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71.
The subject of spectral distribution methods where one derives and applies the locally smoothed forms of observables in nuclei
is briefly reviewed. It is well understood that the local forms (with respect to energy) of the level density function, expectation
values and strength densities are Gaussian, linear (or ratio of Gaussians) and a bivariate Gaussian respectively. To accomodate
symmetries in the above forms, one has to deal with multivariate distributions in general; for example the angular-momentum
(J) decomposition leads to a bivariate Gaussian form for the level density. These results extend to indefinitely large spaces
by method of partitioning and they generate convolution forms. The origin of these remarkable spectral properties is discussed
and shell model examples are given to substantiate their applicability to nuclear systems. Spectral distribution theory is
a practical, usable theory because the smoothed forms are defined in terms of traces of low particle-rank operators, and the
trace information propagates. Finally we discuss the application of the spectral methods for a wide range of nuclear problems;
these include binding energies, orbit occupancies, electromagnetic andβ-decay sum rule quantities, analysis of operators, symmetry breaking, numerical level densities, and determination of bounds
on time-reversal non-invariant part of nucleon-nucleon interaction. 相似文献
72.
Mathematical Notes - 相似文献
73.
Yuichiro Fujiwara 《组合设计杂志》2006,14(3):237-250
In this paper, we present three constructions for anti‐mitre Steiner triple systems and a construction for 5‐sparse ones. The first construction for anti‐mitre STSs settles two of the four unsettled admissible residue classes modulo 18 and the second construction covers such a class modulo 36. The third construction generates many infinite classes of anti‐mitre STSs in the remaining possible orders. As a consequence of these three constructions we can construct anti‐mitre systems for at least 13/14 of the admissible orders. For 5‐sparse STS(υ), we give a construction for υ ≡ 1, 19 (mod 54) and υ ≠ 109. © 2005 Wiley Periodicals, Inc. J Combin Designs 14: 237–250, 2006 相似文献
74.
In this paper we describe the general forms of all (nonlinear) continuous functionals on the sets of positive definite, positive semi-definite and Hermitian matrices which are multiplicative on the commuting elements. As a consequence, we obtain some new characterizations of the determinant on those classes of matrices.
75.
A linear three‐dimensional hydrodynamical numerical model, with the application of the Galerkin Method for the vertical dependence, is here presented. The spherical coordinate system is used, in order to allow large‐scale simulations. The equations and mathematical development of the model are shown in detail, together with the boundary and initial conditions, and the sequence of equations' solution. The model is applied to the South Atlantic Ocean, for estimating typical seasonal circulations, and the results are summarized in maps of currents at surface and 1000 m depth, and in transport values of the Brazil Current between 30°S and 40°S. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
76.
This article explores the use of geometric algebra in linear and multilinear algebra, and in affine, projective and conformal geometries. Our principal objective is to show how the rich algebraic tools of geometric algebra are fully compatible with and augment the more traditional tools of matrix algebra. The novel concept of an h-twistor makes possible a simple new proof of the striking relationship between conformal transformations in a pseudo-Euclidean space to isometries in a pseudo-Euclidean space of two higher dimensions. The utility of the h-twistor concept, which is a generalization of the idea of a Penrose twistor to a pseudo-Euclidean space of arbitrary signature, is amply demonstrated in a new treatment of the Schwarzian derivative. 相似文献
77.
The main objects of study in this article are two classes of Rankin–Selberg L-functions, namely L(s,f×g) and L(s, sym2(g)× sym2(g)), where f,g are newforms, holomorphic or of Maass type, on the upper half plane, and sym2(g) denotes the symmetric square lift of g to GL(3). We prove that in general, i.e., when these L-functions are not divisible by L-functions of quadratic characters (such divisibility happening rarely), they do not admit any LandauSiegel zeros. Such zeros, which are real and close to s=1, are highly mysterious and are not expected to occur. There are corollaries of our result, one of them being a strong lower bound for special value at s=1, which is of interest both geometrically and analytically. One also gets this way a good bound onthe norm of sym2(g). 相似文献
78.
Atsushi Kasue 《Potential Analysis》2006,24(2):137-194
We study spectral convergence of compact Riemannian manifolds or more generally certain Dirichlet spaces, obtaining some compactness
results on harmonic functions and harmonic maps.
Mathematics Subject Classifications (2000) 53C21, 58D17, 58J50.
Atsushi Kasue: Partly supported by the Grant-in-Aid for Scientific Research (B) No. 15340053 of the Japan Society for the
Promotion of Science. 相似文献
79.
P. Kh. Atanasova T. L. Bojadjiev S. N. Dimova 《Computational Mathematics and Mathematical Physics》2006,46(4):666-679
Partial critical dependences of the form current-magnetic field in a two-layered symmetric Josephson junction are modeled. A numerical experiment shows that, for the zero interaction coefficient between the layers of the junction, jumps of the critical currents corresponding to different distributions of the magnetic fluxes in the layers may appear on the critical curves. This fact allows a mathematical interpretation of the results of some recent experimental results for two-layered junctions as a consequence of discontinuities of partial critical curves. 相似文献
80.