Abstract
Among others, we prove that if a convex body \(\mathcal {K}\) and a ball \({\mathcal B}\) have equal constant volumes of caps and equal constant areas of sections with respect to the supporting planes of a sphere, then \({\mathcal K}\equiv {\mathcal B}\).
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Notes
[1, Theorem 1] gives the same conclusion in the plane for disc-isosectioned convex bodies
Although \(\hbar ({\varvec{u}}_{{\varvec{\xi }}},r)=\hbar (-{\varvec{u}}_{{\varvec{\xi }}},-r)\) this parametrization is locally bijective.
Recently Kincses [5] informed the authors in detail that he is very close to finish the construction of two different \(\mathcal D\)-equisectioned convex bodies \(\mathcal K_1\) and \(\mathcal K_2\) in the plane for a disk \(\mathcal D\).
References
Barker, J.A., Larman, D.G.: Determination of convex bodies by certain sets of sectional volumes. Discrete Math. 241, 79–96 (2001)
Falconer, K.J.: X-ray problems for point sources. Proc. Lond. Math. Soc. 46, 241–262 (1983)
Gardner, R.J.: Geometric Tomography, 2nd edn. Encyclopedia of Mathematics and its Applications, vol. 58. Cambridge University Press, Cambridge (2006) (1st edition in 1996)
Katok, A., Hasselblatt, B.: Introduction to the Modern Theory of Dynamical Systems. Cambridge University Press, Cambridge (1995)
Kincses, J.: Oral discussion (2013)
Kurusa, Á., Ódor, T.: Isoptic characterization of spheres, manuscript (2014)
Kurusa, Á., Ódor, T.: Spherical floating body, manuscript (2014)
Nakajima, S.: Eine charakteristicische Eigenschaft der Kugel. Jber. Dtsch. Math. Verein 35, 298–300 (1926)
Ódor, T.: Rekonstrukciós, karakterizációs és extrémum problémák a geometriában. PhD dissertation, Budapest (1994) (in hungarian; title in english: Problems of reconstruction, characterization and extremum in geometry)
Ódor, T.: Ball characterizations by visual angles and sections, unpublished manuscript (2003)
Wikipedia: Beta function. http://en.wikipedia.org/wiki/Beta_function
Wikipedia: Gamma function. http://en.wikipedia.org/wiki/Gamma_function
Wikipedia: Spherical cap. http://en.wikipedia.org/wiki/Spherical_cap
Acknowledgments
This research was supported by the European Union and co-funded by the European Social Fund under the project “Telemedicine-focused research activities on the field of Mathematics, Informatics and Medical sciences” of project number ‘TÁMOP-4.2.2.A-11/1/KONV-2012-0073”. The authors appreciate János Kincses for discussions of the problems solved in this paper.
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Kurusa, Á., Ódor, T. Characterizations of balls by sections and caps. Beitr Algebra Geom 56, 459–471 (2015). https://doi.org/10.1007/s13366-014-0203-9
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DOI: https://doi.org/10.1007/s13366-014-0203-9