Projective Normality of Algebraic Curves and Its Application to Surfaces
نویسندگان
چکیده
Let L be a very ample line bundle on a smooth curve C of genus g with 3g+3 2 < degL ≤ 2g − 5. Then L is normally generated if degL > max{2g+2−4h(C,L), 2g− g−1 6 −2h(C,L)}. Let C be a triple covering of genus p curve C′ with C φ → C′ and D a divisor on C′ with 4p < degD < g−1 6 − 2p. Then KC(−φ ∗D) becomes a very ample line bundle which is normally generated. As an application, we characterize some smooth projective surfaces.
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تاریخ انتشار 2006