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1.
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It is shown that if one incorporates the generalized coordinate quantum velocitiesQ 1 as given byQ 1=l[H,Q 1](h=1) into the generalized classical Lagrangian for a free particle (the total energy),L=1/2Q 1 g tk Q k one does not obtain (no matter what ordering of the operatorsq l ,q k andg lkwe choose the correct quantum Lagrangian operator which is a transformation from -1/2V2 to generalized coordinates (Gruber, 1971, 1972).q l as given byq l=i[H,q l] turns out to be the Hermitian part of a more generaiized operator which we call the total generalized velocity operator similar to the notation in ear previous articles (Gruber, 1971, 1972). This total velocity operator really determines the fundamental structure governing our system in the Lagrangian formulation. We show that ft is through the total velocity operator that we make the transition from classical to quantum mechanics and through our procedure we arrive at the correct quantum Lagrangian operator.  相似文献   

3.
A metricg ik=η ik+ iξk+2 (iPk) is investigated. WhenJ=0 this reduces to the well-known Kerr metric. Conditions on the vectorp i are obtained under which a geodetic, shear-free null congruenceξ i in the Minkowskian space-time (with metricη ik) will continue to remain geodetic and shear-free in the Riemannian space-time ofg ik. A general solution of Einstein’s equationR ik=σξ iξk is obtained whenp iξi=0 andξ i is twist-free.  相似文献   

4.
Using the Mössbauer technique electric hyperfine interactions of the first excited non-rotational states at 64 keV in157Gd and at 86.5 keV in155Gd have been determined in GdF3 and GdCl3· 6H2O. For the ratio of quadrupolmoments the ratiosQ 64 157 /Q g 157 =1.74±0.04,Q 86.5 155 /Q g 157 =?0.07 ± 0.21 andQ g 155 /Q g 157 =0.78 ± 0.06 were found. In addition isomer shifts were observed from which a ratio δ〈r2 64 157 /δ〈r2 86.5 155 =?2.6±0.15 can be inferred.  相似文献   

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A quantum nonlinear Schrödinger model with supermatrices and attractive coupling is studied by using the quantum inverse scattering method. The eigenstates of the Hamiltonian and the infinite number of the conserved quantities of the system are constructed. In particular, theN-particle bound states with the mixture of bosons and fermions are found. The energy of theN-particle eigenstate are Σ i=1 N andNp 2 ?N(N 2?1)c 2/12 for the scattering state and the bound state respectively.  相似文献   

7.
Investigations of the rotational band based on the 3+ 3 two quasiparticle state in172Yb have shown that some of its properties can be well described by the collective model of Bohr and Mottelson. As a result of these investigations we have derived the ratio (g k – g R )/Q o =? (0.0136 ± 0.0007). The magneticg-factor of the band head has also been determined by an integral angular correlation measurement perturbed by an external magnetic field. As a result we foundg=0.201 ± 0.030. Using this value and our result of (g k – g R )/Q o we have calculated theg R -factor of the two quasiparticle state asg R =0.283 ± 0.018 which is out of the errors smaller than theg R -factor of the ground state rotational band. An analysis of our angular correlation experiments gave for the mixing parameter δ of theK-forbidden 1094 keV intraband transition: δ=? (3.63 ?0.06 +0.14 ) in agreement with the results of other authors.  相似文献   

8.
The energy-density components Θ 0 0 andT 0 0 of the canonical and of the metrical energy-momentum tensors Θ k i andT k i for a statical field of vector mesons have opposite signatures: Θ 0 0 =H=?T 0 0 =?L. From this property some relativistic and field-theoretical theorems can be deduced in an elementary way.  相似文献   

9.
The absorption spectrum of antiferromagnetic dysprosium aluminium garnet (DAG) (T N =2.50 °K) has been investigated at low temperatures. The groundstate splitting due to all interactions in the antiferromagnetic state is (5.27±0.10) cm?1 extrapolated to 0 °K. The temperature dependence of the lineshift of the absorption lines is measured. Zeeman effect studies give theg-tensor of the groundstate asg z =18.4±0.5,g x =g y =0.5±0.2. The studies also allow the determination of the critical fields asH c [100] =(5.0±0.1) koe,H c [111] =(3.9±0.2) koe andH c [110] =(4.9±0.6) koe. In addition an investigation of a number of satellite lines is performed. Some of them can be interpreted as spin wave sidebands (Stokes and anti-Stokes); others obviously come from dysprosium ions which have impurity ions on regular lattice sites as neighbours.  相似文献   

