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1.
I. L. Zhogin 《Russian Physics Journal》1991,34(2):105-110
Field equations for n-frames h
a
that are possible in the theory of absolute parallelism are considered. It is shown that in three cases the equations can, after the substitution h
a
=HpH
a
(H=det H
a
, p is an n-dependent constant), be written in a trilinear form that contains only the matrix H
a
and its derivatives and not H
a
. It is shown that the equations are still regular for degenerate but finite matrices H
a
if rank H
a
2.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 2, pp. 22–27, February, 1991. 相似文献
2.
O. A. Fonarev 《Russian Physics Journal》1990,33(9):759-764
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
3.
Zero field SR spectra from Cr85Mo15 are well described by the sum of a lightly damped (0.02s–1<1<0.2s–1) and a heavily damped (2s–1<2<15s–1) exponential. The temperature dependence of these components is discussed in relation to the condensation of the incommensurate spin density wave and the onset of the antiferromagnetic state in this Cr-like alloy below TN=120K. Evidence is presented for the nucleation of the spin density wave at temperatures greater than 1.5TN. 相似文献
4.
P. Strasser K. Ishida S. Sakamoto M. Iwasaki E. Torikai K. Nagamine G. M. Marshall 《Hyperfine Interactions》1993,82(1-4):543-549
Slow – production via dd-CF using a two-layer arrangement is investigated. To determine its feasibility, experimental measurements are now in progress using the muonic X-ray detection method. The following experimental steps are being considered: (1) measurement of the number of – stopped inside a solid H2/D2 layer by detecting p K X-rays, (2) hot d emission detection by placing a secondary target at a distance of 10–30 mm from the layer and by detecting specific delayed X-rays, (3) measurement of the disappearance of d emission as the added D2 layer is increased, (4) dd-CF measurement by detecting fusion protons, and (5) slow – emission detection. Results of the initial test experiment are presented. 相似文献
5.
N. A. Nemkovich W. Baumann V. G. Pivovarenko A. N. Rubinov 《Journal of Applied Spectroscopy》2003,70(2):230-237
The dipole moments in the equilibrium ground (
g) and excited Franck–Condon states (
e
FC) of the molecules of 4-(methoxy)-3-hydroxyflavone (FOM), 4-(dimethylamino)-3-hydroxyflavone (FME), and 4-N-(15-azacrown-5(-3-hydroxyflavone (FCR) in 1,4-dioxane were measured. Characteristic of these probes is excited-state intramolecular proton transfer. For comparison, the dipole moments of the molecules of 4-(dimethylamino)-3-methoxyflavone (FME3ME) were measured, for which the excited-state intramolecular proton transfer is lacking. It is established that in the case of FME, FCR, and FME3ME the dipole moments
g and
e
FC are parallel to the absorption transition dipole moment m
a responsible for absorption. Among the compounds studied, FOM has the least values of
g and
e
FC, only 9.4·10–30 and 26.3·10–30 C·m, respectively. The dipole moments
g,
e
FC and m
a are not parallel to one another, and the angles between them lie in the range 4–55°. This effect is due to FOM not having a strong electron-donating group, such as an amino group. 相似文献
6.
Kazimierz Bragiel 《Letters in Mathematical Physics》1989,17(1):37-44
Irreducible *-representations of C(SU(3)) are constructed for ]0, 1[. It is proved that C(SU(3)) is a type-I C
*-algebra. 相似文献
7.
Rates of particle-emitting decay of the resonant state of the muonic molecular ion (dHe)
J=1 lying below the (d)1s-He threshold can decay to the d-He scattering state. The resonant state is estimated by scattering calculations with the non-adiabatic coupled-rearrangement-channel method. Strong isotope dependence of the decay rates of (d3He)
J=1 and (d4He)
J=1 is predicted, though the calculated radiative decay rates of the states are almost the same. In (d3He)
J=1, the particle decay width is three times larger than the radiative decay width, while the two types of decay widths are almost the same in (d4He)
J=1. This results in a strong hindrance of the branching ratio of the radiative decay of (d3He)
J=1 compared with the case of (d4He)
J=1. This is consistent with a recent observation of the radiative decay of the two molecular states. 相似文献
8.
We consider the thermodynamic pressurep(, ) of a classical system of particles with the two-body interaction potentialq(r)+
v
K(r), where is the number of space dimensions, is a positive parameter, and is the chemical potential. The temperature is not shown in the notation. We prove rigorously, for hard-core potentialsq(r) and for a very general class of functionsK(s), that the limit 0 of the pressurep(, ) exists and is given by where the limit and the supremum can be interchanged. Here is a certain class of nonnegative, Riemann integrable functions,D is a cube of volume |D|, anda
0() is the free energy density of a system withK=0 and density . A similar result is proved for the free energy. 相似文献
9.
