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1.
Im Anschluß an ein von Woltjer [1] diskutiertes Variationsproblem wird gezeigt: Die Euler-Lagrange-Gleichungen des Variationsproblems mit der Nebenbedingung wo H = rot A gesetzt ist, sind die Differentialgleichungen der kraftfreien Magnetfelder mit variablem α. Die Nebenbedingung läßt sich für alle Felder H erfüllen, die keinen singulären Punkt mit H = 0 in dem betrachteten Volumen V haben. In persuance of a variational principle discussed by Woltjer [1] it is shown that the Euler-Lagrange-equations of the variational problem with the secondary condition where H = rot A are the differential equations of the force-free magnetic fields with a variable scalar α. The secondary condition can be accomplished for all magnetic fields which do not contain singular points with H = 0 in the volume V under consideration.  相似文献   

2.
The post-NEWTON ian approximation of the gravo-dynamics of planetary motions is given by a LAGRANG ian . For ε = 1/8, β = 3/2 und γ = ?1/2 this LAGRANG ian is the well-know function for EINSTEIN 's geodesic motion in an isotropic SCHWARZSCHILD metric. The perihel motion is given by TISSERAND 's formula   相似文献   

3.
The equations of a rotationally symmetric, static, incompressible plasma with infinite conductivity are equivalent to an elliptic differential equation for the function where p means the pressure, ? the density, and Φ the potential of the external forces. Moreover this differential equality contains two arbitrary functions of ξ. When ξ?2 + ξ?2 < 0, both arbitrary functions can be computed from the boundary values of Hφ und H⊥ (the component of H , which is perpendicular to the boundary).  相似文献   

4.
It is shown that each non-flat regular static asymptotically flat solution of the gravitational field equation following from the Lagrangian has in a certain sense positive energy. Further, for a set of parameters including the BACH -EINSTEIN theory some results concerning the full nonlinear behaviour of the solutions of the field equation will be given.  相似文献   

5.
An elementary criterion of the stability of a matter sphere against gravitational collapse is given by the circular velocity condition of POINCARÉ : In a space with a spherically symmetric gravitation potential ? (r) and with a spherically symmetric metric gik (e.g., a SCHWARZSCHILD space time) the circular velocity V* of a particle on the surface r = R of the matter-sphere must be (This condition is a consequence of the virial theorem and of the POINCARÉ theorem.) - However, EINSTEIN 's axiom of causality implies that this velocity V* must be smaller than the local velocity of light v: V*2 < v2. And this local velocity v is a function of the gravitation potential ?, too: v = v [?]. In the case of NEWTON 's or EINSTEIN 's theory the spherically symmetric gravitation potential is given by the NEWTON ian function ? = fM/r. In the special theory of relativity, we would have v = c (c = EINSTEIN 's fundamental velocity) and grr = 1. Therefore, the specialrelativistic stability condition is R > fMc?2. - But in the NEWTON ian theory v is depending of the gravitation potential and depends of the boundary condition for the light propagation, also. According to the ansatz of LAPLACE (1799) we have: (emanation-theory of light). But, according to SOLDNER (1801), we have Therefore, we are finding in the case of LAPLACE the same condition R > fMc?2 as in the SRT. But, in the case of SOLDER 's ansatz non condition for stability is resulting. - In the general relativistic theories the local velocity of light is given by EINSTEIN 's expression According to EINSTEIN 's theory of “static gravitation” (1911/12) we have grr = 1 and therefore the formula and according to the GRT (with - gω = grr?1) we have the formula Therefore, the Hilbert-Laue condition r= R > 3fMc?2 results as stability condition. From the gravo-optical point of view, in GRT and for the classical ansatz of LAPLACE “black-holes” with bounding states of light result for R ≤ 2fM?2. But, no “black-holes” are existing according to SOLDNER 's ansatz. However, in GRT each black-hole must be a “collapsar”. But according to the classical theory of LAPLACE we have uncollapsed “black- holes” for the domain .  相似文献   

