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31.
We introduce the notion of n-fold track extensions of a category C by a natural system D and prove that such extensions represent classes in the cohomology of C with coefficients in D introduced by Baues–Wirsching. This generalizes a result of Huebschmann on the cohomology of groups. 相似文献
32.
Hiroyuki Uesaka Chooichiro Asano 《Annals of the Institute of Statistical Mathematics》1987,39(1):513-531
Summary The purpose of the present paper is to propose an analytical method for ordered categorical responses obtained from a repeated
measurement/longitudinal experiment. The ordered categorical scale is assumed to be a manifestation of a latent quantitative
variable. A linear model is assumed for location parameters of the underlying distributions. Weighted least square method
is applied to parameter estimation and subsequent analysis. Two data sets are analyzed to show several aspects of analysis
by the proposed model and to discuss comparative characteristics of analysis compared with earlier analysis. A mention is
made for a computer software program for the proposed model. 相似文献
33.
D. Visetti 《Journal of Differential Equations》2008,245(9):2397-2439
The relation between the number of solutions of a nonlinear equation on a Riemannian manifold and the topology of the manifold itself is studied. The technique is based on Ljusternik-Schnirelmann category and Morse theory. 相似文献
34.
Let A and H be Hopf algebra,T-smash product A (∞)T H generalizes twisted smash product A*H.This paper shows a necessary and sufficient condition for T-smash product module category A(∞)T H M to be braided monoidal category. 相似文献
35.
C. Weibel 《Selecta Mathematica, New Series》2001,7(4):533-564
No Abstract. 相似文献
36.
J. C. Gómez-Larrañaga F. González-Acuña Wolfgang Heil 《Mathematische Zeitschrift》2008,259(2):419-432
A closed topological n-manifold M
n
is of S
1-category 2 if it can be covered by two open subsets W
1,W
2 such that the inclusions W
i
→ M
n
factor homotopically through maps W
i
→ S
1 → M
n
. We show that the fundamental group of such an n-manifold is a cyclic group or a free product of two cyclic groups with nontrivial amalgamation. In particular, if n = 3, the fundamental group is cyclic.
相似文献
37.
Yukinobu Toda 《Advances in Mathematics》2008,217(6):2736-2781
For a K3 surface X and its bounded derived category of coherent sheaves D(X), we have the notion of stability conditions on D(X) in the sense of T. Bridgeland. In this paper, we show that the moduli stack of semistable objects in D(X) with a fixed numerical class and a phase is represented by an Artin stack of finite type over C. Then following D. Joyce's work, we introduce the invariants counting semistable objects in D(X), and show that the invariants are independent of a choice of a stability condition. 相似文献
38.
WANG Shuanhong 《中国科学A辑(英文版)》2000,43(8):803-809
The central invariants of the derived ρ-Lie algebras in Yetter-Drinfeld categories are studied. 相似文献
39.
V. A. Smirnov 《Mathematical Notes》2005,78(1-2):251-257
Homotopy theories of algebras over operads, including operads over “little n-cubes,” are defined. Spectral sequences are constructed and the corresponding homotopy groups are calculated.__________Translated from Matematicheskie Zametki, vol. 78, no. 2, 2005, pp. 278–285.Original Russian Text Copyright © 2005 by V. A. Smirnov. 相似文献
40.
Let Y be a projective variety over a field k (of arbitrary characteristic). Assume that the normalization X of Y is such that is normal, being the algebraic closure of k. We define a notion of strong semistability for vector bundles on Y. We show that a vector bundle on Y is strongly semistable if and only if its pull back to X is strongly semistable and hence it is a tensor category. In case , we show that strongly semistable vector bundles on Y form a neutral Tannakian category. We define the holonomy group scheme of Y to be the Tannakian group scheme for this category. For a strongly semistable principal G‐bundle , we construct a holonomy group scheme. We show that if Y is an integral complex nodal curve, then the holonomy group of a strongly semistable vector bundle on Y is the Zariski closure of the (topological) fundamental group of Y. 相似文献