On zero-dimensional subschemes of a complete intersections.
Ngo Viet Trung, Giuseppe Valla (1995)
Mathematische Zeitschrift
Matthias Aschenbrenner, Wai Yan Pong (2004)
Fundamenta Mathematicae
We study the set of monomial ideals in a polynomial ring as an ordered set, with the ordering given by reverse inclusion. We give a short proof of the fact that every antichain of monomial ideals is finite. Then we investigate ordinal invariants for the complexity of this ordered set. In particular, we give an interpretation of the height function in terms of the Hilbert-Samuel polynomial, and we compute bounds on the maximal order type.
Ragusa, Alfio, Zappalà, Giuseppe (2003)
Beiträge zur Algebra und Geometrie
M.P. Cavaliere, M.E. Rossi, G. Valla (1995)
Mathematische Zeitschrift
R. Maggioni, A. Ragusa, S. Giuffrida (1996)
Manuscripta mathematica
Maria Virginia Catalisano, Anthony V. Geramita, Alessandro Gimigliano (2007)
Collectanea Mathematica
In this paper we compute the dimension of all the sth higher secant varieties of the Segre-Veronese embeddings Yd of the product P1 × P1 × P1 in the projective space PN via divisors of multidegree d = (a,b,c) (N = (a+1)(b+1)(c+1) - 1). We find that Yd has no deficient higher secant varieties, unless d = (2,2,2) and s = 7, or d = (2h,1,1) and s = 2h + 1, with defect 1 in both cases.
Roberto Sánchez Peregrino (1991)
Rendiconti del Seminario Matematico della Università di Padova
Moreno-Socías, Guillermo, Snellman, Jan (2002)
Homology, Homotopy and Applications
Alessandra Bernardi, Maria Virginia Catalisano (2006)
Collectanea Mathematica
We consider the k-osculating varietiesOk,d to the Veronese d?uple embeddings of P2. By studying the Hilbert function of certain zero-dimensional schemes Y ⊂ P2, we find the dimension of Osk,d, the (s?1)th secant varieties of Ok,d, for 3 ≤ s ≤ 6 and s = 9, and we determine whether those secant varieties are defective or not.
Pinter, Domotor, Ronyai, Lajos (2005)
Acta Universitatis Apulensis. Mathematics - Informatics
Rossi, Maria Evelina, Valla, Giuseppe (2001)
Beiträge zur Algebra und Geometrie
Maria Grazia Marinari (2001)
Bollettino dell'Unione Matematica Italiana
In this note we study some algebraic properties of Borel Ideals in the ring of polynomials over an effective field of characteristic zero by using a suitable partial order relation defined on the set of terms of each degree. In particular, in the three variable case, we characterize all the 0-dimensional Borel ideals corresponding to an admissible -vector and their minimal free resolutions.
Matthias Meulien (2004)
Annales de l’institut Fourier
On décrit l’algèbre des invariants de l’action naturelle du groupe sur les pinceaux de formes quintiques binaires.
Maria Francisca Blanco Blanco (2011)
Visual Mathematics
Ferruccio Orecchia, Isabella Ramella (1990)
Manuscripta mathematica
Ştefan, Alin (2007)
Analele Ştiinţifice ale Universităţii “Ovidius" Constanţa. Seria: Matematică
Amnon Neeman (1995)
Commentarii mathematici Helvetici
Tadahito Harima, Junzo Watanabe (2003)
Rendiconti del Seminario Matematico della Università di Padova
Jan Oddvar Kleppe (2006)
Annales de l’institut Fourier
This paper studies space curves of degree and arithmetic genus , with homogeneous ideal and Rao module , whose main results deal with curves which satisfy (e.g. of diameter, ). For such curves we find necessary and sufficient conditions for unobstructedness, and we compute the dimension of the Hilbert scheme, , at under the sufficient conditions. In the diameter one case, the necessary and sufficient conditions coincide, and the unobstructedness of turns out to be equivalent to the...
Ahmed Abbes, Thierry Bouche (1995)
Annales de l'institut Fourier
On donne une nouvelle démonstration directe du théorème de Hilbert-Samuel arithmétique et on déduit un critère numérique pour l’existence de sections d’un fibré en droite sur une variété arithmétique de norme sup inférieure à un.