18 citations · 52 across the 18 of their papers we have counts for
22 papers
Quasi-complete intersections in P2 and syzygies
Philippe Ellia
Let C \in P2 be a reduced, singular curve of degree d and equation f = 0. Let Σdenote the jacobian subscheme of C. We have 0 -> E -> 3.O -> I_Σ(d-1) -> 0 (the surjection is given b…
Quasi complete intersections and global Tjurina number of plane curves
Philippe Ellia
A closed subscheme of codimension two is a quasi complete intersection (q.c.i.) of type if there exists a surjective morphism $\mathcal{O} (-a) \oplus \ma…
On the cohomology of rank two vector bundles on P2 and a theorem of Chiantini and Valabrega
Philippe Ellia
We show that a normalized rank two vector bundle, E, on P2 splits if and only if h1(E(-1)) = 0. Using this fact we give another proof of a theorem of Chiantini and Valabrega. Final…
The maximal genus of space curves in the range A
Edoardo Ballico, Philippe Ellia
Fix positive integers d;m such that (the so-called Range A for space curves). Let G(d;m) be the maximal genus of a smooth and connected curve,…
Maximal rank of space curves in the range A
Edoardo Ballico, Philippe Ellia, Claudio Fontanari
We prove the following statement, which has been conjectured since 1985: There exists a constant such that for all natural numbers with there exists an ir…
Spaces of matrices of constant rank and uniform vector bundles
Philippe Ellia, Paolo Menegatti
Let A be a k-vector space of dimension a. A subvector space M of End(A) is said to be of rank r if every non-zero f in M has rank r. The problem considered in this paper is to dete…