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1.
The tensor product of two supersingleton representations n of the Lie superalgebraosp (1, 2n) is studied forn2. The main results are as follows: (a) anticommutators and commutators of the odd generators in n n form a skew-symmetric representation of the Lie algebrau(n, n); (b) simple explicit form of all irreducible components of n n, which are labelled by a single parameterJ=0, 1, ..., has been found. Each of them is a*-representation ofosp (1, 2n) for which assertion (a) is valid. The dimension of its vacuum subspace equals , i.e., the nondegenerate vacuum occurs for J=0 only. Basic property of this family of irreducible*-representations of osp(1, 2n) are analogous to those of massless representations of osp(1, 4).Dedicated to Academician Václav Votruba on the occasion of his eightieth birthday.  相似文献   

2.
We present exact explicit expressions for the row spin-spin correlation functions 00 n0 in the isotropicd= 2 Ising model, in terms of elliptic integrals, forn 5. We also give a general structural formula for 00 n0.  相似文献   

3.
Every normal, faithful, self-adjoint functional on a von Neumann algebraA canonically determines a one-parameter-weakly continuous *-automorphism group (the analog of the modular group) and a canonical 2 grading onA, commuting with . We show that the functional satisfies the weak super-KMS property with respect to and Furthermore, we prove that and are the unique pair of a-weakly continuous one-parameter *-automorphism group and a grading of the algebra, commuting with each other, with respect to which is weakly super-KMS. The above results thus provide a complete extension of the theory of Tomita and Takesaki to the nonpositive case.Supported in part by the National Science Foundation under Grant DMS-8922002.  相似文献   

4.
We employ QCD sum rules to calculate the coupling constant g by studying the three point -correlation function. Our result complements the analysis of this coupling constant utilizing the experimental value of the 00 decay rate studied within the framework of chiral perturbation theory including vector meson and meson intermediate states.  相似文献   

5.
The effects of surfaces on percolation are investigated near the bulk percolation threshold ind=6– dimensions. Using field-theoretic methods, this is done within the framework of a semi-infinite continuousq-state Potts model withq1. Renormalization-group equations are obtained which imply that the usual scaling laws for surface and bulk exponents are valid to all orders in , and the surface exponents at the ordinary and special transition are computed to order . Our result for 1 ord is in conformity with the one by Carton.  相似文献   

6.
We define a covariant and gauge-invariant generalization of the Wigner functions of particles with spins 1/2 and 0. The collisionless kinetic equations are obtained for these particles in external gravitational and electromagnetic fields in the quasiclassical approximation; also obtained are the momentum representations of the energy-momentum tensor, current, and spin tensor, taking into account the effects of the spin's interaction with the gravitational field an electromagnetic field. The following notation is used: e and m are the charge and mass of the particles; is Planck's constant; (x) are the covariant-fixed Dirac matrices; ,=(1/4)[, ]: a(b)=(1/2) (a b +ab ); [A, B]=A·B – B·A; A,B=A·B+B·A; g(x)=det(g (x));R = –...; the speed of light c=1.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 9, pp. 47–53, September, 1990.The author wishes the thank Yu. G. Ignat'ev and members of the seminar in General Relativistic Statistics and Cosmology of the Kazan' Pedagogical Institute for useful discussions.  相似文献   

7.
8.
E=mc 2 is found to be a special case ofE= ±1cn, where is any one of four susceptibilities, namely electric, magnetic, gravitational, and elastic. Letl be length,t time,t time dilation, andl a measure of Fitzgerald-Lorentz contraction. A particle is stated to be the manifestation of a collection of susceptibilities which arise when(l)/1=(t)/t. Then(E)/E=5 (t)/2t=±()/. Corresponding to susceptibility, special energy particles are postulated which exhibitSU(3) symmetry, Related to the susceptibilities are five new Heisenberg uncertainty relations. Three new conservation laws for particles are proposed.  相似文献   

