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1.
We conclude the construction of the algebraic complex, consisting of spaces of differentials of Euclidean metric values, for four-dimensional piecewise-linear manifolds. Assuming that the complex is acyclic, we investigate how its torsion changes under rebuildings of the manifold triangulation. We first write formulas for moves 33 and 24 based on the results in our two previous works and then study moves 15 in detail. Based on this, we obtain the formula for a four-dimensional manifold invariant. As an example, we present a detailed calculation of our invariant for the sphere S 4; in particular, the complex does turn out to be acyclic.  相似文献   

2.
If A and B are operators in the spaces X and Y, respectively, and if the operator B has many sets , , such that the manifolds p is a polynomial are dense in the space Y, then Here a=(the multiplicity of the spectrum of the operator A)=mindimL: span (AnL:n0)}=X. For example, if B=Tg is a Toeplitz operator in the space H2 with antianalytic symbol) and if g (the polynomial convex hull of the spectrum (A)) , then. Conversely, if and, then (under some assumptions on the regularity of the function f we have. One also gives examples of univalent and essentially univalent functions f (f H), for which Tf>1.Translated from Zapiski Nauchnykh Seminarov Leningradskogo Otdeleniya Matematicheskogo Instituta im. V. A. Steklova AN SSSR, Vol. 126, pp. 150–158, 1983.  相似文献   

3.
Summary Consider a random walk of law on a locally compact second countable groupG. Let the starting measure be equivalent to the Haar measure and denote byQ the corresponding Markov measure on the space of pathsG . We study the relation between the spacesL (G , a ,Q) andL (G , i ,Q) where a and i stand for the asymptotic and invariant -algebras, respectively. We obtain a factorizationL (G , a ,Q) L (G , i ,Q)L (C) whereC is a cyclic group whose order (finite or infinite) coincides with the period of the Markov shift and is determined by the asymptotic behaviour of the convolution powers n.  相似文献   

4.
The independent domination number i(G) (independent number (G)) is the minimum (maximum) cardinality among all maximal independent sets of G. Haviland (1995) conjectured that any connected regular graph G of order n and degree 1/2n satisfies i(G) 2n/3 1/2. For 1 k l m, the subset graph S m (k, l) is the bipartite graph whose vertices are the k- and l-subsets of an m element ground set where two vertices are adjacent if and only if one subset is contained in the other. In this paper, we give a sharp upper bound for i(S m (k, l)) and prove that if k + l = m then Havilands conjecture holds for the subset graph S m (k, l). Furthermore, we give the exact value of (S m (k, l)).This work was supported by National Natural Sciences Foundation of China (19871036).  相似文献   

5.
An A n k -polyhedron is a CW-complex which is (n–1)-connected and of dimension (n+k). We compute an algebraic category which is equivalent to the homotopy category of A n 2 -polyhedra with free homology (n3). This computation and a calculation of the -group n+3(X) (n3) is used to obtain a complete algebraic homotopy invariant for A n 4 -polyhedra with free homology (n3).As an application we compute the group of self-homotopy equivalences Aut(X) for a bouquet X=P2.  相似文献   

6.
Let G be a finite permutation group on a set with no fixed points in and let m and k be integers with 0 < m < k. For a finite subset of the movement of is defined as move() = maxgG| g \ |. Suppose further that G is not a 2-group and that p is the least odd prime dividing |G| and move() m for all k-element subsets of . Then either || k + m or k (7m – 5) / 2, || (9m – 3)/2. Moreover when || > k + m, then move() m for every subset of .  相似文献   

7.
Shikata proved: there is a number (n) with the following property: If two compact homeomorphic n-dimensional manifolds have a distance less than (n), then they are diffeomorphic. We improve the known lower bound (n!)–n for (n) to 1/3n –2.This work was done under the program Sonderforschungsbereich Theoretische Mathematik (SFB 40) at Bonn University while Shikata was SFB-guest at Bonn.  相似文献   

8.
Let X be a nilpotent space such that it exists k1 with Hp (X,) = 0 p > k and Hk (X,) 0, let Y be a (m–1)-connected space with mk+2, then the rational homotopy Lie algebra of YX (resp. is isomorphic as Lie algebra, to H* (X,) (* (Y) ) (resp.+ (X,) (* (Y) )). If X is formal and Y -formal, then the spaces YX and are -formal. Furthermore, if dim * (Y) is infinite and dim H* (Y,Q) is finite, then the sequence of Betti numbers of grows exponentially.  相似文献   

9.
Let (X,) be a separable -finite measure space. A bounded operator A on L2(X) is called an integral operator if it is induced by an equation: Af(x) = k(x,y)f(y)d(y), where k is a measurable function on X × X such that |k(x,y)f(y)|d(y) < a.e. for every f in L2(X).In this paper, some results on Carleman operators, due to von Neumann, Tarjonski and Weidmann, are extended to the case of the general integral operator.  相似文献   

10.
In this paper we formulate a theory of noncommutative manifolds (quantum manifolds) and for such manifolds we develop a geometric theory of quantum PDEs (QPDEs). In particular, a criterion of formal integrability is given that extends to QPDEs previously obtained by D. C. Spencer and H. Goldschmidt for PDEs for commutative manifolds, and by Prástaro for super PDEs. Quantum manifolds are seen as locally convex manifolds where the model has the structure A m 1 1×···×A m s s , with AA 1×···×A s a noncommutative algebra that satisfies some particular axioms (quantum algebra). A general theory of integral (co)bordism for QPDEs is developed that extends our previous for PDEs. Then, noncommutative Hopf algebras (full quantum p-Hopf algebras, 0pm–1) are canonically associated to any QPDE, Êk k m(W) whose elements represent all the possible invariants that can be recognized for such a structure. Many examples of QPDEs are considered where we apply our theory. In particular, we carefully study QPDEs for quantum field theory and quantum supergravity. We show that the corresponding regular solutions, observed by means of quantum relativistic frames, give curvature, torsion, gravitino and electromagnetic fields as A-valued distributions on spacetime, where A is a quantum algebra. For such equations, canonical quantizations are obtained and the quantum and integral bordism groups and the full quantum p-Hopf algebras, 0p3, are explicitly calculated. Then, the existence of (quantum) tunnel effects for quantum superstrings in supergravity is proved.  相似文献   