6.
Using hydrodynamical model of the two-electron-temperatere plasma, the analytical investigation of parametric instability of electron-acoustic wave has been made. It is found that the growth rate decreases with increasing concentration ratio of the hot to the total electrons nh0/n0. The growth rate is found to be more for   相似文献   

7.
The question of the existence and uniqueness of the solutions of the system in case of rotational symmetry can be reduced to the question of the resolvibility of a nonlinear elliptic differential equation for α which contains an arbitrary function g(α). Under rather general suppositions the boundary values of α and the function g(α) are given by the boundary values of H⊥ and H φ (the component of H which is perpendicular to the boundary). From the theory of non-linear elliptic equations one obtains: In sufficiently small domains the boundary value problem has a unique solution. For large domains these exist estimations about the diameter and area which guarantee the existence and uniqueness of the solutions.  相似文献   

8.
In our papers, TREDER [1, 2] we have formulated a unified electrodynamics of the fourth order with bi-wave equations for the vector potential A. In this electrodynamics EINSTEIN ian photon and heavy W-mesons are the field quanta. In correspondence to this field theory we are able to formulate a unified theory of gravitation, too. The field equations for the gravitational metrics grr in this theory are corresponding with the EINSTEIN equations of General Relativity in the same way like the electromagnetic bi-wave equations are corresponding with the MAXWELL equations. The metric gμν is a linear functional of an EINSTEIN ian long-range potential gμν and of a subatomic short-range potential definierte Materie-Tensor die gemeinsame Quelle für alle drei Felder ist. Dann ist g1μν, g2μν und gμν und es gelten die Funktional-Bedingungen wobei hier g2μν Feldgleichungen vom “kosmologischen Typ” befriedigt. By these conditions, the short-range interaction becomes a repulsive force and the action of the NEWTON -EINSTEIN ian attraction and of the subatomic repulsion makes the matter point-like (as in the E.-I.-H.-method) but self-consistent. The gravitational metrics g2μν become regulary. P. e., in the EINSTEIN approximation the field of a point-like mass M is given by a SCHWARZSCHILD  相似文献   

9.
Einstein's Hermitian Theory of Relativity as Unification of Gravo- and Chromodynamics Einstein's Hermitian unified field theory is the continuation of the Riemannian GRG to complexe values with a Hermitian fundamental tensor gμv = gv*μ This complexe continuation of GRG implies the possibility of matter and anti matter with a sort of CPT theorem. — Einstein himself has interpreted his theory as a unification and generalization of the Einstein and Maxwell theory, th. i. of gravodynamics and of electrodynamics. However — according the EIH approximation —, from Einstein's equations no Coulomb-like forces between the charges are resulting (INFELD, 1950). But, the forces between two charges ?A and ?B have the form (Treder 1957) It is interesting that such forces are postulated in the classical models of the chromodynamics of the interactions between quarks (for the confinement of their motions. If we interprete the purely imaginary part gμv of the hermitian metrics gμv=gμv+gμv as the dual of the field of gluons then, all peculiarities of Einstein's theory become physically meaningful. — Einstein's own interpretation suggests that the both long-range fields, gravitation and electromagnetism, must be unified in a geometrical field theory. However, the potential α/r + ε/2 has a “longer range” than the Coulomb potential ~1, and such an asymptotical potential ~ ε/2 is resulting from Einstein's equations (TREDER 1957). In Einstein's theory there are no free charges with \documentclass{article}\pagestyle{empty}\begin{document}$ \sum\limits_A^n {\varepsilon A} $\end{document}. (Wyman 1950) because the field mass of a charged particle becomes infinite asymptotically: That means, in a chromodynamics we dont's have free quarks. The same divergence are resulting from one-particle systems with non-vanishing total charges: M~ε2r. However, if the total charges vanish because in a domain ~L3 the positive sources are compensated by negative sources, the field masses of the n-charge systems become finite. From the gravitational part of Einstein's equations we get field masses which are the masses measured by observers in distances r ? L. That means, the masses of quark systems with the colour condition \documentclass{article}\pagestyle{empty}\begin{document}$ \sum\limits_A^n {\varepsilon A} $\end{document} are proportional to the linear dimension L of the system.  相似文献   

