Abstract
We select a class of pyramids of a particular shape and propose a conjecture that precisely these pyramids are of greatest surface area among the closed convex polyhedra having evenly many vertices and the unit geodesic diameter. We describe the geometry of these pyramids. The confirmation of our conjecture will solve the “doubly covered disk” problem of Alexandrov. Through a connection with Reuleaux polygons we prove that on the plane the convex n-gon of unit diameter, for odd n, has greatest area when it is regular, whereas this is not so for even n.
Similar content being viewed by others
References
Blaschke W., Kreis und Kugel, Walter de Gruyter, Berlin (1936).
Bonnesen T. and Fenchel W., Theorie der Konvexen Körper, Julius Springer, Berlin (1934).
Schilling F., “Die Theorie and Konstruktion der Kurven Konstanter Breite,” Z. Math. Phys., 63, 67–136 (1914).
Blaschke W., “Konvexe Bereich Gegebener Konstanter Breite und Kleinsten Inhalts,” Math. Ann., 76, 504–513 (1915).
Kupitz Ya. S. and Martini H., “On the isoperimetric inequalities for Reuleaux polygons,” J. Geometry, 68, No. 2, 179–191 (2000).
Yau S. T., “Problem section,” in: Seminar on Differential Geometry, Princeton Univ. Press, Princeton, 1982, p. 684 (Ann. Math. Stud.; 102).
Zalgaller V. A., “An isoperimetric problem for tetrahedra,” J. Math. Sci., New York, 140, No. 4, 511–527 (2007).
Author information
Authors and Affiliations
Corresponding author
Additional information
To dear Yuriĭ Grigor’evich Reshetnyak on his 80th birthday.
Original Russian Text Copyright © 2009 Zalgaller V. A.
__________
Rehovot. Translated from Sibirskiĭ Matematicheskiĭ Zhurnal, Vol. 50, No. 5, pp. 1070–1082, September–October, 2009.
Rights and permissions
About this article
Cite this article
Zalgaller, V.A. A conjecture on convex polyhedra. Sib Math J 50, 846–855 (2009). https://doi.org/10.1007/s11202-009-0095-3
Received:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s11202-009-0095-3