A Unital Banach Algebra That Is Not a Calkin Algebra
The realisation problem asks which unital Banach algebras arise as the Calkin algebra $\mathcal{B}(X)/\mathcal{K}(X)$ of some Banach space. Recorded in Tarbard's thesis and studied by Horváth and Kania. The paper exhibits a unital Banach algebra that cannot be one.
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Scope and record
Occurred: Jul 19, 2026
Delta type: SOURCE CLAIM
Assumptions: VibeMathed verification: unreviewed. Publication: preprint. AI contribution: ai-co-developed. Imported under CC BY 4.0.
Canonical aliases: A Unital Banach Algebra That Is Not a Calkin Algebra · Non-Calkin algebra
Confidence: Not scored
Registry verification: unreviewed · preprint · resolved
Attribution
VibeMathed
registry · event recorded by
Antonio Acuaviva
human · human collaborator
Pablo Acuaviva
human · human collaborator
ChatGPT 5.5 Pro
model · ai model contributor · OpenAI
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This event attributed to Pablo Acuaviva
This event attributed to Antonio Acuaviva
This event attributed to ChatGPT 5.5 Pro