Abstract
In a recent paper, Ng, Tang and Tsai (Math Ann 380, 1741–1766, https://doi.org/10.1007/s00208-020-02046-w, 2021) have found an explicit formula for the squeezing function of an annulus via the Loewner differential equation. Their result has led them to conjecture a corresponding formula for planar domains of any finite connectivity stating that the extremum in the squeezing function problem is achieved for a suitably chosen conformal mapping onto a circularly slit disk. In this paper we disprove this conjecture. We also give a conceptually simple potential-theoretic proof of the explicit formula for the squeezing function of an annulus which has the added advantage of identifying all extremal functions.
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Communicated by Ngaiming Mok.
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Gumenyuk, P., Roth, O. On the squeezing function for finitely connected planar domains. Math. Ann. 384, 1–24 (2022). https://doi.org/10.1007/s00208-021-02296-2
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DOI: https://doi.org/10.1007/s00208-021-02296-2