×

Covering the sphere with equal circles. (English) Zbl 1370.52036

Given \(n\), how can a 2-sphere be covered by \(n\) congruent circles with a radius as small as possible? The author proves that an arrangement of eight circles found by Schütte is optimal and provides the solution for \(n=8\) [K. Schütte, Math. Ann. 129, 181–186 (1955; Zbl 0066.14403)]. Also determined is the combinatorial type of a solution for \(n=9\).

MSC:

52C15 Packing and covering in \(2\) dimensions (aspects of discrete geometry)
52C17 Packing and covering in \(n\) dimensions (aspects of discrete geometry)
51M16 Inequalities and extremum problems in real or complex geometry

Citations:

Zbl 0066.14403

Software:

plantri
Full Text: DOI

References:

[1] Brinkmann, G., McKay, B.: Plantri. http://users.cecs.anu.edu.au/ bdm/plantri/. Accessed 01 Oct 2016 · Zbl 0491.52004
[2] Brückner, M.: Vielecke und Vielflache. Teubner, Leipzig (1900) · JFM 31.0479.04
[3] Engel, P.: On the enumeration of polyhedra. Discrete Math. 41(2), 215-218 (1982) · Zbl 0491.52004 · doi:10.1016/0012-365X(82)90208-4
[4] Fejes Tóth, G.: Kreisüberdeckungen der Sphäre. Stud. Sci. Math. Hung. 4, 225-247 (1969) · Zbl 0197.18602
[5] Fejes Tóth, L.: Lagerungen in der Ebene, auf der Kugel und im Raum. Die Grundlehren der Mathematischen Wissenschaften, vol. 65, 2nd edn. Springer, Berlin (1972) · Zbl 0229.52009 · doi:10.1007/978-3-642-65234-9
[6] Heppes, A.: Az Elliptikus sík Legritkább Fedése Négy Egybevágó Körrel [The thinnest covering of the elliptic plane by four congruent circles]. Mat. Lapok (N.S.) 8/9, 4-6 (2003) · Zbl 1027.52010
[7] Jucovič, E.: Niektore pokrytia gul’obvej plochy zhodnymi kruhmi. Mat.-Fyz. Čas. Slovensk. Akad. Vied. 10, 99-104 (1960) (in Slovak)
[8] Schütte, K.: Überdeckungen der Kugel mit höchstens acht Kreisen. Math. Ann. 129, 181-186 (1955) · Zbl 0066.14403 · doi:10.1007/BF01362364
[9] Sigl, R.: Ebene und Sphärische Trigonometrie. H. Wichmann, Karlsruhe (1977) · Zbl 0177.27403
[10] Tarnai, T., Gáspár, Zs.: Covering a sphere by equal circles, and the rigidity of its graph. Math. Proc. Camb. Philos. Soc. 110(1), 71-89 (1991) · Zbl 0736.52009
This reference list is based on information provided by the publisher or from digital mathematics libraries. Its items are heuristically matched to zbMATH identifiers and may contain data conversion errors. In some cases that data have been complemented/enhanced by data from zbMATH Open. This attempts to reflect the references listed in the original paper as accurately as possible without claiming completeness or a perfect matching.