Cohomologie de Chevalley des graphes ascendants

The space $T_{poly}(\mathbb R^d)$ of all tensor fields on $\mathbb R^d$, equipped with the Schouten bracket is a Lie algebra. The subspace of ascending tensors is a Lie subalgebra of $T_{poly}(\mathbb R^d)$. In this paper, we compute the cohomology of the adjoint representations of this algebra (in itself and $T_{poly}(\mathbb R^d)$), when we restrict ourselves to cochains defined by aerial Kontsevitch's graphs like in our previous work (Pacific J of Math, vol 229, no 2, (2007) 257-292). As in the vectorial graphs case, the cohomology is freely generated by all the products of odd wheels

Hom-Lie quadratic and Pinczon Algebras

International audienc

Algèbres pré-Gerstenhaber à homotopie près

This paper is concerned by the concept of algebra up to homotopy for a structure defined by two operations $.$ and $[~,~]$. An important example of such a structure is the Gerstenhaber algebra (commutatitve and Lie). The notion of Gerstenhaber algebra up to homotopy ($G_\infty$ algebra) is known. Here, we give a definition of pre-Gerstenhaber algebra (pre-commutative and pre-Lie) allowing the construction of $\hbox{pre}G_\infty$ algebra. Given a structure of pre-commutative (Zinbiel) and pre-Lie algebra and working over the corresponding dual operads, we will give an explicit construction of the associated pre-Gerstenhaber algebra up to homotopy, this is a bicogebra (Leibniz and permutative) equipped with a codifferential which is a coderivation for the two coproducts

Algèbre Pré-Gerstenhaber à homotopie près

International audienceRésumé. On étudie le concept d'algèbre à homotopie près pour une structure définie par deux opérations . et [ , ]. Un exemple important d'une telle structure est celui d'algèbre de Gerstenhaber (avec une structure commutative de degré 0 et une structure de Lie de degré −1). La notion d'algèbre de Gerstenhaber à homotopie près (G∞ algèbre) est connue : c'est une bicogèbre codifférentielle.Ici nous proposons une définition d'algèbre pré-Gerstenhaber (pré-commutative et pré-Lie) permettant la construction similaire d'une preG∞ algèbre.Partant d'une structure pré-commutative (Zinbiel) et pré-Lie, on utilise les opérades duales correspondantes, qui sont de Koszul. Nous donnons la construction explicite de l'algèbre à homotopie près associée. Celle-ci est une bicogèbre (Leibniz et permutative), munie d'une codifférentielle qui est une codérivation des deux coproduits.Abstract. This paper is concerned by the concept of algebra up to homotopy for a structure defined by two operations . and [ , ]. An important example of such a structure is the Gerstenhaber algebra (i.e. commutatitve structure with degree 0 and Lie structure with degree −1). The notion of Gerstenhaber algebra up to homotopy (G∞ algebra) is known: it is a codifferential bicogebra.Here, we give a definition of pre-Gerstenhaber algebra (pre-commutative and pre-Lie) allowing a similar construction for a preG∞ algebra.Given a structure of pre-commutative (Zinbiel) and pre-Lie algebra and working over the corresponding Koszul dual operads, we will give an explicit construction of the associated pre-Gerstenhaber algebra up to homotopy: it is a bicogebra (Leibniz and permutative) equipped with a codifferential which is a coderivation for the two coproducts

Algèbres et cogèbres de Gerstenhaber et cohomologie de Chevalley-Harrison

The fundamental example of Gerstenhaber algebra is the space $T_{poly}({\mathbb R}^d)$ of polyvector fields on $\mathbb{R}^d$, equipped with the wedge product and the Schouten bracket. In this paper, we explicitely describe what is the enveloping $G_\infty$ algebra of a Gerstenhaber algebra $\mathcal{G}$. This structure gives us a definition of the Chevalley-Harrison cohomology operator for $\mathcal{G}$. We finally show the nontriviality of a Chevalley-Harrison cohomology group for a natural Gerstenhaber subalgebra in $T_{poly}({\mathbb R}^d)$