共查询到20条相似文献,搜索用时 31 毫秒
1.
Mirjana Stojanović 《Acta Appl Math》2006,92(1):1-14
We consider several types of nonlinear parabolic equations with singular like potential and initial data. To prove the existence-uniqueness theorems we employ regularized derivatives. As a framework we use Colombeau space
and Colombeau vector space
相似文献
2.
Let G be a connected graph. For at distance 2, we define , and , if then . G is quasi-claw-free if it satisfies , and G is P
3-dominated() if it satisfies , for every pair (x, y) of vertices at distance 2. Certainly contains as a subclass. In this paper, we prove that the circumference of a 2-connected P
3-dominated graph G on n vertices is at least min or , moreover if then G is hamiltonian or , where is a class of 2-connected nonhamiltonian graphs. 相似文献
3.
Amol Sasane 《Acta Appl Math》2008,103(2):161-168
In this article, we prove that the Krull dimension of several commonly used classes of transfer functions of infinite dimensional
linear control systems is infinite. On the other hand, we also show that the weak Krull dimension of the Hardy algebra
, the disk algebra
and the Wiener algebra
is equal to 1.
A. Sasane is supported by the Nuffield Grant NAL/32420. 相似文献
4.
J. Pohjanpelto 《BIT Numerical Mathematics》2008,48(2):337-355
A symmetry-based method for constructing solutions to systems of differential equations founded on the reduction of exterior
differential systems invariant under the action of an infinite dimensional pseudogroup is proposed. One can associate to any
system of differential equations Δ=0 with a symmetry group an exterior differential system invariant under so that solutions of Δ=0 correspond to integral manifolds . The -invariant exterior differential system gives rise to a reduced system specified on a cross section to the pseudogroup orbits, and it is shown that solutions to Δ=0 can be reconstructed from integral
manifolds by solving an equation of generalized Lie type for the jets of pseudogroup transformations. In particular, as opposed to
the classical method of symmetry reduction, every solution to the system of differential equations can, under some mild regularity
assumptions, be constructed by the present algorithm.
AMS subject classification (2000) 58A15, 58A20, 58H05, 58J70 相似文献
5.
Emanuele Delucchi 《Journal of Algebraic Combinatorics》2007,26(4):477-494
Given a finite group G and a natural number n, we study the structure of the complex of nested sets of the associated Dowling lattice
(Proc. Internat. Sympos., 1971, pp. 101–115) and of its subposet of the G-symmetric partitions
which was recently introduced by Hultman (, 2006), together with the complex of G-symmetric phylogenetic trees
. Hultman shows that the complexes
and
are homotopy equivalent and Cohen–Macaulay, and determines the rank of their top homology.
An application of the theory of building sets and nested set complexes by Feichtner and Kozlov (Selecta Math. (N.S.)
10, 37–60, 2004) shows that in fact
is subdivided by the order complex of
. We introduce the complex of Dowling trees
and prove that it is subdivided by the order complex of
. Application of a theorem of Feichtner and Sturmfels (Port. Math. (N.S.)
62, 437–468, 2005) shows that, as a simplicial complex,
is in fact isomorphic to the Bergman complex of the associated Dowling geometry.
Topologically, we prove that
is obtained from
by successive coning over certain subcomplexes. It is well known that
is shellable, and of the same dimension as
. We explicitly and independently calculate how many homology spheres are added in passing from
to
. Comparison with work of Gottlieb and Wachs (Adv. Appl. Math.
24(4), 301–336, 2000) shows that
is intimely related to the representation theory of the top homology of
.
Research partially supported by the Swiss National Science Foundation, project PP002-106403/1. 相似文献
6.
Wenbin Guo 《manuscripta mathematica》2008,127(2):139-150
Let G be a finite group and a formation of finite groups. We say that a subgroup H of G is -supplemented in G if there exists a subgroup T of G such that G = TH and is contained in the -hypercenter of G/H
G
. In this paper, we use -supplemented subgroups to study the structure of finite groups. A series of previously known results are unified and generalized.
Research of the author is supported by a NNSF grant of China (Grant #10771180). 相似文献
7.
In this paper we show that each factorization structure on a small category , satisfying certain conditions, yields a presheaf on and a morphism of presheaves . We then give connections, and set up one to one correspondences, between subclasses of the following classes: (a) closure operators on (b) subobjects of (c) morphisms from to (d) weak Lawvere–Tierney topologies (e) weak Grothendieck topologies (f) closure operators on . 相似文献
8.
The unbalance of an intersecting family is defined as , where is the maximum degree of i.e. the maximum of over all vertices x. We show that the unbalance of a k-uniform intersecting family is at most when n ≥ 6k
3 and we determine all families achieving this bound. 相似文献
9.
Yonutz V. Stanchescu 《Combinatorica》2008,28(3):343-355
We describe the structure of three dimensional sets of lattice points, having a small doubling property. Let be a finite subset of ℤ3 such that dim = 3. If and , then lies on three parallel lines. Moreover, for every three dimensional finite set that lies on three parallel lines, if , then is contained in three arithmetic progressions with the same common difference, having together no more than terms. These best possible results confirm a recent conjecture of Freiman and cannot be sharpened by reducing the quantity
υ or by increasing the upper bounds for . 相似文献
10.
