Abstract.
The bad locus and the rude locus of an ample and base point free linear system on a smooth complex projective variety are introduced and studied. Polarized surfaces of small degree, or whose degree is the square of a prime, with nonempty bad loci are completely classified. Several explicit examples are offered to describe the variety of behaviors of the two loci.
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Mathematics Subject Classification (2000): 14C20, 14J25
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Besana, G., Di Rocco, S. & Lanteri, A. Peculiar loci of ample and spanned line bundles. manuscripta math. 112, 197–219 (2003). https://doi.org/10.1007/s00229-003-0395-z
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DOI: https://doi.org/10.1007/s00229-003-0395-z