10.
The quantum GrassmanianG(2|0; ? q 4|0 ) of “quantum 2-planes ? q 2|0 in the quantum 4-plane ? q 4|0 ”, which provides aq-deformation of compactified complexified Minkowski space, is proposed. A quantum analogue of classical Plücker embedding of the usual GrassmanianG(2; ?2) into a non-degenerate quadric in ??5 is found.  相似文献   

11.
The total potential energy of a crystal U({r ik }) as a function of the vectors r ik connecting centers of equilibrium positions of the ith and kth atoms is assumed to be represented as a sum of irreducible interaction energies in clusters containing pairs, triples, and quadruples of atoms located in sites of the crystal lattice A2: U({r ik }) ≡ Σ N=1 4 E N ({r ik }). The curly brackets denote the “entire set.” A complete set of invariants {I j ({r ik })} N , which determine the energy of each individual cluster as a function of the vectors connecting centers of equilibrium positions of atoms in the cluster E N ({r ik }) ≡ E N ({I j ({r ik })} N ), is obtained from symmetry considerations. The vectors r ik are represented in the form of an expansion in the basis of the Bravais lattice. This makes it possible to represent the invariants {I j ({r ik })} N in the form of polynomials of integers multiplied by τ 2 m . Here, τ2 is one-half of the edge of the unit cell in the A2 structure and m is a constant determined by the model of interaction energy in pairs, triples, and quadruples of atoms. The model interaction potential between atoms in the form of a sum of the Lennard-Jones interaction potential and similarly constructed interaction potentials of triples and quadruples of atoms is considered as an example. Within this model, analytical expressions for second-order and third-order elastic moduli of crystals with the A2 structure are obtained.  相似文献   

12.
The electric quadrupole interaction constantB of the 8p2P3/2 state of Cs134 has been determined by an optical double resonance measurement of the hyperfine structure transition vF=11/2?F=9/2=47.84(12) Mc/s. The results are: B 8P 134 =8.06(20) Mc/s and Q 8P 134 =+ 0.427(8) · 10?24cm2. Comparison is made between the measurements in the 7p and 8p electronic states: Q 8P 134 /Q 7P 134 =0.977(20). The ratio of the corresponding Sternheimer correction factors yields the value C7p/C8P=0.982.  相似文献   

13.
The hyperfine structure splitting of the 72 P 3/2 state of Rb85 and Rb87 has been measured with optical double resonance. The following hfs interaction constants have been obtained: Rb85:A 7p 85 =3.71(1) MHz;B 7p 85 =3.68 (8)MHz. Rb87:A 7p 87 =12.57(1) MHz;B 7p 87 =1.71 (3)MHz. These values yield quadrupole moments ofQ 7p,hfs 85 =+0.316(7) barn andQ 7p,hfs 87 =+0.147(2)barn which are reduced by application of the Sternheimer correction toQ 7p 85 =+0.267(6) barn andQ 7p 87 =+0.124(2) barn. The averaged ratio of the uncorrected values of Qhfs in the 5p and 7p 2 P 3/2 stake isQ 5p,hfs/Q 7p,hfs=1.07(3). This has to be compared with the correction factors for polarization of the core of electrons by the nuclear quadrupole moment (1?R)5p/(1?R)7p=1.07. The agreement between the measured and calculated ratio indicates a net antishielding of the nuclear quadrupole moments of rubidium by the core of electrons as has been predicted bySternheimer. The lifetime of the 72 P 3/2 state of the RbI-spectrum is:τ(72 P 3/2, Rb)=2.4(2)·10?7 sec.  相似文献   

14.
A quantized space-time metricg ik (x) is investigated within a suitably modified axiomatic approach. Coordinate distancesdx are called absolutely space-like ifg ik (x)dx i dx k is negative definite. For such distances, fields are assumed to commute or anticommute, respectively (generalized locality). The quantum fluctuations of the light coneg ik (x)dx i dx k =0 are shown to extend to distancesdx which are space-like with respect to the Minkowski metric. Generalized locality is therefore weaker than the usual locality postulate.Supported in part by the Deutsche Forschungsgemeinschaft.  相似文献   

