The paper gives sufficient conditions for projections of certain pseudoconcave sets to be open. More specifically, it is shown that the range of an analytic set-valued function whose values are simply connected planar continua is open, provided there does not exist a point which belongs to boundaries of all the fibers. The main tool is a theorem on existence of analytic discs in certain polynomially convex hulls, obtained earlier by the author.
@article{bwmeta1.element.bwnjournal-article-smv122i2p117bwm, author = {Zbigniew S\l odkowski}, title = {An open mapping theorem for analytic multifunctions}, journal = {Studia Mathematica}, volume = {122}, year = {1997}, pages = {117-122}, zbl = {0873.32012}, language = {en}, url = {http://dml.mathdoc.fr/item/bwmeta1.element.bwnjournal-article-smv122i2p117bwm} }
Słodkowski, Zbigniew. An open mapping theorem for analytic multifunctions. Studia Mathematica, Tome 122 (1997) pp. 117-122. http://gdmltest.u-ga.fr/item/bwmeta1.element.bwnjournal-article-smv122i2p117bwm/
[00000] [BaHa] L. Baribeau and S. Harbottle, Two new open mapping theorems for analytic multifunctions, Proc. Amer. Math. Soc. 115 (1992), 1009-1012. | Zbl 0755.30040
[00001] [Ok] K. Oka, Note sur les familles de fonctions analytiques multiformes etc., J. Sci. Hiroshima Univ. 4 (1934), 93-98. | Zbl 60.0243.06
[00002] [Ra1] T. J. Ransford, Open mapping, inversion and implicit function theorems for analytic multivalued functions, Proc. London Math. Soc. 49 (1984), 537-562. | Zbl 0526.46045
[00003] [Ra2] T. J. Ransford, On the range of an analytic multivalued function, Pacific J. Math. 123 (1986), 421-439. | Zbl 0553.30034
[00004] [Sł1] Z. Słodkowski, Analytic set-valued functions and spectra, Math. Ann. 256 (1981), 363-386. | Zbl 0452.46028
[00005] [Sł2] Z. Słodkowski, Polynomial hulls in and quasi-circles, Ann. Scuola Norm. Sup. Pisa (4) 16 (1989), 367-391.