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On rank 2 semistable vector bundles over an irreducible nodal curve of genus 2

Sonia Brivio (1998)

Bollettino dell'Unione Matematica Italiana

Sia C una curva irriducibile nodale di genere aritmetico p a = 2 . In queste note vogliamo mostrare come il sistema lineare delle quadriche, contenenti un opportuno modello proiettivo della curva, permette di descrivere i fibrati vettoriali semistabili, di rango 2 , su C .

On ranks of Jacobian varieties in prime degree extensions

Dave Mendes da Costa (2013)

Acta Arithmetica

T. Dokchitser [Acta Arith. 126 (2007)] showed that given an elliptic curve E defined over a number field K then there are infinitely many degree 3 extensions L/K for which the rank of E(L) is larger than E(K). In the present paper we show that the same is true if we replace 3 by any prime number. This result follows from a more general result establishing a similar property for the Jacobian varieties associated with curves defined by an equation of the shape f(y) = g(x) where f and g are polynomials...

On the geometry of moduli of curves and line bundles

Claudio Fontanari (2005)

Atti della Accademia Nazionale dei Lincei. Classe di Scienze Fisiche, Matematiche e Naturali. Rendiconti Lincei. Matematica e Applicazioni

Here we focus on the geometry of P ¯ d , g , the compactification of the universal Picard variety constructed by L. Caporaso. In particular, we show that the moduli space of spin curves constructed by M. Cornalba naturally injects into P ¯ d , g and we give generators and relations of the rational Picard group of P ¯ d , g , extending previous work by A. Kouvidakis.

On the Hodge cycles of Prym varieties

Indranil Biswas (2004)

Annali della Scuola Normale Superiore di Pisa - Classe di Scienze

We show that the Néron–Severi group of the Prym variety for a degree three unramified Galois covering of a hyperelliptic Riemann surface has a distinguished subgroup of rank three. For the general hyperelliptic curve, the algebra of Hodge cycles on the Prym variety is generated by this group of rank three.

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