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Eliana Zoque

Publications and source records attributed to Eliana Zoque.

4 recordsLinked to original sources

Partitions, pairs of trees and Catalan numbers

In "Square partitions and Catalan numbers" (arXiv0912.4983), Bennett et al. presented a recursive algorithm to create a family of partitions from one or several partitions. They were mainly interested in the cases when we begin with a single square partition or with several partitions with only one part. The cardinalities of those families of partitions are the Catalan and ballot numbers, respectively. In this paper we present a closed description for those families. We also present bijections between those sets of partitions and sets of trees and forests enumerated by the Catalan an ballot numbers.

math.CO↗

On the variety of almost commuting nilpotent matrices

We study the variety of n by n matrices with commutator of rank at most one. We describe its irreducible components; two of them correspond to the pairs of commuting matrices, and n-2 components of smaller dimension corresponding to the pairs of rank one commutator. In our proof we define a map to the zero fiber of the Hilbert scheme of points and study the image and the fibers.

math.RT↗

A counterexample to the existence of a Poisson structure on a twisted group algebra

Crawley-Boevey introduced the definition of a noncommutative Poisson structure on an associative algebra A that extends the notion of the usual Poisson bracket. Let V be a symplectic manifold and G be a finite group of symplectimorphisms of V. Consider the twisted group algebra A=C[V]#G. We produce a counterexample to prove that it is not always possible to define a noncommutative poisson structure on C[V]#G that extends the Poisson bracket on C[V]^G.

math.QA↗