Dependence of Lyubeznik numbers of cones of projective schemes on projective embeddings
نویسندگان
چکیده
We construct complex projective schemes with Lyubeznik numbers of their cones depending on the choices embeddings. This answers a question G. in characteristic 0 case. It contrasts theorem W. Zhang positive case where Frobenius endomorphism is used. Reducibility essential our argument. B. Wang recently constructed examples irreducible (which are not normal) from reducible ones. So still open normal singular
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ژورنال
عنوان ژورنال: Selecta Mathematica-new Series
سال: 2021
ISSN: ['1022-1824', '1420-9020']
DOI: https://doi.org/10.1007/s00029-020-00612-3