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On the isometric composition operators on the Bloch space in \(\mathbb C^n\). (English) Zbl 1166.32300

Summary: Let \(\varphi \) be a holomorphic self-map of a bounded homogeneous domain \(D\) in \(\mathbb C^n\). In this work, we show that the composition operator \(C_\varphi :f\mapsto f\circ \varphi \) is bounded on the Bloch space \(\mathcal B\) of the domain and provide estimates on its operator norm. We also give a sufficient condition for \(\varphi \) to induce an isometry on \(\mathcal B\). This condition allows us to construct non-trivial examples of isometric composition operators in the case when \(D\) has the unit disk as a factor. We then obtain some necessary conditions for \(C_\varphi \) to be an isometry on \(\mathcal B\) when \(D\) is a Cartan classical domain. Finally, we give the complete description of the spectrum of the isometric composition operators in the case of the unit disk and for a wide class of symbols on the polydisk.

MSC:

32A37 Other spaces of holomorphic functions of several complex variables (e.g., bounded mean oscillation (BMOA), vanishing mean oscillation (VMOA))
47B33 Linear composition operators

References:

[1] R.F. Allen, F. Colonna, Isometries and spectra of multiplication operators on the bloch space, Bull. Austral. Math. Soc., in press; R.F. Allen, F. Colonna, Isometries and spectra of multiplication operators on the bloch space, Bull. Austral. Math. Soc., in press · Zbl 1163.47027
[2] Cartan, E., Sur les domains bornés de l’espace de \(n\) variable complexes, Abh. Math. Sem. Univ. Hamburg, 11, 116-162 (1935) · JFM 61.0370.03
[3] Cima, J., The basic properties of Bloch functions, Int. J. Math. Math. Sci. (2), 3, 369-413 (1979) · Zbl 0423.30022
[4] Cohen, J. M.; Colonna, F., Bounded holomorphic functions on bounded symmetric domains, Trans. Amer. Math. Soc. (1), 343, 135-156 (1994) · Zbl 0804.32018
[5] Cohen, J. M.; Colonna, F., Preimages of one-point sets of Bloch and normal functions, Mediterr. J. Math., 3, 513-532 (2006) · Zbl 1167.30323
[6] Cohen, J. M.; Colonna, F., Isometric composition operators on the Bloch space in the polydisk, (Contemp. Math., vol. 454 (2008)), 9-21 · Zbl 1163.32002
[7] Colonna, F., Characterisation of the isometric composition operators on the Bloch space, Bull. Austral. Math. Soc., 72, 283-290 (2005) · Zbl 1088.30025
[8] Colonna, F., Bloch and normal functions and their relation, Rend. Circ. Mat. Palermo Ser. II, XXXVIII, 161-180 (1989) · Zbl 0685.30027
[9] Colonna, F., The Bloch constant of bounded analytic functions, J. London Math. Soc. (2), 36, 95-101 (1987) · Zbl 0586.30029
[10] Conway, J. B., A Course in Functional Analysis (1994), Springer-Verlag: Springer-Verlag New York
[11] Cowen, C.; MacCluer, B., Composition Operators on Spaces of Analytic Functions, Stud. in Adv. Math. (1995), CRC Press: CRC Press Boca Raton · Zbl 0873.47017
[12] Drucker, D., Exceptional Lie algebras and the structure of Hermitian symmetric spaces, Mem. Amer. Math. Soc., 208, 1-207 (1978) · Zbl 0395.17009
[13] Gromov, M., Structures Métriques pour les Variétés Riemaniennes (1981), Cedic/Fernand Nathan: Cedic/Fernand Nathan Paris · Zbl 0509.53034
[14] Hahn, K. T., Holomorphic mappings of the hyperbolic space into the complex Euclidean space and the Bloch theorem, Canad. J. Math., 27, 446-458 (1975) · Zbl 0269.32014
[15] Helgason, S., Differential Geometry and Symmetric Spaces (1962), Academic Press: Academic Press New York-London · Zbl 0122.39901
[16] Kobayashi, S., Hyperbolic Manifolds and Holomorphic Mappings, an Introduction (2005), World Scientific: World Scientific London · Zbl 1084.32018
[17] Korányi, A., A Schwarz lemma for bounded symmetric domains, Proc. Amer. Math. Soc., 17, 210-213 (1966) · Zbl 0138.06502
[18] Krantz, S. G.; Ma, D., Bloch functions on strongly pseudoconvex domains, Indiana Univ. Math. J., 37, 145-163 (1988) · Zbl 0628.32006
[19] Martín, M. J.; Vukotić, D., Isometries of the Bloch space among the composition operators, Bull. London Math. Soc., 39, 151-155 (2007) · Zbl 1115.47024
[20] Rudin, W., Function Theory in Unit Ball of \(C^n (1980)\), Springer-Verlag: Springer-Verlag New York · Zbl 0495.32001
[21] Rudin, W., Function Theory in Polydiscs (1969), W.A. Benjamin, Inc.: W.A. Benjamin, Inc. New York · Zbl 0177.34101
[22] Timoney, R. M., Bloch functions in several complex variables, I, Bull. London Math. Soc., 12, 241-267 (1980) · Zbl 0416.32010
[23] Timoney, R. M., Bloch functions in several complex variables, II, J. Reine Angew. Math., 319, 1-22 (1980) · Zbl 0425.32008
[24] Shi, J. H.; Luo, L., Composition operators on the Bloch space of several complex variables, Acta Math. Sinica (N.S.), 16, 85-98 (2000) · Zbl 0967.32007
[25] Zhang, G., Bloch constants of bounded symmetric domains, Trans. Amer. Math. Soc., 349, 2941-2949 (1997) · Zbl 0870.32011
[26] Zhu, K., Operator Theory in Function Spaces (1990), Marcel Dekker: Marcel Dekker New York · Zbl 0706.47019
[27] Zhu, K., Spaces of Holomorphic Functions in the Unit Ball (2005), Springer: Springer New York · Zbl 1067.32005
[28] Zhou, Z.; Shi, J., Composition operators on the Bloch space in polydisks, Complex Variables, 46, 73-88 (2001) · Zbl 1026.47018
[29] Xiong, C., Norm of composition operators on the Bloch space, Bull. Austral. Math. Soc., 70, 293-299 (2004) · Zbl 1062.30038
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