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981.
It has been conjectured that a lattice in a noncompact group of real rank one, other than SU(1,n), cannot be isomorphic to the fundamental group of a compact Kähler manifold; moreover, it is known to be true for SO(1,n). In this note it is shown that this conjecture also holds for the case of uniform lattices in F4(?20), the group of isometries of the Cayley hyperbolic plane. The result is a consequence of a classification theorem for harmonic maps between Kähler and Cayley hyperbolic manifolds. 相似文献
982.
Differential calculus on quantized simple lie groups 总被引:1,自引:0,他引:1
Branislav Jurčo 《Letters in Mathematical Physics》1991,22(3):177-186
Differential calculi, generalizations of Woronowicz's four-dimensional calculus on SU
q
(2), are introduced for quantized classical simple Lie groups in a constructive way. For this purpose, the approach of Faddeev and his collaborators to quantum groups was used. An equivalence of Woronowicz's enveloping algebra generated by the dual space to the left-invariant differential forms and the corresponding quantized universal enveloping algebra, is obtained for our differential calculi. Real forms for q are also discussed. 相似文献
983.
M. L. Nazarov 《Letters in Mathematical Physics》1991,21(2):123-131
We study a superanalogue of the Yangian of the Lie algebra gl
m
. We apply our constructions to invariant theory. 相似文献
984.
Branislav Jurčo 《Letters in Mathematical Physics》1991,21(1):51-58
The coherent states for the simplest quantum groups (q-Heisenberg-Weyl, SU
q
(2) and the discrete series of representations of SU
q
(1, 1)) are introduced and their properties investigated. The corresponding analytic representations, path integrals, and q-deformation of Berezin's quantization on , a sphere, and the Lobatchevsky plane are discussed. 相似文献
985.
George D. Raikov 《Letters in Mathematical Physics》1991,21(1):41-49
We consider the Schrödinger operator with electric potential V, which decays at infinity, and magnetic potential A. We study the asymptotic behaviour for large values of the electric field coupling constant of the eigenvalues situated under the essential-spectrum lower bound. We concentrate on the cases of rapidly decaying V (e.g. V L
m/2(
m
) for m 3) and arbitrary A, or slowly decaying V (i.e. V(x |x|–
, (0,2), as |x| ) and magnetic potentials A corresponding to constant magnetic fields B = curl A.Partially supported by the Ministry of Culture, Science and Education under Grant No. 52. 相似文献
986.
Conditions were found, under which an anomalous relationship should be observed in the energies of sequential ionization of molecules ("anomalous" molecules) such that a subsequent potential (In+1) is less than the preceding potential (In). These conditions are a function of the electronic vibrational instability of molecules or their ions upon change in the number of electrons in the system. An interrelationship was found with the previously proposed concept of effective electron—electron attraction in molecular systems.Institute of Physiologically Active Compounds, Russian Academy of Sciences, 142432 Chernogolovka. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 3, pp. 738–741, March, 1992. 相似文献
987.
A second order nonlinear differential equation
相似文献
988.
Jiři Votinský Jaroslava Kalousová Ludvík Beneš 《Journal of inclusion phenomena and macrocyclic chemistry》1992,14(1):19-24
The paper deals with the relations between host lattices and guest molecules. Several types of interaction of the guest molecules and the host material are explained and some conclusions are made about the arrangement of various guest molecules in the van der Waals' gap. 相似文献
989.
I. G. Bucur 《Aequationes Mathematicae》1992,43(1):103-105
Résumé Le but de ce travail est de caractériser les éspaces topologiques qui possèdent la propriété suivant: pour toute famille(f
t
)
t I
de fonctions numériques définies dansX il existe une partie dénombrableI
0 de l'ensemble d'indicesI telle que les fonctions inf
tI
f
i
et inf
tI0
f
i
ont la meme régularisation inférieurement semi-continue.On démontre que l'espace topologiqueX possède cette propriété si et seulement si pour tout sous-ensembleA deX il existe une sous-ensemble dénombrableA
0,A
0 A tel queA
0.On généralise un résultat topologique de G. Choquet.
相似文献 990.
Janusz Matkowski 《Aequationes Mathematicae》1992,43(2-3):219-224
Summary In the present note we prove that every functionf: (0, ) [0, ) satisfying the inequalityaf(s) + bf(t) f(as + bt), s, t > 0, for somea andb such that 0 <a < 1 <a + b must be of the formf(t) = f(1)t, (t > 0). This improves our recent result in [2], where the inequality is assumed to hold for alls, t 0, and gives a positive answer to the question raised there.An analogue for functions of several real variables of the above result characterizes concave functions. Conjugate functions and some relations to Hölder's and Minkowski's inequalities are mentioned. 相似文献
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