10.
Measurements of fluctuations of plasma potential and electron temperature in a toroidal magnetized plasma is carried out by applying a cylindrical probe with insulating end plugs oriented parallel to the B‐field in conjunction with another cylindrical probe oriented perpendicularly. Coherency and cross‐phase between and are estimated, and typically have values close to 0.6 and π respectively. Power‐law spectra are found for frequencies well above the poloidal rotation frequency with spectral index typically around 4.0 for and around 2.5 for . The density gradient is above the threshold for flute interchange instability, and the results are consistent with theory and global numerical simulations of this plasma.  相似文献   

11.
LORENTZ -covariant theories of gravitation which fulfil EINSTEIN 's weak principle of equivalence and which contain a pure Newtonian theory as an approximation are tensortheories with the linear approximative form for the field equations. In the case of EINSTEIN 's strong principle of equivalence the exact field equations must be the general relativistic EINSTEIN -equations (or the bimetrical EINSTEIN -ROSEN -equations). This follows from the dynamical equations and the BIANCHI identity according to JÁNOSSY and TREDER . However, from NEWTON 's axiom of reaction together with the weak principle of equivalence results that the strong principle of equivalence must be valid for the linear approximation of the field equations with sources. Therefore, the linear approximation of all physically meaningful Lorentz-covariant theories of gravitation is given by the linearized EINSTEIN -equations (with HILBERT -conditions): , that is by the ansatz α = 2. The main point of our arguments is LAUE 's postulate of the self-consistency of perfect static systems of isolated gravitational masses. In the lowest order of approximation this self-consistency is only possible if the gravitational matter-tensor is identical with the special-relativistic energy-momentum-tensor Tμv. LAUE 's postulate is fulfilled exactly for the general relativistic field equations according to the theorems of BIRKHOFF , TOLMAN and EINSTEIN and PAULI .  相似文献   

12.
The CERN Intersecting Storage Ring data on the inclusive reaction p + p → π° + X has been fitted with a phenomenological form where Wc(a,b,z) is the generalized confluent function defined by . M(a, b, z) being the well known Kummer's function. Using this form and primary proton spectrum of Goddard Space Flight Center Group the secondary neutral pion-nucleon flux ratio at the top of the atmosphere has been estimated. The derived result has been compared with those expected from p + p → π± + X data, via different models.  相似文献   

13.
The results of first principles electronic structure calculations for the metallic rutile and the insulating monoclinic phase of vanadium dioxide are presented. In addition, the insulating phase is investigated for the first time. The density functional calculations allow for a consistent understanding of all three phases. In the rutile phase metallic conductivity is carried by metal orbitals, which fall into the one‐dimensional band, and the isotropically dispersing bands. Hybridization of both types of bands is weak. In the phase splitting of the band due to metal‐metal dimerization and upshift of the bands due to increased pd overlap lead to an effective separation of both types of bands. Despite incomplete opening of the optical band gap due to the shortcomings of the local density approximation, the metal‐insulator transition can be understood as a Peierls‐like instability of the band in an embedding background of electrons. In the phase, the metal‐insulator transition arises as a combined embedded Peierls‐like and antiferromagnetic instability. The results for VO2 fit into the general scenario of an instability of the rutile‐type transition‐metal dioxides at the beginning of the d series towards dimerization or antiferromagnetic ordering within the characteristic metal chains. This scenario was successfully applied before to MoO2 and NbO2. In the compounds, the and bands can be completely separated, which leads to the observed metal‐insulator transitions.  相似文献   

14.
On Planckian Seconds of the Universe According to the Planckian limites for quantum energies the cosmological scenaria break-down for space dimensions (or for life times of the universe) and for Planckian lengths, not till.  相似文献   

