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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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Manjunath Krishnapur, Erik Lundberg and Koushik Ramachandran, On the area of polynomial lemniscates, arXiv:2503.18270 (24 March 2025), prove a regular case of the second question. For a compact KK let κn(K,1)\kappa_n(K,1) be the minimal area of {z:∣p(z)∣<1}\{z:|p(z)|<1\} over monic pp of degree nn with all zeros in KK. Theorem 6 states that if KK is the closure of a bounded open set with C2C^2-smooth boundary and has capacity 11, then inf⁡nκn(K,1)=0\inf_n\kappa_n(K,1)=0, which is μ(K)=0\mu(K)=0 in the problem's notation; Theorem 7 adds that for any compact KK of capacity 11, zeros of polynomials whose sublevel areas in KK tend to zero equidistribute to the equilibrium measure of KK. For the closed unit disc, the case Erdős, Herzog and Piranian had settled qualitatively, the paper proves c/log⁡n≤κn(D‾,1)≤C/log⁡log⁡nc/\log n\le\kappa_n(\overline{\mathbb D},1)\le C/\log\log n, improving Pommerenke's lower bound and Wagner's upper bound. Its introduction records that the case of capacity above 11 had been treated under a regularity condition in the authors' earlier paper, Inradius of random lemniscates, J. Approx. Theory 299 (2024), Paper No. 106018, whose Corollary 1.6 gives μ(K)=0\mu(K)=0 for compact KK of capacity above 11 under a Frostman-type bound on the equilibrium measure (recorded on its page), and that the general unit-capacity case loses quantitative control. The paper's library card records it; the statements above are those of the arXiv version, and the proofs are not checked here.

Covers. The second question for one class of sets: a compact KK of capacity 11 that is the closure of a bounded open set with C2C^2 boundary has μ(K)=0\mu(K)=0. The claim says nothing about other compact sets of capacity 11, about unbounded closed sets, or about the first question; the case of capacity above 11 is recorded on [[problems/analysis/E1040/claims/2026_04_03_ghosh_ramachandran|the page of Ghosh and Ramachandran]], and the general case on the four later pages of the folder.

Standing. The arXiv record lists no journal reference (checked 2026-10-07), the paper is not named on the site's page or thread, and no reviewer is named, so the claim stays claimed.