共查询到20条相似文献,搜索用时 15 毫秒
1.
Jean B. Lasserre 《Journal of Algebraic Combinatorics》2002,16(3):231-237
We provide a characterization of the real-valued univariate polynomials that have only real zeros, all in a prescribed interval [a,b]. The conditions are stated in terms of positive semidefiniteness of related Hankel matrices. 相似文献
2.
In this paper, we classify all optimal linear[n, n/2] codes up to length 12. We show that thereis a unique optimal [10, 5, 5] code up to equivalence. 相似文献
3.
Michael Reid 《Compositio Mathematica》2003,137(1):75-90
A refinement of the rank 1 Abelian Stark conjecture has been formulated by B.Gross. This conjecture predicts some
-adic analytic nature of a modification of the Stark unit. The conjecture makes perfect sense even when
is an Archimedean place. Here we consider the conjecture when
is a real place, and interpret it in terms of 2-adic properties of special values of L-functions. We prove the conjecture for CM extensions; here the original Stark conjecture is uninteresting, but the refined conjecture is nontrivial. In more generality, we show that, under mild hypotheses, if the subgroup of the Galois group generated by complex conjugations has less than full rank, then the refined conjecture implies that the Stark unit should be a square. This phenomenon has been discovered by Dummit and Hayes in a particular type of situation. We show that it should hold in much greater generality. 相似文献
4.
V. F. Murzina 《Algebra and Logic》2003,42(3):181-191
A modal logic associated with the
-spaces introduced by Ershov is examined. We construct a modal calculus that is complete w.r.t. the class of all strictly linearly ordered
-frames, and the class of all strictly linearly ordered
-frames. 相似文献
5.
The main goal of the paper is to give explicit formulas for the fundamental classes of Schubert subschemes in Lagrangian and orthogonal Grassmannians of maximal isotropic subbundles as well as some globalizations of them. The used geometric tools overlap appropriate desingularizations of such Schubert subschemes and Gysin maps for such Grassmannian bundles. The main algebraic tools are provided by the families of
and
-polynomials introduced and investigated in the present paper. The key technical result of the paper is the computation of the class of the (relative) diagonal in isotropic Grassmannian bundles based on the orthogonality property of
and
polynomials. Some relationships with quaternionic Schubert varieties and Schubert polynomials for classical groups are also discussed. 相似文献
6.
B. Konopelchenko L. Martínez Alonso E. Medina 《Theoretical and Mathematical Physics》2002,133(2):1529-1538
A
formalism for studying dispersionless integrable hierarchies is applied to the dispersionless KP (dKP) hierarchy. We relate this formalism to the theory of quasiconformal mappings on the plane and present some classes of explicit solutions of the dKP hierarchy. 相似文献
7.
GÉRARD Laumon 《Compositio Mathematica》1997,105(3):267-359
In this paper we compute the cohomology with compact supports of a Siegelthreefold as a virtual module over the product of the Galois group of
over
and the Hecke algebra. We use a method which has been developed by Ihara, Langlands and Kottwitz: comparison of the Grothendieck--Lefschetz formula and the Arthur--Selberg trace formula. 相似文献
8.
With the help of some new results about weight enumerators of self-dual codes over
we investigate a class of double circulant codes over
, one of which leads to an extremal even unimodular 40–dimensional lattice. It is conjectured that there should be Nine more constructions of the Leech lattice 相似文献
9.
A. V. Kravchenko 《Algebra and Logic》2002,41(3):173-181
It is proved that a quasivariety K of undirected graphs without loops is
-universal if and only if K contains some non-bipartite graph. 相似文献
10.
We show that, under conditions about the microcharacteristic variety of a coherent
-module, the Cauchy problem is well-posed in the spaces of formal power series with Gevrey growth. We deduce that the filtration of the Irregularity Sheaf of a holonomic
-module, which we defined in a previous work, is preserved under inverse image if some rather general geometric conditions are fullfilled. 相似文献
11.
We calculate the skew-symmetric cohomology of the complement of a discriminantal hyperplane arrangement with coefficients in local systems arising in the context of the representation theory of the Lie algebra
. For a discriminantal arrangement in k, the skew-symmetric cohomology is nontrivial in dimension k–1 precisely when the 'master function' which defines the local system on the complement has nonisolated criticalpoints. In symmetric coordinates, the critical set is a union of lines. Generically, the dimension of this nontrivial skew-symmetric cohomology group is equal to the number of critical lines. 相似文献
12.
