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331.
332.
Philippe Delanoë 《Journal of Functional Analysis》1981,40(3):358-386
Let (Vn, g) be a C∞ compact Riemannian manifold. For a suitable function on Vn, let us consider the change of metric: g′ = g + Hess(), and the function, as a ratio of two determinants, M() = ¦g′¦ ¦g¦−1. Using the method of continuity, we first solve in C∞ the problem: Log M() = λ + ƒ, λ > 0, ƒ ε C∞. Then, under weak hypothesis on F, we solve the general equation: Log M() = F(P, ), F in C∞(Vn × ¦α, β¦), using a method of iteration. Our study gives rise to an interesting a priori estimate on ¦¦, which does not occur in the complex case. This estimate should enable us to solve the equation above when λ 0, providing we can overcome difficulties related to the invertibility of the linearised operator. This open question will be treated in our next article. 相似文献
333.
We extend the concepts, introduced by C.R. Rao for Euclidean norms, of minimum g-inverses and least square g-inverses, using arbitrary norms. We give a characterization of such generalized inverses and an application to the case in which the norm is l∞. As a result of this application we obtain that when has rank n, there exists a generalized inverse of A, which serves the same purpose as the Moore-Penrose inverse, when the norm is l∞. 相似文献
334.
J.M. Calleja A. Ruiz F. Flores V.R. Velasco E. Lilley 《Journal of Physics and Chemistry of Solids》1980,41(12):1367-1371
The symmetries and frequencies of the Raman active modes of the Suzuki phase in the systems 6NaCl:CdCl2; and 6NaCl:MnCl2, have been calculated. Three of the four peaks allowed by symmetry (A1g and 2Fg) agree to within 25% in position with the experimental values presented here and with other experimental results. The fourth peak (Eg) seems to be associated with a very soft mode, which explains why this peak has not been observed. The features of the Raman spectrum depend mainly upon the chlorine ions. 相似文献
335.
We present a method of computing the Coulomb forces on particles in an infinite configuration of charges in one dimension. The resolution of the apparent nonuniqueness in this problem leads to a structural proof of the translation symmetry breaking in jellium, at all temperatures, and to a related phenomenon of phase nonuniqueness in the two component system. The appropriate generalizations of the DLR and KMS conditions for these states are discussed.Supported in part by U.S. National Science Foundation, grant No. PHY-78 25390 A01 相似文献
336.
Some 5-alkylidene 2-alkyl 1,3-dioxans have been studied by NMR. Analysis of the spectra leads to the conclusion that these derivatives are predominantly in the chair form, the alkyl substituent on carbon 2 being in the equatorial position. In the case of 5-alkylidene 1,3 dioxans unsubstituted at carbon 2, there is a rapid ring inversion with a very low energy barrier. 相似文献
337.
Theoretical constraints and limits on the masses of Higgs scalars in the standard electroweak model, in electroweak models with additional Higgs doublets and in various supersymmetric models are presented. In the standard model, the lower limit on the Higgs mass, based on vacuum stability arguments, is reviewed in detail, as are “upper limits” based on perturbative constraints. In most grand unified and all supersymmetric models, however, at least two doublets are needed. The masses of the various Higgs scalars in the two-doublet model are discussed and constraints on their masses are found, including the generalization of the above limits. The results are then generalized to models with more than two doublets. Finally, recent attempts at constructing models with low-energy supersymmetry are reviewed and it is shown that in many models, fairly stringent tree-level mass relations among the Higgs scalars can be found. These relations are interesting in that they do not refer to the supersymmetric partners of ordinary particles, and they are most restrictive in models in which the supersymmetry is explicitly broken, i.e., via arbitrary mass terms. 相似文献
338.
Eric Arie Nelly Lacome Philippe Arcas 《Journal of Quantitative Spectroscopy & Radiative Transfer》1978,20(4):425-426
Using intensity measurements on the CO2 40°1II-00°0 band obtained by Valero and Boese, we have expanded the F(m)-factor for the parallel band by using the Herman-Wallis formula. We have calculated the transition moment and determined the coefficients in the expansion of F(m). 相似文献
339.
The quasi-particle density of states of the one-dimensional Anderson-Hubbard Hamiltonian has been calculated. The effect of correlation on the local density of states of a disordered chain is shown to depend critically on the energy region. 相似文献
340.
The absorption spectrum of CO2 in the 4.82-μm region has been observed with a high-resolution spectrometer. The (1110, 0310)I-0000 transition and the “hot” transitions (1220, 0420)I-0110 and (2000, 0400)I-0110 have been calibrated. The effective rotational constants of the upper levels have been deduced with good accuracy. 相似文献