9.
[1] t B , t B . , t B , . .
A note on the theory of the successive production of moving striations in the plasma of inert gases
Approximate expressions are derived on the basis of Pekárek's theoretical paper [1] for the period of the maximum tB of a wave packet produced by the passage of a wave of stratification before the aperture of a photomultiplier, and for its time width in the half-height tB. The relaxation time of a wave of stratification, following from the theory [1], can thus be calculated by means of the experimentally measured velocity of motion of the maximum of a wave packet u and its width tB. The calculation is supplemented by numerical data on the magnitude of errors committed by using approximate expressions.
  相似文献   

10.
11.
12.
We give an explicit L 2-representation of chiral charged fermions using the Hardy–Lebesgue octant decomposition. In the pure case such a representation has already been used by M. Sato in holonomic field theory. We study both pure and mixed cases. In the compact case, we rigorously define unsmeared chiral charged fermion operators inside the unit circle. Using chiral fermions, we orient our findings towards a functional analytic study of vertex algebras as one-dimensional quantum field theory.  相似文献   

13.
The losses caused by bremsstahlung during electron-ion and electron-electron collisions in a completely ionized plasma (in Born's approximation) are calculated. The calculation can be carried out analytically for a sufficiently dilute plasma (plasma with infinitely large Debay-Hückel radius). This assumption is satisfied very well by the known classification to actual controlled thermonuclear reaction. A dependence of the formI=an 2. (1+3/2), wherea=0·73×10–16 MeV.cm3.sec–1,n is the number of ions per cm3 and =kT/mc 2, is determined for the amount of energy radiated from 1 cm3 of plasma per sec. In the relativistic temperature regionkTmc 2 the influence of electron-electron collisions begins to predominate. A number of important results concerning radiation losses in relativistic plasma will be published in a later paper.
, ( ). ( -). . , I=an 2. (1+3/2), =0,73. 10–16 MeVcm2s–1,n — =kT/mc 2. kTmc 2 . , .
  相似文献   

14.
The possible ways of drawing of the intensity of the S0 T* transition in the chlorobenzene molecule are investigated. The effective spin-orbit coupling of either S* or S* states with the T* state leads to the out-of-plane polarized component of phosphorescence in the chlorobenzene. The in-plane polarized component cannot be explained by the mechanism under consideration — by drawing of intensity of the S0 S0* transitions through spin-orbit coupling of first order.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 8, pp. 134–138, August, 1974.  相似文献   

15.
The neutron density in the vicinity of a black cylindrical rod partly inserted in a bare reactor is calculated and illustrated by a numerical example. The starting point is a two-group diffusion theory approximation. While the dependence of the effect of the rod on the insertion depth can be calculated simply by means of perturbation theory, the question of the neutron density estimate in the vicinity of the rod is considerably more difficult and in some considerations the estimate of the neutron density caused by the presence of the rod is indispensable. The method makes it possible to determine the reactivity value of the rod in dependence on the insertion depth and especially the neutron density deformation in the vicinity of the rod.
()
. , . , , . , . [1] . .


In conclusion the author thanks J. Svato for help in carrying out the numerical calculations.  相似文献   

16.
The differences in decay rates of the nuclear isomer119mSn (T1/2=293 days; the strongly converted M4 transition) have been measured for different chemical compounds. The experimental results show that the119mSn nuclei in the telluride SnTe decay faster then in the metal -Sn and in the dioxide SnO2 [the relative change / of the decay probability is +(3.6±1.4)·10–4]. No measurable difference between the decay rates of119mSn in -Sn and SnO2 has been observed [(/=–(0.1±1.2)·10–4], irrespective of the great difference in electronic structure of the tin atoms. The results cannot be explained by considering the internal conversion of the valence electrons only. It is necessary to assume that the chemical changes of the decay rate are strongly influenced by the chemical changes of the probabilities of the internal conversion of electrons of the inner shells of the atom. This conclusion is confirmed by theoretical calculations. They show that for the deep inner subshells the relative changes nlj/nlj of the internal conversion coefficients nlj are much greater than the relative changes nlj/nlj of the electron densities near the nucleus nlj.  相似文献   