The appearance of the theory of zero-knowledge, presented by Goldwasser, Micali and Rackoff in 1985, opened a way to secure identification schemes. The first application was the famous Fiat-Shamir scheme based on the problem of modular square roots extraction. In the following years, many other schemes have been proposed, some Fiat-Shamir extensions but also new discrete logarithm based schemes. Therefore, all of them were based on problems from number theory. Their main common drawback is high computational load because of arithmetical operations modulo large integers. Implementation on low-cost smart cards was made difficult and inefficient.With the Permuted Kernels Problem (PKP), Shamir proposed the first efficient scheme allowing for an implementation on such low-cost smart cards, but very few others have afterwards been suggested.In this paper, we present an efficient identification scheme based on a combinatorial
-complete problem: the Permuted Perceptrons Problem (PPP). This problem seems hard enough to be unsolvable even with very small parameters, and some recent cryptanalysis studies confirm that position. Furthermore, it admits efficient zero-knowledge proofs of knowledge and so it is well-suited for cryptographic purposes. An actual implementation completes the optimistic opinion about efficiency and practicability on low-cost smart cards, and namely with less than 2KB of EEPROM and just 100 Bytes of RAM and 6.4 KB of communication. 相似文献
13.
Generalizing techniques developed by Cuesta and Matrán for Bochner integrable random vectors of a separable Banach space, we prove a strong law of large numbers for Pettis integrable random elements of a separable locally convex space E. This result may be seen as a compactness result in a suitable topology on the set of Pettis integrable probabilities on E. 相似文献
14.
Marek Golasiński 《Compositio Mathematica》2000,124(1):1-9
Let X be a G-connected nilpotent simplicial set, where G is a finite Hamiltonian group. We construct a cofibrant equivariant minimal model of X with the strong homotopy type of the injective minimal model of X defined by Triantafillou. 相似文献
15.
In this paper, we use Zorn’s Lemma, multiplicatively closed subsets and saturated closed subsets for the following two topics
(i) The existence of prime submodules in some cases
(ii) The proof that submodules with a certain property satisfy the radical formula.
We also give a partial characterization of a submodule of a projective module which satisfies the prime property. 相似文献
16.
We consider conditions under which the distributions of sequences of integer-valued nonnegative strongly additive functions can be approximated by the distributions of sums of independent random variables.__________Translated from Lietuvos Matematikos Rinkinys, Vol. 45, No. 2, pp. 270–281, April–June, 2005. 相似文献
17.
18.
Let X be a complex analytic manifold,
a C
2 submanifold,
an openset with C
2 boundary
.Denote by
(resp.
) the microlocalization along M (resp.
) of the sheaf
of holomorphic functions.In the literature (cf. [A-G], [K-S 1,2])one encounters two classical results concerning the vanishing of the cohomology groups
.The most general gives the vanishing outside a range of indices j whose length is equal to
(with
being the number of respectively positive, negative and null eigenvalues for themicrolocal Levi form
).The sharpest result gives the concentration in a single degree, provided that the difference
is locally constant for
near p (with
for z the base point of p).The first result was restated for the complex
in [D'A-Z 2], in the case codim
We extend it here to any codimension and moreover we also restate for
the second vanishing theorem.We also point out that the principle of our proof, related to a criterion for constancy of sheaves due to [K-S 1], is a quite new one. 相似文献
19.
Let
be an Abelian Archimedean lattice ordered algebra. The order bidual
furnished with the Arens product is again a lattice ordered algebra. We show that the order continuous order bidual
is Abelian. This solves an open problem and improves a result of Scheffold, who proved it for the case of normed lattice ordered algebras. The proof is based on the up-down-up approximation of positive elements in the order continuous order bidual
by elements in the canonical image
of
in
Components of positive elements in
are characterized and the result is applied to the Arens product of
-and almost
-algebras. 相似文献
20.
O. Duman 《Czechoslovak Mathematical Journal》2007,57(1):367-375
Using the concept of
-convergence we provide a Korovkin type approximation theorem by means of positive linear operators defined on an appropriate
weighted space given with any interval of the real line. We also study rates of convergence by means of the modulus of continuity
and the elements of the Lipschitz class. 相似文献