Real forms of some Gizatullin surfaces and Koras-Russell threefolds

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Jérémy Blanc
Universität Basel. Departement Mathematik und Informatik
Anna Bot
Universität Basel. Departement Mathematik und Informatik
https://orcid.org/0000-0001-7803-1518
Pierre-Marie Poloni
Universität Basel. Departement Mathematik und Informatik

We describe the real forms of Gizatullin surfaces of the form xy = p(z) and of Koras–Russell threefolds of the first kind. The former admit zero, two, three, four, or six isomorphism classes of real forms, depending on the degree and the symmetries of the polynomial p. The latter, which are threefolds given by an equation of the form x dy + z k + x + t l = 0, all admit exactly one real form up to isomorphism.

Paraules clau
real forms, Gizatullin surfaces, Danielewski surfaces, Koras–Russell threefolds, group cohomology

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Blanc, Jérémy et al. «Real forms of some Gizatullin surfaces and Koras-Russell threefolds». Publicacions Matemàtiques, 2023, vol.VOL 67, núm. 2, p. 851-90, http://raco.cat/index.php/PublicacionsMatematiques/article/view/418522.
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