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A New Approach to Support Point Theory for the Class \(\mathcal{S}\)

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Abstract

In this paper, we introduce a new technique for measuring the hypothetical non-monotonicity of the argument of the vector tracing the omitted arc of a support point of the class \({\cal S}\). It has been previously shown that the number of sign changes of (arg w(t))′ on the omitted arc is finite. Here, we derive upper bounds for that number in terms of both the spherical and Schwarzian derivatives. Thus, our innovative approach identifies an inherently interesting connection between support point theory and these derivatives.

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References

  1. J. E. Brown, Geometric properties of a class of support points of univalent functions, Trans. Amer. Math. Soc. 256 (1979), 371–382.

    Article  MathSciNet  MATH  Google Scholar 

  2. L. Brickman and D. R. Wilken, Support points of the set of univalent functions, Proc. Amer. Math. Soc. 42 no.2 (1974), 523–528.

    Article  MathSciNet  MATH  Google Scholar 

  3. P. L. Duren, Univalent Functions, Springer-Verlag, New York, 1983.

    MATH  Google Scholar 

  4. W. Hengartner and G. Schober, Some new properties of support points for compact families of univalent functions in the unit disk, Michigan Math. J. 23 (1976), 207–216.

    Article  MathSciNet  MATH  Google Scholar 

  5. I. Q. Hibschweiler, Geometric properties of some support points of univalent functions, Houston J. Math. 21 no.1 (1995), 95–102.

    MathSciNet  MATH  Google Scholar 

  6. W. Kirwan and R. Pell, Extremal properties of a class of slit conformal mappings, Michigan Math. J. 25 (1978), 223–232.

    Article  MathSciNet  MATH  Google Scholar 

  7. K. Pearce, New support points of \(\mathcal{S}\) and extreme points of \(\mathcal{H}\mathcal{S}\), Proc. Amer. Math. Soc. 81 no.3 (1981), 425–428.

    MathSciNet  MATH  Google Scholar 

  8. R. Pell, Support point functions and the Loewner variation, Pacific J. Math., 86 no.2 (1980), 561–564.

    Article  MathSciNet  MATH  Google Scholar 

  9. A. Pfluger, Lineare Extremalprobleme bei schlichten Funktionen, Ann. Acad. Sci. Fenn. Ser. AI 489 (1971).

  10. S. M. Zemyan, On the extremal curvature and torsion of stereographically projected analytic curves, Tamkang J. Math. 28 no.2 (1997), 101–117.

    MathSciNet  MATH  Google Scholar 

  11. S. M. Zemyan, On some new properties of the spherical curvature of stereographically projected analytic curves, Int. J. Math. Math. Sci. 2003 no.26 (2003), 1633–1644.

    Article  MathSciNet  MATH  Google Scholar 

  12. S. M. Zemyan, The existence of a waver point on the omitted arc of a support point of the class \(\mathcal{S}\), Complex Variables 48 no.9 (2003), 791–796.

    Article  MathSciNet  MATH  Google Scholar 

  13. —, On the omitted arc of a support point of the class \({\cal S}\), submitted.

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Correspondence to Stephen M. Zemyan.

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Zemyan, S.M. A New Approach to Support Point Theory for the Class \(\mathcal{S}\) . Comput. Methods Funct. Theory 5, 1–17 (2005). https://doi.org/10.1007/BF03321083

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