Research notes on every problem, and a library of the papers behind them. Built from the open erdos repository.
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Claim. There are absolute constants such that for every ,
the infimum over monic of degree with all zeros in the closed unit disk. This is the main theorem of Krishnapur, Lundberg and Ramachandran, On the area of polynomial lemniscates, arXiv:2503.18270 (2025-03-24, 44 pages), digested on the card [[../library/polynomials/krishnapur_2025_area_polynomial_lemniscates/_index|Krishnapur, Lundberg and Ramachandran 2025]]. The lower bound answers the stronger, parenthetical form of Problem 116, an area of at least , with exponent , and so also the form that Pommerenke 1961 settled with exponent ; the upper bound sharpens Wagner's construction [Wa88], whose area was , and leaves a gap between and , which Pendyala's 2026 preprint (arXiv:2606.17097) claims to close at order . The paper derives the bounds from a finer theorem relating the closed-disk constraint to zeros on the unit circle, with potential theory, equilibrium measures and a probabilistic construction; it also gives the sharp order for the sublevel sets at every level above and an inradius bound of order , which bears on Problem 1039.
Depends on. No page of this wiki.
Acceptance. Reviewed: erdosproblems.com labels the problem proved and states
the lower bound and the upper bound as
proved by this paper, cited as [KLR25] (page last edited 2025-10-24), which the
corpus counts as documented independent acceptance by the site's curator, T. F.
Bloom (erdosproblems.com); the formal-conjectures file lists the logarithmic
form as solved without a formal proof, so the evidence lists no formalized
kind. Not refereed: the preprint is at its first arXiv version and no journal
version is recorded. Proof coverage: the card's digest only; the proof is
unverified by this corpus, and the standing rests on the site's acceptance.