×

A domain with non-plurisubharmonic squeezing function. (English) Zbl 1396.32013

Suppose \(\Omega\) is an (arbitrary) bounded domain in \(\mathbb{C}^n\). The squeezing function of \(\Omega\) is defined as follows. Let \(p\in\Omega\) and consider the set of holomorphic embeddings in the unit ball \(f:\Omega\to\mathbb{B}^n\) satisfying \(f(p)=0\). For each such \(f\) we define the real number \[ S_\Omega(p,f)=\sup\left\{ r>0: r\mathbb{B}^n\subset f(\Omega)\right\}. \] The squeezing function is the map \(S_{\Omega}:\Omega\to \mathbb{R}\) defined as \[ S_{\Omega}(p)=\sup_f\{S_\Omega(p,f)\} \] where the supremum is taken over all such embeddings. Squeezing functions are invariant under biholomorphic maps and have been the object of study as a means of understanding the geometric and analytic structures of bounded domains. It is well known that functions which are naturally defined on pseudoconvex domains often have plurisubharmonic properties and an open question has been whether it is always true that the squeezing function of a strictly pseudoconvex domain with smooth boundary is plurisubharmonic. In this paper the authors give a negative answer to this question by constructing a bounded strictly pseudoconvex domain with smooth boundary whose squeezing function is not plurisubharmonic. The methods are based on explicit estimates involving the Kobayashi and Caratheodory metrics and the constructed squeezing function that is shown not to satisfy the maximum principle and thus cannot be plurisubharmonic.

MSC:

32T15 Strongly pseudoconvex domains
32U05 Plurisubharmonic functions and generalizations
32F45 Invariant metrics and pseudodistances in several complex variables

References:

[1] Berndtsson, B.: Subharmonicity properties of the Bergman kernel and some other functions associated to pseudoconvex domains. Ann. Inst. Fourier 56, 1633-1662 (2006). (Grenoble) · Zbl 1120.32021 · doi:10.5802/aif.2223
[2] Deng, F., Guan, Q., Zhang, L.: Some properties of squeezing functions on bounded domains. Pacific J. Math. 257, 319-341 (2012) · Zbl 1254.32015 · doi:10.2140/pjm.2012.257.319
[3] Deng, F., Guan, Q., Zhang, L.: Properties of squeezing functions and global transformations of bounded domains. Trans. Am. Math. Soc. 368, 2679-2696 (2016) · Zbl 1338.32015 · doi:10.1090/tran/6403
[4] Diederich, K., Fornæss, J.E.: Boundary Behavior of the Bergman Metric. arXiv:1504.02950 · Zbl 0533.32012
[5] Diederich, K., Fornæss, J.E., Wold, E.F.: Exposing points on the boundary of a strictly pseudoconvex or a locally convexifiable domain of finite 1-type. J. Geom. Anal. 24, 2124-2134 (2014) · Zbl 1312.32006 · doi:10.1007/s12220-013-9410-0
[6] Fornæss, JE; Wold, EF, An estimate for the squeezing function and estimates of invariant metrics. Complex analysis and geometry, No. 144, 135-147 (2015), Tokyo · Zbl 1330.32009
[7] Kim, K.-T., Zhang, L.: On the uniform squeezing property of convex domains in \[\mathbb{C}^nCn\]. Pacif. J. Math. 282, 341-358 (2016) · Zbl 1350.32019 · doi:10.2140/pjm.2016.282.341
[8] Liu, K., Sun, X., Yau, S.-T.: Canonical metrics on the moduli space of Riemann surfaces, I. J. Differ. Geom. 68, 571-637 (2004) · Zbl 1078.30038 · doi:10.4310/jdg/1116508767
[9] Liu, K., Sun, X., Yau, S.-T.: Canonical metrics on the moduli space of Riemann surfaces, II. J. Differ. Geom. 69, 163-216 (2005) · Zbl 1086.32011 · doi:10.4310/jdg/1121540343
[10] Ruscheweyh, S.: Two remarks on bounded analytic functions. Serdica 11, 200-202 (1985) · Zbl 0581.30009
[11] Yamaguchi, H.: Variations of pseudoconvex domains over \[\mathbb{C}^nCn\]. Michigan Math. J. 36, 415-457 (1989) · Zbl 0692.31004 · doi:10.1307/mmj/1029004011
[12] Yeung, S.-K.: Geometry of domains with the uniform squeezing property. Adv. Math. 221, 547-569 (2009) · Zbl 1165.32004 · doi:10.1016/j.aim.2009.01.002
This reference list is based on information provided by the publisher or from digital mathematics libraries. Its items are heuristically matched to zbMATH identifiers and may contain data conversion errors. In some cases that data have been complemented/enhanced by data from zbMATH Open. This attempts to reflect the references listed in the original paper as accurately as possible without claiming completeness or a perfect matching.