arXiv subjects
Publications and source records attributed to Dominique Manchon.
We investigate here the confluence of singularities of Mathieu differential equation by means of the Lie algebra contraction of the Lie algebra of the motion group M(2) on the Heisenberg Lie algebra H(3). A similar approach for the Lamé equation in terms of the Lie algebra contraction of $SO_0(2,1)$ on the Lie algebra of the motion group M(2) is outlined.
We investigate solutions for a particular class of linear equations in dendriform algebras. Motivations as well as several applications are provided. The latter follow naturally from the intimate link between dendriform algebras and Rota-Baxter operators, e.g. the Riemann integral or Jackson's q-integral.
We provide a refined approach to the classical Magnus and Fer expansion, unveiling a new structure by using the language of dendriform and pre-Lie algebras. The recursive formula for the logarithm of the solutions of the equations X=1+ta a in A[[t]] is provided, where (A,<,>) is a dendriform algebra. Then, we present the solutions to these equations as an infinite product expansion of exponentials. Both formulae involve the pre-Lie product naturally associated with the dendriform structure. Several applications are presented.
Dendriform structures arise naturally in algebraic combinatorics (where they allow, for example, the splitting of the shuffle product into two pieces) and through Rota-Baxter algebra structures (the latter appear, among others, in differential systems and in the renormalization process of pQFT). We prove new combinatorial identities in dendriform dialgebras that appear to be strongly related to classical phenomena, such as the combinatorics of Lyndon words, rewriting rules in Lie algebras, or the fine structure of the Malvenuto-Reutenauer algebra. One of these identities is an abstract noncommutative, dendriform, generalization of the Bohnenblust-Spitzer identity and of an identity involving iterated Chen integrals due to C.S. Lam.
This paper has been withdrawn as it is superseded by the new version math.NT/0702135 in which two major problems (non-compatibility of the regularisation with the stuffle product and incorrect higher-dimensional setting) are fixed.
We establish Sakakibara's differential equations in a matrix setting for the counter term (respectively renormalized character) in Connes-Kreimer's Birkhoff decomposition in any connected graded Hopf algebra, thus including Feynman rules in perturbative renormalization as a key example.
The Wodzicki residue and the cut-off integral extend to classical symbol-valued forms. We show that they obey a Stokes' type property and that the extended Wodzicki residue can be interpreted as a complex residue like the ordinary one. In the case of cut-off integrals, Stokes' property (i.e. vanishing on exact forms) only holds for non-integer order symbol-valued forms and leads to an integration by parts formula and translation invariance for cut-off integrals on non-integer order classical symbols. The extended Wodzicki residue yields an even residue cycle on classical symbols and an odd cochain (the cosphere cochain) which measures an obstruction to Stokes' property of the cut-off integral on integer order symbol-valued forms.
An extended version of a series of lectures given at Bogota in december 2002. It consists in a presentation of some aspects of Connes' and Kreimer's work on renormalization in the context of general connected Hopf algebras, in particular Birkhoff decomposition and, in the graded case, the scattering-type formula.
We prove shuffle relations which relate a product of regularised integrals of classical symbols to regularised nested (Chen) iterated integrals, which hold if all the symbols involved have non-vanishing residue. This is true in particular for non-integer order symbols. In general the shuffle relations hold up to finite parts of corrective terms arising from renormalisation on tensor products of classical symbols, a procedure adapted from renormalisation procedures on Feynman diagrams familiar to physicists. We relate the shuffle relations for regularised integrals of symbols with shuffle relations for multizeta functions adapting the above constructions to the case of symbols on the unit circle.
This paper has been withdrawn by the authors, as it contains some errors. The core of it has been entirely rewritten in math.FA/0510454.
The purpose of the present work is to describe a dequantization procedure for topological modules over a deformed algebra. We define the characteristic variety of a topological module as the common zeroes of the annihilator of the representation obtained by setting the deformation parameter to zero. On the other hand, the Poisson characteristic variety is defined as the common zeroes of the ideal obtained by considering the annihilator of the deformed representation, and only then setting the deformation parameter to zero. Using Gabber's theorem, we show the involutivity of the characteristic variety. The Poisson characteristic variety is indeed a Poisson subvariety of the underlying Poisson manifold. We compute explicitly the characteristic variety in several examples in the Poisson-linear case, including the dual of any exponential solvable Lie algebra. In the nilpotent case, we show that any coadjoint orbit appears as the Poisson characteristic variety of a well chosen topological module.
On a flat manifold, M. Kontsevich's formality quasi-isomorphism is compatible with cup-products on tangent cohomology spaces, in the sense that its derivative at any formal Poisson 2-tensor induces an isomorphism of graded commutative algebras from Poisson cohomology space to Hochschild cohomology space relative to the associated deformed multiplication. We give here a detailed proof of this result, with signs and orientations precised.
We express the difference between Poisson bracket and deformed bracket for Kontsevich deformation quantization on any Poisson manifold by means of second derivative of the formality quasi-isomorphism. The counterpart on star products of the action of formal diffeomorphisms on Poisson formal bivector fields is also investigated.
Nous definissons le front d'onde d'un vecteur-distribution pour une representation unitaire d'un groupe de Lie reel $G$ a l'aide du calcul pseudo-differentiel mis au point dans un travail anterieur. Cette notion precise celle de front d'onde d'une representation introduite par R. Howe. En application nous donnons une condition suffisante pour qu'un vecteur-distribution reste un vecteur-distribution pour la restriction de la representation a un sous-groupe ferme $H$, et nous donnons un theoreme de propagation des singularites pour les vecteurs-distribution.
Dans cet article nous precisons les notions de representations unitaires fortement tracables et de front d'onde d'une representation unitaire, toutes deux introduites par Roger Howe. Nous montrons que pour toute distribution $ϕ$ a support compact sur un groupe de Lie connexe dont le front d'onde ne rencontre pas l'oppose du front d'onde de la representation $π$ l'operateur $π(ϕ)$ est regularisant. De plus, sous les memes hypotheses cet operateur est a trace si la representation est fortement tracable. Dans le cas ou la representation est irreductible et associee par la methode des orbites a une orbite fermee et temperee, nous montrons qu'elle est fortement tracable et nous etendons la formule des caracteres aux operateurs $π(ϕ)$ pour les distributions $ϕ$ a support compact dont le front d'onde verifie la condition de transversalite ci-dessus.
Nous construisons pour tout corps k de caracteristique zero un foncteur de la categorie des k-espaces vectoriels dans la categorie des k-algebres de Hopf pointees, qui a tout espace vectoriel V associe son algebre de Hopf bitensorielle pointee A(V). Cette algebre de Hopf est graduee, verifie une propriete universelle, et contient une famille remarquable d'elements primitifs P. Nous conjecturons que P engendre l'algebre de Lie des elements primitifs de A(V). Enfin lorsque V est de dimension finie nous mettons en evidence un couplage de Hopf entre A(V) et A(V*) dont le noyau contient l'ideal (de Hopf) engendre par les elements de P de degre au moins egal a 2.