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Artículo
Ordering pure braid groups on compact, connected surfaces
(University of California, 2002-04)
We prove that the pure braid groups on compact, connected, orientable surfaces are bi-orderable, and that the pure braid groups on compact, connected non-orientable surfaces have generalized torsion, thus they are not ...
Artículo
Vassiliev invariants for braids on surfaces
(American Mathematical Society, 2004)
We show that Vassiliev invariants separate braids on a closed oriented surface, and we exhibit an universal Vassiliev invariant for these braids in terms of chord diagrams labeled by elements of the fundamental group of ...
Artículo
Presentations for the monoids of singular braids on closed surfaces
(Taylor & Francis, 2002)
We give presentations, in terms of generators and relations, for the monoids SBn(M) of singular braids on closed surfaces. The proof of the validity of these presentations can also be applied to verify, in a new way, the ...
Artículo
Conservation of the noetherianity by perfect transcendental field extensions
(European Mathematical Society, 2003)
Let k be a perfect field of characteristic p>0, k(t)per the perfect closure of k(t) and A a k-algebra. We characterize whether the ring A⊗kk(t)per is noetherian when A is the ring of formal power series in n indeterminates over k.
Artículo
Gröbner δ-bases and Gröbner bases for differential operators
(Polish Academy of Sciences, Institute of Mathematics, 2002)
This paper deals with the notion of Gr¨obner δ-base for some rings of linear differential operators by adapting the works of W. Trinks, A. Assi, M. Insa and F. Pauer. We compare this notion with the one of Gröbner base for ...
Artículo
Free divisors and duality for D-modules
(Pleiades, 2002)
The relationship between D-modules and free divisors has been studied in a general setting by L. Narváez and F.J. Calderón. Using the ideas of these works we prove in this article a duality formula between two D-modules ...