On the stability of the universal quotient bundle restricted to congruences of low degree of 𝔾(1,3)
Annali della Scuola Normale Superiore di Pisa - Classe di Scienze, Serie 5, Volume 9 (2010) no. 3, p. 503-522

We study the semistability of Q| S , the universal quotient bundle on 𝔾(1,3) restricted to any smooth surface S (called congruence). Specifically, we deduce geometric conditions for a congruence S, depending on the slope of a saturated linear subsheaf of Q| S . Moreover, we check that the Dolgachev-Reider Conjecture (i.e. the semistability of Q| S for nondegenerate congruences S) is true for all the congruences of degree less than or equal to 10. Also, when the degree of a congruence S is less than or equal to 9, we compute the highest slope reached by the linear subsheaves of Q| S .

Classification:  14J60,  14M07,  14M15
@article{ASNSP_2010_5_9_3_503_0,
     author = {Arrondo, Enrique and Cobo, Sof\'\i a},
     title = {On the stability of the universal quotient bundle restricted to congruences of low degree of $\mathbb{G}{\bf (1,3)}$},
     journal = {Annali della Scuola Normale Superiore di Pisa - Classe di Scienze},
     publisher = {Scuola Normale Superiore, Pisa},
     volume = {Ser. 5, 9},
     number = {3},
     year = {2010},
     pages = {503-522},
     zbl = {1202.14038},
     mrnumber = {2722653},
     language = {en},
     url = {http://www.numdam.org/item/ASNSP_2010_5_9_3_503_0}
}
Arrondo, Enrique; Cobo, Sofía. On the stability of the universal quotient bundle restricted to congruences of low degree of $\mathbb{G}{\bf (1,3)}$. Annali della Scuola Normale Superiore di Pisa - Classe di Scienze, Serie 5, Volume 9 (2010) no. 3, pp. 503-522. http://www.numdam.org/item/ASNSP_2010_5_9_3_503_0/

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