15.
The electron capture decays of133Ba (10.4 y) and139Ce (140 d) were investigated with high resolution Ge(Li) detectors. By x-ray — γ-ray coincidences values of the quantityP k ω k ? k for various transitions in the decay of133Ba and139Ce are obtained. The factor ω k ? k was measured independently by means ofK-conversion electron-K x-ray coincidences and was then used to determineP k , theK-capture probability. The independent measurement of the product ω k ? k , together with recent accurate values of ω k , provides a new method for the accurate calibration of semiconductor x-ray detectors. In the decay of139Ce, a value ofP k =0.78±0.03 is found (where the error represents twice the standard deviation) from whichQ ec =326 ?30 +70 keV to the139La ground-state is found by use of theory. In133Ba decay, values are found ofP k 1=0.72±0.04 for theEC transition to the 437 keV level in133Cs,P k 2=0.80±0.07 to the 384 keV level, and from an independent measurement, the ratioP k 1/P k 2=0.87±0.07. From these results the ground-state value ofQ ec =522 ?10 +20 keV is derived from theory for133Ba decay. The gamma spectrum of133Ba also was remeasured. From the present gamma intensities and previous conversion electron intensities, new values forK-shell conversion coefficients are obtained. Previously reported γ-rays at 35 and 391 keV are not confirmed.  相似文献   

16.
17.
A new approach to constructing the various generalizations of the one-dimensional supersymmetric quantum mechanics is proposed, including the parasupersymmetric quantum mechanics constructed by Rubakov and Spiridonov as the special case. In particular, we derive the generalized superalgebra, which possesses the features both of the familiar superalgebra and of the parasuperalgebra. Namely, the generalized supercharges Qi ± and the Hamiltonian H forms the generalized superalgebra, where Qi ±2=0 (as for ordinary superalgebra), but the triple products of generalized supercharges obey the relations Q1 +Qj Qj +=Qi +H (i, j=1, 2) and Qi +Qi Qj +=(1/4)kQi +, Qi +Qi Qj +=(1/4)kQi +(i, j=1, 2; ij) (analogous to the parasuperalgebra). Furthermore, the generalized supercharges are conserved, i.e. [H, Qi ±]=0.Presented at the International Workshop on Squeezed and Correlated States, Moscow, December 3–7, 1990.  相似文献   

18.
TheK-electron capture probabilities (P k) for the 58 keV state and the ground state of159Tb in the decay of159Dy have been determined. The measured values,P k 58 =0.81±0.05 andP k 0 =0.79±0.06 are found to be in excellent agreement with theoretical results.  相似文献   

19.
The purpose of this paper is to study the so-calledspectral class Q of anharmonic oscillatorsQ=?D 2+q having the same spectrum λ n =2n (n≧0) as the harmonic oscillatorQ 0=?D 2+x 2?1. Thenorming constants \(t_n = \mathop {\lim }\limits_{x \uparrow \infty } \ell g[( - 1)^n {{e_n (x)} \mathord{\left/ {\vphantom {{e_n (x)} {e_n }}} \right. \kern-0em} {e_n }}( - x)]\) of the eigenfunctions ofQ form a complete set of coordinates inQ in terms of which the potential may be expressed asq=x 2?1?2D 2 ?g? with $$\theta = \det \left[ {\delta _{ij} + (e^{ti} - 1)\int\limits_x^\infty {e_i^0 e_j^0 :0 \leqq i,j,< \infty } } \right],$$ e n 0 being then th eigenfunctionQ 0. The spectrum and norming constants are canonically conjugate relative to the bracket [F, G]=∫ΔFDΔGdx,to wit: [λ i , λj=0, [t i, 2λ j ]=1 or 0 according to whetheri=j or not, and [t i,t j]=0. This prompts an investigation of the symplectic geometry ofQ. The function ? is related to the theta function of a singular algebraic curve. Numerical results are also presented.  相似文献   

20.
The first moment of the polarized parton distributions of the proton is evaluated dynamically using the assumption that at some low resolution scale the proton consists of valence quarks only. The spin carried by gluons, ΔG, at the EMC resolution scaleQ 0 2 =10 GeV2 ispredicted to be ΔG/s p ?5 withs p=1/2 denoting the spin of the proton. This result furthermoreexplains the dynamical origin of the recent EMC measurement of the first moment of the polarized structure functiong 1 P (x, Q 2).  相似文献   

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