Christophe Tollu
Current Organizations / Institutes
The organizations/institutes from the scholar's latest article
Research Subjects
Research Interests
Christophe Tollu has a total of 12 co-authors. Here are the top co-authors by number of shared publications:
- Gerard Henry Edmond Duchamp
Institut Galilée UMR CNRS 7030
2 shared publications - Gérard Henry Edmond Duchamp
LIPN Northen Paris University Sorbonne Paris City 93430 Villetaneuse France
2 shared publications - Jean-Gabriel Luque
Institut Gaspard Monge Université de Marne-la-Vallée 77454 Marne-la-Vallée cedex France
2 shared publications Edmond Duchamp
1 shared publication- Frederic Toumazet
Laboratoire d'Informatique de Paris Nord, Institut Galilée-Université Paris 13/Paris Nord, 99 av. J.-B. Clement 93430 Villetaneuse, France
1 shared publication Gérard Henry
1 shared publication
Latest Publications
- Open Access
Elementary methods for splitting representations of Rook monoids: a gentle introduction to groupoids
We show that the algebra of the coloured rook monoid $R_n^{(r)}$, {\em i.e.} the monoid of $n \times n$ matrices with at most one non-zero entry (an $r$-th root of unity) in each column and row, is the algebra of a finite groupoid, thus is endowed with a $C^*$-algebra structure. This new perspective uncovers the representation theory of these monoid algebras by making manifest their decomposition in irreducible modules.Open AccessElementary methods for splitting representations of Rook monoids: a gentle introduction to groupoids
We show that the algebra of the coloured rook monoid $R_n^{(r)}$, {\em i.e.} the monoid of $n \times n$ matrices with at most one non-zero entry (an $r$-th root of unity) in each column and row, is the algebra of a finite groupoid, thus is endowed with a $C^*$-algebra structure. This new perspective uncovers the representation theory of these monoid algebras by making manifest their decomposition in irreducible modules. - Open Access
About enveloping algebras of direct sums.
We solve the PBW-like problem of normal ordering for enveloping algebras of direct sums.
Open AccessAbout enveloping algebras of direct sums.
We solve the PBW-like problem of normal ordering for enveloping algebras of direct sums.
- Open Access
Hopf algebras of diagrams
We investigate several Hopf algebras of diagrams related to Quantum Field Theory of Partitions and whose product comes from the Hopf algebras WSym or WQSym respectively built on integer set partitions and set compositions. Bases of these algebras are indexed either by bipartite graphs (labelled or unlabbeled) or by packed matrices (with integer or set coefficients). Realizations on biword are exhibited, and it is shown how these algebras fit into a commutative diagram. Hopf deformations and dendriform structures are also considered for some algebras in the picture.
Open AccessHopf algebras of diagrams
We investigate several Hopf algebras of diagrams related to Quantum Field Theory of Partitions and whose product comes from the Hopf algebras WSym or WQSym respectively built on integer set partitions and set compositions. Bases of these algebras are indexed either by bipartite graphs (labelled or unlabbeled) or by packed matrices (with integer or set coefficients). Realizations on biword are exhibited, and it is shown how these algebras fit into a commutative diagram. Hopf deformations and dendriform structures are also considered for some algebras in the picture.
- Open Access
Free quasi-symmetric functions, product actions and quantum field theory of partitions
We examine two associative products over the ring of symmetric functions related to the intransitive and Cartesian products of permutation groups. As an application, we give an enumeration of some Feynman type diagrams arising in Bender's QFT of partitions. We end by exploring possibilities to construct noncommutative analogues.
Open AccessFree quasi-symmetric functions, product actions and quantum field theory of partitions
We examine two associative products over the ring of symmetric functions related to the intransitive and Cartesian products of permutation groups. As an application, we give an enumeration of some Feynman type diagrams arising in Bender's QFT of partitions. We end by exploring possibilities to construct noncommutative analogues.
- 1 September 1995
- Published by Elsevier in Theoretical Computer Science
- Vol. 149 (1) , 67-99
On the expressive power of counting
- 1 September 1995
- Published by Elsevier in Theoretical Computer Science
- Vol. 149 (1) , 67-99
On the expressive power of counting