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1.
We present a regular class of exact black hole solutions of the Einstein equations coupled with a nonlinear electrodynamics source. For weak fields the nonlinear electrodynamics becomes the Maxwell theory, and asymptotically the solutions behave as the Reissner–Nordström one. The class is endowed with four parameters, which can be thought of as the mass m, charge q, and a sort of dipole and quadrupole moments and , respectively. For 3, 4, and |q|2s c m the corresponding solutions are regular charged black holes. For = 3, they also satisfy the weak energy condition. For = = 0 we recover the Reissner–Nordström singular solution and for = 3, = 4 the family includes a previous regular black hole reported by the authors.  相似文献   

2.
Zusammenfassung In der vorliegenden Arbeit werden einige Ergebnisse, die an ferromagnetischen Proben erhalten wurden, beschrieben. Verwendet wurde Kupferdraht, auf welchen Nickelschichten von verschiedener Dicke niedergeschlagen wurden. Die Proben zeigen, daß dabei die innere Reibung im magnetischen Wechselfeld unter den Wert, der der magnetischen Sättigung entspricht, fallen kann, und daß am Torsionspendel unter bestimmten Umständen erzwungene Schwingungen entstehen.
, . , . , , , .
  相似文献   

3.
We consider a quantum mechanical model which displays the behaviour associated with having a resonance or metastable state. The Hamiltonian depends on a parameter . When =0, there is an eigenstate 0; when 0, 0 dissolves into the continuous spectrum, showing approximate exponential decay. We prove this result without using dilatation analyticity. The model describes a two-state atom coupled to the quantized radiation field. The state space of the field is truncated, so that only the vacuum and one-photon states are included.This work was partially supported by NSF Grant DMS-8922941  相似文献   

4.
The structure function S(k; ) for the one-dimensional one-component log–gas is the Fourier transform of the charge–charge, or equivalently the density–density, correlation function. We show that for |k|j in the power series expansion of f(k; ) about k=0 is of the form of a polynomial in /2 of degree j divided by (/2)j. The bulk of the paper is concerned with calculating these polynomials explicitly up to and including those of degree 9. It is remarked that the small k expansion of S(k; ) for the two-dimensional one-component plasma shares some properties in common with those of the one-dimensional one-component log–gas, but these break down at order k8.  相似文献   

5.
The C6H5X compounds are considered as regards the energy and wave function x as functions of within limits of –3 and +3, and also as functions of cx within limits of 0. 5 and 1. 5. Convenient numerical tables are compiled.We are indebted to N.A. Prilezhaev and V.I. Danilov for extensive collaboration in this work.  相似文献   

6.
In terms of Bogoliubov's nonlinear theory, the first five betatron-synchrotron resonances of s=(p q)2K, p/q=1/2, 1, 3/2, 1/3, 2/3 which may occur during laser satulation establishing process have been generally examined. Contrast to previous studies we found that the most dangerous resonance does not take place in the vicinity of s=2k, but in that of s=k. The width of region of s=k is proportional to with (k w 2 /k) remittance, the passing time over the region due to the laser field being amplified is only one pass over the undulator at most and depends on the gain, and the increment of synchrotron amplitude in passing time is proportional to .In summary we conclude that the betatron-synchrotron resonances do not have any significant effect for detrapping off-axis electrons in a practical case.  相似文献   

7.
Calculations have been performed on the integral shapes of the K lines, which are long-wave satellites of the K 1 lines, for Cl, Ti, and Fe, where allowance has been made for interference between states in the 2p–1 and 3p–2p configurations. The calculations show that these satellites represent short-wave branches of the K lines strengthened by the 3p-1s transition with simultaneous M electron ejection. The strong interference between the amplitudes of these processes in the final state means that it is in principle quite impossible to speak of the intensities of the K satellites without stating how they are isolated from the measured spectrum.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 9, pp. 34–39, September, 1984.  相似文献   

8.
We establish a new three-mode entangled state representation , of continuum variables, which make up a complete set. Using optical four-wave mixing and a beam splitter transform we can prepare , . Based on , a new number-difference--operational-phase uncertainty relation is established and the corresponding squeezing dynamics is discussed.  相似文献   

9.
A systems analysis of the interaction between objects (tumor, healthy tissue, radiation, and photosensitizer of the singlet state of oxygen) involved in photodynamic therapy was carried out. A schematic diagram of the biologically significative processes proceeding under these circumstances was proposed. This schematic diagram can serve as a basis for a systems approach to the optimization of photodynamic therapy. The efficiency of the systems approach in photodynamic therapy was demonstrated using Fotosens and Khlorin S preparations, carotene, and dodecaprene -carotene in biological experiments on Wistar rats and mouses inoculated for the solid sarcoma M-1.  相似文献   

10.
We have found that gamma-irradiated polyformaldehyde does not exhibit the effect of the disappearance of the hyperfine structure of EPR spectrum as a function of the dose or the time passed since the end of irradiation, as was found earlier for a group of polymers having only C-C-C-C-atoms in the polymer chain. This difference in the change in the EPR of the polyformaldehyde (PFA) spectrum compared with the polymers with a -C-C-C-C- chain is explained by the impossibility of forming a conjugate double bond in the -C-O-C-O- chain in PFA.
, , -, , , atom C-C-C-C-. ( ) C-C-C-C- , C-O-C-O- qu .