Minoru Wakimoto 《Communications in Mathematical Physics》1986,104(4):605-609
The aim of this note is to show that the affine Lie algebraA
1
(1)
has a natural family , ,v of Fock representations on the spaceC[x
i,y
j;i andj ], parametrized by (,v) C
2. By corresponding the highest weight
, of , to each (,), the parameter spaceC
2 forms a double cover of the weight spaceC0C –1 with singularities at linear forms of level –2; this number is (–1)-times the dual Coxeter number. Our results contain explicit realizations of irreducible non-integrable highest wieghtA
1
(1)
-modules for generic (,v). 相似文献
10.
Henry E. Kandrup 《International Journal of Theoretical Physics》1988,27(12):1435-1455
An information-theoretic notion of entropy is proposed for a system ofN interacting particles which assesses an observer's limited knowledge of the state of the system, assuming that he or she can measure with arbitrary precision all one-particle observables and correlations involving some numberp of the particles but is completely ignorant of the form of any higher-order correlations involving more thanp particles. The idea is to define a generic measure of entropyS[
] = –Tr
log
for an arbitrary density matrix or distribution function
, and then, given the trueN-particle, to define a reduced
R
P
which reflects the observer's partial knowledge. The result, at any timet, is a chain of inequalitiesS[
R
1
]S[
R
2
]...S[
R
N
]S[], with true equalityS[
R
p
]=S[
R
p+1
] if and only if the true factorizes exactly into a product of contributions involving all possiblep-particle groupings. It follows further than (1) if, at some initial timet
0, the true factorizes in this way, thenS[
R
p
(]S[
R
p
(t
0)] for all finite timest>t
0, with equality if and only if the factorization is restored, and (2) the initial response of the system must be to increase itsp-particle entropy. 相似文献
11.
V. Doormann J. -P. Krumme C. -P. Klages M. Erman 《Applied Physics A: Materials Science & Processing》1984,34(4):223-230
Refractive-index and optical-absorption spectra of Bi-substituted yttrium iron garnet films, epitaxially grown by liquid-phase epitaxy, have been measured in the spectral regime 0.26 m1.9 m by thin-film interference for 0.52 m and by ellipsometry for0.52 m. The Y3–x–y
Bi
x
Pb
y
Fe5–z
Pt
z
O12 films contain bismuth in the range Ox 1.42, lead in the range 0.01 y0.08 and platinum in the range 0.005<=z0.03. There is satisfactory coincidence between the results from ellipsometry and thin-film interference in the overlapping wavelength region. The materials investigated are the same as reported earlier from this laboratory in ter mof their magnetic and magnetooptic properties. 相似文献
12.
W. Schott V. N. Baturin W. H. Breunlich T. Case H. Daniel F. J. Hartmann M. Jeitler P. Kammel K. Lou E. M. Maev J. Marton M. Mühlbauer C. Petitjean G. E. Petrov Yu. V. Petrov G. G. Semenchuk Yu. V. Smirenin A. A. Vorobyov P. Wojciechowski J. Zmeskal 《Hyperfine Interactions》1993,82(1-4):471-481
The triton energy of the muon capture reaction 3He t+v, where 3 He is the ground state of muonic3He, has been measured in order to investigate a possible heavy v admixture into the flavour with high sensitivity. 3 He has been formed via the pd fusion reaction by stopping – in an ionization chamber (IC) filled with an H/D gas mixture of 3% D concentration at a pressure of 161 bar. In a first short experiment 650 triton events were observed yielding an upper limit for the -heavy v mixing strength of 2.3×10–3 atE
0v=60 MeV. 相似文献
13.
C. Petitjean D. V. Balin V. N. Baturin P. Baumann W. H. Breunlich T. Case K. M. Crowe H. Daniel Yu. S. Grigoriev F. J. Hartmann A. I. Ilyin M. Jeitler P. Kammel B. Lauss K. Lou E. M. Maev J. Marton M. Mühlbauer G. E. Petrov W. Prymas W. Schott G. G. Semenchuk Yu. V. Smirenin A. A. Vorobyov N. I. Voropaev P. Wojciechowski J. Zmeskal 《Hyperfine Interactions》1993,82(1-4):273-293
The sticking process dt + n, which constitutes the most severe limit to the number of fusions which a muon can catalyze, is reviewed. Many attempts were made to determine by calculations and measurements the probability for initial sticking
s
0
(immediately after dt fusion) and for final sticking
s (after the came to rest). Previous results based on neutron disappearance rates and on the observation of -X-rays were controversial and also in some disagreement with theory. New data are reported from PSI on direct observation of final sticking, using a setup with the St. Petersburg ionization chamber. These data mark a significant improvement in reliability and may clarify questions concerning previous discrepancies. The new results is
s(0.56±0.04)%, lower than the theory prediction
s=(0.65±0.03)%, at medium density. 相似文献
14.
