Abstract
Let K be a body in the plane and let \(\lambda <1\) be a positive real number. Suppose that for every \(x\in \mathbb R^2\) such that \(\lambda K + x\) is exteriorly tangent to K, the common support cone of K and \(\lambda K + x\) has a constant angle \(\alpha \). Suppose that one of the following conditions is satisfied: (a) K is a body of constant width, (b) K is centrally symmetric. Then K is a Euclidean disc.
Similar content being viewed by others
References
Chinn, W.G., Steenrod, N.E.: First Concepts of Topology. The Geometry of Mappings of Segments, Curves, Circles, and Disks, New Mathematical Library, vol. 18. Random House, New York (1966)
Cieślak, W., Miernowski, A., Mozgawa, W.: Isoptics of a closed strictly convex curve. Lect. Notes Math. 1481, 28–35 (1991)
Cieślak, W., Miernowski, A., Mozgawa, W.: Isoptics of a closed strictly convex curve II. Rend. Sem. Mat. Univ. Padova 96, 37–49 (1996)
García-Jiménez, M., González, E., Jerónimo-Castro, J.: A characterization of the Euclidean sphere with respect to an isoptic surface. Monatsh. Math. 181, 601–607 (2016)
Groemer, H.: Geometric Applications of Fourier Series and Spherical Harmonics. Cambridge University Press, Cambridge (1996)
Gutkin, E.: Capillary floating and the billiard ball problem. J. Math. Fluid Mech. 14, 363–382 (2012)
Hammer, P.C.: Convex curves of constant Minkowski breadth. Proc. Sympos. Pure Math. VII, 291–304 (1963)
Jerónimo-Castro, J., Rojas-Tapia, M.A., Velasco-García, U., Yee-Romero, C.: An isoperimetric type inequality for isoptic curves of convex bodies. Results Math. 75, 1–12 (2020)
Valentine, F.A.: Convex Sets. McGraw-Hill Series in Higher Mathematics, McGraw-Hill, New York (1964)
Author information
Authors and Affiliations
Corresponding author
Additional information
Publisher's Note
Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
Rights and permissions
About this article
Cite this article
Jerónimo-Castro, J. A Characterization of the Disc by the Angle of the Support Cone. Results Math 76, 130 (2021). https://doi.org/10.1007/s00025-021-01446-x
Received:
Accepted:
Published:
DOI: https://doi.org/10.1007/s00025-021-01446-x