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Research notes on every problem, and a library of the papers behind them. Built from the open erdos repository.

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Subhajit Ghosh and Koushik Ramachandran, A note on the Erdős minimal area problem, Proc. Amer. Math. Soc., published online 28 August 2026, DOI 10.1090/proc/17897 (arXiv:2604.03036, v1 of 3 April 2026, v3 of 27 August 2026), answer the first question negatively and settle the second for compact sets of capacity above 11. With An(K)A_n(K) the minimal area of {z:∣p(z)∣<1}\{z:|p(z)|<1\} over monic pp of degree nn with all zeros in KK and ϑ(K)=inf⁡nAn(K)\vartheta(K)=\inf_nA_n(K), Theorem 3.1 states that a compact KK with cap⁡(K)=t>1\operatorname{cap}(K)=t>1 has lim sup⁡n1nlog⁡An(K)≤−2log⁡t\limsup_n\frac1n\log A_n(K)\le-2\log t, so ϑ(K)=0\vartheta(K)=0, the Fekete polynomials of KK giving the upper bound; Theorem 3.3 gives the matching lower bound, so that 1nlog⁡An(K)→−2log⁡t\frac1n\log A_n(K)\to-2\log t for every such KK with no regularity assumption, and the Fekete polynomials are asymptotic minimizers. Example 2.1 answers the first question negatively at every capacity t∈(0,1)t\in(0,1): two short symmetric intervals [j,j+ε]∪[−j−ε,−j][j,j+\varepsilon]\cup[-j-\varepsilon,-j] of capacity tt have ϑ\vartheta below any prescribed bound once jj is large, while the disc of radius tt has ϑ≥πr(t)2\vartheta\ge\pi r(t)^2 by the theorem of Erdős and Netanyahu. A final section proves An([−2,2])≤c1/nA_n([-2,2])\le c_1/n (Theorem 4.1; Remark 4.2 announces a matching lower bound without proof) and sets it against the lower bound An(D‾)≥c/log⁡nA_n(\overline{\mathbb D})\ge c/\log n of Krishnapur, Lundberg and Ramachandran, so the decay rate at capacity 11 is not universal. The introduction states that the general compact case of capacity 11 remains open and cites the smooth case of Krishnapur, Lundberg and Ramachandran. The statements above are those of arXiv v3; the proofs are not checked here.

Covers. The first question, answered negatively at every capacity in (0,1)(0,1) by Example 2.1, beside Aletheia's capacity-zero pair; this is the part the page's value records. It also settles the second question for compact sets of capacity above 11, μ(K)=0\mu(K)=0 with exponential decay of the degree-nn minimal area at the sharp rate, a partial yes to that question which the page's value does not record. Its Theorem 4.1 also gives μ([−2,2])=0\mu([-2,2])=0, a capacity-one case that Erdős, Herzog and Piranian had noted; it says nothing about other compact sets of capacity exactly 11 beyond the cited smooth case of Krishnapur, Lundberg and Ramachandran, nor about unbounded closed sets.

Refereed. Proceedings of the American Mathematical Society, DOI 10.1090/proc/17897, published online 28 August 2026 according to the Crossref record (checked 2026-10-07; no volume or pages assigned); the arXiv comments of v3 state the acceptance. The site's commentary, last edited 1 February 2026, does not name the paper; a thread comment of 6 April 2026 pointed to the preprint, and later claimants on the second question cite the theorem for the case of capacity above 11.