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51.
For a general K3 surface S of genus g, with 2 ≤ g ≤ 10, we prove that the intermediate Jacobians of the family of prime Fano threefolds of genus g containing S as a hyperplane section, form generically an algebraic completely integrable Hamiltonian system.
The first author is partially supported by grant MI1503/2005 of the Bulgarian Foundation for Scientific Research. 相似文献
52.
In this paper, we establish a theorem on the distribution of primes in quadratic progressions on average. 相似文献
53.
H. Maekawa K. Tsubakihara A. Ohnishi 《The European Physical Journal A - Hadrons and Nuclei》2007,33(3):269-272
We study the hyperon-nucleus potential with distorted-wave impulse wave approximation (DWIA) using the Green's function method.
In order to include the nucleon and hyperon potential effects in Fermi averaging, we introduce the local optimal momentum
approximation of target nucleons. We can describe the quasi-free Λ , Σ and Ξ production spectra in a better way than in the
standard Fermi-averaged t -matrix treatments. 相似文献
54.
By exploiting the construction of charged field algebras as canonical extensions of CCR current algebras in 1+1 dimensions and nonregular representations of extended algebras, we provide an algebraic construction of local Fermi fields as ultrastrong limits of bosonic variables in all representations which are locally Fock with respect to the ground-state representation of the massless scalar field. 相似文献
55.
56.
Marcel Erné 《Order》1991,8(2):159-173
We introduce a special type of order-preserving maps between quasiordered sets, the so-called cut-stable maps. These form the largest morphism class such that the corresponding category of quasiordered sets contains the category of complete lattices and complete homomorphisms as a full reflective subcategory, the reflector being given by the Dedekind-MacNeille completion (alias normal completion or completion by cuts). Suitable restriction of the object class leads to the category of separated quasiordered sets and its full reflective subcategory of completely distributive lattices. Similar reflections are obtained for continuous lattices, algebraic lattices, etc. 相似文献
57.
58.
LetC(X,E) andC(Y,F) denote the spaces of continuous functions on the Tihonov spacesX andY, taking values in the Banach spacesE andF, respectively. A linear mapH:C(X,E)→C(Y,F) isseparating iff(x)g(x)=0 for allx inX impliesHf(y)Hg(y)=0 for ally inY. Some automatic continuity properties and Banach-Stone type theorems (i.e., asserting that isometries must be of a certain
form) for separating mapsH between spaces of real- and complex-valued functions have already been developed. The extension of such results to spaces
of vector-valued functions is the general subject of this paper. We prove in Theorem 4.1, for example, for compactX andY, that a linear isometryH betweenC(X,E) andC(Y,F) is a “Banach-Stone” map if and only ifH is “biseparating (i.e,H andH
−1 are separating). The Banach-Stone theorems of Jerison and Lau for vector-valued functions are then deduced in Corollaries
4.3 and 4.4 for the cases whenE andF or their topological duals, respectively, are strictly convex.
Research supported by the Fundació Caixa Castelló, MI/25.043/92 相似文献
59.
A. Kontogeorgis 《Journal of Pure and Applied Algebra》2007,210(2):551-558
We give a relation between the dimension of the tangent space of the deformation functor of curves with automorphisms and the Galois module structure of the space of 2-holomorphic differentials. We prove a homological version of the local-global principle similar to the one of J. Bertin and A. Mézard. Let G be a cyclic subgroup of the group of automorphisms of a curve X, so that the order of G is equal to the characteristic. By using the results of S. Nakajima on the Galois module structure of the space of 2-holomorphic differentials, we compute the dimension of the tangent space of the deformation functor. 相似文献
60.
Perch Melik-Adamyan 《Complex Analysis and Operator Theory》2007,1(3):423-438
An analog of the Kreĭn–Saakyan formula is derived for any pair of relatively prime self-adjoint extensions of a minimal symmetric
canonical differential operator. This allows us to deduce a trace formula in the matrix case.
I am grateful to Sh. Saakyan for his interest in this work and lively discussion.
Received: December 8, 2006. Accepted: December 30, 2006. 相似文献