dorsal/arxiv
View Schema$A_3$-formality for Demushkin groups at odd primes
| Authors | Ambrus Pál, Gereon Quick |
|---|---|
| Categories | |
| ArXiv ID | 2601.07551vv2 |
| URL | https://arxiv.org/abs/2601.07551 |
| License | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ |
Abstract
We study a weak form of formality for differential graded algebras, called $A_3$-formality, for the cohomology of pro-p Demushkin groups at odd primes p. We show that the differential graded $\mathbb{F}_p$-algebras of continuous cochains of Demushkin groups with q-invariant not equal 3 are $A_3$-formal, whereas Demushkin groups with q-invariant 3 are not $A_3$-formal. We prove these results by an explicit computation of the Benson-Krause-Schwede canonical class in Hochschild cohomology.
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"abstract": "We study a weak form of formality for differential graded algebras, called $A_3$-formality, for the cohomology of pro-p Demushkin groups at odd primes p. We show that the differential graded $\\mathbb{F}_p$-algebras of continuous cochains of Demushkin groups with q-invariant not equal 3 are $A_3$-formal, whereas Demushkin groups with q-invariant 3 are not $A_3$-formal. We prove these results by an explicit computation of the Benson-Krause-Schwede canonical class in Hochschild cohomology.",
"arxiv_id": "2601.07551",
"authors": [
"Ambrus P\u00e1l",
"Gereon Quick"
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"license": "http://arxiv.org/licenses/nonexclusive-distrib/1.0/",
"title": "$A_3$-formality for Demushkin groups at odd primes",
"url": "https://arxiv.org/abs/2601.07551",
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