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91.
Helge Glöckner 《manuscripta mathematica》1998,97(2):205-215
Let G be a p-adic Lie group. Then G is a locally compact, totally disconnected group, to which Willis [14] associates its scale function G : G→ℕ. We show that s can be computed on the Lie algebra level. The image of s consists of powers of p. If G is a linear algebraic group over ℚ
p
, s(x)=s(h) is determined by the semisimple part h of x∈G. For every finite extension K of ℚ
p
, the scale functions of G and H:=G(K) are related by s
H
∣
G
=s
G
[
K
:ℚ
p
]. More generally, we clarify the relations between the scale function of
a p-adic Lie group and the scale functions of its closed subgroups and Hausdorff quotients.
Received: 20 February 1997; Revised version: 18 May 1998 相似文献
92.
The aim of this work is to provide a combinatorial resolution of the local components of some automorphic forms of a general
linear group in a suitable way to realize them as transfer of packets of local components of square integrable automorphic
forms for classical groups. We obtain explicit transfer for Arthur’s packets. 相似文献
93.
L. Stoyanov 《Mathematische Annalen》2002,324(4):743-771
In this paper we consider properties of obstacles satisfying some non-degeneracy conditions that can be recovered from the
scattering length spectrum (SLS). Clearly the latter tells us whether the obstacle K is trapping or non-trapping. If the set of trapped points is relatively small, then the SLS also determines the volume of
the obstacle, the number of its connected components, and whether its boundary is convex everywhere or it has non-trivial
concavities. Under the additional assumption that the curvature of the obstacle does not vanish of infinite order, it is proved
that from the SLS one can recover certain information about the number of reflection points of any simply reflecting ray in
the exterior of the obstacle. Finally, for some special classes of obstacles (e.g. star-shaped ones), it is shown that the
SLS completely determines the obstacle.
Received: 2 March 1999 / Revised version: 16 January 2001 / Published online: 5 September 2002 相似文献
94.
All the symmetries and conservation laws of Navier-Stokes equations are calculated. 相似文献
95.
The first object of this paper is to introduce a new evolution equation for the characteristic function of the boundary Γ
of a Lipschitzian domain Ω in the N-dimensional Euclidean space under the influence of a smooth time-dependent velocity field. The originality of this equation is that the evolution takes place in an Lp-space with respect to the (N − 1)-Hausdorff measure. A second more speculative objective is to discuss how that equation can be relaxed to rougher velocity
fields via some weak formulation. A candidate is presented and some of the technical difficulties and open issues are discussed.
Continuity results in several metric topologies are also presented. The paper also specializes the results on the evolution
of the oriented distance function to initial sets with zero N-dimensional Lebesgue measure. 相似文献
96.
Armen Shirikyan 《Probability Theory and Related Fields》2006,134(2):215-247
We consider a class of dissipative PDE's perturbed by an external random force. Under the condition that the distribution
of perturbation is sufficiently non-degenerate, a strong law of large numbers (SLLN) and a central limit theorem (CLT) for
solutions are established and the corresponding rates of convergence are estimated. It is also shown that the estimates obtained
are close to being optimal. The proofs are based on the property of exponential mixing for the problem in question and some
abstract SLLN and CLT for mixing-type Markov processes. 相似文献
97.
98.
In this paper we prove the semialgebraic version of Palais' covering homotopy theorem, and use this to prove Bredon's covering mapping cylinder conjecture positively in the semialgebraic category. Bredon's conjecture was originally stated in the topological category, and a topological version of our semialgebraic proof of the conjecture answers the original topological conjecture for topological G-spaces over “simplicial” mapping cylinders. 相似文献
99.
应用改进的量子分子动力学模型,在严格挑选初始核考虑弹靶结构效应的基础上,研究了近垒和垒上融合反应40,48Ca+90,96Zr. 研究表明: 4个反应的理论计算截面与实验值很好符合; 丰中子反应40Ca+96Zr的垒下融合截面比其他3个反应有明显增强的现象.为了理解丰中子反应40Ca+96Zr与40Ca+90Zr相比垒下融合截面增强,而Ca+96Zr垒下融合截面没有明显增强的原因, 进一步分析了484个反应的融合位垒,中子转移与融合位垒的关系、中子转移与Q值的关系,结果表明: 正反应Q值会引起核子(特别是中子)转移的增强,从而导致动力学融合位垒的下降和垒下融合截面增强. 相似文献
100.
Yevhen Zelenyuk 《Topology and its Applications》2007,154(2):339-357
A topological space X is called almost maximal if it is without isolated points and for every x∈X, there are only finitely many ultrafilters on X converging to x. We associate with every countable regular homogeneous almost maximal space X a finite semigroup Ult(X) so that if X and Y are homeomorphic, Ult(X) and Ult(Y) are isomorphic. Semigroups Ult(X) are projectives in the category F of finite semigroups. These are bands decomposing into a certain chain of rectangular components. Under MA, for each projective S in F, there is a countable almost maximal topological group G with Ult(G) isomorphic to S. The existence of a countable almost maximal topological group cannot be established in ZFC. However, there are in ZFC countable regular homogeneous almost maximal spaces X with Ult(X) being a chain of idempotents. 相似文献