The curvature of level curves
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- by Dorothy Browne Shaffer
- Trans. Amer. Math. Soc. 158 (1971), 143-150
- DOI: https://doi.org/10.1090/S0002-9947-1971-0277695-5
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Abstract:
Sharp bounds are derived for the curvature of level curves of analytic functions in the complex plane whose logarithmic derivative has the representation $c/(w - g(w))$, where $g(w)$ is analytic for $|w| > a$ and $|g(w)| \leqq a,c$ real. These results are applied in particular to lemniscates and sharpened for the level curves of lacunary polynomials. Extensions to the level curves of Green’s function and rational functions are indicated.References
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Bibliographic Information
- © Copyright 1971 American Mathematical Society
- Journal: Trans. Amer. Math. Soc. 158 (1971), 143-150
- MSC: Primary 30.10
- DOI: https://doi.org/10.1090/S0002-9947-1971-0277695-5
- MathSciNet review: 0277695