport and plasma heating. During this development two milestones have been passed on the way to ITER, namely the removed threat by Bohm diffusion at the end of the 1960s, and the discovery of the High Mode at the beginning of the 1980s. Finally, some future perspectives are shortly given on this line of research.

  • 9.
    Lehnert, Bo
    KTH, School of Electrical Engineering (EES), Centres, Alfvén Laboratory Centre for Space and Fusion Plasma Physics.
    Non-existence of photon spin in conventional theory2006In: Communications in Applied Analysis, ISSN 1083-2564, Vol. 10, no 1, p. 79-84Article in journal (Refereed)
    Abstract [en]

    Maxwell's equations have been used as a guideline in conventional quantum electrodynamics. Also the related Poynting vector has thereby formed the basis for the quantized field momentum. In this letter the conventional theory is applied to the model of a unidirectionally propagating photon, as described in a cylindrical frame of reference. Due to the vanishing electric field divergence of Maxwell's equations in the vacuum, the photon field is then found to be purely transverse, having a Poynting vector and energy flow in the axial direction of propagation only, and leading to the unacceptable result of a nonexisting angular momentum (spin). One possible way of avoiding this shortcoming is provided by a revised electromagnetic theory which includes the additional degree of freedom of a nonzero electric field divergence in the vacuum state.

  • 10.
    Lehnert, Bo
    KTH, School of Electrical Engineering (EES), Fusion Plasma Physics. KTH, School of Electrical Engineering (EES), Centres, Alfvén Laboratory Centre for Space and Fusion Plasma Physics.
    On a flat expanding universe2013In: Advanced Studies in Theoretical Physics, ISSN 1313-1311, E-ISSN 1314-7609, Vol. 7, no 1-4, p. 191-197Article in journal (Refereed)
    Abstract [en]

    An earlier elaborated model of the expanding universe with its contents of dark energy, dark matter and normal matter is reconsidered and extended. The model is found to be reconcilable with the observed cosmical dimensions and with the magnitude of the present accelerated expansion. It has the form of a freely expanding cloud of zero-pointenergy photons, with the inclusion of a small amount of normal matter. On a macroscopic scale, within the radius of the observable universe, the model has the character of a flat Euclidian geometry, without the need of introducing curved space effects due to General Relativity. This flat geometry is found to be stable with respect to expansive and compressive perturbations, thus suggesting the universe to possess an intrinsic mechanism which aims at flat geometry.

  • 11.
    Lehnert, Bo
    KTH, School of Electrical Engineering (EES), Fusion Plasma Physics. KTH, School of Electrical Engineering (EES), Centres, Alfvén Laboratory Centre for Space and Fusion Plasma Physics.
    On angular momentum and rest mass of the photon2013In: Journal of Plasma Physics, ISSN 0022-3778, E-ISSN 1469-7807, Vol. 79, no 6, p. 1133-1135Article in journal (Refereed)
    Abstract [en]

    A reconsideration is made on the basic concepts of the individual photon, including its angular momentum (spin) and a possibly existing very small rest mass. In terms of conventional classical theory, as well as of its quantum mechanical counterpart, the results from a so far established Standard Model of an empty vacuum state are not found to be reconcilable with an experimentally relevant photon model. The main properties of such a model would on the other hand become compatible with the results of a recently established revised quantum electrodynamic theory based on a non-zero electric field divergence in the vacuum and a corresponding symmetry breaking of the electromagnetic field.

  • 12.
    Lehnert, Bo
    KTH, Superseded Departments.
    On the Extremum Electric Charge Problem of Steady Electromagnetic Equilibria1989Report (Other academic)
  • 13.
    Lehnert, Bo
    KTH, School of Electrical Engineering (EES), Fusion Plasma Physics. KTH, School of Electrical Engineering (EES), Centres, Alfvén Laboratory Centre for Space and Fusion Plasma Physics.
    Revised quantum electrodynamics2012Book (Other academic)
    Abstract [en]

    The underlying ideas of the present treatise originate from some speculations by the author in the late 1960s on the possible existence of a nonzero electric field divergence in the electromagnetic equations of the vacuum state. From these speculations an extended electromagnetic theory with fundamental applications was gradually developed, and finally debouching into the present updated and revised quantum electrodynamic approach. This book collects the various and separately published parts of the theory into one systematic entity.

  • 14.
    Lehnert, Bo
    KTH, School of Electrical Engineering (EES), Centres, Alfvén Laboratory Centre for Space and Fusion Plasma Physics. KTH, School of Electrical Engineering (EES), Fusion Plasma Physics.
    Screw-shaped light in extended electromagnetics2005In: Physica Scripta, ISSN 0031-8949, E-ISSN 1402-4896, Vol. 72, no 5, p. 359-365Article in journal (Refereed)
    Abstract [en]

    Twisted light beams have recently been observed for which the energy travels ill a corkscrew-shaped path. spiralling around the beam's central axis. These discoveries arc expected to become important to the development of new methods in the field of communication. as well as to the invention of new tools in microbiology. In this paper is shown that conventional theory based oil Maxwell's equations cannot explain the basic features of twisted light. On the other hand an extended electromagnetic theory, based oil a nonzero electric field divergence in the vacuum state. appears to be reconcilable with the main behaviour of the twisted light phenomena. The solutions and the set of modes being obtained from this extended theory are applicable both to models of high and low density photon beams and to those of individual photons. all having limited extensions in space and possessing an angular momentum (spin). Thereby beam models call be developed the intensity of which forms a ring-shaped cross-section, and individual photon models call be obtained which have the features of "needle radiation". However. within the limits of validity of the approximations made so far in the analysis. it is not clear whether the effective diameter of the individual photon models call he small enough to approach atomic dimensions.