17.
Extra integrals of motion and the Lax representation are found for interacting spin systems with the HamiltonianH = (J/2) j, k=1,j k N P(j – k) j k , where one of the periods of the WeierstrassP function is equal toN. The Heisenberg and Haldane-Shastry chains appear as limiting cases of these systems at some values of the second period. The simplest eigenvectors and eigenvalues ofH corresponding to the scattering of two spin waves are presented explicitly for these finite-dimensional systems and for their infinite-dimensional version.  相似文献   

18.
We derive the exact matrix field theory for a replicated grassmannian representation of a local pairing superconducting disorder ensemble including three superconducting order parameters and the spin-flip pairbreaking mechanism. Disorder is assumed to be gaussian distributed. We find by exactly solving the saddle-point equation the criterion for a vanishing gap –1 + –1 , where denotes the averaged superconducting order parameter, –1 the spin-flip scattering rate, and –1 the scattering rate corresponding to correlations of Re(–). Taken at =0, our field theory, which is exact in all orders of –1 , contains new terms in addition to those of theO( –1 ) model derived by Efetov et al. Our formulation transfers correctly to all orders the invariances of the action into symmetries of the matrix field theory. The saddle point approximation is outlined and it is shown how singular corrections to the saddle point density of states arise atE F in a gapless superconductor. Finally singular corrections in the two particle propagator, the density correlation function and the conductivity are calculated for =0 in one loop order. It turns out that these corrections can be entirely expressed by those of the single particle density of states.  相似文献   

19.
Difficulties in the interpretation of high-energy nuclear interactions are discussed and explanations suggested on the basis of successive or composite nucleon-nucleus collisions, the first predominant below a few 10 11 eV,the second for higher energies. In the energy region up to about 10 11 eVsome discrepancies in the frequency of production of strange particles, the small interaction cross-section of iron etc. are explained, taking into account secondary intranuclear collisions. The tunnel model of Heitler and McCusker is replaced by assuming a cone-shaped interaction volume (funnel) even at the highest primary energies. A number of consequences concerning the energies of the primary particles, the multiplicity and asymmetry in the angular distribution of secondaries, coefficient of inelasticity etc. are discussed.
, , 1011 eV, — . 1011 eV , ., , . () . , , , .


This paper contains a condensed summary of some of the material presented in a series of lectures given by the author on the occasion of his visit to Prague in December 1957/January 1958. Its publication in this form is intended as an expression of thanks to the Czechoslovak Academy of Sciences and its leading Officers, in particular Prof. V. Procházka, Prof. J. Novák, and Prof. V. Petrílka, whose kind invitation made this visit possible.  相似文献   

20.
The paper gives the results of measuring the temperature dependence of the electrical conductivity(T), the Hall coefficientR H (T) and the magnetic susceptibility(T) forn-type CdSnAs2. The effective mass of the electrons was determined by analysis of the measured dependences on the basis of the simple theory for an isotropic non-degenerate semi-conductor. It was found to bem n /m 0=2×10–2 in the intrinsic region and does not depend on the temperature; the energy gap ise g 0=0·26 eV and the molar susceptibility of the CdSnAs2 lattice G mol=–112× ×10–6. The mobility of the electrons in the intrinsic region reaches a value of n =25 000 cm2V–1sec–1 at 500°K and decreases exponentially n T –1.67 with rising temperature. The density of CdSnAs2 was determined pyknometrically,g9=5·35 g cm–3. The measurements were made on ann-type polycrystalline sample consisting of crystals a few millimetres in diameter, which at a temperature of 100°K had a free electron concentration ofn s =6×1016 cm–3.
CdSnAs2
(T), R H (T) (T) CdSnAs2 . m n /m 0= =2.10–2, ; E G 0=0,26 eV, CdSnAs2 G mol= =–112.10–6. 500°K n =25 000 cm2V–1sec–1 , n T –1,67. CdSnAs2 =5,35 g cm–3. , , 100°K n s =6.1016cm–3.


The authors would like to thank Mr. P. Jansa for help in measuring the temperature dependence of the magnetic susceptibility.  相似文献   

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