11.
12.
We define a subdivision functor G for semisimplicial sets such that GXGY implies XY for all pairs of semisimplicial sets X, Y and (GX)1(GY)1 implies XY, too, but only, as far as we know, for pairs of weakly degenerate semisimplicial sets X, Y. These results are analogous to theorems on simplicial complexes which have been proved by Finney [1] and Segal [6].

In der Literatur werden semisimpliziale Mengen auch oft als complete semisimplicial complexes, abgekürzt css complexes bezeichnet. Wir halten uns hier im wesentlichen an die Terminologie von K. Lamotke [5].  相似文献   

13.
This paper presents several new algorithms, generalizing feasible directions algorithms, for the nonlinear programming problem, min{f 0 (z) f j (z) 0,j = 1, 2, ,m}. These new algorithms do not require an initial feasible point. They automatically combine the operations of initialization (phase I) and optimization (phase II).Research sponsored by the National Science Foundation (RANN) Grant ENV76-04264 and the National Science Foundation Grant ENG73-08214-A01.  相似文献   

14.
Let R be an associative, commutative, unital ring. By a R-algebra we mean a unital R-module A together with a R-module homomorphism : R n AA (n2). We raise the question whether such an algebra possesses either an idempotent or a nilpotent element. In section 1 an affirmative answer is obtained in case R=k is an algebraically closed field and dimkA<, as well as in case R=, dimS<, and n0(2). Section 2 deals with the case of reduced rings R and R-algebras which are finitely generated and projective as R-modules. In section 3 we show that the generic algebra over an integral domain D fails to have nilpotent elements in any integral domain extending its base ring Dn,m, and thus acquires an idempotent element in some integral domain extending Dn,m.Partially supported by National Science Foundation Grant GP-38229.  相似文献   

15.
We obtain the analytic expression for the total cross section of the reaction e e +l l + (l=,) taking possible quasianapole interaction effects into account. We find numerical restrictions on the interaction parameter value from data for the reaction e e ++ in the energy domain below the Z 0 peak.  相似文献   

16.
Casazza  P.G.  Nielsen  N.J. 《Positivity》2001,5(4):297-321
In this paper we first show that if X is a Banach space and is a left invariant crossnorm on lX, then there is a Banach lattice L and an isometric embedding J of X into L, so that I J becomes an isometry of lX onto lm J(X). Here I denotes the identity operator on l and lm J(X) the canonical lattice tensor product. This result is originally due to G. Pisier (unpublished), but our proof is different. We then use this to prove the main results which characterize the Gordon–Lewis property GL and related structures in terms of embeddings into Banach lattices.  相似文献   

17.
Let k denote a non-trivial non-archimedean complete valuated field and X an irreducible k-affinoid space. We discuss the Hartog's domain H*:=(X×En) (U×En) where øUX is an affinoid subdomain, En is the n-dimensional unit-polydisc over k and En is the ringdomain of all z==(z1,...,zn)En with some coordinate |zi|=1. The main result is the non-archimedean version of Rothstein's extensiontheorem for analytic subvarieties: Every k-holomorphic subvariety AH* whose every branch has dimension (dim X + 1) can be extended to a k-holomorphic subvariety X×En such that every branch of has dimension (dim X + l).  相似文献   

18.
We study CR submanifolds M in a Hopf manifold (C H N (), J 0, g 0) with the Boothby metric g 0,of maximal CR dimension. Any such M is a CR manifold ofhypersurface type, although embedded in higher codimension, and itsanti-invariant distribution H(M) is spanned by a unit vectorfield U. We classify the CR submanifolds M for which = –J 0 Uis parallel in the normal bundle under assumptions on thespectrum of the Weingarten operator a . We show that (1) ifa (U) = (1/2)A (where A is the anti-Lee vector) andM fibres in tori over a CR submanifold of the complex projectivespace, then M lies on the (total space of the) pullback of the Hopf fibration via S C P N – 1, for some geodesic hypersphere S, and (2) if a (U)= 0 and Spec(a ) = {0, c}, for some c R {0}, then M is locally a Riemannian product of totally geodesicsubmanifolds.  相似文献   

19.
We give efficiency estimates for proximal bundle methods for finding f*minXf, where f and X are convex. We show that, for any accuracy <0, these methods find a point xkX such that f(xk)–f* after at most k=O(1/3) objective and subgradient evaluations.  相似文献   

20.
Pair algebras which have a non degenerate (left- and right-) invariant bilinear form and for which the inner derivation algebra is completely reducible are characterised by pairs (C,), where C is a n×n matrix satisfying certain conditions and is a sequence of n integers equal to 0 or 1. They occur as pair algebras of type (S(C,)–1,S(C,)1), xuy=[[x,u],y], where (S(C,)r)r is the gradation induced by . in the Kac-Moody algebraS(C). If C is an affin Cartan matrix (as in the case of Lie triple systems), there exists a finite dimensional simple Lie algebrag and a Aut (g), ord =m< such that the pair algebra is isomorphic to the pair algebra (g –1,g 1), xuy=[[x,u],y] (product ing), whereg i. is the eigenspace of of eigenvalue i, a primitive m-th root of unity.  相似文献   

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