Norms in motivic homotopy theory

If f:S ->S is a finite locally free morphism of schemes, we construct a symmetric monoidal "norm" functor f :H (S )->H (S), where H (S) is the pointed unstable motivic homotopy category over S. If f is finite étale, we show that it stabilizes to a functor f :SH(S )->SH(S), where S...

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Détails bibliographiques
Auteurs principaux : Bachmann Tom (Auteur), Hoyois Marc (Auteur)
Format : Livre
Langue : anglais
Titre complet : Norms in motivic homotopy theory / Tom Bachmann & Marc Hoyois
Publié : Paris : Société mathématique de France , C 2021
Description matérielle : 1 vol. (ix-207 p.)
Collection : Astérisque ; 425
Sujets :
Documents associés : Fait partie de l'ensemble: Astérisque
Description
Résumé : If f:S ->S is a finite locally free morphism of schemes, we construct a symmetric monoidal "norm" functor f :H (S )->H (S), where H (S) is the pointed unstable motivic homotopy category over S. If f is finite étale, we show that it stabilizes to a functor f :SH(S )->SH(S), where SH(S) is the P1-stable motivic homotopy category over S. Using these norm functors, we define the notion of a normed motivic spectrum, which is an enhancement of a motivic E-ring spectrum. The main content of this text is a detailed study of the norm functors and of normed motivic spectra, and the construction of examples. In particular: we investigate the interaction of norms with Grothendieck's Galois theory, with Betti realization, and with Voevodsky's slice filtration; we prove that the norm functors categorify Rost's multiplicative transfers on Grothendieck-Witt rings; and we construct normed spectrum structures on the motivic cohomology spectrum HZ, the homotopy K-theory spectrum KGL, and the algebraic cobordism spectrum MGL. The normed spectrum structure on HZ is a common refinement of Fulton and MacPherson's mutliplicative transfers on Chow groups and of Voevodsky's power operations in motivic cohomology.
Notes : Résumés en anglais et en français
Historique des publications : N° de : "Astérisque", ISSN 0303-1179, (2021) n°425
Bibliographie : Bibliographie p. [199]-207
ISBN : 978-2-85629-939-5