15.
Hg-light absorption at λ = 2537 ǎ by O3 has been used to measure the concentration of O3 in the positive column of an oxygen glow discharge under the nonstationary conditions of the Q-form (tube diameter 3:4 cm). For all gas pressures investigated (p = 7 — 12 torr) the O3 density (n3) as a function of the current reaches a remarkable maximum at i ≈ 15 mA. n3 max was found to increase almost linearly with the gas pressure. At i = 80 mA, on the other hand, n3 increases according to a quadratic relation. In order to understand the dependence of n3 on the pressure and on the current density (or equivalently on the electron density ne) a kinetic model previously developed has been used involving the following particles . For example, it can be shown that in the region of the maximum of n3 one main production process of ozone is the associative detachment reaction . The calculated maximum of the ozone density is higher than the measured one and appears at higher electron density.  相似文献   

16.
Vacuum Light Velocity and Differential Abberation In the frame work of Newton's theories of gravity and of light Laplace (1796) has deduced that the effective velocity c* of light is dependent on the gravitational potential of its source: Laplace, Olbers, a. o. have demonstrated that this effect implies differential aberrations of the light of different cosmisc sources. - But, Einstein's principles of relativity imply the independence of the velocity of light on its sources. This assertion is the fundamental principle of the Einsteinian theories of relativity. However, there seems to be no direct experimental facts disproving Laplace's formula, till today.  相似文献   

17.
Starting from the conventional theory of thermo-field emission of electrons from metal surfaces, the range of validity and the errors of several approximate emission formulae are examined that are additive or harmonic combinations of the limiting thermionic (Richardson) and field emission (Fowler—Nordheim) equations. An optimization of such kinds of equations results in the simple dependence (for example) (iTF electron current density, T temperature, F field strength, k, A, B etc. are constants), or (dependent on only one variable Y = T + β′F β′ = const.). If the emission equations are applied to arc cathodes, both T and F must be expressed as functions of the ion current (Ii) and the ion current density (ji); a simple interpolating formula of the electron current density je adapted to numerical results in the case of Cu cathodes becomes (ā, B?, C?: constants).  相似文献   

18.
This paper is concerned with the hydrostatic equilibrium of a purely gaseous star generating energy at a rate . By the common technique of integration theory of special functions the total net rate of nuclear energy generation is evaluated analytically for a linear density distribution function assumed for a simple stellar model.  相似文献   

19.
The gravity theories of Newton and Einstein are giving opposite sentences about the velocity of light in gravitational field. According to the Newtonian theory the velocity v in gravitational field is greater than the velocity c in a field-free space: v > c. According to general relativity theory we have a smaller velocity: v < c. For a spherical symmetric gravitational field Newton's theory gives \documentclass{article}\pagestyle{empty}\begin{document}$ v \approx c\left({1 + \frac{{fM}}{{c^2 r}}} \right) $\end{document} but Einstein's theory of 1911 gives \documentclass{article}\pagestyle{empty}\begin{document}$ v \approx c\left({1 - \frac{{fM}}{{c^2 r}}} \right) $\end{document} and general relativity gives \documentclass{article}\pagestyle{empty}\begin{document}$ v \approx c\left({1 - 2\frac{{fM}}{{rc^2 }}} \right) $\end{document}. Therefore, the radarecho-measurations of Shapiro are the experimentum crucis for Einstein's against Newton's theory.  相似文献   

20.
G. Koch  H. Happ 《Annalen der Physik》1993,505(6):522-534
The far-infrared reflection spectra of betaine phosphite single crystals in the three crystallographic directions are investigated in the range from 5 to 600 cm?1 at temperatures between 203 and 323 K using a dispersive Fourier spectrometer. The dielectric function is evaluated from the complex amplitude reflection coefficient measured. In the spectrum polarized along the ferroelectric direction a soft mode of relaxation type is observed which accounts for a large part of the relevant static dielectric constant at Tc = 210 K. Among the oscillator modes, which generally exhibit normal temperature dependence, there is a heavily overdamped mode at 58 cm?1, polarized along the crystallographia a1 axis, with anomalous damping behaviour. The damping constant decreases nearly linearly with temperature up to 323 K which is close to T = 355 K where a second phase transition is known to exist.  相似文献   

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