Abstract
It is known that if $X$ is an $n$--dimensional normal variety, and $D$ a nef and big Cartier divisor on it such that the associated map $\varphi_D$ is generically finite then $D^n\geq 2(h^0(X,\Oc_X(D))-n)$. We study the case in which the equality holds for $n=3$ and $D=K_X$ is the canonical divisor. \par We also produce a bound for the admissible degree of the canonical map of a threefold, when it is supposed to be generically finite.
Citation
Paola Supino. "On threefolds with ${\mathbf K^3=2p_g-6}$." Kodai Math. J. 27 (1) 7 - 29, March 2004. https://doi.org/10.2996/kmj/1085143786
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