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1.
Let us consider a Lie (super)algebra G spanned by T where T are quantum observables in BV formalism. It is proved that for every tensor c... that determines a homology class of the Lie algebra G the expression c...T...T is again a quantum observable. This theorem is used to construct quantum observables in the BV sigma model. We apply this construction to explain Kontsevich's results about the relation between homology of the Lie algebra of Hamiltonian vector fields and topological invariants of manifolds.  相似文献   

2.
The classical non-linear Schrödinger equation associated with a symmetric Lie algebra =km is known to possess a class of conserved quantities which from a realization of the algebrak []. The construction is now extended to provide a realization of the Kac-Moody algebrak[, –1] (with central extension). One can then define auxiliary quantities to obtain the full algebra [, –1]. This leads to the formal linearization of the system.  相似文献   

3.
The C -extended oscillator algebra is generated by {1, a, a , N, T}, where T is the generator of the cyclic group C of order . It can be realized as a generalized deformed oscillator algebra (GDOA). Its unirreps can thus be easily exhibited using the representation theory of GDOAs and their carrier spaces show a Z-grading structure. Within its infinite-dimensional Fock space representation, this algebra provides a bosonization of parasupersymmetric quantum mechanics of order p = – 1.  相似文献   

4.
The paper solves the problem of gas ionization in a discharge path in a very dilute gas, where the free path of the electrons is much larger than the dimensions of the path and the transit time of the electrons between the electrodes is of the order of the period of the applied h-f voltage. It was found that for a certain ratio of the transit time of the electrons between the electrodes in the discharge path to the period of the h-f oscillation, resonance occurs when the wattless current component is zero. The electron density rises in the path and thus also the gas ionization.
, , , . , , . , .


In conclusion, the author would like to thank F. Benda for preparing the equipment, M. Kivánek for preparing the equipment and some of the measurements, and A. Hrdá for the measurements and for working out the case with equally large a-c and d-c voltages within the framework of her thesis.  相似文献   

5.
The paper gives the values of the optical constants of thin films of germanium obtained by evaporating germanium in a vacuum onto glass slides in the region of 0·35–0·78 for an index of absorptionk and 0·35–2·5 for refractive indexn. The results are compared with the values obtained by other authors and with the values ofn andk for single crystals. It is shown that these values for thin films and single crystals slightly differ quantitatively but agree fairly well qualitatively, which had not been sufficiently the case in previous papers.
, , 0,35 0,78 k 0,35–2,5 n. n, k . , , , , .
  相似文献   

6.
It is possible to define, for any quantum system, an algebra of definite-valued events—those events that are definitely occurrent or non-occurrent. It is shown that two different sets of constraints on the algebra of definite-valued events are each equivalent to the definition of that set as a certain pseudo-Boolean algebra.  相似文献   

7.
We propose an approach to the theory of Lie superalgebras based on what we call a Lie algebra square root. Every Lie algebra square root has a Lie algebra as its square, but many different Lie algebra square roots may have the same square.Invited talk presented at the International Conference Selected Topics in Quantum Field Theory and Mathematical Physics, Bechyn, Czechoslovakia, June 23–27, 1986.  相似文献   

8.
It is proved that for two-particle phenomena theP()2 quantum field theories with speed of lightc converge to non-relativistic quantum mechanics with a function potential in the limitc.Supported by NSF Grant No. PHY 7506746  相似文献   

9.
The critical dynamics of the Syozi model for dilute ferromagnetism is considered by the use of master equations. The dynamics is soluble as it is assumed that the time scale of motion on the sublattice on which the impurities move is so much faster than on the other sublattice that fast relaxing variables may be adiabatically eliminated, leaving a new soluble master equation. It is found that the linear and non-linear relaxation of magnetization exponents (l) and (nl) increase on dilution to (l)/(1–) and (nl)/(1–) respectively ( is the specific heat exponent for the pure system, which itself changes on dilution to –/(1–)). Thus if the exponents for the pure system obey the scaling law of Rácz and Fisher (nl)= (l)– ( is the magnetization exponent which changes on dilution to /(1–)) then so do the exponents for the diluted system. Similarly the exponent for spin diffusion changes on dilution to /(1–).  相似文献   

10.
Zusammenfassung Es wurde der Einfluß eines Bombardements mit Stickstoffionen vor der Erregung untersucht und gezeigt, daß die Stiekstoffatome eine große Rolle bei der Entstehung des Emissionsmaximums bei 150° spielen.
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, 150°C.
  相似文献   

11.
A new quantum group is derived from a nonstandard braid group representation by employing the Faddeev-Reshetikhin-Takhtajan constructive method. The classical limit is not a Lie superalgebra, despite relations like x 2y 2=0. We classify all finite-dimensional irreducible representations of the new Hopf algebra and find only one- and two-dimensional ones.  相似文献   

12.
. . . — - . . . , . , .
Temperature dependence of the young's modulus of the Al-Zn alloys and its influence upon the metastable coherent phase diagram
The paper describes the measurements of the temperature dependence of Young's modulus for several Al-Zn alloys. The moduli were measured by the method of a composite oscillator at resonance frequencies of about 100 kHz. When decreasing the temperature from the state of homogeneous solid solution, the undercooling phenomena cause a hysteresis effect. Young's modulus decreases approximately linearly with increasing atomic fraction of zinc at 390C. The determined temperature and concentration dependence was used for thermodynamic calculation of the form of metastable coherent solubility gaps by which the separation of the solid solution into coherent zones can be described.


