Projective varieties have countably many real forms

نویسندگان

چکیده

In this note, we check that a complex projective algebraic variety has (at most) countably many real forms. We more generally prove it when the field of reals is replaced with only finite extensions up to isomorphism. The verification consists in gathering known results about automorphism groups and Galois cohomology. This contrasts recent discovery by A. Bot an affine uncountably

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ژورنال

عنوان ژورنال: Comptes Rendus Mathematique

سال: 2023

ISSN: ['1631-073X', '1778-3569']

DOI: https://doi.org/10.5802/crmath.441