Zobrazeno 1 - 10
of 170
pro vyhledávání: '"Hartshorne, Robin"'
Autor:
Hartshorne, Robin, Polini, Claudia
We develop the theory of coregular sequences and codepth for modules that need not be finitely generated or artinian over a Noetherian ring. We use this theory to give a new version of a theorem of Hellus characterizing set-theoretic complete interse
Externí odkaz:
http://arxiv.org/abs/1907.05472
Autor:
Polini, Claudia, Hartshorne, Robin
For a projective variety V in P^n over a field of characteristic zero, with homogeneous ideal I in A = k[x0,x1,...,xn], we consider the local cohomology modules H^i_I(A). These have a structure of holonomic D-module over A, and we investigate their f
Externí odkaz:
http://arxiv.org/abs/1606.01278
Autor:
Hartshorne, Robin, Polini, Claudia
Publikováno v:
In Journal of Algebra 1 April 2021 571:232-257
Autor:
Hartshorne, Robin, Polini, Claudia
We compute divisors class groups of singular surfaces. Most notably we produce an exact sequence that relates the Cartier divisors and almost Cartier divisors of a surface to the those of its normalization. This generalizes Hartshorne's theorem for t
Externí odkaz:
http://arxiv.org/abs/1301.3222
Using the possibility of computationally determining points on a finite cover of a unirational variety over a finite field, we determine all possibilities for direct Gorenstein linkages between general sets of points in P^3 over an algebraically clos
Externí odkaz:
http://arxiv.org/abs/1212.1841
Let $H_{d,g}$ denote the Hilbert scheme of locally Cohen-Macaulay curves of degree $d$ and genus $g$ in projective three space. We show that, given a smooth irreducible curve $C$ of degree $d$ and genus $g$, there is a rational curve $\{[C_t]: t \in
Externí odkaz:
http://arxiv.org/abs/1207.4588
Autor:
Casanellas, Marta, Hartshorne, Robin
The existence of stable ACM vector bundles of high rank on algebraic varieties is a challenging problem. In this paper, we study stable Ulrich bundles (that is, stable ACM bundles whose corresponding module has the maximum number of generators) on no
Externí odkaz:
http://arxiv.org/abs/1102.0878
Autor:
Hartshorne, Robin, Schlesinger, Enrico
Let C be an ACM (projectively normal) nondegenerate smooth curve in projective 3-space, and suppose C is general in its Hilbert scheme - this is irreducible once the postulation is fixed. Answering a question posed by Peskine, we show the gonality of
Externí odkaz:
http://arxiv.org/abs/0812.1634
Autor:
Casanellas, Marta, Hartshorne, Robin
In this paper we prove that, for every $r \geq 2$, the moduli space $M^s_X(r;c_1,c_2)$ of rank $r$ stable vector bundles with Chern classes $c_1=rH$ and $c_2=(3r^2-r)/2$ on a nonsingular cubic surface $X \subset \mathbb{P}^3$ contains a nonempty smoo
Externí odkaz:
http://arxiv.org/abs/0801.3600