Zobrazeno 1 - 10
of 85
pro vyhledávání: '"Ortega, Ángela"'
Autor:
Borówka, Paweł, Ortega, Angela
We investigate the geometry of smooth hyperelliptic curves that possess additional involutions, especially from the point of view of the Prym theory. Our main result is the injectivity of the Prym map for hyperelliptic $\mathbb{Z}_2^2$-coverings over
Externí odkaz:
http://arxiv.org/abs/2302.13041
Publikováno v:
Pure and Applied Mathematics Quarterly 18 (2022), 1211-1263 (Clemens volume)
In previous work we showed that the Hurwitz space of W(E_6)-covers of the projective line branched over 24 points dominates via the Prym-Tyurin map the moduli space A_6 of principally polarized abelian 6-folds. Here we determine the 25 Hodge classes
Externí odkaz:
http://arxiv.org/abs/2107.09691
Autor:
Naranjo, Juan Carlos, Ortega, Ángela
We prove that the ramified Prym map $\mathcal P_{g, r}$ which sends a covering $\pi:D\longrightarrow C$ ramified in $r$ points to the Prym variety $P(\pi):=\text{Ker}(\text{Nm}_{\pi})$ is an embedding for all $r\ge 6$ and for all $g(C)>0$. Moreover,
Externí odkaz:
http://arxiv.org/abs/2005.11108
Autor:
Borówka, Paweł, Ortega, Angela
We investigate the geometry of \'etale $4:1$ coverings of smooth complex genus 2 curves with the monodromy group isomorphic to the Klein four-group. There are two cases, isotropic and non-isotropic depending on the values of the Weil pairing restrict
Externí odkaz:
http://arxiv.org/abs/1904.05962
Autor:
Lange, Herbert, Ortega, Angela
To every double cover ramified in two points of a general trigonal curve of genus g, one can associate an \'etale double cover of a tetragonal curve of genus g+1. We show that the corresponding Prym varieties are canonically isomorphic as principally
Externí odkaz:
http://arxiv.org/abs/1902.00251
Let $(E,V)$ be a general generated coherent system of type $(n,d,n+m)$ on a general non-singular irreducible complex projective curve. A conjecture of D. C. Butler relates the semistability of $E$ to the semistability of the kernel of the evaluation
Externí odkaz:
http://arxiv.org/abs/1711.04815
In this paper we consider the Prym map for double coverings of curves of genus $g$ ramified at $r>0$ points. That is, the map associating to a double ramified covering its Prym variety. The generic Torelli theorem states that the Prym map is generica
Externí odkaz:
http://arxiv.org/abs/1708.06512
Autor:
Borówka, Paweł, Ortega, Angela
Publikováno v:
Math Z. vol. 292, Issue 1-2 (2019), 193-209
We investigate the number and the geometry of smooth hyperelliptic curves on a general complex abelian surface. We show that the only possibilities of genera of such curves are $2,3,4$ and $5$. We focus on the genus 5 case. We prove that up to transl
Externí odkaz:
http://arxiv.org/abs/1708.01270
Autor:
Lange, Herbert, Ortega, Angela
We study the Prym varieties arising from \'etale cyclic coverings of degree 7 over a curve of genus 2. These Prym varieties are products of Jacobians JY x JY of genus 3 curves Y with polarization type D=(1,1,1,1,1,7). We describe the fibers of the Pr
Externí odkaz:
http://arxiv.org/abs/1604.01700
Autor:
Lange, Herbert, Ortega, Angela
It is well known that the Prym variety of an \'etale cyclic covering of a hyperelliptic curve is isogenous to the product of two Jacobians. Moreover, if the degree of the covering is odd or congruent to 2 mod 4, then the canonical isogeny is an isomo
Externí odkaz:
http://arxiv.org/abs/1601.04082