Source authenticated

Katsumasa–Roff–Yoshinaga conjecture on Hausdorff continuity of magnitude

Yes, with a quantitative bound: magnitude is Hausdorff-continuous at every nonempty finite subset of a finite-dimensional positive definite normed space, with a local Lipschitz-type estimate in the Hausdorff distance whose constants depend on the number of points, the dimension and the least eigenvalue of the similarity matrix, and with compact approximants allowed. The paper also obtains convergence of aggregated weights and a continuity criterion in L_1 by local order oscillation, and, in the other direction, a compact convex subset of L_1[0,1] whose finite subsets approach a singleton with magnitudes tending to 3/2, which refutes an implication stated in Kalisnik and Lesnik's preprint from the one-point property to singleton continuity.

Exact FrontierDelta

Prior state unknown→proved

Scope and record

Occurred: Sep 20, 2026

Delta type: SOURCE CLAIM

Assumptions: VibeMathed verification: unreviewed. Publication: preprint. AI contribution: ai-co-developed. VibeMathed editorial classifications, scores, notes, relations, and dataset structure are CC BY 4.0. Source statements and linked content retain their own rights.

Canonical aliases: Katsumasa–Roff–Yoshinaga conjecture on Hausdorff continuity of magnitude · Magnitude continuity at finite sets

Confidence: Not scored

Registry verification: unreviewed · preprint · candidate

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Attribution

VibeMathed
registry · event recorded by

GPT-6 Astra Pro
model · ai model contributor · OpenAI

Claude Fable 5.1
model · ai model contributor · Anthropic

Mingchang Liu
human · human collaborator

Lineage and corrections

This event attributed to Claude Fable 5.1

This event attributed to GPT-6 Astra Pro

Yes, with a quantitative bound: magnitude is Hausdorff-continuous at every nonempty finite subset of a finite-dimensional positive definite normed space, with a local Lipschitz-type estimate in the Hausdorff distance whose constants depend on the number of points, the dimension and the least eigenvalue of the similarity matrix, and with compact approximants allowed. The paper also obtains convergence of aggregated weights and a continuity criterion in L_1 by local order oscillation, and, in the other direction, a compact convex subset of L_1[0,1] whose finite subsets approach a singleton with magnitudes tending to 3/2, which refutes an implication stated in Kalisnik and Lesnik's preprint from the one-point property to singleton continuity. parent of this event

Katsumasa, Roff and Yoshinaga (2025), Conjecture 1.3 evidence for this event

This event attributed to Mingchang Liu

Katsumasa–Roff–Yoshinaga conjecture on Hausdorff continuity of magnitude evidence for this event

Katsumasa–Roff–Yoshinaga conjecture on Hausdorff continuity of magnitude parent of this event

Kalisnik and Lesnik (2025), the skew-subset partial result evidence for this event

VibeMathed record: Katsumasa–Roff–Yoshinaga conjecture on Hausdorff continuity of magnitude evidence for this event

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