The author thanks K. Vacek for many valuable discussions which helped this work.  相似文献   

11.
We show that Ruelle's generalised -function for a classical one-dimensional lattice spin system with two-body interaction (i) exp(-i )a(i) with >1 extends to a meromorphic function in the whole complex plane.  相似文献   

12.
A cluster of two atoms described by thes-f model with Coulomb repulsion has been considered. The interaction between localized 4f electrons (S=1/2) is taken in the molecular field approximation. The thermodynamic quantities like magnetization, specific heat and correlation functions n , n , S z n , S z n , S z (n n ), n n and S + a + a as functions of temperature are presented for different band fillingN=0, 0.5, 1, 1.5, 2. The dependence of Curie temperature onN is calculated. The phase diagram forN=1 (T=0K) shows the possibility of existence of two phases: paramagnetic and ferromagnetic.The Curie temperature and the specific heat as functions ofN exhibit similar trends as found in experiments on doped magnetic semiconductors.  相似文献   

13.
Four classes of solutions are found to the equations R=–2; ; and g ;=0 in three-dimensional space with metric gdxdx and signature (+ ––), equivalent to the Einstein equations Rij=0 in a vacuum for the metric . The metric ds2 assumes axial symmetry and symmetry with respect to the reflection .Translated from Izvestiya Uchebnykh Zavedenii, Fizika, No. 9, pp. 43–45, September, 1976.  相似文献   

14.
Any automorphism of the Dynkin diagram of a symmetrizable Kac-Moody algebra g induces an automorphism of g and a mapping between highest weight modules of g. For a large class of such Dynkin diagram automorphisms, we can describe various aspects of these maps in terms of another Kac-Moody algebra, the orbit Lie algebra . In particular, the generating function for the trace of over weight spaces, which we call the twining character of g (with respect to the automorphism), is equal to a character of . The orbit Lie algebras of untwisted affine Lie algebras turn out to be closely related to the fixed point theories that have been introduced in conformal field theory. Orbit Lie algebras and twining characters constitute a crucial step towards solving the fixed point resolution problem in conformal field theory.  相似文献   

15.
Lucifer yellow and lissamine rhodamine sulfonyl hydrazine were used as the donor and the receptor, respectively, for Förster energy transfer measurements to determine the location of the subunit in the native Na,K-ATPase from pig kidney. It was found that (1) the subunits are located in one functional complex, i.e., the dimer ()2 appears to be the functional complex of Na,K-ATPase, and (2) the subunits in the functional enzyme complex in the membrane are not located next to each other but are rather well separated. The distance between fluorophores covalently attached to the subunits was found to be 5.3 nm.  相似文献   

16.
Results from percolation theory are used to study phase transitions in one-dimensional Ising andq-state Potts models with couplings of the asymptotic formJ x,y const/¦xy¦2. For translation-invariant systems with well-defined lim x x 2 J x =J + (possibly 0 or ) we establish: (1) There is no long-range order at inverse temperatures withJ +1. (2) IfJ +>q, then by sufficiently increasingJ 1 the spontaneous magnetizationM is made positive. (3) In models with 0<J +< the magnetization is discontinuous at the transition point (as originally predicted by Thouless), and obeysM( c )1/( c J +)1/2. (4) For Ising (q=2) models withJ +<, it is noted that the correlation function decays as xy()c()/|xy|2 whenever< c . Points 1–3 are deduced from previous percolation results by utilizing the Fortuin-Kasteleyn representation, which also yields other results of independent interest relating Potts models with different values ofq.  相似文献   

17.
We consider an exclusion process with particles injected with rate at the origin and removed with rate at the right boundary of a one-dimensional chain of sites. The particles are allowed to hop onto unoccupied sites, to the right only. For the special case of = = 1 the model was solved previously by Derridaet al. Here we extend the solution to general , . The phase diagram obtained from our exact solution differs from the one predicted by the mean-field approximation.  相似文献   

18.
We show that a lower large-deviation bound for the block-spin magnetization in the 2D Ising model can be pushed all the way forward toward its correct Wulff value for all >c.  相似文献   

19.
A classical gas with short-range interaction in the grand canonical ensemble is studied. Ifp(, z) denotes the thermodynamic pressure at inverse temperature and activityz, then it follows from the Mayer expansion thatp(, z) is infinitely differentiable provided andz are sufficiently small. Here it is shown that there exists 0>0 such thatp(, z) is infinitely differentiable if< 0 andz>0. One can interpret this result as saying that ( 0)–1 is an upper bound on the critical temperature for the system.  相似文献   

20.
For a family of translation-invariant, ferromagnetic, one-component spin systems—which includes Ising and 4 models—we prove that (i) the phase transition is sharp in the sense that at zero magnetic field the high- and low-temperature phases extend up to a common critical point, and (ii) the critical exponent obeys the mean field bound 1/2. The present derivation of these nonperturbative statements is not restricted to regular systems, and is based on a new differential inequality whose Ising model version isMh+M 3+ M 2M/. The significance of the inequality was recognized in a recent work on related problems for percolation models, while the inequality itself is related to previous results, by a number of authors, on ferromagnetic and percolation models.  相似文献   

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