  • 15.
    Lehnert, Bo
    KTH, Superseded Departments, Alfvén Laboratory.
    The electron as a steady-state confinement system2004In: Physica Scripta, ISSN 0031-8949, E-ISSN 1402-4896, Vol. T113, p. 41-44Article in journal (Refereed)
    Abstract [en]

    An extended Lorentz invariant electromagnetic theory includes the additional degree of freedom provided by a nonzero electric charge density and an associated electric field divergence in the vacuum state. The theory is applied to an electron model of a steady electromagnetic state. Three new physical features come out of this analysis. First, a steady equilibrium can be established, by which the electron is prevented from "exploding" under the action of its self-charge, as otherwise being predicted by conventional theory. Second, a variational analysis with imposed subsidiary quantum conditions ends up in a parameter range where the deduced charge becomes nearly equal to the experimentally determined elementary charge. Independently of this, the radial balance of forces in the equilibrium state leads to a value of the charge in the same range, thereby deviating by only one percent from the experimental one. Third, this deviation may possibly become removed by a quantum mechanical correction. If this would come out to be true, the elementary free charge would no longer remain an independent constant of nature, but becomes determined by the velocity of light, Planck's constant, and the dielectric constant only.

  • 16.
    Lehnert, Bo
    KTH, Superseded Departments.
    The Transition of an Extended Electromagnetic Field Approach to Conventional Theory1989Report (Other academic)
  • 17.
    Lehnert, Bo
    KTH, School of Electrical Engineering (EES), Fusion Plasma Physics. KTH, School of Electrical Engineering (EES), Centres, Alfvén Laboratory Centre for Space and Fusion Plasma Physics.
    Wave-Particle Properties and Pair Formation of the Photon2008In: Frontiers In Modern Plasma Physics / [ed] Shukla, PK; Eliasson, B; Stenflo, L, 2008, Vol. 1061, p. 282-291Conference paper (Refereed)
    Abstract [en]

    Models of an individual photon having joint wave-particle properties, needle-like geometry, and spin cannot be based on conventional theory, but be deduced in terms of a revised quantum electrodynamic approach. In this paper the latter is applied to two-slit configurations and electron-positron pair formation: (a) Two-slit experiments performed earlier by Tsuchiya et al. and recently by Afshar et al. demonstrate the joint wave-particle properties of the individual photon, and agree with Einstein's argument against Complementarity. The present theory is consistent with these results. (b) The elementary electron-positron pair formation process is considered, with special attention to the involved orbits, conservation of energy, spin, and electric charge. The obtained model appears to be consistent with the process in which the created electron and positron move along two rays and have original directions along the path of the incoming photon. The nonzero electric field divergence of the theory is associated with all intrinsic local electric charge density. This may explain that the photon call decay oil account of the impact from all external electric field.

  • 18.
    Lehnert, Bo
    KTH, School of Electrical Engineering (EES), Fusion Plasma Physics. KTH, School of Electrical Engineering (EES), Centres, Alfvén Laboratory Centre for Space and Fusion Plasma Physics.
    Zero Point Energy as Origin of Dark Energy and Dark Matter2012In: Joint ITER-IAEA-ICTP Advanced Workshop on Fusion and Plasma Physics / [ed] Shukla, PK; Eliasson, B, American Institute of Physics (AIP), 2012, p. 102-114Conference paper (Refereed)
    Abstract [en]

    An attempt is made to explain dark energy and dark matter of the expanding universe in terms of the zero point vacuum energy. This analysis is mainly limited to later stages of an observable nearly flat universe. It is based on a revised formulation of the spectral distribution of the zero point energy, for an ensemble in a defined statistical equilibrium having finite total energy density. The steady and dynamic states are studied for a spherical cloud of zero point energy photons. The "antigravitational" force due to its pressure gradient then represents dark energy, and its gravitational force due to the energy density represents dark matter. Four fundamental results come out of the theory. First, the lack of emitted radiation becomes reconcilable with the concepts of dark energy and dark matter. Second, the crucial coincidence problem of equal orders of magnitude of mass density and vacuum energy density cannot be explained by the cosmological constant, but is resolved by the present variable concepts which originate from the same photon gas balance. Third, the present approach becomes reconcilable with cosmical dimensions and with the radius of the observable universe. Fourth, the deduced acceleration of the expansion agrees with the observed one.

  • 19.
    Lehnert, Bo
    et al.
    KTH, School of Electrical Engineering (EES), Fusion Plasma Physics.
    Höök, L. Josef
    KTH, School of Electrical Engineering (EES), Fusion Plasma Physics.
    An electron model with elementary charge2010In: Journal of Plasma Physics, ISSN 0022-3778, E-ISSN 1469-7807, Vol. 76, no 3-4, p. 419-428Article in journal (Refereed)
    Abstract [en]

    An earlier elaborated model of the electron, being based on a revised quantum electrodynamic theory, is further investigated in terms of an improved numerical iteration scheme. This point-charge-like model is based on the "infinity" of a divergent generating function being balanced by the "zero" of a shrinking characteristic radius. This eliminates the self-energy problem. According to the computations, the quantum conditions on spin, magnetic moment, and magnetic flux, plus the requirement of an elementary charge having the experimental value, can all be satisfied within rather narrow limits by a single scalar parameter. The revised model prevents the electron from "exploding" due to its eigencharge.

1 - 19 of 19
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