Skip to main content
Log in

Limit Curves for Zeros of Sections of Exponential Integrals

  • Published:
Constructive Approximation Aims and scope

Abstract

We are interested in studying the asymptotic behavior of the zeros of partial sums of power series for a family of entire functions defined by exponential integrals. The zeros grow on the order of \(O(n)\), and after rescaling, we explicitly calculate their limit curve. We find that the rate at which the zeros approach the curve depends on the order of the singularities/zeros of the integrand in the exponential integrals. As an application of our findings, we derive results concerning the zeros of partial sums of power series for Bessel functions of the first kind.

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

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5

Similar content being viewed by others

References

  1. Anderson, N., Saff, E.B., Varga, R.S.: On the Eneström-Kakeya theorem and its sharpness. Linear Algebra Appl. 28, 5–16 (1979)

    Article  MATH  MathSciNet  Google Scholar 

  2. Andrievskii, V.V., Carpenter, A.J., Varga, R.S.: Angular distribution of zeros of the partial sums of \(e^z\) via the solution of inverse logarithmic potential problem. Comput. Methods Funct. Theory 6(2), 447–458 (2006)

    Article  MATH  MathSciNet  Google Scholar 

  3. Bleher, P., R. Mallison, Jr.: Zeros of sections of exponential sums, Int. Math. Res. Not. Art. ID 38937: 49 (2006)

  4. Boas Jr, R.P.: Entire Functions. Academic Press Inc., New York (1954)

    MATH  Google Scholar 

  5. Boyer, R., Goh, W.M.Y.: On the zero attractor of the Euler polynomials. Adv. in Appl. Math. 38(1), 97–132 (2007)

    Article  MATH  MathSciNet  Google Scholar 

  6. Buckholtz, J.D.: A characterization of the exponential series, Amer. Math. Monthly 73 no. 4, part II, 121–123 (1966)

  7. Carpenter, A.J., Varga, R.S., Waldvogel, J.: Asymptotics for the zeros of the partial sums of \(e^z\). I. Rocky Mt. J. Math. 21(1), 99–120 (1991)

    Article  MATH  MathSciNet  Google Scholar 

  8. Dilcher, K., Rubel, L.A.: Zeros of sections of divergent power series. J. Math. Anal. Appl. 198(1), 98–110 (1996)

    Article  MATH  MathSciNet  Google Scholar 

  9. Edrei, A., Saff, E.B., Varga, R.S.: Zeros of Sections of Power Series. Lecture Notes in Mathematics, vol. 1002. Springer-Verlag, Berlin (1983)

    Google Scholar 

  10. Jentzsch, R.: Untersuchungen zur Theorie der Folgen analytischer Funktionen. Acta Math. 41(1), 219–251 (1916)

    Article  MathSciNet  Google Scholar 

  11. Marden, M.: Geometry of Polynomials, Second edition. Mathematical Surveys, No. 3, American Mathematical Society, Providence, R.I. (1966)

  12. Miller, P.D.: Applied Asymptotic Analysis, Graduate Studies in Mathematics, vol. 75. American Mathematical Society, Providence, R.I. (2006)

    Google Scholar 

  13. Norfolk, T.S.: Some observations on the Saff–Varga width conjecture. Rocky Mt. J. Math. 21(1), 529–538 (1991)

    Article  MATH  MathSciNet  Google Scholar 

  14. Norfolk, T.S.: On the zeros of the partial sums to \({}_1F_1(1;b;z)\). J. Math. Anal. Appl. 218(2), 421–438 (1998)

    Article  MATH  MathSciNet  Google Scholar 

  15. Norfolk, T.S.: Asymptotics of the partial sums of a set of integral transforms, Numer. Algorithms 25 (2000), no. 1–4, 279–291, Mathematical journey through analysis, matrix theory and scientific computation (Kent, OH, 1999)

  16. Rosenbloom, P.C.: On sequences of polynomials, especially sections of power series, Ph.D. thesis, Stanford University, Abstracts in Bull. Am. Math. Soc. 48 (1942), 839(49), 1943, 689 (1944)

  17. Rosenbloom, P.C.: Distribution of zeros of polynomials. In: Kaplan, W. (ed.) Lectures on Functions of a Complex Variable, pp. 265–285. The University of Michigan Press, Ann Arbor (1955)

    Google Scholar 

  18. Slepian, D., Pollak, H.O.: Prolate spheroidal wave functions, Fourier analysis and uncertainty. I. Bell Syst. Tech. J. 40, 43–63 (1961)

    Article  MATH  MathSciNet  Google Scholar 

  19. Szegő, G.: Über eine Eigenschaft der Exponentialreihe. Berlin Math. Ges. Sitzungsber. 23, 50–64 (1924)

    Google Scholar 

  20. Varga, R.S., Carpenter, A.J.: Zeros of the partial sums of \(\cos (z)\) and \(\sin (z)\). III. Appl. Numer. Math. 60(4), 298–313 (2010)

    Article  MATH  MathSciNet  Google Scholar 

  21. Vargas, A.R.: Zeros of sections of some power series, Master’s thesis, Dalhousie University (2012). arXiv:1208.5186 [math.NT]

  22. Watson, G.N.: A Treatise on the Theory of Bessel Functions, Cambridge Mathematical Library, Cambridge University Press, Cambridge, 1995, Reprint of the second edition (1944)

Download references

Acknowledgments

The author would like to thank the referees for their valuable questions and comments.

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to Antonio R. Vargas.

Additional information

Communicated by Edward B. Saff.

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Vargas, A.R. Limit Curves for Zeros of Sections of Exponential Integrals. Constr Approx 40, 219–239 (2014). https://doi.org/10.1007/s00365-014-9241-7

Download citation

  • Received:

  • Revised:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s00365-014-9241-7

Keywords

Mathematics Subject Classification

Navigation