Canonical Projectivization of Algebraic Varieties in Characteristic Zero
Abstract
We construct a canonical projectivization of every smooth proper algebraic variety X in characteristic zero. Once a principalization procedure is fixed, the construction gives a finite sequence of blowups in smooth centers with smooth projective endpoint, natural under semilinear isomorphisms and preserving the quasi-projective core, the intersection of all maximal quasi-projective open subsets. At each stage we select finitely many ideals near the generic points of the image in X of the boundary of a maximal quasi-projective open. Principalizing their product strictly lowers the dimension of that image. The selection is defined intrinsically, without a polarization or a chosen projective modification; a Hilbert scheme argument proves its finiteness. Naturality embeds the automorphism group in that of a smooth projective variety of the same dimension. We then extend the construction to smooth proper integral algebraic spaces, obtaining canonical projectivizations of all compact connected Moishezon manifolds.
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BibTeX
@misc{bakhtary2026canonical,
title = {{Canonical Projectivization of Algebraic Varieties in Characteristic Zero}},
author = {Parsa Bakhtary},
howpublished = {arXiv},
year = {2026},
month = nov,
doi = {10.48550/arxiv.2611.04314},
eprint = {2611.04314},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2611.04314},
note = {CC BY 4.0},
}
RIS
TY - UNPB
TI - Canonical Projectivization of Algebraic Varieties in Characteristic Zero
AU - Parsa Bakhtary
PY - 2026
DA - 2026/11/03
PB - arXiv
DO - 10.48550/arxiv.2611.04314
UR - https://arxiv.org/abs/2611.04314
AB - We construct a canonical projectivization of every smooth proper algebraic variety X in characteristic zero. Once a principalization procedure is fixed, the construction gives a finite sequence of blowups in smooth centers with smooth projective endpoint, natural under semilinear isomorphisms and preserving the quasi-projective core, the intersection of all maximal quasi-projective open subsets. At each stage we select finitely many ideals near the generic points of the image in X of the boundary of a maximal quasi-projective open. Principalizing their product strictly lowers the dimension of that image. The selection is defined intrinsically, without a polarization or a chosen projective modification; a Hilbert scheme argument proves its finiteness. Naturality embeds the automorphism group in that of a smooth projective variety of the same dimension. We then extend the construction to smooth proper integral algebraic spaces, obtaining canonical projectivizations of all compact connected Moishezon manifolds.
ER -