B. K. Kardaev, S. P. Nikanorov,A. F. Ioffe Physico-Technical Institute, Acad. Sci. U.S.S.R., Politechnieskaja 26, Leningrad K- 21, U.S.S.R.

J. Laek,Institute of Solid State Physics, Czechosl. Acad. Sci., Cukrovarnická 10, Praha 6, Czechoslovakia.  相似文献   

13.
Levinson's theorem for the one-dimensional Schrödinger equation with asymmetric potential which decays at infinity faster thanx –2 is established by theSturm-Liouville theorem. The critical case where the Schrödinger equation hasa finite zero-energy solution is also analyzed. It is demonstrated that the numberof bound states with even (odd) parityn +(n ) is related to the phase shift + (0)[ (0)] of the scattering states with the same parity at zero momentum as + (0)+ /2 =n + and (0) =n for the noncritical case, and + (0) =n + and (0) – /2 =n for the critical case.  相似文献   

14.
Some concepts of Lie algebra cohomology are used to systematize the search for differential equations invariant under a given Lie groupG. In particular, it is shown that if a strongly invariant equation exists, then all weakly invariant equations differ from it only by an arbitrary multiplicative factor. If no strongly invariant equation exists, then cohomology theory can be used to simplify the search for weakly invariant equations.  相似文献   

15.
We derive the hydrodynamic (Euler) approximation for the harmonic time evolution of infinite classical oscillator system on one-dimensional lattice 1 It is known that equilibrium (i.e., time-invariant attractive) states for this model are translationally invariant Gaussian ones, with the mean 0, which satisfy some linear relations involving the interaction quadratic form. The natural parameter characterizing equilibrium states is the spectral density matrix function (SDMF)F(), [– , ). Time evolution of a space profile of local equilibrium parameters is described by a space-time SDMFF(t;x, ) t, xR 1. The hydrodynamic equation forF(t; x, ) which we derive in this paper means that the normal mode profiles indexed by are moving according to linear laws and are mutually independent. The procedure of deriving the hydrodynamic equation is the following: We fix an initial SDMF profileF(x, ) and a familyP ,>0 of mean 0 states which satisfy the two conditions imposed on the covariance of spins at various lattice points: (a) the covariance at points close to the value –1 x in the stateP is approximately described by the SDMFF(x, ); (b) The covariance (on large distances) decreases with distance quickly enough and uniformly in. Given nonzerotR 1, we consider the states P –1 ,>0, describing the system at the time moments –1 t during its harmonic time evolution. We check that the covariance at lattice points close to –1 x in the state P –1 is approximately described by a SDMFF(t;x, ) and establish the connection betweenF(t; x, ) andF(x,).  相似文献   

16.
A study is made of the influence of successive asymmetrical magnetization reversal on the magnetic state of open samples, where the macroscopic demagnetization field has a significant effect during magnetization reversal and leads to a sort of rotation of the asymmetrical loops performed one after another. This effect is similar to reptation, which was studied experimentally by Nguyen van Dang [1–4] and theoretically explained by Néel [5, 6]. The quantitative expression of the rotation of asymmetrical loops in open samples as a function of the number of loops and amplitude of the disymmetry is similar to that with the reptation effect.
, , . , . .


In conclusion the authors thank Dr. L. Valenta, C. Sc., and Z. Málek, C. Sc., for valuable discussions.  相似文献   

17.
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   

18.
The differential and total cross sections of the processes and 3 are calculated on the basis of the vector-dominance model and current algebra. Up to a photon energy of order 1 GeV, the cross sections of these processes are very small, and it is only in the region of the resonance that values 0.01–0.05 mb are reached.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 9, pp. 84–88, September, 1980.I am very grateful to Professor M. P. Rekalo for constant interest in the work.  相似文献   

19.
Conclusions We have examined the absorption spectra of DS and the dependence of the quantum yield in photodissociation of DC on exciting wavelength, which has shown that the electronic structure of DC allows one to observe *transitions and also n* and * ones, with the a orbital localized on the dissociating C-N bond. The formation of long-lived3(*) excitation leads the DC to dissociation into a neutral nitrogen molecule and an ary1 cation in the triplet state.Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 41, No. 5, pp. 803–809, November, 1984.  相似文献   

20.
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