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21.
讨论由Young函数生成的Orlicz空间L*_Φ(0,∞)的性质,并给出Orlicz空间L*_Φ(0,∞)具有Hardy-Littlewood性质的充要条件,然后借助加Jacobi权修正的K-泛函和加Jacobi权连续模及其等价性建立Gamma算子在Orlicz空间L*_Φ(0,∞)中加权同时逼近的两种强逆不等式.  相似文献   
22.
In a recent paper [O. Bärwald, R.W. Gebert, M. Günaydin and H. Nicolai, preprint KCL-MTH-97-22, IASSNS-HEP-97/20, PSU-TH-178, AEI-029, hep-th/9703084, to appear in Commun. Math. Phys.] it was conjectured that the imaginary simple roots of the Borcherds algebra II9,1 at level 1 are its only ones. We here propose an independent test of this conjecture, establishing its validity for all roots of norm − 8. However, the conjecture fails for roots of norm −10 and beyond, as we show by computing the simple multiplicities down to norm −24, which turn out to be remarkably small in comparison with the corresponding E10 multiplicities. Our derivation is based on a modified denominator formula combining the denominator formulas for E10 and II9,1, and provides an efficient method for determining the imaginary simple roots. In addition, we compute the E10 multiplicities of all roots up to height 231, including levels up to l = 6 and norms −42.  相似文献   
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24.
The Bethe strip of width m is the cartesian product $\mathbb {B}\times \lbrace 1,\ldots ,m\rbrace$, where $\mathbb {B}$ is the Bethe lattice (Cayley tree). We prove that Anderson models on the Bethe strip have “extended states” for small disorder. More precisely, we consider Anderson‐like Hamiltonians $H_\lambda =\frac{1}{2} \Delta \otimes 1 + 1 \otimes A\,+\,\lambda \mathcal {V}$ on a Bethe strip with connectivity K ≥ 2, where A is an m × m symmetric matrix, $\mathcal {V}$ is a random matrix potential, and λ is the disorder parameter. Given any closed interval $I\subset \big (\!-\!\sqrt{K}+a_{{\rm max}},\sqrt{K}+a_{\rm {min}}\big )$, where amin and amax are the smallest and largest eigenvalues of the matrix A, we prove that for λ small the random Schrödinger operator Hλ has purely absolutely continuous spectrum in I with probability one and its integrated density of states is continuously differentiable on the interval I.  相似文献   
25.
The notion of D-simplicity is used to give a short proof that varieties whose normalization is smooth satisfy Ishibashi's extension of Nakai's conjecture to arbitrary characteristic. This gives a new proof of Nakai's conjecture for curves and Stanley-Reisner rings.

  相似文献   

26.
Entanglement as a vital resource for information processing can be described by special properties of the quantum state. Using the well-known Weyl basis we propose a new Bloch decomposition of the quantum state and study its separability problem. This decomposition enables us to find an alternative characterization of the separability based on the correlation matrix. We show that the criterion is effective in detecting entanglement for the isotropic states, Bell-diagonal states and some PPT entangled states. We also use the Weyl operators to construct an detecting operator for quantum teleportation.  相似文献   
27.
Abstract Let Ω R~m(m≥1)be a bounded domain with piecewise smooth boundary Ω.Let t and r bepositive integers with t>r+1. We consider the eigenvalue problems(1.1)and(12),and obtain Theorem 1and Theorem 2, which generalize the results in[1,2.5].  相似文献   
28.
Let be a compact set with interior G. Let L 1 (G,dx), >0 dx-a.e. on G, and m:=dx. Let A=(a ij ) be symmetric, and globally uniformly strictly elliptic on G. Let be such that ; f, , is closable in L 2 (G,m) with closure ( r ,D( r )). The latter is fulfilled if satisfies the Hamza type condition, or i L 1 loc (G,dx), 1id. Conservative, non-symmetric diffusion processes X t related to the extension of a generalized Dirichlet form where satisfies are constructed and analyzed. If G is a bounded Lipschitz domain, H 1,1 (G), and a ij D( r ), a Skorokhod decomposition for X t is given. This happens through a local time that is uniquely associated to the smooth measure 1{ Tr ()>0} d, where Tr denotes the trace and the surface measure on G.This research has been financially supported by TMR grant HPMF-CT-2000-00942 of the European Union. Mathematics Subject Classification (2000): 60J60, 60J55, 31C15, 31C25, 35J25  相似文献   
29.
gi.TheTOpologicalDegreeforGeneralizedMonotoneOperatorsMonotoneoperatortheoryisoftenanefficienttoolforprovingtheexistenceofsolutionstononlinearProblems.Inparticular,thepseudo-monotoneoperatorsintroducedbyBrezis[2]areveryusefulforstudyingnonlinearellipticproblems.Weconsiderherethefollowingclassesofmappingsofgeneralizedmonotonetype.(QM)=theclassofquasi-mollotoneoperators,(S )=theclassofoperatorsoftype(S ),(PM)=theclassofpseudthmonotoneoperators,(LS)=theclassofLeray-Schauderoperators(compac…  相似文献   
30.
混合单调算子的某些不动点定理与锥上的正不动点   总被引:2,自引:0,他引:2  
给出在半序距离空间以迭代而得到的某些不动点定理的混合单调算子和在锥上某些非零不动点定理。  相似文献   
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