C. Meunier 《Journal of statistical physics》1984,36(3-4):321-365
We study a simple dynamical system which displays a so-called type-I intermittency bifurcation. We determine the Bowen-Ruelle measure and prove that the expectation (g) of any continuous functiong and the Kolmogoroff-Sinai entropyh() are continuous functions of the bifurcation parameter. Therefore the transition is continuous from a measure-theoretical point of view. Those results could be generalized to any similar dynamical system. 相似文献
15.
G. Lessner 《International Journal of Theoretical Physics》1977,16(2):99-110
An approximation method is developed to calculate the gravitational field of a matter sourceT
moving on a curved background metric that is an exact solution of the field equations and deviates only weakly from flat space-time. The fieldh
of the sourceT
is supposed to be much smaller than the curved part of the background, so that in the series expansion ofh
each order can be expanded in powers of the background. 相似文献
16.
For the first time Hlavatý represented the tensor*gv, defined by (15a), in terms of the unified field tensorg
in the space-timeX
4. Recently, the representations of*
g
v in terms ofg
in two- and three-dimensional generalized Riemannian space were obtained by Chung. The purpose of the present paper is to obtain the generalized representations of*
g
v in terms ofg
in a generalizedn-dimensional Riemannian spaceX
n. 相似文献
17.
Kenneth Dalton 《General Relativity and Gravitation》1989,21(5):533-544
In general relativity, conservation of energy and momentum is expressed by an equation of the form
/x= 0, where
–gT represents the total energy, momentum, and stress. This equation arises from the divergence formula
dV
v
= (/x
v
)d
4
d. Here we show that this formula fails to account properly for the system of basis vectors e(x). We obtain the (invariant) divergence formula
e
dV
v
= e
(/x
v
+
)d
4
d. Conservation of energy and momentum is therefore expressed by the covariant equation (/x
v
) +
= 0. We go on to calculate the variation of the action under uniform displacements in space-time. This calculation yields the covariant equation of conservation, as well as the fully symmetric energy tensor
. Finally, we discuss the transfer of energy and momentum, within the context of Einstein's theory of gravitation. 相似文献
18.
In a systematic study of the transfer process to sulphur dioxide, in seven different H2 + SO2 gas mixtures, the time spectra of the muonic sulphur X-rays yield muon transfer rates to the SO2 molecule, deduced from the lifetimes of the p atoms, which agree all well with each other. The muonic oxygen time spectra show an additional structure as if p atoms of another kind were present. Reduced transfer ratesO are reproducible if one uses the model of ephemeral p atoms. The intensity ratios between the different kinds of p atoms are also discussed in the framework of this model and the one of black and white p atoms. 相似文献
19.
K. -P. Arnold K. -P. Döring M. Gladisch N. Haas D. Herlach W. Jacobs M. Krauth S. Liebke H. Metz H. Orth H. -E. Schaefer A. Seeger 《Hyperfine Interactions》1984,17(1-4):219-224
We have measured the transverse spin relaxation of positive muons
+ in Al single crystals after irradiation at 150 K with 3 MeV electrons. The relaxation functions agree with those expected for diffusion-limited trapping of the
+ in monovacancies. Between 215 K and 60 K the
+ diffusivity is well described by the Flynn-Stoneham law (multi-phonon incoherent tunnelling between ground states) with an activation enthalpyH
a = (30±2) meV. At lower temperatures, few-phonon (in particular one-phonon) processes become important. The decrease of the vacancy concentration by a factor of 100 during annealing between 227 K and 267 K has been studied. 相似文献
20.
F. G. Van Den Berg W. Van Rijswijk W. R. Joosten W. J. Huiskamp 《Hyperfine Interactions》1985,22(1-4):579-584
Low temperature nuclear orientation experiments down to 2 mK on147GdFe,149GdFe,149GdGd and153GdGd have yielded the magnetic hyperfine interaction strength. Bhf as 31.0(1.6) NT, 28.3(2.0) NT, 33.8(4.7) NT and 13.3(2.1) NT respectively. From these values the respective ground state magnetic moments ¦¦ of147Gd,149Gd and159Gd were deduced as 1.12(20) N, 1.01(16) N and 0.40(8) N. 相似文献