Ilwoo Cho 《Acta Appl Math》2007,95(2):95-134
In this paper, we will define a graph von Neumann algebra over a fixed von Neumann algebra M, where G is a countable directed graph, by a crossed product algebra = M ×
α
, where is the graph groupoid of G and α is the graph-representation. After defining a certain conditional expectation from onto its M-diagonal subalgebra we can see that this crossed product algebra is *-isomorphic to an amalgamated free product
where = vN(M ×
α
where is the subset of consisting of all reduced words in {e, e
–1} and M ×
α
is a W
*-subalgebra of as a new graph von Neumann algebra induced by a graph G
e
. Also, we will show that, as a Banach space, a graph von Neumann algebra is isomorphic to a Banach space ⊕
where is a certain subset of the set E(G)* of all words in the edge set E(G) of G.
The author really appreciates to Prof F. Radulescu and Prof P. Jorgensen for the valuable discussion and kind advice. Also,
he appreciates all supports from St. Ambrose Univ.. In particular, he thanks to Prof T. Anderson and Prof V. Vega for the
useful conversations and suggestions. 相似文献
11.
In this paper, we study and classify Hilbert space representations of cross product -algebras of the quantized enveloping algebra with the coordinate algebras of the quantum motion group and of the complex plane, and of the quantized enveloping algebra with the coordinate algebras of the quantum group and of the quantum disc. Invariant positive functionals and the corresponding Heisenberg representations are explicitly described.Presented by S.L. Woronowicz. 相似文献
12.
T. Skrypnyk 《Acta Appl Math》2007,99(3):261-282
We construct a family of special quasigraded Lie algebras
of functions of one complex variables with values in finite-dimensional Lie algebra
, labeled by the special 2-cocycles F on
. The main property of the constructed Lie algebras
is that they admit Kostant-Adler-Symes scheme. Using them we obtain new integrable finite-dimensional Hamiltonian systems
and new hierarchies of soliton equations. 相似文献
13.
Jean-André Marti 《Acta Appl Math》2009,105(3):267-302
We introduce a general context involving a presheaf
and a subpresheaf ℬ of
. We show that all previously considered cases of local analysis of generalized functions (defined from duality or algebraic
techniques) can be interpretated as the ℬ-local analysis of sections of
.
But the microlocal analysis of the sections of sheaves or presheaves under consideration is dissociated into a “frequential
microlocal analysis” and into a “microlocal asymptotic analysis”. The frequential microlocal analysis based on the Fourier
transform leads to the study of propagation of singularities under only linear (including pseudodifferential) operators in
the theories described here, but has been extended to some non linear cases in classical theories involving Sobolev techniques.
The microlocal asymptotic analysis is a new spectral study of singularities. It can inherit from the algebraic structure of
ℬ some good properties with respect to nonlinear operations.
相似文献
14.
M. Laura Arias Gustavo Corach M. Celeste Gonzalez 《Integral Equations and Operator Theory》2008,62(1):11-28
Several results on norms of projections on a Hilbert space are extended for the operator seminorm defined by a positive semidefinite operator .
The authors were supported in part by UBACYT I030, ANPCYT PICT 03-09521, PIP 2188/00. 相似文献
15.
Hideo Mitsuhashi 《Algebras and Representation Theory》2006,9(3):309-322
In this paper, we establish Schur–Weyl reciprocity between the quantum general super Lie algebra and the Iwahori–Hecke algebra . We introduce the sign -permutation representation of on the tensor space of dimensional -graded -vector space . This action commutes with that of derived from the vector representation on . Those two subalgebras of satisfy Schur–Weyl reciprocity. As special cases, we obtain the super case (), and the quantum case (). Hence this result includes both the super case and the quantum case, and unifies those two important cases.Presented by A. Verschoren. 相似文献
16.
17.
Albert Wiltsche 《Journal of Geometry》2008,88(1-2):178-193
We discuss all automorphisms of which have a space cubic (twisted cubic) as a fixed figure. These automorphisms build up a three-parameter subgroup of all collineations of . In this paper we study the one-parameter subgroups of , their paths and tangent complexes.
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18.
The aim of this paper is to give some representation formulas of Riesz and Poisson-Jensen type for super-solutions to a class
of hypoelliptic ultraparabolic operators on a homogeneous Lie group . Our results complete the ones obtained in Cinti (Math Scand 100:1–21, 2007). We also provide a suitable theory for -Green functions and for -Green potentials of Radon measures. The proofs mostly rely on the use of appropriate techniques relevant to the Potential
Theory for .
Investigation supported by University of Bologna. Funds for selected research topics. 相似文献
19.
A. Vourdas 《Acta Appl Math》2006,93(1-3):197-214
Quantum systems in which the position and momentum take values in the ring and which are described with -dimensional Hilbert space, are considered. When is the power of a prime, the position and momentum take values in the Galois field , the position-momentum phase space is a finite geometry and the corresponding ‘Galois quantum systems’ have stronger properties. The study of these systems uses ideas from the subject of field extension in the context of quantum mechanics. The Frobenius automorphism in Galois fields leads to Frobenius subspaces and Frobenius transformations in Galois quantum systems. Links between the Frobenius formalism and Riemann surfaces, are discussed. 相似文献
20.
Let B be a nilpotent matrix and suppose that its Jordan canonical form is determined by a partition λ. Then it is known that its
nilpotent commutator is an irreducible variety and that there is a unique partition μ such that the intersection of the orbit of nilpotent matrices corresponding to μ with is dense in . We prove that map given by is an idempotent map. This answers a question of Basili and Iarrobino [9] and gives a partial answer to a question of Panyushev [18]. In the proof, we use the fact that for a generic matrix the algebra generated by A and B is a Gorenstein algebra. Thus, a generic pair of commuting nilpotent matrices generates a Gorenstein algebra. We also describe
in terms of λ if has at most two parts. 相似文献