Article de recherche - Géométrie algébrique, Théorie des nombres
Some remarks on the companions conjecture for normal varieties
Comptes Rendus. Mathématique, Tome 362 (2024) no. G1, pp. 63-69

Drinfeld in 2010 proved the companions conjecture for smooth varieties over a finite field, generalizing L. Lafforgue’s result for smooth curves. We study the obstruction to prove the conjecture for arbitrary normal varieties. To do this, we introduce a new property of morphisms. We verify this property in some cases, showing thereby the companions conjecture for some singular normal varieties.

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DOI : 10.5802/crmath.527
Classification : 14G15
Keywords: $\ell $-adic representation, independence of $\ell $, étale fundamental group

D’Addezio, Marco  1

1 Institut de Mathématiques de Jussieu-Paris Rive Gauche, SU - 4 place Jussieu, Case 247, 75005 Paris
Licence : CC-BY 4.0
Droits d'auteur : Les auteurs conservent leurs droits
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     title = {Some remarks on the companions conjecture for normal varieties},
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     pages = {63--69},
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D’Addezio, Marco. Some remarks on the companions conjecture for normal varieties. Comptes Rendus. Mathématique, Tome 362 (2024) no. G1, pp. 63-69. doi: 10.5802/crmath.527

[1] D’Addezio, Marco The monodromy groups of lisse sheaves and overconvergent F-isocrystals, Sel. Math., New Ser., Volume 26 (2020) no. 3, 45, 41 pages | MR | Zbl

[2] Deligne, Pierre La Conjecture de Weil. II, Publ. Math., Inst. Hautes Étud. Sci., Volume 52 (1980), pp. 137-252 | DOI | Numdam | Zbl

[3] Deligne, Pierre Finitude de l’extension de engendrée par des traces de Frobenius, en caractéristique finie, Mosc. Math. J., Volume 12 (2012) no. 3, pp. 497-514 | Zbl | DOI

[4] Drinfeld, Vladimir On a conjecture of Deligne, Mosc. Math. J., Volume 12 (2012), pp. 515-542 | DOI | MR | Zbl

[5] Grothendieck, Alexander; Raynaud, Michèle Revêtements étales et groupe fondamental (SGA 1), Lecture Notes in Mathematics, 224, Springer, 1971 | DOI

[6] Lafforgue, Laurent Chtoucas de Drinfeld et correspondance de Langlands, Invent. Math., Volume 147 (2002) no. 1, pp. 1-241 | DOI | MR | Zbl

[7] Larsen, Michael; Pink, Richard Abelian varieties, -adic representations, and -independence, Math. Ann., Volume 302 (1995) no. 3, pp. 561-580 | DOI | MR | Zbl

[8] Lasell, Brendon; Ramachandran, Mohan Observations on harmonic maps and singular varieties, Ann. Sci. Éc. Norm. Supér., Volume 29 (1996) no. 2, pp. 135-148 | DOI | MR | Numdam | Zbl

[9] Oort, Frans A Stratification of a Moduli Space of Abelian Varieties, Moduli of Abelian varieties (Progress in Mathematics), Volume 195, Birkhäuser, 2001, pp. 345-416 | DOI | MR | Zbl

[10] The Stacks Project Authors Stacks Project (http://stacks.math.columbia.edu)

[11] Stix, Jakob A general Seifert-Van Kampen theorem for algebraic fundamental groups, Publ. Res. Inst. Math. Sci., Volume 42 (2006) no. 3, pp. 763-786 | DOI | MR | Zbl

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