-groups.
algebras associated with von Neumann algebras
Ad un'algebra di von Neumann separabile , in forma standard su di uno spazio di Hilbert , si associa la algebra definita come la algebra costituita dai punti fissi dell'algebra di Cuntz generalizzata mediante l'azione canonica del gruppo degli unitari di . Si dà una caratterizzazione di nel caso in cui è un fattore iniettivo. In seguito, come applicazione della teoria dei sistemi asintoticamente abeliani, si mostra che, se è uno stato vettoriale normale e fedele di , la restrizione...
C. N. Yang a současná matematika
-semipermutable subgroups of finite groups.
Cacti, braids and complex polynomials.
Calcul de la distance par les sous-mots
Calcul du centralisateur d'un groupe de permutations
Calcul sur ordinateur de demi-groupes finis de transformations
Calculating canonical distinguished involutions in the affine Weyl groups.
Calculating the genus of a direct product of certain nilpotent groups.
The Mislin genus G(N) of a finitely generated nilpotent group N with finite commutator subgroup admits an abelian group structure. If N satisfies some additional conditions -we say that N belongs to N1- we know exactly the structure of G(N). Considering a direct product N1 x ... x Nk of groups in N1 takes us virtually always out of N1. We here calculate the Mislin genus of such a direct product.
Calculation of Baer-invariant of Certain Groups.
Calculs d'invariants primitifs de groupes finis
Calculs d'invariants primitifs de groupes finis
We introduce in this article a new method to calculate all absolute and relatif primitive invariants of finite groups. This method is inspired from K. Girstmair which calculate an absolute primitive invariant of minimal degree. Are presented two algorithms, the first one enable us to calculate all primitive invariants of minimal degree, and the second one calculate all absolute or relative primitive invariants with distincts coefficients. This work take place in Galois Theory and Invariant Theory. ...
Cambrian fans
For a finite Coxeter group and a Coxeter element of ; the -Cambrian fan is a coarsening of the fan defined by the reflecting hyperplanes of . Its maximal cones are naturally indexed by the -sortable elements of . The main result of this paper is that the known bijection cl between -sortable elements and -clusters induces a combinatorial isomorphism of fans. In particular, the -Cambrian fan is combinatorially isomorphic to the normal fan of the generalized associahedron for . The rays...
Cancellation law for Homotopy Equivalent representations of Groups of odd order.
Cancellation of Abelian groups of finite rank modulo elementary equivalence.
Cancellative actions
The following problem is considered: when can the action of a cancellative semigroup on a set be extended to a simply transitive action of the universal group of on a larger set.
Cancellative and archimedean Ideal-extensions by commutative semigroups.
Cancellative commutative semigroups.
Cancellative relations and matrices