On Bousfield’s conjectures for the unstable Adams spectral sequence for $SO$ and $U$

The unstable Adams spectral sequence is a spectral sequence that starts from algebraic information about the mod $2 $ cohomology $H ^{ * } \left(X \right) $ of a space $X $ as an unstable algebra over the Steenrod algebra $\mathcal{A}$, and converges, in good cases, to the $2 $-localized homotopy gr...

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Main Author: Nguyễn, Thế Cường
Format: Article
Language:English
Published: Académie des sciences 2023-12-01
Series:Comptes Rendus. Mathématique
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Online Access:https://comptes-rendus.academie-sciences.fr/mathematique/articles/10.5802/crmath.531/
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author Nguyễn, Thế Cường
author_facet Nguyễn, Thế Cường
author_sort Nguyễn, Thế Cường
collection DOAJ
description The unstable Adams spectral sequence is a spectral sequence that starts from algebraic information about the mod $2 $ cohomology $H ^{ * } \left(X \right) $ of a space $X $ as an unstable algebra over the Steenrod algebra $\mathcal{A}$, and converges, in good cases, to the $2 $-localized homotopy groups of $X $. Bousfield and Don Davis looked at the case when $X $ was either of the infinite matrix groups $SO$ or $U$. Bousfield and Davis created algebraic spectral sequences and conjectured that they agreed with the unstable Adams spectral sequences for $SO $ and $U $. To this end the following algebraic decomposition must hold \[ \mathrm{Ext} _{ \mathcal{U} } ^{ s } \left(\tilde{ H } ^{ * } \left(\mathbb{R} P ^{ \infty }, \Sigma ^{ t } \mathbb{Z} /2 \right) \right) \cong \bigoplus _{ n } \mathrm{Ext}_{ \mathcal{U} } ^{ s } \left(M _{ n } / M _{ n - 1 },\Sigma ^{ t } \mathbb{Z} /2 \right) \] where $M _{ 1 } \subset M _{ 2 } \subset \cdots $ is the well known dyadic filtration of the $\mathcal{A}$-module $\tilde{ H } ^{ * } \left(\mathbb{R} P ^{ \infty }, \mathbb{Z} /2 \right) \cong \mathbb{F} _{ 2 } \left[u \right] $ given by the dyadic expansion of the powers of $u $. This paper aims at showing that this decomposition holds for numerous values of $s $ and $t $.
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spelling doaj-art-1b069446a0f34a1cba6e42ac27efe0b62025-02-07T11:12:14ZengAcadémie des sciencesComptes Rendus. Mathématique1778-35692023-12-01361G111789180410.5802/crmath.53110.5802/crmath.531On Bousfield’s conjectures for the unstable Adams spectral sequence for $SO$ and $U$Nguyễn, Thế Cường0Department of Mathematics, Informatics and Mechanics, VNU University of Science, Vietnam National University, HanoiThe unstable Adams spectral sequence is a spectral sequence that starts from algebraic information about the mod $2 $ cohomology $H ^{ * } \left(X \right) $ of a space $X $ as an unstable algebra over the Steenrod algebra $\mathcal{A}$, and converges, in good cases, to the $2 $-localized homotopy groups of $X $. Bousfield and Don Davis looked at the case when $X $ was either of the infinite matrix groups $SO$ or $U$. Bousfield and Davis created algebraic spectral sequences and conjectured that they agreed with the unstable Adams spectral sequences for $SO $ and $U $. To this end the following algebraic decomposition must hold \[ \mathrm{Ext} _{ \mathcal{U} } ^{ s } \left(\tilde{ H } ^{ * } \left(\mathbb{R} P ^{ \infty }, \Sigma ^{ t } \mathbb{Z} /2 \right) \right) \cong \bigoplus _{ n } \mathrm{Ext}_{ \mathcal{U} } ^{ s } \left(M _{ n } / M _{ n - 1 },\Sigma ^{ t } \mathbb{Z} /2 \right) \] where $M _{ 1 } \subset M _{ 2 } \subset \cdots $ is the well known dyadic filtration of the $\mathcal{A}$-module $\tilde{ H } ^{ * } \left(\mathbb{R} P ^{ \infty }, \mathbb{Z} /2 \right) \cong \mathbb{F} _{ 2 } \left[u \right] $ given by the dyadic expansion of the powers of $u $. This paper aims at showing that this decomposition holds for numerous values of $s $ and $t $.https://comptes-rendus.academie-sciences.fr/mathematique/articles/10.5802/crmath.531/Injective resolutionProjective resolutionUnstable Adams spectral sequenceUnstable modules
spellingShingle Nguyễn, Thế Cường
On Bousfield’s conjectures for the unstable Adams spectral sequence for $SO$ and $U$
Comptes Rendus. Mathématique
Injective resolution
Projective resolution
Unstable Adams spectral sequence
Unstable modules
title On Bousfield’s conjectures for the unstable Adams spectral sequence for $SO$ and $U$
title_full On Bousfield’s conjectures for the unstable Adams spectral sequence for $SO$ and $U$
title_fullStr On Bousfield’s conjectures for the unstable Adams spectral sequence for $SO$ and $U$
title_full_unstemmed On Bousfield’s conjectures for the unstable Adams spectral sequence for $SO$ and $U$
title_short On Bousfield’s conjectures for the unstable Adams spectral sequence for $SO$ and $U$
title_sort on bousfield s conjectures for the unstable adams spectral sequence for so and u
topic Injective resolution
Projective resolution
Unstable Adams spectral sequence
Unstable modules
url https://comptes-rendus.academie-sciences.fr/mathematique/articles/10.5802/crmath.531/
work_keys_str_mv AT nguyenthecuong onbousfieldsconjecturesfortheunstableadamsspectralsequenceforsoandu