Skip to main content

Generalization of Carathéodory’s Inequality and the Bohr Radius for Multidimensional Power Series

  • Chapter

Part of the book series: Operator Theory: Advances and Applications ((OT,volume 158))

Abstract

In the present paper we generalize Carathéodory’s inequality for functions holomorphic in Cartan domains in Cn. In particular, in the case of functions holomorphic in the unit disk in C, this generalization of Carathéodory’s inequality implies the classical inequalities of Carahtéodory and Landau. As an application, new results on multidimensional analogues of Bohr’s theorem on power series are obtained. Furthermore, the estimate from below of Bohr radius is improved for the domain \(D = \{ z \in C^2 :\left| {z_1 } \right| + \left| {z_2 } \right| < 1\}\).

During the preparation of this work the author was supported by the Israel-Slovenia grant. Part of the work was completed in January-February 2001 during the author’s stay at the Institute of Mathematics, Physics and Mechanincs, Lujbljiana, Slovenia.

This is a preview of subscription content, log in via an institution.

Buying options

Chapter
USD   29.95
Price excludes VAT (USA)
  • Available as PDF
  • Read on any device
  • Instant download
  • Own it forever
eBook
USD   84.99
Price excludes VAT (USA)
  • Available as PDF
  • Read on any device
  • Instant download
  • Own it forever
Hardcover Book
USD   109.99
Price excludes VAT (USA)
  • Durable hardcover edition
  • Dispatched in 3 to 5 business days
  • Free shipping worldwide - see info

Tax calculation will be finalised at checkout

Purchases are for personal use only

Learn about institutional subscriptions

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. L. Aizenberg, Multidimensional analogues of Bohr’s theorem on power series, Proc. Amer. Math. Soc. 128 (2000), 1147–1155.

    Google Scholar 

  2. L. Aizenberg, Bohr Theorem, Encyclopedia of Mathematics, Supplement II (ed. M. Hazewinkel), Kluwer, Dordrecht, 2000, 76–78.

    Google Scholar 

  3. L. Aizenberg, A. Aytuna, P. Djakov, An abstract approach to Bohr’s phenomenon, Proc. Amer. Math. Soc. 128 (2000), 2611–2619.

    Google Scholar 

  4. L. Aizenberg, A. Aytuna, P. Djakov, Generalization of Bohr’s theorem for bases in spaces of holomorphic functions of several complex variables, J. Math. Anal. Appl. 258 (2001), 428–447.

    Google Scholar 

  5. L. Aizenberg, B.S. Mityagin, The spaces of functions analytic in multicircular domains, Sibir. Math. J. 1 (1960), 1953–1970 (Russian).

    Google Scholar 

  6. L. Aizenberg, N. Tarkhanov, A Bohr phenomenon for elliptic equations, Proc. London Math. Soc. 82 (2001), 385–401.

    Google Scholar 

  7. H.P. Boas Majorant series, J. Korean Math. Soc. 37 (2000), 321–337.

    Google Scholar 

  8. C. Bénéteau, A. Dahlner, D. Khavinson, Remarks on the Bohr phenomenon, Comput. Methods Func. Theory 4 (2004), 1–19.

    Google Scholar 

  9. H.P. Boas, D. Khavinson, Bohr’s power series theorem in several variables, Proc. Amer. Math. Soc. 125 (1997), 2975–2979.

    Google Scholar 

  10. H. Bohr, A theorem concerning power series, Proc. London Math.Soc. 13 (1914), 1–5.

    Google Scholar 

  11. C. Carathéodory, Über den Variabilitiitsbereich der Koeffizienten der Potenzreihen, die gegebene Werte nicht annehmen, Math. Ann. 64 (1907), 95–115.

    Google Scholar 

  12. J.G. van der Corput, C. Visser, Inequalities concerning polynomials and trigonometric polynomials, Neder. Acad. Wetensch. Proc. 49 (1946), 383–392.

    Google Scholar 

  13. A. Defant, L. Frerick, A logarithmic lower bound for the Bohr radii, 2004, Preprint.

    Google Scholar 

  14. P.B. Djakov, M.S. Ramanujan, A remark on Bohr’s theorem and its generalizations, J. Analysis, 8 (2000), 65–77.

    Google Scholar 

  15. E. Landau, D. Gaier, Darstellung und Begründung einiger neuerer Ergebnisse der Funktionentheorie, Springer-Verlag, 1986.

    Google Scholar 

  16. D.S. Mitrinovic, J.E. Pecaric, A.M. Frank, Classical and new inequalities in Analysis, Kluwer, Dordrecht, 1993.

    Google Scholar 

  17. Wolfram Research, Mathematica 3.0, 1996.

    Google Scholar 

Download references

Author information

Authors and Affiliations

Authors

Editor information

Editors and Affiliations

Rights and permissions

Reprints and permissions

Copyright information

© 2005 Birkhäuser Verlag Basel/Switzerland

About this chapter

Cite this chapter

Aizenberg, L. (2005). Generalization of Carathéodory’s Inequality and the Bohr Radius for Multidimensional Power Series. In: Eiderman, V.Y., Samokhin, M.V. (eds) Selected Topics in Complex Analysis. Operator Theory: Advances and Applications, vol 158. Birkhäuser Basel. https://doi.org/10.1007/3-7643-7340-7_6

Download citation

Publish with us

Policies and ethics