Search results for "algebra"

On saturated formations of finite groups with a restricted cover and avoidance property

1994

A rigidity theorem for Lagrangian deformations

2005

We consider deformations of singular Lagrangian varieties in symplectic manifolds. We prove that a Lagrangian deformation of a Lagrangian complete intersection is analytically rigid provided that this is the case infinitesimally. This result is given as a consequence of the coherence of the direct image sheaves of relative infinitesimal Lagrangian deformations.

Rejoinder on: Natural Induction: An Objective Bayesian Approach

2009

Giron and Moreno. We certainly agree with Professors Giron and Moreno on the interest in sensitivity of any Bayesian result to changes in the prior. That said, we also consider of considerable pragmatic importance to be able to single out a unique, particular prior which may reasonably be proposed as the reference prior for the problem under study, in the sense that the corresponding posterior of the quantity of interest could be routinely used in practice when no useful prior information is available or acceptable. This is precisely what we have tried to do for the twin problems of the rule of succession and the law of natural induction. The discussants consider the limiting binomial versi…

A Criterium for the Strict Positivity of the Density of the Law of a Poisson Process

2011

We translate in semigroup theory our result (Leandre, 1990) giving a necessary condition so that the law of a Markov process with jumps could have a strictly positive density. This result express, that we have to jump in a finite number of jumps in a "submersive" way from the starting point to the end point if the density of the jump process is strictly positive in . We use the Malliavin Calculus of Bismut type of (Leandre, (2008;2010)) translated in semi-group theory as a tool, and the interpretation in semi-group theory of some classical results of the stochastic analysis for Poisson process as, for instance, the formula giving the law of a compound Poisson process.

Extensions of hermitian linear functionals

2022

AbstractWe study, from a quite general point of view, the family of all extensions of a positive hermitian linear functional $$\omega $$ ω , defined on a dense *-subalgebra $${\mathfrak {A}}_0$$ A 0 of a topological *-algebra $${\mathfrak {A}}[\tau ]$$ A [ τ ] , with the aim of finding extensions that behave regularly. The sole constraint the extensions we are dealing with are required to satisfy is that their domain is a subspace of $$\overline{G(\omega )}$$ G ( ω ) ¯ , the closure of the graph of $$\omega $$ ω (these are the so-called slight extensions). The main results are two. The first is having characterized those elements of $${\mathfrak {A}}$$ A for which we can find a positive her…

Parallel fictitious domain method for a non‐linear elliptic neumann boundary value problem

1999

Parallelization of the algebraic fictitious domain method is considered for solving Neumann boundary value problems with variable coefficients. The resulting method is applied to the parallel solution of the subsonic full potential flow problem which is linearized by the Newton method. Good scalability of the method is demonstrated on a Cray T3E distributed memory parallel computer using MPI in communication. Copyright © 1999 John Wiley & Sons, Ltd.

Complex powers of elliptic pseudodifferential operators

1986

The aim of this paper is the construction of complex powers of elliptic pseudodifferential operators and the study of the analytic properties of the corresponding kernels kS (x,y). For x=y, the case of principal interest, the domain of holomorphy and the singularities of kS (x,x) are shown to depend on the asymptotic expansion of the symbol. For classical symbols, kS (x,x) is known to be meromorphic on ℂ with simple poles in a set of equidistant points on the real axis. In the more general cases considered here, the singularities may be distributed over a half plane and kS (x,x) can not always be extended to337-2. An example is given where kS (x,x) has a vertical line as natural boundary.

Real characters of p′-degree

2004

Endliche Gruppen, die eine Involution z besitzen, so daβ F∗(C(z)) das direkte Produkt einer extraspeziellen 2-Gruppe von kleiner Weite mit einer elem…

1980

Endliche einfache Gruppen mit einer zentralisatorgleichen elementar abelschen Untergruppe von der Ordnung 16

1977

Hierbei ist HiS die sporadische Higmar-Sims-Gruppe. Mit C, bezeichnen wir die dritte Conway-Gruppe. Die Gruppe He ist die in [l l] beschriebene sporadische einfache Gruppe. Eine Gruppe hat r(G) < 4, falls sich jede 2-Untergruppe von G mit hijchstens vier Elementen erzeugen IalIt. Zu den Gruppen mit Sylow 2-Untergruppe vom Typ A,, bzw. L,,(q) vergleiche [17]. Die Bezeichnungen folgen denen aus [4] und [17]. In [17] wurden Gruppen untersucht, die eine Untergruppe E mit / E 1 < 16 besitzten, so dal3 O,(No(E)/EC,(E)) = 1 ist. Zum Beweis von Satz A geniigt es also Gruppen zu untersuchen, in denen O,(No(E)/C,(E)E) # 1 ist. Da No(E) nicht auf&bar ist, ist weiter E elementar abelsch von der Ordnung…