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91.
In this work we present a mapping between the classical solutions of the sine-Gordon, Liouville, 4 and other kinks in 1+1 dimensions. This is done by using an invariant quantity which relates the models. It is easily shown that this procedure is equivalent to that used to get the so called deformed solitons, as proposed recently by Bazeia et al. [Phys. Rev. D. 66 (2002) 101701(R)]. The classical equivalence is explored in order to relate the solutions of the corresponding models and, as a consequence, try to get new information about them. We discuss also the difficulties and consequences which appear when one tries to extend the deformation in order to take into account the quantum version of the models. 相似文献
92.
We obtain an upper bound for the quantity
. Here I is an interval,
is the set of rational numbers q=m/n
I such that nx, and f(q) is an arbitrary real-valued additive function of rational argument. The interval I and function f may depend on x3. 相似文献
93.
T. J. Sumner 《General Relativity and Gravitation》2004,36(10):2331-2339
Over the centuries there have been many experimental tests of the universality of free-fall. To date, these measurements have established the equivalence between inertial and gravitational mass to high precision, justifying its use as a foundation stone of general relativity by Einstein. There is a surprising richness in the variety of techniques and choice of test bodies which have been used so far, and a brief review is presented. However, future space experiments promise much better precision in this measurement and STEP is presented in some detail as one of a number of such missions. Using pairs of concentric free-falling proof-masses, STEP will be able to test the Equivalence Principle (EP) to a sensitivity at least five orders of magnitude better than currently achievable on ground. The EP is a founding principle of general relativity and STEP is the most sensitive experiment of this type planned so far, aiming at 1 part in 1018. 相似文献
94.
For a strictly decreasing sequence an
n=0 of nonnegative real numbers converging to zero, we construct a continuous 2-periodic function f such that RT
n(f) = an, n=0,1,2,..., where RT
n(f) are best approximations of the function f in uniform norm by trigonometric rational functions of degree at most n. 相似文献
95.
Dunkl Operators for Complex Reflection Groups 总被引:3,自引:0,他引:3
Dunkl operators for complex reflection groups are defined inthis paper. These commuting operators give rise to a parameterizedfamily of deformations of the polynomial De Rham complex. Thisleads to the study of the polynomial ring as a module over therational Cherednik algebra, and a natural contravariantform on this module. In the case of the imprimitive complexreflection groups G(m, p, N), the set of singular parametersin the parameterized family of these structures is describedexplicitly, using the theory of non-symmetric Jack polynomials.2000 Mathematical Subject Classification: 20F55 (primary), 52C35,05E05, 33C08 (secondary). 相似文献
96.
Sigal Leviatan 《International Journal of Game Theory》2003,31(3):383-410
The consistent value is an extension of the Shapley value to the class of games with non-transferable utility.? In this paper,
the consistent value will be characterized for market games with a continuum of players of two types. We will show that for
such games the consistent value need not belong to the core, and provide conditions under which there is equivalence between
the two concepts.
Received: October 1998
RID="*"
ID="*" This thesis was completed under the supervision of Professor Sergiu Hart, The Center for Rationality and Interactive
Decision Theory, Department of Mathematics, Department of Economics, The Hebrew University of Jerusalem. I would like to thank
Professor Hart for introducing me to this area of research, for his help and guidance, and, especially, for all his patience.? I
would also like to thank Michael Borns for improving the style, and an anonymous referee for helpful comments. 相似文献
97.
We investigate the groups of equivalence transformations for first-order balance equations involving an arbitrary number of dependent and independent variables. We obtain the determining equations and find their explicit solutions. The approach to this problem is based on a geometric method that depends on Cartan's exterior differential forms. The general solutions of the determining equations for equivalence transformations for first-order systems are applied to a class of the Maxwell equations of electrodynamics. 相似文献
98.
We consider the question of preservation of universal equivalence for the cartesian and direct wreath products of lattice-ordered groups and groups. We prove that the basic rank is infinite of the quasivariety of torsion-free nilpotent groups of nilpotence length c (c2) 相似文献
99.
Han-Fu ChenAcademy of Mathematics Systems Science Chinese Academy of Sciences Beijing China 《应用数学学报(英文版)》2003,19(4):573-580
Abstract For the multidimensional ARMA system A(z)y_k=C(z)w_k it is shown that stability(det A(z)≠0,z:│z│≤1)of A(z) is equivalent to the trajectory boundedness in the mean square sense(MSS)which,as a rule,is a consequence of a successful stochastic adaptive control leading the closed-loop of an ARMAXsystem to a steady state ARMA system.In comparison with existing results the stability condition imposed onC(z)is no longer needed.The only structural requirement on the system is that det A(z) and det C(z) have nounstable common factor. 相似文献
100.
V. P. Lexin 《Acta Appl Math》2003,75(1-3):105-115
A special class of integrable Fuchsian systems on C
n
related to KZ equations is considered. We survey the construction of such systems and the list of the structural properties their monodromy representations. The relation of the Fuchsian systems obtained by the Veselov construction assosiated with a deformation of the A
n–1-type root system and the Gauss–Manin connection of the natural projection C
n
C
n–1 is described. In this case, we prove that the monodromy representation is equivalent to the Burau representation of the Artin braid group. For a deformations of the other root system, we introduce generalized Burau representations. We conjecture that the integrable Fuchsian systems related to essential new finite sets of the vectors described by Veselov and Chalykh are the result of the Klares–Schlesinger isomonodromic deformations (or transformation) of the integrable Fuchsian system related to the Coxeter root systems. 相似文献