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71.
Let R be a subring ring of Q. We reserve the symbol p for the least prime which is not a unit in R; if R ?Q, then p=∞. Denote by DGL n np , n≥1, the category of (n-1)-connected np-dimensional differential graded free Lie algebras over R. In [1] D. Anick has shown that there is a reasonable concept of homotopy in the category DGL n np . In this work we intend to answer the following two questions: Given an object (L(V), ?) in DGL n 3n+2 and denote by S(L(V), ?) the class of objects homotopy equivalent to (L(V), ?). How we can characterize a free dgl to belong to S(L(V), ?)? Fix an object (L(V), ?) in DGL n 3n+2 . How many homotopy equivalence classes of objects (L(W), δ) in DGL n 3n+2 such that H * (W, d′)?H * (V, d) are there? Note that DGL n 3n+2 is a subcategory of DGL n np when p>3. Our tool to address this problem is the exact sequence of Whitehead associated with a free dgl. 相似文献
72.
73.
J. Socorro 《International Journal of Theoretical Physics》2003,42(9):2087-2096
The quantization of gravity coupled to barotropic perfect fluid matter field with a cosmological constant is carried out. The wave function can be determined for any curvature index in the FRW minisuperspace model. The meaning of the existence of the classical solution is discussed in the WKB semiclassical approximation. 相似文献
74.
Suppose that
is an arbitrary finite complex Borel measure on the interval
is its Poisson integral,
and
are the conjugate harmonics of
, and
is the nontangential limiting value of the analytic function
as
. In this paper, we consider the problem of representing the analytic function
in terms of its boundary values
. 相似文献
75.
Let
be a sequence of complex numbers such that
as
. For
close to the imaginary axis, upper bounds of the indicator of a nonzero entire function of exponential type with minimal growth vanishing on
is obtained. These bounds give sufficient conditions for the system of exponents
to be incomplete in an unbounded domain in
. 相似文献
76.
In the assignment game framework, we try to identify those assignment matrices in which no entry can be increased without
changing the core of the game. These games will be called buyer-seller exact games and satisfy the condition that each mixed-pair
coalition attains the corresponding matrix entry in the core of the game. For a given assignment game, a unique buyer-seller
exact assignment game with the same core is proved to exist. In order to identify this matrix and to provide a characterization
of those assignment games which are buyer-seller exact in terms of the assignment matrix, attainable upper and lower core
bounds for the mixed-pair coalitions are found. As a consequence, an open question posed in Quint (1991) regarding a canonical
representation of a “45o-lattice” by means of the core of an assignment game can now be answered.
Received: March 2002/Revised version: January 2003
RID="*"
ID="*" Institutional support from research grants BEC 2002-00642 and SGR2001-0029 is gratefully acknowledged
RID="**"
ID="**" The authors thank the referees for their comments 相似文献
77.
Consider an n-person stochastic game with Borel state space S, compact metric action sets A
1,A
2,,A
n
, and law of motion q such that the integral under q of every bounded Borel measurable function depends measurably on the initial state x and continuously on the actions (a
1,a
2,,a
n
) of the players. If the payoff to each player i is 1 or 0 according to whether or not the stochastic process of states stays forever in a given Borel set G
i
, then there is an -equilibrium for every >0.
AMS (1991) subject classification: 60G40, 91A60, 60E15, 46A55. 相似文献
78.
The paper is concerned with a recent very interesting theorem obtained by Holický and Zelený. We provide an alternative proof avoiding games used by Holický and Zelený and give some generalizations to the case of set-valued mappings. 相似文献
79.
We show that with the weak topology is not an intersection of Borel sets in its Cech-Stone extension (and hence in any compactification). Assuming (CH), this implies that has no continuous injection onto a Borel set in a compact space, or onto a Lindelöf space. Under (CH), this answers a question of Arhangel'ski.
80.
Piotr Zakrzewski 《Proceedings of the American Mathematical Society》2001,129(6):1793-1798
We study category counterparts of the notion of a universal measure zero set of reals.
We say that a set is universally meager if every Borel isomorphic image of is meager in . We give various equivalent definitions emphasizing analogies with the universally null sets of reals.
In particular, two problems emerging from an earlier work of Grzegorek are solved.