𝔸1–connected components of ruled surfaces
Geometry & topology, Tome 26 (2022) no. 1, pp. 321-376.

Voir la notice de l'article provenant de la source Mathematical Sciences Publishers

A conjecture of Morel asserts that the sheaf of 𝔸1–connected components of a space is 𝔸1–invariant. Using purely algebrogeometric methods, we determine the sheaf of 𝔸1–connected components of a smooth projective surface, which is birationally ruled over a curve of genus > 0. As a consequence, we show that Morel’s conjecture holds for all smooth projective surfaces over an algebraically closed field of characteristic 0.

Keywords: $\mathbb A^1$–connected components, ghost homotopies, ruled surfaces

Balwe, Chetan 1 ; Sawant, Anand 2

1 Department of Mathematical Sciences, Indian Institute of Science Education and Research, Mohali, India
2 School of Mathematics, Tata Institute of Fundamental Research, Mumbai, India
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Balwe, Chetan; Sawant, Anand. 𝔸1–connected components of ruled surfaces. Geometry & topology, Tome 26 (2022) no. 1, pp. 321-376. http://geodesic.mathdoc.fr/item/GT_2022_26_1_a7/

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